ケインズの『一般理論』第１章～第１５章（対訳）
この抄訳を作るにあたって使用したテキストはネット上にあるものである。参考にした
仏訳はこちら。
ただしそれらは共通して第３章第２節注４に<脱落>がある。この脱落のないテキストは
中国人がつくったものだけらしい。
主に参考にした和訳は東洋経済新報社から出ている塩野谷祐一氏の普及版第３刷である。
全体的な精度が最も高いのがこの訳だが、岩波文庫版は文学的表現力において、
講談社学術文庫版は用語の斬新さに見るべきものがあると思われる。第二版はかなり改善されてさらに分かりやすくなっているようである。
経済用語は有斐閣『経済辞典』、岩波『現代経済学辞典』を参考にした。変える場合も辞典の用語を併記した。
参考文献は宮崎・伊東編『ケインズ／一般理論 コンメンタール』、滝川好夫著『図解雑学ケインズ経済学』（ナツメ社）など。
原文のイタリック体はなるべく訳語を「」に入れた。(..)は原文のカッコであり、（＝..）は訳者の注釈あるいは解釈を示すカッコである）
John Maynard Keynes (1936)
The General Theory of Employment, Interest and Money
Written: 1935;
Source: The General Theory of Employment, Interest and Money by John
Maynard Keynes, Fellow of the King's College, Cambridge, published by
Harcourt, Brace and Company, and printed in the U.S.A. by the
Polygraphic Company of America, New York;
First Published: Macmillan Cambridge University Press, for Royal Economic Society in 1936;
Transcribed for M.I.A., corrected and formatted by Andy Blunden;
This Edition: marxists.org 2002.
“Our criticism of the accepted classical theory of economics has
consisted not so much in finding logical flaws in its analysis as in
pointing out that its tacit assumptions are seldom or never satisfied,
with the result that it cannot solve the economic problems of the
actual world.” [Chapter 24]
Preface
まえがき
Book I Introduction
第１巻 序論
Chapter 1: The General Theory
第１章 一般理論
Chapter 2: The Postulates of the Classical Economics
第２章 古典派経済学の公理
Chapter 3: The Principle of Effective Demand
第３章 有効需要の原理
Book II Definitions and Ideas
第２巻 定義と概念
Chapter 4: The Choice of Units
第４章 単位の選択
Chapter 5. Expectation as Determining Output and Employment
第５章 産出高と雇用を決定するものとしての予想
Chapter 6. The Definition of Income, Saving and Investment
第６章 所得と貯蓄と投資の定義
Appendix on User Cost
付録、使用費用について
Chapter 7. The Meaning of Saving and Investment Further Considered
第７章 貯蓄と投資の意味の再考
Book III The Propensity to Consume
第３巻 消費性向
Chapter 8. The Propensity to Consume: I. The Objective Factors
第８章 消費性向 １ 客観的要因
Chapter 9. The Propensity to Consume: II. The Subjective Factors
第９章 消費性向 ２ 主観的要因
Chapter 10. The Marginal Propensity to Consume and the Multiplier
第１０章 限界消費性向と乗数
Book IV The Inducement to Invest
第４巻 投資誘引
Chapter 11. The Marginal Efficiency of Capital
第１１章 資本の限界効率
Chapter 12. The State of Long-term Expectation
第１２章 長期予想の状況
Chapter 13. The General Theory of the Rate of Interest
第１３章 利子率についての一般理論
Chapter 14. The Classical Theory of the Rate of Interest
第１４章 利子率についての古典的理論
Appendix on the Rate of Interest in Marshall and Ricardo
付録、マーシャルとリカードの利子率について
Chapter 15. The Psychological and Business Incentives to Liquidity
第１５章 流動性に対する心理的事業的な誘引
Chapter 16. Sundry Observations on the Nature of Capital
第１６章 資本の性格についての多様な観察
Chapter 17. The Essential Properties of Interest and Money
第１７章 利子率と貨幣の重要な属性
Chapter 18. The General Theory of Employment Re-stated
第１８章 雇用の一般理論再論
Book V Money-Wages and Prices
第５巻 賃金貨幣と価格
Chapter 19. Changes in Money-Wages
第１９章 貨幣賃金の変化について
Appendix on Prof. Pigou's “Theory of Unemployment”
付録、ピグー教授の『失業の理論』について
Chapter 20. The Employment Function
第２０章 雇用関数
Chapter 21. The Theory of Prices
第２１章 物価の理論
Book VI Short Notes Suggested by the General Theory
第６巻 一般理論によって示唆される短いノート
Chapter 22. Notes on the Trade Cycle
第２２章 景気循環についてのノート
Chapter 23. Notes on Merchantilism, the Usury Laws, Stamped Money and Theories of Under-consumption
第２３章 重商主義、利子率制限法、スタンプ貨幣、過小消費論についてのノート
Chapter 24: Concluding Notes on the Social Philosophy towards which the General Theory might Lead
第２４章 一般理論が指し示す社会哲学についてのノート
“Whilst workers will usually resist a reduction of money-wages, it is
not their practice to withdraw their labour whenever there is a rise in
the price of wage-goods. It is sometimes said that it would be
illogical for labour to resist a reduction of money-wages but not to
resist a reduction of real wages. ... Moreover, the contention that the
unemployment which characterises a depression is due to a refusal by
labour to accept a reduction of money-wages is not clearly supported by
the facts. [Chapter 2]
Crisis of Keynesian Economics, Geoff Pilling, 1986
Marx and Keynes, Paul Mattick, 1939
Keynes Archive | M.I.A. | Political Economy Archive
John Maynard Keynes
The General Theory of Employment, Interest and Money
Preface
THIS book is chiefly addressed to my fellow economists. I hope that it
will be intelligible to others. But its main purpose is to deal with
difficult questions of theory, and only in the second place with the
applications of this theory to practice. For if orthodox economics is
at fault, the error is to be found not in the superstructure, which has
been erected with great care for logical consistency, but in a lack of
clearness and of generality in the premisses. Thus I cannot achieve my
object of persuading economists to re-examine critically certain of
their basic assumptions except by a highly abstract argument and also
by much controversy. I wish there could have been less of the latter.
But I have thought it important, not only to explain my own point of
view, but also to show in what respects it departs from the prevailing
theory. Those, who are strongly wedded to what I shall call “the
classical theory”, will fluctuate, I expect, between a belief that I am
quite wrong and a belief that I am saying nothing new. It is for others
to determine if either of these or the third alternative is right. My
controversial passages are aimed at providing some material for an
answer; and I must ask forgiveness if, in the pursuit of sharp
distinctions, my controversy is itself too keen. I myself held with
conviction for many years the theories which I now attack, and I am
not, I think, ignorant of their strong points.
The matters at issue are of an importance which cannot be exaggerated.
But, if my explanations are right, it is my fellow economists, not the
general public, whom I must first convince. At this stage of the
argument the general public, though welcome at the debate, are only
eavesdroppers at an attempt by an economist to bring to an issue the
deep divergences of opinion between fellow economists which have for
the time being almost destroyed the practical influence of economic
theory, and will, until they are resolved, continue to do so.
The relation between this book and my Treatise on Money, which I
published five years ago, is probably clearer to myself than it will be
to others; and what in my own mind is a natural evolution in a line of
thought which I have been pursuing for several years, may sometimes
strike the reader as a confusing change of view. This difficulty is not
made less by certain changes in terminology which I have felt compelled
to make. These changes of language I have pointed out in the course of
the following pages; but the general relationship between the two books
can be expressed briefly as follows. When I began to write my Treatise
on Money I was still moving along the traditional lines of regarding
the influence of money as something so to speak separate from the
general theory of supply and demand. When I finished it, I had made
some progress towards pushing monetary theory back to becoming a theory
of output as a whole. But my lack of emancipation from preconceived
ideas showed itself in what now seems to me to be the outstanding fault
of the theoretical parts of that work (namely, Books III and IV), that
I failed to deal thoroughly with the effects of changes in the level of
output. My so-called “fundamental equations” were an instantaneous
picture taken on the assumption of a given output. They attempted to
show how, assuming the given output, forces could develop which
involved a profit-disequilibrium, and thus required a change in the
level of output. But the dynamic development, as distinct from the
instantaneous picture, was left incomplete and extremely confused. This
book, on the other hand, has evolved into what is primarily a study of
the forces which determine changes in the scale of output and
employment as a whole; and, whilst it is found that money enters into
the economic scheme in an essential and peculiar manner, technical
monetary detail falls into the background. A monetary economy, we shall
find, is essentially one in which changing views about the future are
capable of influencing the quantity of employment and not merely its
direction. But our method of analysing the economic behaviour of the
present under the influence of changing ideas about the future is one
which depends on the interaction of supply and demand, and is in this
way linked up with our fundamental theory of value. We are thus led to
a more general theory, which includes the classical theory with which
we are familiar, as a special case.
The writer of a book such as this, treading along unfamiliar paths, is
extremely dependent on criticism and conversation if he is to avoid an
undue proportion of mistakes. It is astonishing what foolish things one
can temporarily believe if one thinks too long alone, particularly in
economics (along with the other moral sciences), where it is often
impossible to bring one's ideas to a conclusive test either formal or
experimental. In this book, even more perhaps than in writing my
Treatise on Money, I have depended on the constant advice and
constructive criticism of Mr. R. F. Kahn. There is a great deal in this
book which would not have taken the shape it has except at his
suggestion. I have also had much help from Mrs. Joan Robinson, Mr. R.
G. Hawtrey and Mr. R. F. Harrod, who have read the whole of the
proof-sheets. The index has been compiled by Mr. D. M. Bensusan-Butt of
King's College, Cambridge.
The composition of this book has been for the author a long struggle of
escape, and so must the reading of it be for most readers if the
author's assault upon them is to be successful,― a struggle of escape
from habitual modes of thought and expression. The ideas which are here
expressed so laboriously are extremely simple and should be obvious.
The difficulty lies, not in the new ideas, but in escaping from the old
ones, which ramify, for those brought up as most of us have been, into
every corner of our minds.
J. M. Keynes
December 13, 1935
序文 略
Book I Introduction
第１巻 序論
Chapter 1 The General Theory
第１章 一般的理論
I HAVE called this book the General Theory of Employment,
Interest and Money, placing the emphasis on the prefix general.The
object of such a title is to contrast the character of my arguments and
conclusions with those of the classical[1] theory of the subject, upon
which I was brought up and which dominates the economic thought, both
practical and theoretical, of the governing and academic classes of
this generation, as it has for a hundred years past.
私はこの本を「雇用、利子率、貨幣の一般的な理論」と名付けたが、力点は「一般的」という言葉に置いている。このような題名をつけたのは、私の議論と結論の性格が古典派[１]の経済理論の性格と大きく異なることを強調するためである。古典派の理論は私自身それで育ったものであるし、過去百年間と同じように今の世代の政界と学界の人たちの経済的な物の考え方を現実的にも理論的にも支配しているものである。
I shall argue that the postulates of the classical theory are
applicable to a special case only and not to the general case, the
situation which it assumes being a limiting point of the possible
positions of equilibrium. Moreover, the characteristics of the special
case assumed by the classical theory happen not to be those of the
economic society which we actually live, with the result that its
teaching is misleading and disastrous if we attempt to apply it to the
facts of experience.
私はこの古典派理論の公理が適用できるのは一般的な場合ではなく特殊な場合に限られていること、古典派の理論が想定する状況は、起こりうる均衡状況のうちでも極端なものであることを示すつもりである。さらに、古典派理論が想定するこの特殊な状況の様々な特徴は、我々が実際に生きている経済社会の特徴を反映せず、その結果、古典派理論の教えを経験的な事実に当てはめようとするとうまく行かずに失敗してしまうのである。
Author's Footnotes
[1]. “The classical economists” was a name invented by Marx to cover
Ricardo and James Mill and their predecessors, that is to say for the
founders of the theory which culminated in the Ricardian economics. I
have become accustomed, perhaps perpetrating a solecism, to include in
“the classical school” the followers of Ricardo, those, that is to say,
who adopted and perfected the theory of the Ricardian economics,
including (for example) J. S. Mill, Marshall, Edgeworth and Prof. Pigou.
著者注
[１]「古典派経済学者」という名前は、リカードとジェームズ・ミルとその先駆者たちを総称するためにマルクスによって作り出されたもので、リカード経済学に結実する経済理論の創始者たちを言うのである。ただし、私はやり過ぎかもしれないが、リカードの後継者たち、つまり、リカード経済学の理論を応用して完成させた学者たち、例えばJ.S.ミル（＝ジェームズ・ミルの子）、マーシャル、エッジワース、ピグー教授などの学者たちも「古典派」に含めるのを常としている。
Chapter 2 The Postulates of the Classical Economics
第２章 古典派経済学の公理
MOST treatises on the theory of value（価値、価格、値段、値） and production are
primarily concerned with the distribution of a given volume of employed
resources between different uses and with the conditions which,
assuming the employment of this quantity of resources, determine their
relative rewards and the relative values of their products.[1]
The question, also, of the volume of the available resources, in the
sense of the size of the employable population, the extent（広がり） of
natural wealth and the accumulated capital equipment, has often been
treated descriptively.
価格と生産の理論についての論文のほとんどは、主として、一定量の雇用された資源（＝ここでは人的資源）を様々な用途へ配分する仕方と、その量の資源を雇用すると想定する場合に、資源の相対的報酬と生産物の相対的価格を決定する条件に関するものである[１]。
利用可能な資源の量に関する問題もまた、雇用が可能な人口の規模と、天然の富の埋蔵量、資本設備の蓄積量という問題として、限定的に扱われてきたことはある。
But the pure theory of what determines the actual employment of the
available resources has seldom been examined in great detail. To say
that it has not been examined at all would, of course, be absurd. For
every discussion concerning fluctuations（変動） of employment, of which
there have been many, has been concerned with it. I mean, not that the
topic has been overlooked, but that the fundamental theory underlying
it has been deemed so simple and obvious that it has received, at the
most, a bare mention.[2]
しかしながら、利用可能な人的資源の実際の雇用を決めるものは何であるかに関する純粋な理論が詳細に検討されたことは殆どない。もちろん一度もないと言えば嘘になる。というのは、雇用の変動に関する議論は沢山あるし、そのいずれにおいてもこの問題は言及されている。私が言いたいのは、この問題がなおざりにされて来たと言うのではなく、この問題の基礎をなす根本原理があまりに単純明快なものと見なされて、せいぜい言及されるだけで終わってきたということである。[２]
I
The classical theory of employment ― supposedly simple and obvious ―
has been based. I think, on two fundamental postulates, though
practically without discussion, namely:
i. The wage is equal to the marginal product of labour（＝労働力の限界生産物）
That is to say, the wage of an employed person is equal to the value
which would be lost if employment were to be reduced by one unit (after
deducting（差し引く、控除する） any other costs which this reduction of output
would avoid); subject, however, to the qualification that the equality
may be disturbed, in accordance with certain principles, if competition
and markets are imperfect.
第１節
古典派の雇用理論、これまで単純明快だと見なされてきた理論は、私が思うに、ほとんど議論もされずに、次の二つの基本的な公理に基礎づけられている。
第一公理
「賃金は労働力の限界生産物（＝限界生産力）に等しい」（＝労働需要の公理）
即ち、被雇用者の賃金（＝例えば時給）は、雇用（＝労働力。第４章の定義で明らかになるように、雇用とは労働時間を意味する用語であって、雇用人数を意味しない）を１単位減少（＝１時間減少）させた場合に失われる価値（＝例えば売上）に等しい（この産出量の減少によって不要となる他の経費はあらかじめ差し引かれている）。ただし、この公理には、競争と市場が不完全な場合にはある種の原則に従ってこの等式の成立が妨げられる可能性がある、という但し書きがつく。
ii. The utility of the wage when a given volume of labour is employed
is equal to the marginal disutility of that amount of employment.
That is to say, the real wage of an employed person is that which is
just sufficient (in the estimation of the employed persons themselves)
to induce the volume of labour actually employed to be forthcoming;
subject to the qualification that the equality for each individual unit
of labour may be disturbed by combination between employable units
analogous to the imperfections of competition which qualify the first
postulate.
第二公理
「ある一定の労働力が雇用されているとき、賃金のもたらす効用（＝満足＝実質賃金）はその雇用（＝労働時間数）のもたらす限界不効用（＝追加の苦痛）に等しい」（＝実質賃金は労働量の限界不効用に等しい、ある賃金による満足は追加の労働時間による苦痛と等しい）（＝労働供給の公理。労働は苦痛なもの、賃金
は快いもの）
即ち、ある被雇用者の実質賃金とは、実際に雇用されるべき労働量を供給する気持ちにさせるのに（被雇用者の評価で）ちょうど充分な賃金のことである。ただし、不完全な競争が第一公理を阻害する可能性があるように、この等式は個別の労働単位にとっては、被雇用単位が団結した場合には成立しない可能性があるという但し書きがつく。
Disutility must be here understood to cover every kind of reason which
might lead a man, or a body of men, to withhold their labour rather
than accept a wage which had to them a utility below a certain minimum.
ここで言う不効用とは、ある人あるいはある団体が、自分たちに最低限以下の効用しかもたらさない賃金を受け入れるよりは、労働力を撤退しようと思わせる可能性のある全ての種類の理由を含んでいると解すべきである。
This postulate is compatible with what may be called 'frictional'
unemployment. For a realistic interpretation of it legitimately allows
for various inexactnesses of adjustment which stand in the way of
continuous full employment:
この公理はいわゆる「摩擦的失業」（＝自分に合った仕事をすぐに見つけられないために起きる失業）とは矛盾しない。というのは、現実的に解釈するなら、完全雇用の継続を妨げるさまざまな調整装置の不完全さは、まさにこの公理に含まれるからである。
for example, unemployment due to a temporary want of balance between
the relative quantities of specialised resources as a result of
miscalculation or intermittent demand; or to time-lags consequent on
unforeseen changes; or to the fact that the change-over from one
employment to another cannot be effected without a certain delay, so
that there will always exist in a non-static society a proportion of
resources unemployed 'between jobs'.
それは例えば、一時的に需要がなくなったり見込み違いのために専門職の人材量に偏りが出来た場合の失業であり、予期せぬ変化のためにタイミングが合わなかった場合の失業であり、一つの職から別の職へ変わるにはある程度時間がかかるのは仕方がないという事実による失業である。従って、動的な社会ではある程度の人的資源の転職による失業は必ず存在する。
In addition to 'frictional' unemployment, the postulate is also
compatible with 'voluntary' unemployment due to the refusal or
inability of a unit of labour, as a result of legislation or social
practices or of combination for collective bargaining or of slow
response to change or of mere human obstinacy, to accept a reward
corresponding to the value of the product attributable to its marginal
productivity.
この公理は「摩擦的失業」だけでなく「自発的失業」とも矛盾しない。「自発的失業」とは、法律や社会慣習、集団交渉のための団結、変化への対応の遅れ、単なる頑固さなどから、労働力の単位が「限界生産力」による製品の価格に応じた報酬の受取を拒否することによる失業である。
But these two categories of 'frictional' unemployment and 'voluntary'
unemployment are comprehensive. The classical postulates do not admit
of the possibility of the third category, which I shall define below as
'involuntary' unemployment.
ところが、この「摩擦的失業」と「自発的失業」というこの二つの分類が全ての失業なのである。古典派のこの公理には第三の分類の可能性は含まれないのだ。そして、これこそ私が「非自発的失業」として以下で説明していくものである。
Subject to these qualifications, the volume of employed resources is
duly determined, according to the classical theory, by the two
postulates. The first gives us the demand schedule for employment, the
second gives us the supply schedule; and the amount of employment is
fixed（決まる） at the point where the utility of the marginal product
balances the disutility of the marginal employment.
古典派経済理論によれば、雇用された人的資源の量は、上記のような但し書きがつきながらも、まさにこの二つの公理によって決定される。第一公理は雇用の需要グラフを提供し、第二公理は雇用の供給グラフを提供する。そして雇用労働の量は、「限界生産物の効用」（＝需要）と「労働力の限界不効用」（＝供給）が均衡する点で決まる。
It would follow from this that there are only four possible means of increasing employment:
(a) An improvement in organisation or in foresight which diminishes 'frictional' unemployment;
(b) a decrease in the marginal disutility of labour, as expressed by
the real wage for which additional labour is available, so as to
diminish 'voluntary' unemployment;
(c) an increase in the marginal physical productivity of labour in the
wage-goods industries (to use Professor Pigou's convenient term for
goods(財、物品) upon the price of which the utility of the
money-wage（賃金貨幣＝名目賃金） depends);
(d) an increase in the price of non-wage-goods compared with the price
of wage-goods, associated with a shift in the expenditure of
non-wage-earners from wage-goods to non-wage-goods.
This, to the best of my understanding, is the stance of Professor
Pigou's Theory of Unemployment ― the only detailed account of the
classical theory of employment which exists.[3]
このことから雇用を増大させる方法は４つしかないということになる。
（ア）「摩擦的失業」を減らすために予測の進歩と施設の改善。
（イ）「自発的失業」を減らすために、労働力の追加が可能となるような実質賃金によって表わされた「労働力の限界不効用」を減らす（＝賃金を下げる）。
（ウ）賃金財（wage-goods＝一般消費財、労働者の消費財、資本財と投資財の対語）の製造業における労働力の物理的な限界生産力の上昇（賃金財というピグー教授の便利な言葉を使わせてもらう。名目賃金の効用はその賃金で購入する賃金財の価格によって決まる）。
（エ）非賃金労働者の支出を賃金財から非賃金財（＝贅沢品や嗜好品、投資財）に移しながら、賃金財の価格に比べた非賃金財の価格を上昇させる。
これが、私の理解する限りにおける、ピグー教授の『失業理論』の主張であり、この理論だけが現在存在する唯一の古典派による詳細な雇用理論である[３]。
II
Is it true that the above categories are comprehensive in view
of the fact that the population generally is seldom doing as much work
as it would like to do on the basis of the current（現行、当期、経常、流通、当座、流動）
wage? For, admittedly, more labour would, as a rule, be forthcoming at
the existing money-wage if it were demanded.[4]
第２節
現行の賃金のもとで人びとが欲しいだけの仕事を見つけることなど殆ど不可能なのが現実なのに、「摩擦的失業」と「自発的失業」の二つの分類に全ての失業が含まれるなどということが真実だろうか。というのは、需要さえあれば、普通は当然現行の名目賃金のもとでもっと沢山の労働力が供給可能だからである[４]。
The classical school reconcile this phenomenon with their second
postulate by arguing that, while the demand for labour at the existing
money-wage may be satisfied before everyone willing to work at this
wage is employed, this situation is due to an open or tacit agreement
amongst workers not to work for less, and that if labour as a whole
would agree to a reduction of money-wages more employment would be
forthcoming. If this is the case, such unemployment, though apparently
involuntary, is not strictly so, and ought to be included under the
above category of 'voluntary' unemployment due to the effects of
collective bargaining, etc.
古典派はこの現象を第二公理と合わせるために、現行の名目賃金で働く意欲のある人が全員雇われる前にその賃金での労働力の需要が満たされてしまうことがあ
るとしても、労働者たちはそれ以下の賃金では働かないという公然あるいは暗黙の了解があるためにこのような状況になるのであり、労働者側がこぞって名目賃金の引き下げに同意すれば、もっと多くの雇用が生まれると言うのである。もしそうだとするなら、そのような失業は「非自発的」に見えるとしても、厳密にはそうではないことになり、団体交渉などの結果である「自発的失業」という上記の分類に含められることになる。
This calls for two observations, the first of which relates to the
actual attitude of workers towards real wages and money-wages
respectively and is not theoretically fundamental, but the second of
which is fundamental.
しかし、これに対しては二つのことを言わなければならない。一つ目は実質賃金と名目賃金のそれぞれに対する労働者の実際の態度に関するもので、理論上はそれほど本質的なことではない。むしろ、その後の、二つ目のほうが本質的である。
Let us assume, for the moment, that labour is not prepared to work for
a lower money-wage and that a reduction in the existing level of
money-wages would lead, through strikes or otherwise, to a withdrawal
from the labour market of labour which is now employed.
いま仮に、労働者側が現行より低い名目賃金では働く気がないと仮定しよう。つまり、現行の名目賃金レベルを引き下げた場合には、労働者側はストライキなどの手段を通じて、現在雇用されている労働力を労働市場から撤退すると仮定しよう。
Does it follow from this that the existing level of real wages
accurately measures the marginal disutility of labour? Not necessarily.
For, although a reduction in the existing money-wage would lead to a
withdrawal of labour, it does not follow that a fall in the value of
the existing money-wage in terms of wage-goods would do so, if it were
due to a rise in the price of the latter.
このことは（＝第二公理が言うように）現行の実質賃金レベルがまさに「労働力の限界不効用」を表していることになるだろうか。必ずしもそうとは言えまい。というのは、現行名目賃金の引き下げが労働力の撤退に至ることはあっても、現行名目賃金を賃金財で測った価値（＝実質賃金）が賃金財の価格（＝物価）の上
昇によって下落した場合でも労働力の撤退を引き起こすとは言えないからである。
In other words, it may be the case that within a certain range
the demand of labour is for a minimum money-wage and not for a minimum
real wage. The classical school have tacitly assumed that this would
involve no significant change in their theory. But this is not so. For
if the supply of labour is not a function of real wages as its sole
variable, their argument breaks down entirely and leaves the question
of what the actual employment will be quite indeterminate.[5] They do
not seem to have realised that, unless the supply of labour is a
function of real wages alone, their supply curve for labour will shift
bodily with every movement of prices（物価）. Thus their method is tied up
with their very special assumptions, and cannot be adapted to deal with
the more general case.
言い換えれば、恐らく実情は一定の範囲内で労働者側が求めるのは最低名目賃金の引き上げであって、最低実質賃金の引き上げではないのである。古典派はこのことが自分たちの理論に大きな違いをもたらさないことを暗黙裡に想定している。しかし、名目か実質かには大きな違いがある。というのは、もし労働力の供給が実質賃金をその唯一の変数とする関数でないなら、彼らの理論は完全に破綻してしまい、現実の雇用労働力の到達点はまったく不定になってしまうからである[５]。もし労働力の供給が実際に実質賃金（＝物価変動の影響を受けない）のみの関数でないなら、古典派の労働力供給曲線は物価の変動のたびに全体がシフトしてしまうが、そのことを彼らは理解していないと思われる。したがって、彼らの方法は彼ら自身の非常に特殊な想定と結びついているのであり、もっと一般的な場合に応用することは出来ないのである。
Now ordinary experience tells us, beyond doubt, that a situation where
labour stipulates (within limits) for a money-wage rather than a real
wage, so far from being a mere possibility, is the normal case. Whilst
workers will usually resist a reduction of money-wages, it is not their
practice to withdraw their labour whenever there is a rise in the price
of wage-goods. It is sometimes said that it would be illogical for
labour to resist a reduction of money-wages but not to resist a
reduction of real wages. For reasons given below (section III), this
might not be so illogical as it appears at first; and, as we shall see
later, fortunately so. But, whether logical or illogical, experience
shows that this is how labour in fact behaves.
ところで、労働者側が要求するのが（限度はあるが）実質賃金ではなく名目賃金であるというのは、単なる可能性であるどころか通常のことである。それは疑いもなく我々は日常体験から明らかである。ふつう労働者側は名目賃金の引き下げには抵抗するが、賃金財の価格が上昇（＝実質賃金の低下）するたびに労働力を撤退するようなことはしないものである。労働者側が名目賃金の引き下げに抵抗するのに実質賃金の引き下げに抵抗しないのは不合理だと時々言われる。しかし、このことは以下（次の３節）にあげる理由から、見かけほど不合理ではないかもしれないのである。それどころか、後に見るように、彼らのこの一見不合理な行動が幸いしているのだ。しかしながら、不合理であるか否かに関わらず、労働者側がこのように振舞うことは我々の日頃の経験から明らかである。
Moreover, the contention that the unemployment which characterises a
depression is due to a refusal by labour to accept a reduction of
money-wages is not clearly supported by the facts. It is not very
plausible to assert that unemployment in the United States in 1932 was
due either to labour obstinately refusing to accept a reduction of
money-wages or to its obstinately demanding a real wage beyond what the
productivity of the economic machine was capable of furnishing. Wide
variations are experienced in the volume of employment without any
apparent change either in the minimum real demands of labour or in its
productivity. Labour is not more truculent in the depression than in
the boom ― far from it. Nor is its physical productivity less. These
facts from experience are a prima facie（明らかな） ground for questioning
the adequacy of the classical analysis.
さらに、不況の特徴である失業の原因は労働者側が名目賃金の引き下げを受け入れないことにあるとする主張はそれほど明確な事実の裏付けをもっているとは言えない。１９３２年の米国に見られた失業の原因は、労働者側が名目賃金の引き下げを頑固に拒否したからであるとか、経済マシーンの生産性が提供できる以上の実質賃金を頑固に要求したからであるという主張はもっともらしくない。我々は雇用量の大幅な変動を経験したが、その間、労働者側が要求する最低実質賃金にも労働生産性にも明らかな変化はなかったのである。不況の時の労働者側は好況の時ほど戦闘的ではない。むしろ大人しいほどだ。また物理的な生産性も低下はしないものである。経験から得たこのような事実は、古典派の分析の妥当性を疑う明白な根拠となる。
It would be interesting to see the results of a statistical
enquiry into the actual relationship between changes in money-wages and
changes in real wages. In the case of a change peculiar to a particular
industry one would expect the change in real wages to be in the same
direction as the change in money-wages. But in the case of changes in
the general level of wages, it will be found, I think, that the change
in real wages associated with a change in money-wages, so far from
being usually in the same direction, is almost always in the opposite
direction. When money-wages are rising, that is to say, it will be
found that real wages are falling; and when money-wages are falling,
real wages are rising. This is because, in the short period, falling
money-wages and rising real wages are each, for independent reasons,
likely to accompany decreasing employment; labour being readier to
accept wage-cuts when employment is falling off, yet real wages
inevitably rising in the same circumstances on account of the
increasing marginal return to a given capital equipment when output is
diminished.
ここで名目賃金の変動と実質賃金の変動との関係の統計的調査結果を見ると面白いかもしれない。個別の産業に特有の賃金変動の場合には、実質賃金の変化と名目賃金の変化は同じ方向に向かうことが予想される。しかし、全般的な賃金レベルの変動の場合には、名目賃金の変化にともなう実質賃金の変化は通常同じ方向に向かうどころか殆ど常に逆方向に向かうのが見出されるはずだ。つまり、名目賃金が上昇するときには実質賃金が下落しているのが見られ、名目賃金が下落するときには実質賃金が上昇しているのが見られるだろう。これは何故かというと、短期では、名目賃金の低下と実質賃金の上昇はそれぞれ独自の理由で失業の増加を伴って起きるからである。つまり、失業が増加すれば労働者側は賃金カット（＝名目賃金の下落）を受け入れやすくなるが、同じ状況において、産出量が低下すると現状の資本設備に対する「限界収益」が上昇する（＝収益逓減の法則の逆）ため、実質賃金は必然的に上昇するのである。
If, indeed, it were true that the existing real wage is a
minimum below which more labour than is now employed will not be
forthcoming in any circumstances, involuntary unemployment, apart from
frictional unemployment, would be non-existent. But to suppose that
this is invariably the case would be absurd. For more labour than is at
present employed is usually available at the existing money-wage, even
though the price of wage-goods is rising and, consequently, the real
wage falling. If this is true, the wage-goods equivalent of the
existing money-wage is not an accurate indication of the marginal
disutility of labour, and the second postulate does not hold good.
確かに、もし現行の実質賃金は、それ以下では今より多くの労働力が供給されることは全くない最低レベルのものだ（＝第二公理）というのが本当ならば、「摩擦的失業」以外には「非自発的失業」はありえないことになる。しかし、実質賃金が最低レベルであればいつもこうだと考えるのはおかしい。たとえ賃金財の価格（＝物価）が上昇してその結果実質賃金が下落しても、現在雇われているよりも多くの労働力が現行名目賃金で供給可能なことはよくあるからである。そして、もしこれが事実なら、現行名目賃金に相当する賃金財（＝実質賃金）は、「労働力の限界不効用」を正確に表していないことになり、第二公理は有効性を失う。
But there is a more fundamental objection. The second postulate flows
from the idea that the real wages of labour depend on the wage bargains
which labour makes with the entrepreneurs. It is admitted, of course,
that the bargains are actually made in terms of money（名目の）, and even
that the real wages acceptable to labour are not altogether independent
of what the corresponding money-wage happens to be. Nevertheless it is
the money-wage thus arrived at which is held to determine the real
wage. Thus the classical theory assumes that it is always open to
labour to reduce its real wage by accepting a reduction in its
money-wage. The postulate that there is a tendency for the real wage to
come to equality with the marginal disutility of labour clearly
presumes that labour itself is in a position to decide the real wage
for which it works, though not the quantity of employment（雇用量）
forthcoming at this wage.
しかし、もっと根本的反論がある。第二公理は、実質賃金は労働者側が企業家との間で行う賃金交渉によって決まるという考え方から来ている。もちろん、確かに、この交渉が実際に名目賃金について行われたものであっても、労働者側が受け入れ可能な実質賃金がそれに対応する名目賃金と全然無関係ということはない。それでもこうして決められるのは名目賃金であって、それが実質賃金を決めると考えられているのだ。つまり、古典派の理論では、労働者側は名目賃金の引き下げを受け入れることでいつでも自由に実質賃金を引き下げることができると考えられているのである。実質賃金は「労働力の限界不効用」と等しくなる傾向があるとする公理には、あきらかに、労働者側が自分たちの仕事に対する実質賃金を決める立場にあるとする想定があるのだ。もっとも、その実質賃金で生まれる雇用量を労働者側が決めることは出来ないが。
The traditional theory maintains, in short, that the wage bargains
between the entrepreneurs and the workers determine the real wage; so
that, assuming free competition amongst employers（使用者） and no
restrictive combination amongst workers, the latter can, if they wish,
bring their real wages into conformity with the marginal disutility of
the amount of employment（＝労働量） offered by the employers at that wage.
If this is not true, then there is no longer any reason to expect a
tendency towards equality between the real wage and the marginal
disutility of labour.
要するに、伝統的理論は、企業家と労働者たちの間の賃金交渉が決めるのは実質賃金であると主張する。そして、使用者間の自由な競争が維持され、労働者たちの団結に妨害されなければ、労働者たちは望みさえすれば、自分たちの実質賃金を、その賃金のもとで使用者が提供する雇用量の限界不効用に一致させることが出来るというのである。もし労働者にこれが出来ないなら、その場合には、実質賃金と労働力の限界不効用が一致する傾向を予想するどんな理由もなくなってしまうのである。
The classical conclusions are intended, it must be remembered, to apply
to the whole body of labour and do not mean merely that a single
individual can get employment by accepting a cut in money-wages which
his fellows refuse. They are supposed to be equally applicable to a
closed system as to an open system, and are not dependent on the
characteristics of an open system or on the effects of a reduction of
money-wages in a single country on its foreign trade, which lie, of
course, entirely outside the field of this discussion. Nor are they
based on indirect effects due to a lower
wages-bill（賃金費用の総額、企業が被雇用者に支払う全金額） in terms of money（名目の） having
certain reactions on the banking system and the state of
credit（銀行の貸出状況、信用の状態）, effects which we shall examine in detail in
Chapter 19. They are based on the belief that in a closed system a
reduction in the general level of money-wages will be accompanied, at
any rate in the short period and subject only to minor qualifications,
by some, though not always a proportionate, reduction in real wages.
ここで忘れてならないのは、古典派理論の様々な結論は労働者側の全体に当てはまるとされており、単に仲間が拒否する名目賃金の引き下げを誰かある個人が受け入れたら雇用されると言っているのではないということである。しかも古典派の理論は、閉鎖経済だけでなく開放経済にも同じように当てはまるものであり、我々の議論からは埒外の開放経済の特質や、ある国の名目賃金の引き下げがその海外貿易に及ぼす効果などに左右されものではないというのである。また、古典派の結論は、名目の賃金費用の総額が減少した場合に銀行や金融市場に与える影響に起因する間接的な効果にも左右されるものでもない。この効果については１９章で詳しく検討するだろう。古典派の結論は、閉鎖経済においては、全般的な名目賃金レベルの引き下げがあったときには、少なくとも短期においてわずかの条件さえ整えば、それと同時に実質賃金も、同程度ではないとしても、いくらかは下がるはずだという信念に基づいているのである。
Now the assumption that the general level of real wages depends on the
money-wage bargains between the employers and the workers is not
obviously true. Indeed it is strange that so little attempt should have
been made to prove or to refute it. For it is far from being consistent
with the general tenor of the classical theory, which has taught us to
believe that prices（物価、価格） are governed by marginal
prime-cost（主要費用＝要素費用＋使用費用＝直接費＝可変費用） in terms of money and that
money-wages largely govern marginal prime-cost. Thus if money-wages
change, one would have expected the classical school to argue that
prices would change in almost the same proportion, leaving the real
wage and the level of unemployment practically the same as before, any
small gain or loss to labour being at the expense or profit of other
elements of marginal cost（限界費用） which have been left unaltered.[6]
ところで、全般的な実質賃金レベルが使用者と労働者たちの間の名目賃金の交渉によって決まるという想定は、明白な事実ではない。実際、不思議なことに、この想定の証明も反証も殆ど行われたことがないのである。というのは、この想定は、商品の価格は名目の限界主要費用（＝主要費用はここが初出、元々マーシャルの用語で主要費用と補足費用で「総費用」になる。「価格は限界費用に等しい」）によって決まり、限界主要費用は主として名目賃金によって決まると我々に信じこませてきた古典派理論の全体的な趣旨とまったく一致しないからである。この趣旨によれば、もし名目賃金に変更があれば、殆ど同じ割合で商品の価格も変化するから、実質賃金と失業率は以前と殆ど変わることはなく（＝貨幣数量説）、労働者の多少の得失はこれまで変わることのなかった限界費用（＝価格）の他の要素の損得と相殺されると、古典派の学者たちなら主張するだろうと誰もが予想するはずである[６]。
They seem, however, to have been diverted from this line of thought,
partly by the settled conviction that labour is in a position to
determine its own real wage and partly, perhaps, by preoccupation with
the idea that prices depend on the quantity of money. And the belief in
the proposition that labour is always in a position to determine its
own real wage, once adopted, has been maintained by its being confused
with the proposition that labour is always in a position to determine
what real wage shall correspond to full employment, i.e. the maximum
quantity of employment which is compatible with a given real wage.
ところが、彼らはこの考え方の方向から逸脱してしまったように思われる。それは一方では労働者側は常に自分たちの実質賃金を決定できる立場にあるとの固い信念のためであり、また一方では物価は貨幣量によって決まるという固定観念のためである。そして、労働者が常に自分の実質賃金を決定できるという考え方が信じられて捨てられなかったのは、この考え方と、労働者側が常に完全雇用（つまり実質賃金と両立する雇用の最大値）に対応する実質賃金を決められるとする考え方とを混同したからである。
To sum up: there are two objections to the second postulate of the
classical theory. The first relates to the actual behaviour of labour.
A fall in real wages due to a rise in prices, with money-wages
unaltered, does not, as a rule, cause the supply of available labour on
offer at the current wage to fall below the amount actually employed
prior to the rise of prices. To suppose that it does is to suppose that
all those who are now unemployed though willing to work at the current
wage will withdraw the offer of their labour in the event of even a
small rise in the cost of living. Yet this strange supposition
apparently underlies Professor Pigou's Theory of Unemployment,[7] and
it is what all members of the orthodox school are tacitly assuming.
以上まとめると、古典派の第二公理に対しては二つの反論がある。第一は、労働者側の実際の行動に関するものである。名目賃金が変わらない状況で物価上昇に
よって実質賃金が下がっても、基本的に、現行賃金のもとで供給されている労働力が物価上昇以前の雇用量より下がることはない。それなのに、物価の上昇で労働供給が下がると考えるのは、労働意欲があるのに現行賃金で雇用されていない人は物価が少し上がっても労働力を供給する意思を撤回すると考えるのと同じである。しかしながら、この奇妙な考え方がピグー教授の『失業理論』の根底に横たわっているようである。[７]。そしてこのことは伝統学派の全ての仲間が暗黙のうちに想定していることである。
But the other, more fundamental, objection, which we shall develop in
the ensuing chapters, flows from our disputing the assumption that the
general level of real wages is directly determined by the character（人物）
of the wage bargain. In assuming that the wage bargain determines the
real wage the classical school have slipt（＜slip）in an illicit
assumption. For there may be no method available to labour as a whole
whereby it can bring the general level of money-wages into conformity
with the marginal disutility of the current volume of employment. There
may exist no expedient by which labour as a whole can reduce its real
wage to a given figure by making revised money bargains with the
entrepreneurs. This will be our contention. We shall endeavour to show
that primarily it is certain other forces which determine the general
level of real wages. The attempt to elucidate this problem will be one
of our main themes. We shall argue that there has been a fundamental
misunderstanding of how in this respect the economy in which we live
actually works.
しかし、もう一つのもっと重要な反論は、以下の章でもっと詳しく扱うが、全般的な実質賃金レベルが賃金交渉の当事者によって直接決定されるという想定に対するものである。賃金交渉によって実質賃金が決まるという古典派の想定は間違っている。というのは、全体として労働者側が名目賃金の全般的なレベルを現行の雇用量の「限界不効用」に一致させる方法など存在しないからである。いやそもそも、企業家との賃金交渉を作り変えて全体として労働者側が実質賃金を特定の値まで減らせるような都合のいい方法はないのである。これが我々の主張である。我々は全般的な実質賃金レベルを主として決定しているのはもっと別の要因であることを明らかにしようと思う。この問題の解決が我々の主要テーマの一つとなる。我々の現実の生活を支える経済がこの点でどのように機能しているかについて本質的な誤解があると我々は主張していくつもりである。
III
Though the struggle over money-wages between individuals and groups is
often believed to determine the general level of real wages, it is, in
fact, concerned with a different object.Since there is imperfect
mobility of labour, and wages do not tend to an exact equality of net
advantage（利益） in different occupations, any individual or group of
individuals, who consent to a reduction of money-wages relatively to
others, will suffer a relative reduction in real wages, which is a
sufficient justification for them to resist it.
第３節
個人の間や団体の間の名目賃金についての争いが全般的な実質賃金レベルを決めている（＝実質賃金が高止まりして完全雇用を阻害している）としばしば信じられているが、実際にはそれはもっと別の目的の争いなのである。労働力の流通は不完全であり、賃金は異なる職業の純利益を正確に均等化する方向へは向かわないので、ある個人または団体が名目賃金をほかと比べて相対的に引き下げることに同意すれば、実質賃金も相対的に引き下げることになってしまう。だから、彼らが名目賃金の引き下げを拒否するのは充分正当なことなのである。
On the other hand it would be impracticable to resist every
reduction of real wages, due to a change in the purchasing-power of
money which affects all workers alike; and in fact reductions of real
wages arising in this way are not, as a rule, resisted unless they
proceed to an extreme degree. Moreover, a resistance to reductions in
money-wages applying to particular industries does not raise the same
insuperable bar to an increase in aggregate employment（総雇用、集計雇用）, which
would result from a similar resistance to every reduction in real wages.
その一方で、実質賃金の低下（＝インフレ）を労働者がいちいち拒否（＝賃上げ闘争によって）するのは不可能である。実質賃金の低下は貨幣の購買力の低下によって起こるもので、全労働者に同じように影響するからである。実際、このようにして発生した実質賃金の低下は、それが極端に進行しない限り普通は労働者に受け入れられる。さらに、特定の産業で起きた名目賃金の引き下げに対する抵抗なら、総雇用の増加にはたいした障碍にならないが、もし全ての実質賃金の低下に対して労働者がことごとく抵抗するなら、総雇用の増加への乗り越えがたい障碍となってしまうだろう。
In other words, the struggle about money-wages primarily affects
the distribution of the aggregate（総、集計） real wage between different
labour-groups, and not its average amount per unit of employment, which
depends, as we shall see, on a different set of forces. The effect of
combination on the part of a group of workers is to protect their
relative real wage. The general level of real wages depends on the
other forces of the economic system.
言い換えれば、名目賃金についての争いは総実質賃金の異なる労働者の団体の間での分配に対して主に影響するが、雇用労働１単位あたりの実質賃金の平均値には影響しないのである。後者は後に見るように別の要因に左右される。労働者グループが団結する効果は、自分たちの相対的な実質賃金を守れることである。全般的な実質賃金レベルは、経済のまた別の要因に左右される。
Thus it is fortunate that the workers, though unconsciously, are
instinctively more reasonable economists than the classical school,
inasmuch as they resist reductions of money-wages, which are seldom or
never of an all-round character（＝大幅な、全般的な）, even though the existing
real equivalent of these wages exceeds the marginal disutility of the
existing employment; whereas they do not resist reductions of real
wages, which are associated with increases in aggregate employment and
leave relative money-wages unchanged, unless the reduction proceeds so
far as to threaten a reduction of the real wage below the marginal
disutility of the existing volume of employment.
つまり、幸いなことに労働者たちは無意識ではあるが本能的に古典派の学者たちよりも分別のある経済学者なのだ。というのは、たとえ現行の名目賃金の実質的な等価物（＝実質賃金）が現行の雇用労働力の「限界不効用」を超えて（＝苦痛を補って余りある）いても、彼らは名目賃金のけっして全般的ではない引き下げにも抵抗するが、その一方、実質賃金の低下が進行して現行雇用労働力の「限界不効用」より下回るところまで来ない限り、労働者たちは（＝第二公理に反して）実質賃金の低下には抵抗しないので、その結果、相対的な名目賃金は変わらないままで総雇用は増加するのである。
Every trade union will put up some resistance to a cut in money-wages,
however small. But since no trade union would dream of striking on
every occasion of a rise in the cost of living, they do not raise the
obstacle to any increase in aggregate employment which is attributed to
them by the classical school.
たとえ少額でも名目賃金のカットに対しては、どの労働組合も抵抗してみせるものである。しかし、物価の上昇（＝実質賃金の低下）のたびにストライキを打とうとするような労働組合は存在しない。したがって、古典派の学者は労働組合が（＝賃金引下げに抵抗して）総雇用の増加を妨害していると言うが、そんなことはないのである。
IV
We must now define the third category of unemployment, namely
'involuntary' unemployment in the strict sense, the possibility of
which the classical theory does not admit.
Clearly we do not mean by 'involuntary' unemployment the mere existence
of an unexhausted capacity to work. An eight-hour day does not
constitute unemployment because it is not beyond human
capacity（人間の能力を超えていない） to work ten hours. Nor should we regard as
'involuntary' unemployment the withdrawal of their labour by a body of
workers because they do not choose to work for less than a certain real
reward. Furthermore, it will be convenient to exclude 'frictional'
unemployment from our definition of 'involuntary' unemployment.
第４節
我々はいまや失業の三つ目の分類、古典派の理論がそんなものはあり得ないと言っている「非自発的失業」の厳密な定義をしなければならない。
我々の言う「非自発的失業」が単なる使いきっていない労働力の存在でないのは明らかである。人間は一日に１０時間働く能力があるからといって８時間労働が失業になるわけではないのだ。また、ある労働者の団体が一定の実質所得以下では働きたくないとして労働力を撤回することを「非自発的失業」とみなすべきではない。さらには、「摩擦的失業」を我々の「非自発的失業」の定義から除外するほうが便利だろう。
My definition is, therefore, as follows: Men are involuntarily
unemployed if, in the event of a small rise in the price of wage-goods
relatively to the money-wage, both the aggregate supply of labour
willing to work for the current money-wage and the aggregate demand for
it at that wage would be greater than the existing volume of
employment. An alternative definition, which amounts, however, to the
same thing, will be given in the next chapter (p. 26 below).
すると、私の定義は次のようになる。名目賃金に比べた賃金財価格の少しの上昇（＝実質賃金の低下）によって、現行の名目賃金で働く意思のある労働力の総供給（＝集計供給、総労働供給）と、その賃金での労働力の総需要（＝集計需要、総労働需要）の双方が、ともに当期の雇用労働の量より大きくなっているのに失業している人を「非自発的失業者」というのである（＝実質賃金が下がって求人が増えて、名目賃金は同じなので求職は増えているのに、現実には失業している状態を非自発的失業という）。もっとも、次の章では同じことを意味するもう一つの定義（＝有効需要不足により失業）が与えられるだろう。
It follows from this definition that the equality of the real
wage to the marginal disutility of employment presupposed by the second
postulate, realistically interpreted, corresponds to the absence of
'involuntary' unemployment. This state of affairs we shall describe as
'full' employment, both 'frictional' and 'voluntary' unemployment being
consistent with 'full” employment thus defined. This fits in, we shall
find, with other characteristics of the classical theory, which is best
regarded as a theory of distribution in conditions of full employment.
この定義に従えば、実質賃金は雇用労働力の限界不効用に等しいという第二公理は、現実に当てはめると「非自発的失業」が存在しない状態に対応することになる。この状態を我々は「完全雇用」と呼ぶことにする（■）。このように定義した場合の「完全雇用」は、「摩擦的失業」とも「自発的失業」とも両立するからである。このことは、後に見るように、古典派理論の他の特徴とも符合する。古典派理論は「完全雇用」状態での配分理論と見るのが最善なのである。
So long as the classical postulates hold good, unemployment, which is
in the above sense involuntary, cannot occur. Apparent unemployment
must, therefore, be the result either of temporary loss of work of the
'between jobs' type or of intermittent demand for highly specialised
resources or of the effect of a trade union 'closed shop' on the
employment of free labour.
古典派の二つの公理が有効である限りでは、上記の意味での「非自発的失業」は起こりようがない。したがって、見かけ上の失業は、転職による一時的な失業の結果か、高度の専門職の人材に対する需要が一時的になくなったためか、クローズドショップ制（＝労働組合員だけが雇用される）が非組合員の雇用に及ぼす影響のせいである。
Thus writers in the classical tradition, overlooking the special
assumption underlying their theory, have been driven inevitably to the
conclusion, perfectly logical on their assumption, that apparent
unemployment (apart from the admitted exceptions) must be due at bottom
to a refusal by the unemployed factors to accept a reward which
corresponds to their marginal productivity.
こうして、古典的伝統のもとにある学者たちは、自分たちの理論の根底にある特殊な想定（＝労働者が賃金交渉で実質賃金を決めているとする想定）を見落としているので、見かけ上の失業の根本的な原因は（自ら認める例外を除いて）雇用されていない生産要素（＝失業者）が自分たちの「限界生産力」に合った報酬（＝第一公理、労働需要の公理）の受け入れを拒否するからだ（＝自発的失業、既出）という、彼らの考えでは完璧に論理的な結論に至らざるを得ないのである。
A classical economist may sympathise with labour in refusing to accept
a cut in its money-wage, and he will admit that it may not be wise to
make it to meet conditions which are temporary; but scientific
integrity forces him to declare that this refusal is, nevertheless, at
the bottom of the trouble.
古典派経済学者も、労働者が名目賃金の引き下げを拒否することには同情するし、一時的な条件の変化に名目賃金を合わせることが賢明でないことも認めている。しかし、それにも関わらず、科学者としての潔癖さゆえに彼らは、この労働者の賃下げ拒否こそ問題の根本原因であると表明せざるを得ないのである。
Obviously, however, if the classical theory is only applicable to the
case of full employment, it is fallacious to apply it to the problems
of involuntary unemployment ― if there be such a thing (and who will
deny it?). The classical theorists resemble Euclidean geometers in a
non-Euclidean world who, discovering that in experience straight lines
apparently parallel often meet, rebuke the lines for not keeping
straight as the only remedy for the unfortunate collisions which are
occurring. Yet, in truth, there is no remedy except to throw over the
axiom of parallels and to work out a non-Euclidean geometry. Something
similar is required today in economics. We need to throw over the
second postulate of the classical doctrine and to work out the
behaviour of a system（＝system of a behaviour） in which involuntary
unemployment in the strict sense is possible.
しかしながら、もし古典派理論が完全雇用状態にしか適用できないものなら、そしてもし「非自発的失業」が存在するなら（誰がそれを否定するだろうか）、この非自発的失業という問題に古典派理論を適用するのは明らかに間違っている。古典派の学者は非ユークリッド世界のなかのユークリッド幾何学者に似ている。彼らは見かけ上は平行な２直線がしばしば交わることを経験上見出しても、２直線の不幸な交わりが起こるのを正すには線をまっすぐ保つしかないのにそうしないのが悪いと言うのだ。しかし実際には、平行線の公理を捨てて非ユークリッド幾何学を構築するしか解決方法はないのである。同様のことが現在の経済学にも求められている。我々は古典派経済学の第二公理を捨てて、「非自発的失業」が厳密な意味で可能となるような経済行動の体系を構築する必要がある。
V
In emphasising our point of departure from the classical system,
we must not overlook an important point of agreement. For we shall
maintain the first postulate as heretofore, subject only to the same
qualifications as in the classical theory; and we must pause, for a
moment, to consider what this involves.
第５節
我々は古典派の体系からの決別を強調するあまりに、彼らと同意できる重要な点を見過ごすべきではない。というのは、第一公理の方は、これまで同様、古典派理論と同じ但し書きに従うだけで、我々はこれを保持しつづけるからである。しばらく間、我々はこの公理の内容を検討しなくてはならない。
It means that, with a given organisation, equipment and
technique, real wages and the volume of output (and hence of
employment) are uniquely（ただ一つの、独自の、一意の） correlated, so that, in
general, an increase in employment can only occur to the accompaniment
of a decline in the rate of real wages. Thus I am not disputing this
vital fact which the classical economists have (rightly) asserted as
indefeasible. In a given state of organisation, equipment and
technique, the real wage earned by a unit of labour has a unique
(inverse) correlation with the volume of employment. Thus if employment
increases, then, in the short period, the reward per unit of labour in
terms of wage-goods must, in general, decline and profits increase.[8]
この公理（＝労働需要の公理）の意味するところは、組織と設備と技術を一定とした場合、実質賃金と産出量（つまり雇用労働の量）は一意的な相関関係にある
ので、一般に雇用の増加は実質賃金率の低下に伴ってのみ起こりうる（＝右下がりのグラフ）というものである。そして、古典派経済学者が論駁の余地がないとまさに主張するこの枢要な事実に関して、私は異議を唱えるつもりはない。組織と設備と技術を一定とした場合、１単位の労働によって得られる実質賃金は、雇用量と一意の（負の）相関関係（＝右下がりのグラフ）にある。つまり、短期においては、雇用が増加すれば、賃金財（＝物価）で測った労働１単位あたりの報酬（＝実質賃金）は一般に低下して、利潤（＝企業家の）は増加するのである。[８]
This is simply the obverse（反面） of the familiar proposition that
industry is normally working subject to decreasing returns in the short
period during which equipment etc. is assumed to be constant; so that
the marginal product in the wage-good industries (which governs real
wages) necessarily diminishes as employment is increased. So long,
indeed, as this proposition holds, any means of increasing employment
must lead at the same time to a diminution of the marginal product and
hence of the rate of wages measured in terms of this product.
これは、産業は短期において設備その他を一定とした場合には普通は「収益逓減の法則」に従うとする有名な法則の単なる裏返しである。その結果、雇用労働力が増大するに従って、賃金財産業の「限界生産物」（これが実質賃金を決める）は必然的に減少するのである。事実、この法則が有効な限り、雇用を増やすために何をしようと、それは必ず限界生産物の減少に、ひいては、この生産物によって測った賃金率の低下を招くのである。
But when we have thrown over the second postulate, a decline in
employment, although necessarily associated with labour's receiving a
wage equal in value to a larger quantity of wage-goods, is not
necessarily due to labour's demanding a larger quantity of wage-goods;
and a willingness on the part of labour to accept lower money-wages is
not necessarily a remedy for unemployment. The theory of wages in
relation to employment, to which we are here leading up, cannot be
fully elucidated, however, until Chapter 19 and its Appendix have been
reached.
しかしながら、もし我々が第二公理（＝労働者側は実質賃金を要求して手に入れる）を放棄するなら、より多くの賃金財に匹敵する価値の賃金（＝より多くの実質賃金）を労働者が受け取ることに伴って必然的に雇用が減少する（＝第一公理）けれども、この減少の原因は必ずしも労働者が賃金財を多く要求したからということにはならない。つまり、労働者がより低い名目賃金を喜んで受け入れることが失業の解決策だとは必ずしも言えないのである。しかしながら、我々がここまで行ってきた賃金と雇用の関係に関する理論の解明はまだ不充分で、その完全な解明は第１９章とその付録においてはじめて行われることになる。
VI
From the time of Say and Ricardo the classical economists have taught
that supply creates its own demand; meaning by this in some
significant, but not clearly defined, sense that the whole of the costs
of production must necessarily be spent in the aggregate, directly or
indirectly, on purchasing the product.
第６節
セイとリカードの時代から古典派経済学者は、供給が自分自身の需要を作り出すと教えてきた。それは、生産の過程でコストとして（＝労働者に）支払った金は全てがことごとくその生産物を直接間接に商品として（＝労働者によって）購入される際に必ず使われるという意味だが、何か意味ありげで曖昧さを残している。
In J. S. Mill's Principles of Political Economy the doctrine is expressly set forth:
What constitutes the means of payment for commodities is simply
commodities. Each person's means of paying for the productions of other
people consist of those which he himself possesses. All sellers are
inevitably, and by the meaning of the word, buyers. Could we suddenly
double the productive powers of the country, we should double the
supply of commodities in every market; but we should, by the same
stroke, double the purchasing power. Everybody would bring a double
demand as well as supply; everybody would be able to buy twice as much,
because every one would have twice as much to offer in exchange.
[Principles of Political Economy, Book III, Chap. xiv. § 2.]
J.S.ミルの『経済学原理』にはこの考え方が明確に述べられている。
商品の支払いのための手段は何かと言えば、それは要するに商品なのである。誰であろうと他人の生産物に対してその人が支払う手段は、自分自身がもっている生産物なのである。全ての売り手は必然的にその言葉の本来の意味において買い手なのである。もし我々が国の生産力を急に２倍にすることが出来たら、全ての市場での商品の供給を２倍にすることが出来る。しかし、それと同時に、我々の購買力も２倍になるのである。誰もが２倍の供給と需要をもたらすのである。誰もが２倍買えるようになるのは、誰もが２倍の商品を提供して交換できるようになるからである。（『経済学原理』第三巻１４章２節）
As a corollary of the same doctrine, it has been supposed that any
individual act of abstaining from consumption necessarily leads to, and
amounts to the same thing as causing the labour and commodities thus
released from supplying consumption to be invested in the production of capital wealth. The following passage from Marshall`s Pure Theory of Domestic Values[9] illustrates the traditional approach:
この考え方の帰結として、消費を控える個人的な行為（＝貯蓄）は、消費に回すことから解放された労働や商品を必然的に投資に回して資本資産の形成に使うことであり、それはつまり投資と同じことだと考えられているのである。マーシャルの『国内価格の純理論』[９]から引いた次の文章は、この伝統的な考え方を説明している。
The whole of a man's income is expended in the purchase of services and
of commodities. It is indeed commonly said that a man spends some
portion of his income and saves another. But it is a familiar economic
axiom that a man purchases labour and commodities with that portion of
his income which he saves just as much as he does with that he is said
to spend. He is said to spend when he seeks to obtain present enjoyment
from the services and commodities which he purchases. He is said to
save when he causes the labour and the commodities which he purchases
to be devoted to the production of wealth from which he expects to
derive the means of enjoyment in the future.
一人の人間の所得はすべてサービスと商品の購入のために消費される。確かに人は所得の一部を支出し残りを貯蓄すると一般に言われている。しかし、人は支出に回した所得だけで労働と商品を購入するのではなく、貯蓄に回した所得でもそうするというのが、有名な経済的原理である。購入したサービスと商品から現在の楽しみを得ようとする場合に「支出する」と言われるのであり、購入した労働と商品を将来の楽しみが予想される富の形成に振り向ける場合に「貯蓄する」と言われるのである。
It is true that it would not be easy to quote comparable
passages from Marshall's later work[10] or from Edgeworth or Professor
Pigou. The doctrine is never stated today in this crude form.
Nevertheless it still underlies the whole classical theory, which would
collapse without it.
確かにこれと似た文章を最近のマーシャルの著書[１０]やエッジワースやピグー教授の本から引用するのは容易ではない。今日ではこの考え方はもはやこれほど生（なま）な形で述べられてはいない。にもかかわらず、この考え方は今でも古典派理論全体の根底をなしており、これがなければ古典派の理論は崩壊してしまうのである。
Contemporary economists, who might hesitate to agree with Mill, do not
hesitate to accept conclusions which require Mill's doctrine as their
premise. The conviction, which runs, for example, through almost all
Professor Pigou's work, that money makes no real difference except
frictionally and that the theory of production and employment can be
worked out (like Mill's) as being based on 'real' exchanges with money
introduced perfunctorily in a later chapter, is the modern version of
the classical tradition.
現代の経済学者は、ミルの考え方に同意することに躊躇しても、ミルの考え方を前提としなければ導き出せない様々な結論を受け入れることには躊躇しない。例えばピグー教授の殆ど全ての著作を通じて見られる信念、つまり貨幣はその流れが停滞する時以外には実質的に大きな役割を果たさず（＝貨幣の中立性、貨幣は仲介物でしかない）、生産と雇用の理論は現物の交換に基づいて構築することが出来るものであり（ミルの理論のように）、貨幣は適当に後の方で紹介しておけばよいとする信念は、古典派の伝統の現代版といえる。
Contemporary thought is still deeply steeped in the notion that if
people do not spend their money in one way they will spend it in
another.[11] Post-war economists seldom, indeed, succeed in maintaining
this standpoint consistently; for their thought today is too much
permeated with the contrary tendency and with facts of experience too
obviously inconsistent with their former view.[12] But they have not
drawn sufficiently far-reaching consequences; and have not revised
their fundamental theory.
現代の考え方も、一つの方面で支出されなかった金は別の方面で支出されるとする考え方に依然としてどっぷりと浸っている[１１]。（確かに第一次大戦後の経済学者がこの立場を一貫して維持することに成功しているとは言えない。というのは、彼らの考えは今日ではこれに反対する動きに強く影響されており、自分たちのかつての物の見方とはあまりにも明らかに対立する経験的事実から影響を受けているからである[１２]。しかしながら、彼らはここから充分に有意義な結論を引き出したわけではないし、自分たちの基本的な理論を作り直したわけでもない。）
In the first instance, these conclusions may have been applied
to the kind of economy in which we actually live, by false analogy from
some kind of non-exchange Robinson Crusoe economy, in which the income
which individuals consume or retain as a result of their productive
activity is, actually and exclusively, the output in specie（同種のもので） of
that activity. But, apart from this, the conclusion that the costs of
output are always covered in the aggregate by the sale-proceeds（売上、収益）
resulting from demand, has great plausibility, because it is difficult
to distinguish it from another, similar-looking proposition which is
indubitable, namely that income derived in the aggregate by all the
elements in the community concerned in a productive activity
necessarily has a value exactly equal to the value of the output.
まず第一に、こうした古典派の様々な結論が、我々が実際に暮らしている経済に適用されてきたのは、ロビンソン・クルーソーの経済のような交換のない経済からの誤った類推によるのかもしれない。そのような経済では、自分の生産活動の結果として個人が消費したり保持したりする所得は、実際のところ、その生産活動による産出物そのものでしかあり得ないからである。しかし、これとは別に、生産にかけた費用は需要に応じた販売の売上によって常にことごとく取り返せるとする結論は、非常にもっともらしいものである。なぜなら、この結論と、これと非常によく似た疑う余地のない法則、つまり、社会の中の生産活動に関わる全ての要素（＝労働者）が生み出す所得の合計は、産出物の価格とちょうど一致するという法則との違いを指摘することは難しいからである。
Similarly it is natural to suppose that the act of an individual, by
which he enriches himself without apparently taking anything from
anyone else, must also enrich the community as a whole; so that (as in
the passage just quoted from Marshall) an act of individual saving
inevitably leads to a parallel act of investment. For, once more, it is
indubitable that the sum of the net increments of the wealth of
individuals must be exactly equal to the aggregate net increment of the
wealth of the community.
同様にして、ある個人が一見して他人から何も奪うことなく自分の富を増やした場合には、その行為は同時に社会全体の富を増やしているに違いないと考えるの
は当然である。つまり（たったいまマーシャルの著書から引用した文章にあるように）、個人が貯蓄を行うことはそのまま投資を行うことに必然的につながっているのである。というのは、繰り返すが、個人の富の純増額が社会の富の純増の合計とちょうど一致するのは疑問の余地がないからである。
Those who think in this way are deceived, nevertheless, by an optical
illusion（錯覚）, which makes two essentially different activities appear
to be the same. They are fallaciously supposing that there is a nexus
which unites decisions to abstain from present consumption with
decisions to provide for future consumption; whereas the motives which
determine the latter are not linked in any simple way with the motives
which determine the former.
それにもかかわらず、このような考え方をする人たちは一種の錯覚におちいっている。彼らは二つの本質的に異なる行動を同じ行動であるとみなしているのだ。彼らは、現在の消費を控える決断と将来の消費に備える決断の間には双方を結びつける関連性があると考えているが、それは間違いである。実際には、後者つまり将来の消費に備える決断をする動機は、前者つまり現在の消費を控える決断をする動機と何の繋がりもないのである。
It is, then, the assumption of equality between the demand price
of output as a whole and its supply price, which is to be regarded as
the classical theory's 'axiom of parallels'. Granted this, all the rest
follows ― the social advantages of private and national thrift, the
traditional attitude towards the rate of interest, the classical theory
of unemployment, the quantity theory of money, the unqualified
advantages of laissez-faire in respect of foreign trade and much else
which we shall have to question.
さらに、産出物全体の需要価格（＝売上）と供給価格（＝費用）が等しい（＝総需要価格は総供給価格と等しい）とする想定こそは、古典派経済学の「平行線の公理」と呼ぶべきものである。そしてこの想定を容認したところから、残りの全ての古典派の経済理論が来ているのだ。曰く、民間と政府が節約することの社会的利益、利子率に対する伝統的態度、雇用の古典的理論、貨幣数量説、海外貿易における自由放任主義の無条件な利益、等々。我々はこれらに異議を唱えていくつもりである。
VII
At different points in this chapter we have made the classical theory to depend in succession on the assumptions:
(1) that the real wage is equal to the marginal disutility of the existing employment;
(2) that there is no such thing as involuntary unemployment in the strict sense;
(3) that supply creates its own demand in the sense that the aggregate
demand price is equal to the aggregate supply price for all levels of
output and employment.
These three assumptions, however, all amount to the same thing in the
sense that they all stand and fall together, any one of them logically
involving the other two.
第７節
我々はこの章の様々な場所において、古典派の理論が次のような想定に依存してることを次々に見てきた。
（１）実質賃金は現行雇用労働力の限界不効用に等しい。
（２）厳密な意味での「非自発的失業」というものは存在しない。
（３）供給は自分自身の需要を作り出す。つまり、生産と雇用がどの水準にあろうと、総需要価格は総供給価格に等しい。
しかしながら、この三つの想定はすべて同じものを指している。つまり、どれ一つをとっても論理的に他の二つのものを含んでおり、全てが成り立つか全てが成り立たないかのどちらかなのである。
Author's Footnotes
[1]. This is in the Ricardian tradition. For Ricardo expressly
repudiated any interest in the amount of the national
dividend（国民分配＝国民所得の量）, as distinct from its distribution（国民所得の配分）. In
this he was assessing correctly the character of his own theory. But
his successors, less clear-sighted, have used the classical theory in
discussions concerning the causes of wealth. Vide Ricardo's letter to
Malthus of October 9, 1820: “Political Economy（経済学） you think is an
enquiry into the nature and causes of wealth ― I think it should be
called an enquiry into the laws which determine the division of the
produce of industry amongst the classes who concur in its formation. No
law can be laid down respecting quantity, but a tolerably correct one
can be laid down respecting proportions. Every day I am more satisfied
that the former enquiry is vain and delusive, and the latter only the
true objects of the science.”
[2]. For example, Prof. Pigou in the Economics of Welfare (4th ed. p.
127) writes (my italics): “Throughout this discussion, except when the
contrary is expressly stated, the fact that some resources are
generally unemployed against the will of the owners is ignored. This
does not affect the substance of the argument, while it simplifies its
exposition.”. Thus, whilst Ricardo expressly disclaimed any attempt to
deal with the amount of the national dividend as a whole, Prof. Pigou,
in a book which is specifically directed to the problem of the national
dividend, maintains that the same theory holds when there is some
involuntary unemployment as in the case of full employment.
[3]. Prof. Pigou's Theory of Unemployment is examined in more detail in the Appendix to Chapter 19 below.
[4]. Cf. the quotation from Prof. Pigou above, p. 5, footnote.
[5]. This point is dealt with in detail in the Appendix to Chapter 19 below.
[6]. This argument would, indeed, contain, to my thinking, a large
element of truth, though the complete results of a change in
money-wages are more complex, as we shall show in Chapter 19 below.
[7]. Cf. Chapter 19, Appendix.
[8]. The argument runs as follows: n men are employed, the nth man adds
a bushel a day to the harvest, and wages have a buying power of a
bushel a day. The n + 1 th man, however, would only add .9 bushel a
day, and employment cannot, therefore, rise to n + 1 men unless the
price of corn rises relatively to wages until daily wages（日給） have a
buying power of .9 bushel. Aggregate wages would then amount to 9/10 (n
+ 1) bushels as compared with n bushels previously. Thus the employment
of an additional man will, if it occurs, necessarily involve a transfer
of income from those previously in work to the entrepreneurs.
[9]. p. 34.
[10]. Mr. J. A. Hobson, after quoting in his Physiology of Industry (p.
102) the above passage from Mill, points out that Marshall commented as
follows on this passage as early as his Economics of Industry, p. 154.
“But though men have the power to purchase, they may not choose to use
it.” “But”, Mr Hobson continues, “he fails to grasp the critical
importance of this fact, and appears to limit its action to periods of
'crisis'.” This has remained fair comment, I think, in the light of
Marshall's later work.
[11]. Cf. Alfred and Mary Marshall, Economics of Industry, p. 17: “It
is not good for trade to have dresses made of material which wears out
quickly. For if people did not spend their means on buying new dresses
they would spend them on giving employment to labour in some other
way.” The reader will notice that I am again quoting from the earlier
Marshall. The Marshall of the Principles had become sufficiently
doubtful to be very cautious and evasive. But the old ideas were never
repudiated or rooted out of the basic assumptions of his thought.
[12].. It is this distinction of Prof. Robbins that he, almost alone,
continues to maintain a consistent scheme of thought, his practical
recommendations belonging to the same system as his theory.
著者注
[１] これはリカード派の伝統である。リカードは国民分配分（＝国民所得）の分配はともかく、国民分配分の量に対する関心はないと言っている。この点で彼は自分の理論の性格を正しく理解している。しかし、彼ほど賢明ではない彼の後継者たちは古典派の理論を富の源泉についての議論に利用してきた。リカードがマルサスに宛てた1820年10月9日の手紙を参照せよ。「あなたは経済学を富の性格と源泉についての研究だと考えている。私は経済学を、産業生産物をその製造に関わる階級の間でどのように分配するかを決める法則についての研究だと見るべきだと思っている。量に関してはどんな法則も決めることもできないが、割合に関する法則ならかなり正確なものを定めることが出来る。私は前者の研究は無意味な出鱈目なものであり、後者だけが科学の真の対象であるとする確信を日々深めている」
[２] 例えば、ピグー教授はその著「厚生経済学」（第４版127頁）の中で「一部の人的資源が全体的に不本意ながら雇用されないでいるという事実は、特に言及しない限り、この議論の間じゅう無視されている。これによって話が単純化される一方で、これによって議論の本質が影響を受けることはないからである」と言っている。リカードが全体としての国民分配分（＝国民所得）の量を扱うことに明確に反対したのに対して、ピグー教授は国民分配分の問題を専門的に扱った著書の中で、このように「非自発的失業」がある場合も「完全雇用」の状態と同じ理論が有効だと主張しているのである。
[３] ピグー教授の『失業理論』については１９章の付録でさらに詳細な検討を加えた。
[４] 上記注のピグー教授からの引用参照。
[５] この点は第１９章の付録で詳しく論じている。
[６] 私の考えでは、この議論は多くの事実を含んでいる。ただし第１９章で見るとおり、名目賃金の変化がもたらす全ての結果はもっと複雑である。
[７] 第１９章の付録を参照。
[８] これは具体的には次のようになる。いま農作業にＮ人の人が雇われていて、Ｎ番目に雇われた人は１日１ブッシェルを収穫しており、１日１ブッシェル買える賃金（＝実質賃金）をもらっているとする。しかしながら、そこへＮ+1番目の人が雇われても収穫は１日0.9ブッシェルしか増えないはずである（＝限界生産力逓減の法則）。したがって、小麦の価格が上昇して１日の日当で0.9ブッシェルしか買えなくなるときに（＝実質賃金が0.9ブッシェルに下がったとき限界生産力と実質賃金が一致）はじめて雇用労働力はＮ+1人に増えることができる（＝失業率の低下は物価の上昇を伴う）。そのときの総賃金（＝実質賃金）は以前のＮブッシェルから0.9×(Ｎ+1)ブッシェルになる。こうして、追加の１人の雇用は、元から働いている人達から企業家への所得の移転が必ず伴うのである（＝元からいる人の実質賃金は下がる）。
[９] ３４ページ
[１０] J.A.ホブソンは『産業の生理学』（１０２頁）に上記のミルの文章を引用してから、マーシャルが自らの『産業の経済学』の１５４頁で早くからこのミルの文章について次のようにコメントしているのを紹介している。「人びとは購買力をもっていてもそれを使うとは限らない」。それに対してホブソンは「しかしマーシャルはこの事実（＝金を使わないことがある事）の決定的な重要性を把握せず、購買力を使わない行為を「危機」の期間に限定しているようだ」と書いた。この意見はマーシャルの後の作品を見ても正しいと思う。
[１１] アルフレッド＆メアリー・マーシャルの『産業の経済学』１７頁参照。「すぐに擦り切れる服地で洋服を作るのはうまい商売の仕方ではない。たとえ（＝丈夫な服地のせいで）人びとが新しい洋服を買うためにお金を使わなくなっても、別の方法でお金を使って労働者の仕事をつくるからである」。読者は、私がまたもや初期のマーシャルから引用していることにお気づきだろう。のちの『経済原理』を書いた頃のマーシャルは充分懐疑的になっておりもっと慎重で曖昧な書き方をしている。しかし、彼は自分の思想の基盤となって様々な想定の中から、昔のこの考え方を決して捨て去りはしなかったのである。
[１２] ロビンズ教授は殆どただ一人、一貫して思考の骨格を維持し続けており、彼の実践的提言は自身の理論と同じ方法論から来ているが、これは彼のこの非凡さゆえである。
Chapter 3. The Principle of Effective Demand
第３章 有効需要の原理
I
WE need, to start with, a few terms which will be defined
precisely later. In a given state of technique, resources and costs,
the employment of a given volume of labour by an entrepreneur involves
him in two kinds of expense: first of all, the amounts which he pays
out to the factors of production (exclusive of other entrepreneurs) for
their current services, which we shall call the factor cost（要素費用） of
the employment in question; and secondly, the amounts which he pays out
to other entrepreneurs for what he has to purchase from them together
with the sacrifice（犠牲、出費、支出、contributeの裏返しの言葉、使用） which he incurs by
employing the equipment instead of leaving it idle, which we shall call
the user cost（＝使用費用） of the employment in question.[1]
第１節
我々はまず若干の専門用語から始めなければならない（用語の正確な定義は後に行う）。一定の技術と資源と経費のもとで企業家が一定量の労働者を雇用するた
めには２種類の経費が必要である。その第一は、生産要素（ほかの企業家を除く）がもたらす当期のサービスに対して支払う金額で、これを当該雇用にかかる「要素費用」（＝賃金）と呼ぶことにする。その第二は、ほかの企業家から購入するものについてその企業家に支払う金額（＝原材料費）で、設備を止めずに稼働させ続けるために必要な出費（＝可変的減価償却費）をそれに加えて、当該雇用にかかる「使用費用（＝原材料費＋可変的減価償却費）」（＝userのerは「反復」を表すから「使用者費用」は誤訳と伊東光晴の『現代経済学事典』、設備を動かすのに必要な費用、可変費用）と呼ぶことにする[１]。
The excess of（A over B で AがBを上回る分、つまりAからBを引いた余り） the value of the
resulting output over the sum of its factor cost and its user cost is
the profit or, as we shall call it, the income of the entrepreneur. The
factor cost is, of course, the same thing, looked at from the point of
view of the entrepreneur, as what the factors of production regard as
their income.
その経費の結果である産出物の価格（＝後のＡ）が要素費用（＝後のＦ）と使用費用（＝後のＵ）の合計（＝主要費用）を上回る額が「企業家の利潤」（＝Ａ－Ｕ－Ｆ）であるが、それを我々は「企業家の所得」と呼ぶこともある。要素費用とは企業家の目から見たもので、もちろん生産要素（＝労働者）が自分たちの所得とみなしているものと同じである。
Thus the factor cost and the entrepreneur's profit make up, between
them, what we shall define as the total income resulting from the
employment given by the entrepreneur. The entrepreneur's profit thus
defined is, as it should be, the quantity which he endeavours to
maximise when he is deciding what amount of employment（＝労働量） to offer.
It is sometimes convenient, when we are looking at it from the
entrepreneur's standpoint, to call the aggregate income (i.e. factor
cost plus profit) resulting from a given amount of employment the
proceeds of that employment. On the other hand, the aggregate supply
price [2] of the output of a given amount of employment is the
expectation（予想、見込み） of proceeds which will just make it worth the while
of the entrepreneurs to give that employment.[3]
そして、「要素費用」と「企業家の利潤」の二つを合わせたものを「総所得」と呼ぶことにする。総所得は企業家が雇用を提供した結果生まれるものである。当然ながら、企業家はどれだけの雇用を提供するか決めるときに、上で定義した「企業家の利潤」が最大になるように努力する。だから、時には、企業家の観点から見て、一定の雇用量から生まれる「総所得（即ち要素費用＋企業家の利潤）」をその「雇用の売上」と呼ぶのが便利である。逆に言えば、ある雇用量が生み出す産出物の総供給価格（＝後のＺ、総費用）[２]とは、企業家が将来もその雇用量を提供する費用をまかなう売上の予想値である[３]。
It follows that in a given situation of technique, resources and
factor cost per unit of employment, the amount of employment, both in
each individual firm and industry and in the aggregate, depends on the
amount of the proceeds which the entrepreneurs expect to receive from
the corresponding output.[4] For entrepreneurs will endeavour to
fix（決める） the amount of employment at the level which they expect to
maximise the excess of the proceeds over the factor cost.
つまり、技術と資源と雇用１単位あたりの要素費用が一定の場合には、個別の企業や産業においても全体の企業や産業においても、雇用量は、それに対応する産出物の売上に対する予想値に基づいて決まるのである[４]。というのは、企業家は売上が要素費用を上回る額が最大になると予想するレベルに雇用量を合わせようと努めるからである。
Let Z be the aggregate supply price of the output from employing N men,
the relationship between Z and N being written Z = φ(N), which can be
called the Aggregate Supply Function.[5] Similarly, let D be the
proceeds which entrepreneurs expect to receive from the employment of N
men, the relationship between D and N being written D = f(N), which can
be called the Aggregate Demand Function.
Ｎ人の雇用から生まれる産出物の総供給価格（＝総費用）をＺとし、ＺとＮの関係を Ｚ =φ(Ｎ)と書くと、これは「総供給関数」（＝費用の関数）と呼ぶことが出来る[５]。同様にして、Ｎ人の雇用から生まれる売上の予想値をＤとし、ＤとＮの関係をＤ = f(Ｎ)と書くと、これは「総需要関数」（＝売上の関数）と呼ぶことが出来る。
Now if for a given value of N the expected proceeds are greater than
the aggregate supply price, i.e. if D is greater than Z, there will be
an incentive（インセンティブ、誘引） to entrepreneurs to increase employment beyond
N and, if necessary, to raise costs by competing with one another for
the factors of production, up to the value of N for which Z has become
equal to D.
そこで、もしある数Ｎに対する売上の予想値（＝Ｄ）が総供給価格（＝Ｚ）より大きい場合、即ちＤがＺより大きい場合には、雇用をＮより大きくしたいというインセンティブが企業家たちに生まれる。そして必要があれば、企業家たちは互いに競いあってＺがＤと等しくなるようなＮの値になるまで、生産要素を獲得するために費用を増やそうとする気持ちになるのである。
Thus the volume of employment is given by the point of intersection
between the aggregate demand function and the aggregate supply
function; for it is at this point that the entrepreneurs' expectation
of profits will be maximised. The value of D at the point of the
aggregate demand function, where it is intersected by the aggregate
supply function, will be called the effective demand（有効需要）. Since this
is the substance of the General Theory of Employment, which it will be
our object to expound, the succeeding chapters will be largely occupied
with examining the various factors upon which these two functions
depend.
このようにして雇用量は、総需要関数と総供給関数が交わる点によって与えられる。というのは、企業家の利潤の予想値が最大になるのは、この点においてだからである。総需要関数が総供給関数と交わる点におけるＤの値を「有効需要」（＝実際の売上）と呼ぶことにする。これが「雇用の一般的理論」の本質であり、これを詳しく説明することが我々の目標なので、以降の章ではこの二つの関数が依存する様々な要素について詳しく検討していくことになる。
The classical doctrine, on the other hand, which used to be expressed
categorically in the statement that “Supply creates its own Demand” and
continues to underlie all orthodox economic theory, involves a special
assumption as to the relationship between these two functions. For
“Supply creates its own Demand” must mean that f(N) and φ(N) are equal
for all values of N, i.e. for all levels of output and employment; and
that when there is an increase in Z( = φ(N)) corresponding to an
increase in N, D( =f(N)) necessarily increases by the same amount as Z.
それに対して、「供給はそれ自身の需要を作り出す」と明確な形で言われ、正統派経済学の根底となり続けている古典派の教義は、上記の総需要と総供給の二つ
の関数の間に特別な関係があることを前提とするものである。というのは、「供給はそれ自身の需要を作り出す」ということは、Ｎの全ての値に対して、即ち産
出量と雇用量のあらゆるレベルに対て、f(Ｎ)とφ(Ｎ)が一致するということであり、さらに、Ｎの増加に対応するＺ( =φ(Ｎ))の増加があるとき、Ｄ( ＝ f(Ｎ))は必ずＺと同じ量だけ増加することを意味する。
The classical theory assumes, in other words, that the aggregate demand
price (or proceeds) always accommodates itself to the aggregate supply
price; so that, whatever the value of N may be, the proceeds D assume a
value equal to the aggregate supply price Z which corresponds to N.
That is to say, effective demand, instead of having a unique（一意的な）
equilibrium value, is an infinite range of values all equally
admissible; and the amount of employment is indeterminate except in so
far as the marginal disutility of labour sets an upper limit.
言い換えれば、古典派の理論は、総需要価格（つまり売上）は常に総供給価格に連動して変化して、Ｎの値が何であるかに関わらず、売上ＤはＮに対応する総供給価格Ｚと同じ値をとると想定しているのだ。つまり、有効需要は一つの均衡値ではなく、可能な限りあらゆる範囲の値となるのである。そして雇用量を決めるものは「労働力の限界不効用」（＝労働供給の公理）が決める雇用の上限だけとなる（＝雇われたい人は全員雇われる）。
If this were true, competition between entrepreneurs would
always lead to an expansion of employment up to the point at which the
supply of output as a whole ceases to be elastic, i.e. where a further
increase in the value of the effective demand will no longer be
accompanied by any increase in output. Evidently this amounts to the
same thing as full employment. In the previous chapter we have given a
definition of full employment in terms of the behaviour of labour. An
alternative, though equivalent, criterion is that at which we have now
arrived, namely a situation, in which aggregate employment is inelastic
in response to an increase in the effective demand for its output. Thus
Say's law, that the aggregate demand price of output as a whole is
equal to its aggregate supply price for all volumes of output, is
equivalent to the proposition that there is no obstacle to full
employment. If, however, this is not the true law relating the
aggregate demand and supply functions, there is a vitally important
chapter of economic theory which remains to be written and without
which all discussions concerning the volume of aggregate employment are
futile.
もしこれが事実なら、雇用は起業家たちの間の競争によって常に拡張していき、産出物の供給が全体的に弾力性を失うところに、即ち、もはや有効需要の値（＝実際の売上）の増加に産出量の増加が連動しなくなるところに到達することになる。これが「完全雇用」と同じことを意味するのは明らかである。前の章で我々は労働者の行動から見た「完全雇用」の定義（＝第二公理を満たす状況、非自発的失業がない状況）を示した（■）。そして今や我々は同じ内容だがそれとは別のもう一つの完全雇用の基準に到達したのである。それは、雇用が生み出す産出量に応じて有効需要（＝実際の売上）も増加していって、もはや総雇用が弾力性を失って有効需要の増加に応じることが出来なくなった状況である。そうすると、産出物全体の総需要価格は全産出量に対する総供給価格に等しいというセイの法則は、完全雇用に至る障害物は存在しない（＝弾力性がなくなることはない）と言っているに等しい。しかし、もしセイの法則が総需要関数と総供給関数を関する真の法則でないのなら、まだ書かれていない経済理論の非常に重要な部分、それなしには総雇用量についてのあらゆる議論が無意味になってしまう部分が存在することになる。
II
A brief summary of the theory of employment to be worked out in
the course of the following chapters may, perhaps, help the reader at
this stage, even though it may not be fully intelligible. The terms
involved will be more carefully defined in due course. In this summary
we shall assume that the money-wage and other factor costs are constant
per unit of labour employed. But this simplification, with which we
shall dispense later, is introduced solely to facilitate the
exposition. The essential character of the argument is precisely the
same whether or not money-wages, etc., are liable to change.
第２節
以下の章で詳しく論ずることになる雇用理論をここで簡単にまとめておくのは、たとえあまり分かりよくはなくても、読者の役に立つだろう。ここに含まれる専門用語の詳しい定義は順を追って行う。この要約では、雇用労働１単位あたりの名目賃金やその他の要素費用は一定とする。しかし、のちに不要になるこの単純化は説明を容易にするためであって、名目賃金やその他の要素費用が変化しても議論の本質が変わることはない。
The outline of our theory can be expressed as follows. When employment
increases,aggregate real income is increased. The psychology of the
community is such that when aggregate real income is increased
aggregate consumption is increased, but not by so much as income. Hence
employers would make a loss if the whole of the increased employment
were to be devoted to satisfying the increased demand for immediate
consumption. Thus, to justify any given amount of employment there must
be an amount of current investment sufficient to absorb the excess of
total output over what the community chooses to consume when employment
is at the given level.
我々の雇用理論の概略は次のように表すことができる。雇用が増加すると実質総所得が増加する。実質総所得が増加すると総消費が増加するが、総消費の増加は総所得の増加分より少ないのが、社会の心理である。だから、増加している当面の消費需要を満たすために増加している雇用の全てを振り向けてしまうと、使用者にロスが出ることになる。つまり、雇用量を正当化する（＝企業家に損が出ない）ために、当期の投資量（＝消費に回らなかった貯蓄）が充分存在して、全産出量が雇用レベルに対応する社会の消費量を上回る分（＝生産超過分）を吸収できければならない。
For unless there is this amount of investment, the receipts of the
entrepreneurs will be less than is required to induce them to offer the
given amount of employment. It follows, therefore, that, given what we
shall call the community's propensity to consume, the equilibrium level
of employment, i.e. the level at which there is no inducement to
employers（使用者） as a whole either to expand or to contract employment,
will depend on the amount of current investment. The amount of current
investment will depend, in turn, on what we shall call the inducement
to invest; and the inducement to invest will be found to depend on the
relation between the schedule of the marginal efficiency of capital and
the complex of rates of interest on loans of various maturities and
risks.
というのは、もしこの投資量がなけれれば、企業家の収入が、この雇用量を提供する気になるために必要なレベルを下回ってしまうからである。すると、我々が社会の消費性向と呼ぶものが一定とすると、雇用の均衡レベル、即ち、全ての使用者がもはや雇用を拡大も縮小もしたくなくなるレベルは、当期の投資量によって決まることになる。そして、その当期の投資量は我々が「投資のインセンティブ」と呼ぶものによって決まることになり、さらに、この投資のインセンティブは、様々なリスクと満期をもつローンの利子率複合体（＝１３章２節。期間によって異なる利子率を総称したもの）と「資本の限界効率表」（＝１１章）との関係によって決まることが見出されるだろう。
Thus, given the propensity to consume and the rate of new investment,
there will be only one level of employment consistent with equilibrium;
since any other level will lead to inequality between the aggregate
supply price of output as a whole and its aggregate demand price. This
level cannot be greater than full employment, i.e. the real wage cannot
be less than the marginal disutility of labour.
つまり、消費性向と新たな投資水準が決まると、均衡状態と矛盾しない雇用レベルは一つだけになる。他の雇用レベルでは産出物全体の総供給価格とその総需要価格が一致しなくなるからである。この雇用レベルは完全雇用を上回ることはありえない。つまり、実質賃金が「労働力の限界不効用」を下回る可能性はないのである。
But there is no reason in general for expecting it to be equal to
full employment.The effective demand associated with full employment is
a special case, only realised when the propensity to consume and the
inducement to invest stand in a particular relationship to one another.
This particular relationship, which corresponds to the assumptions of
the classical theory, is in a sense an optimum relationship. But it can
only exist when, by accident or design, current investment provides an
amount of demand just equal to the excess of the aggregate supply price
of the output resulting from full employment over what the community
will choose to spend on consumption when it is fully employed.
しかしながら、概してこの雇用レベルが完全雇用と等しいと予想する理由はない。有効需要が完全雇用を伴うのは、消費性向と投資インセンティブが互いに特殊な関係にあるときだけ実現される特別なケースだからである。この特殊な関係は古典派理論の様々な想定に対応しており、ある意味では最適な関係と言えるものである。しかしながら、この最適な関係が生まれるのは限られている。それは、故意か偶然でも、完全雇用から生まれる産出物の総供給価格が完全雇用のときの社会の消費量を上回る分に丁度等しいだけの需要量を、当期の投資が提供できるときだけである。
This theory can be summed up in the following propositions:
(1) In a given situation of technique, resources and costs, income
(both money-income and real income) depends on the volume of employment
N.
(2) The relationship between the community's income and what it can be
expected to spend on consumption, designated by D1, will depend on the
psychological characteristic of the community, which we shall call its
propensity to consume. That is to say, consumption will depend on the
level of aggregate income and, therefore, on the level of employment N,
except when there is some change in the propensity to consume.
(3) The amount of labour N which the entrepreneurs decide to employ
depends on the sum (D) of two quantities, namely D1, the amount which
the community is expected to spend on consumption, and D2, the amount
which it is expected to devote to new investment. D is what we have
called above the effective demand.
この雇用理論は以下の命題にまとめられる。
（１）技術と資源と経費を一定とした場合、所得（名目所得と実質所得）は雇用量Ｎによって決まる。
（２）社会の所得と社会が消費に支出することを予想される量ーこれをＤ１とするーとの関係は社会の心理的傾向によって決まる。この心理的傾向を我々はその
社会の「消費性向」と呼ぶことにする。つまり、消費性向に変化がない限り、消費は総所得の水準によって、したがって、雇用レベルＮによって決まる。
（３）企業家が雇用することを決める労働者の量Ｎは、次の二つの量の合計（Ｄ）によって決まる。即ち、Ｄは社会が消費に支出することを予想される量Ｄ１（＝消費）と社会が新たな投資に振り向けると予想される量Ｄ２（＝投資）の合計である。Ｄは我々が上記において「有効需要」と呼んだものとなる。
(4) Since D1 + D2 = D = φ(N), where φ is the aggregate supply function,
and since, as we have seen in (2) above, D1 is a function of N, which
we may write χ(N), depending on the propensity to consume, it follows
that φ(N) - χ(N) = D2.
（４）φは総供給関数（＝Ｚ）で（＝均衡状態なので）Ｄ１ + Ｄ２ = Ｄ = φ(Ｎ)であり、上記（２）で見たようにＤ１はＮの関数でχ(Ｎ)と書くと、これは消費性向に依存する関数である。そうすと、（Ｄ－Ｄ１＝Ｄ２だから）φ(Ｎ) - χ(Ｎ) = Ｄ２となる。
(5) Hence the volume of employment in equilibrium depends on (i) the
aggregate supply function, φ, (ii) the propensity to consume, χ, and
(iii) the volume of investment, D2. This is the essence of the General
Theory of Employment.
（５）すると均衡状態にある雇用量（＝Ｎ）は、(ｉ)総供給関数φと(ｉｉ)消費性向χと(ｉｉｉ)投資量Ｄ２によって決まることになる。これが「雇用の一般理論」のかなめである。
(6) For every value of N there is a corresponding marginal productivity
of labour in the wage-goods industries; and it is this which determines
the real wage. (5) is, therefore, subject to the condition that N
cannot exceed the value which reduces the real wage to equality with
the marginal disutility of labour. This means that not all changes in D
are compatible with our temporary assumption that money-wages are
constant. Thus it will be essential to a full statement of our theory
to dispense with this assumption.
（６）賃金財産業の労働の限界生産力はどのＮの値（＝雇用量）にも対応して存在する。そしてこの限界生産力が実質賃金を決定する（＝労働需要の公理）。し
たがって、（５）の命題は、Ｎの値は、実質賃金が労働力の限界不効用と等しくなる（＝完全雇用、労働供給）値を上回れないという条件が付く。このことは、
Ｄ（＝有効需要）のあらゆる変化と名目賃金（＝Ｎによって決まる）を一定とする上記の仮定（→第３章第２節第１段落）が必ずしも両立するわけではないことを意味する。この仮定を撤去することは我々の雇用理論の本格的な記述には欠かせないのである。
(7) On the classical theory, according to which D = φ(N) for all values
of N, the volume of employment is in neutral equilibrium for all values
of N less than its maximum value; so that the forces of competition
between entrepreneurs may be expected to push it to this maximum value.
Only at this point, on the classical theory, can there be stable
equilibrium.
（７）Ｎのあらゆる値に対して Ｄ＝φ(Ｎ) が成り立つ古典派の理論（＝需要と供給が一致する）では、Ｎの最大値（＝完全雇用）を除くあらゆるＮの値において、雇用量は不安定な均衡状態にある。その結果、企業家たちの競争によって雇用がこの最大値にまで押し上げられることが予想されるのである。古典派の理論では、この最大点においてだけ安定した均衡が可能となる。
(8) When employment increases, D1 will increase, but not by so much as
D; since when our income increases our consumption increases also, but
not by so much. The key to our practical problem is to be found in this
psychological law. For it follows from this that the greater the volume
of employment the greater will be the gap between the aggregate supply
price (Z) of the corresponding output and the sum (D1) which the
entrepreneurs can expect to get back out of the expenditure of
consumers.
（８）雇用が増加すると、Ｄ１（＝消費）も増加するが、それはＤ（＝所得）の増加分よりは少ない。所得が増加すると消費も増加するが、それは所得の増加分より少ないからである。我々が抱えている現実の問題に対する鍵はこの心理法則の中に見出すことが出来る。というのは、この心理法則のせいで、雇用量が増えれば増えるほど、それに見合った産出物の総供給価格（Ｚ）と、企業家が消費者の支出から回収することを予想できる額（Ｄ１）とのギャップが大きくなるからである。
Hence, if there is no change in the propensity to consume, employment
cannot increase, unless at the same time D2 is increasing so as to fill
the increasing gap between Z and D1. Thus ― except on the special
assumptions of the classical theory according to which there is some
force in operation which, when employment increases, always causes D2
to increase sufficiently to fill the widening gap between Z and D1 ―
the economic system may find itself in stable equilibrium with N at a
level below full employment, namely at the level given by the
intersection of the aggregate demand function with the aggregate supply
function.
したがって、もし「消費性向」に変化がないなら、Ｚ（＝総供給価格）とＤ１（＝消費）の間の拡大するギャップを埋めるために、Ｄ２（＝投資）が増加しない限り、雇用が増えることは不可能である。つまり、総需要関数と総供給関数が交差するレベルにあるＮ（＝雇用）が完全雇用より低いレベルのままで、経済が安定した均衡状態に入ってしまう可能性があることになる。古典派の理論の特殊な想定のように、雇用が増加すると、Ｄ２を常に増加させる何らかの力が働いて、
ＺとＤ１の間の拡大するギャップを埋めてくれるなら話は別であるが。
Thus the volume of employment is not determined by the marginal
disutility of labour measured in terms of real wages, except in so far
as the supply of labour available at a given real wage sets a maximum
level to employment. The propensity to consume and the rate of new
investment determine between them the volume of employment, and the
volume of employment is uniquely related to a given level of real wages
― not the other way round. If the propensity to consume and the rate of
new investment result in a deficient effective demand, the actual level
of employment will fall short of the supply of labour potentially
available at the existing real wage, and the equilibrium real wage will
be greater than the marginal disutility of the equilibrium level of
employment.
つまり、雇用量を決めるのは実質賃金で測った「労働力の限界不効用」ではないのである。ある実質賃金のもとで利用可能な労働の供給量は雇用の最大値を定め
るだけなのである。雇用量を決めるのは消費性向（＝Ｄ１）と新たな投資水準（＝Ｄ２）の二つなのである。そして、その雇用量はあるレベルの実質賃金と一意的なつながりをもってはいても、その逆に実質賃金が雇用量を決めるこはないのである。もし消費性向と新たな投資水準が有効需要の不足をもたらしたなら、実
際の雇用レベルは現行実質賃金で潜在的に利用可能な労働の供給量を下回ることになるのだ。そして、その時に均衡した実質賃金は雇用の均衡レベルである限界不効用（＝完全雇用）より高くなるのである（＝実質賃金の高止まり）。
This analysis supplies us with an explanation of the paradox of poverty
in the midst of plenty. For the mere existence of an insufficiency of
effective demand may, and often will, bring the increase of employment
to a standstill before a level of full employment has been reached. The
insufficiency of effective demand will inhibit the process of
production in spite of the fact that the marginal product of labour
still exceeds in value the marginal disutility of employment.
この分析によって我々は豊かさのただ中における貧困というパラドックスの説明を手に入れる。というのは、有効需要が不足しているだけで、雇用の増加は完全雇用のレベルに達する前に止まってしまうかもしれず、またしばしば実際に止まってしまうからである。労働力の限界生産物（＝労働需要の公理、企業側の提示する賃金）が雇用労働力の限界不効用（＝労働供給の公理、労働側が要求する賃金）を価格において上回っているにも関わらず、有効需要の不足は生産の過程をストップさせてしまうのである。
Moreover the richer the community, the wider will tend to be the gap
between its actual and its potential production; and therefore the more
obvious and outrageous the defects of the economic system. For a poor
community will be prone to consume by far the greater part of its
output, so that a very modest measure of investment will be sufficient
to provide full employment; whereas a wealthy community will have to
discover much ampler opportunities for investment if the saving
propensities of its wealthier members are to be compatible with the
employment of its poorer members.
そのうえ、社会が豊かになればなるほど、実際の生産量と潜在的な生産量の間のギャップはますます広がっていき、それに従って、経済システム（＝現代資本主義）の欠陥は次第にあらわとなり、暴力的になってくるのである。というのは、貧しい社会では産出物のかなり大きな部分が消費されてしまう傾向があるので、ごく控えめな投資でも充分に完全雇用をもたらすのに対して、豊かな社会では、もし富裕層の貯蓄性向と貧困層の雇用を両立させるつもりなら、かなり豊富な投資機会が見出されねばならないからである。
If in a potentially wealthy community the inducement to invest
is weak, then, in spite of its potential wealth, the working of the
principle of effective demand will compel it to reduce its actual
output, until, in spite of its potential wealth, it has become so poor
that its surplus over its consumption is sufficiently diminished to
correspond to the weakness of the inducement to invest.
もし潜在的に豊かな社会で投資のインセンティブが弱ければ、その潜在的な豊かさに関わらず、有効需要の原理の働きで実際の産出量は引き下げられ、最後には、その潜在的な豊かさにも関わらず、社会は貧困化していき（＝豊かさの中の貧困）、消費を上回る余分の生産は投資のインセンティブの弱さに合った量まで減少することになる。
But worse still. Not only is the marginal propensity to consume[6]
weaker in a wealthy community, but, owing to its accumulation of
capital being already larger, the opportunities for further investment
are less attractive unless the rate of interest falls at a sufficiently
rapid rate; which brings us to the theory of the rate of interest and
to the reasons why it does not automatically fall to the appropriate
level, which will occupy Book IV.
しかし、もっと悪いことがある。豊かな社会では限界消費性向[６]が弱いだけでなく、資本の蓄積が既に大きいために、利子率が充分な早さで下がらないと、さらに投資する機会は魅力を失ってしまうのである。こうして、我々は利子率の理論へ向かい、適切なレベルまで利子率が自動的に下がらない理由を考えることになる。それは第４巻のことである。
Thus the analysis of the Propensity to Consume, the definition of the
Marginal Efficiency of Capital and the theory of the Rate of Interest
are the three main gaps in our existing knowledge which it will be
necessary to fill. When this has been accomplished, we shall find that
the Theory of Prices falls into its proper place as a matter which is
subsidiary to our general theory. We shall discover, however, that
Money plays an essential part in our theory of the Rate of Interest;
and we shall attempt to disentangle the peculiar characteristics of
Money which distinguish it from other things.
つまり、「消費性向」の分析と「資本の限界効率」の定義と「利子率」の理論こそは、現代の我々の知識からぽっかり抜け落ちている要素であり、この空隙を是非とも埋める必要があるのである。それが達成されたとき、「物価の理論」がこの一般理論の副次的な問題として相応しい居場所を見つけることになる。一方、我々の「利子率」の理論のなかでは「貨幣」は極めて重要な役割をしめていることが見出されるはずである。また「貨幣」が他のものと異なる特性をもっていることが明らかにされるだろう。
III
The idea that we can safely neglect the aggregate demand function is
fundamental to the Ricardian economics, which underlie what we have
been taught for more than a century. Malthus, indeed, had vehemently
opposed Ricardo's doctrine that it was impossible for effective demand
to be deficient; but vainly. For, since Malthus was unable to explain
clearly (apart from an appeal to the facts of common observation) how
and why effective demand could be deficient or excessive, he failed to
furnish an alternative construction;
第３節
総需要関数は無視しても構わないとする思想は、１００年以上の間我々が教えられてきた経済学の基本となっているリカード経済学の根本思想である。確かに、有効需要（＝消費予想＋投資予想）が不足するなどありえないとするリカードの教義にマルサスは激しく反対したがうまくいかなった。というのは、マルサスはどうして有効需要が不足したり過剰になったりするのかうまく説明でず、単に常識的な観察的事実に訴えるしかなかったので、リカードに取って代わる体系を提示することができなかったからである。
and Ricardo conquered England as completely as the Holy Inquisition
conquered Spain. Not only was his theory accepted by the city, by
statesmen and by the academic world. But controversy ceased; the other
point of view completely disappeared; it ceased to be discussed. The
great puzzle of Effective Demand with which Malthus had wrestled
vanished from economic literature. You will not find it mentioned even
once in the whole works of Marshall, Edgeworth and Professor Pigou,
from whose hands the classical theory has received its most mature
embodiment. It could only live on furtively, below the surface, in the
underworlds of Karl Marx, Silvio Gesell or Major Douglas.
そして、宗教裁判がスペインを征服したようにしてリカードは英国を完全に征服してしまった。彼の理論はロンドンの金融街にも政界にも学界にも受け入れられただけでなく、論争自体が終わってしまったのである。別の見方は完全に姿を消してしまい、もはや議論の対象にならなくなってしまった。そして、マルサスが取り組んだ「有効需要」という巨大な謎は経済書の中から姿を消してしまったのである。古典派の理論を成熟した形で完成させたマーシャルとエッジワースとピグー教授の本には有効需要という言葉はどこにも見当たらない。カール・マルクスとシルヴィオ・ゲゼルとダグラス少佐のいた裏世界で、ひっそりと命を長らえていただけなのである。
The completeness of the Ricardian victory is something of a curiosity
and a mystery. It must have been due to a complex of suitabilities in
the doctrine to the environment into which it was projected. That it
reached conclusions quite different from what the ordinary uninstructed
person would expect, added, I suppose, to its intellectual prestige.
That its teaching, translated into practice, was austere and often
unpalatable, lent it virtue. That it was adapted to carry a vast and
consistent logical superstructure, gave it beauty.
リカードの勝利の完璧さは不思議なほどで興味をそそられる。リカードの教義にはそれが提示された環境に対する様々な適応力があったに違いない。彼の教義は一般の無教養の人たちにとっては予想外の結論に至るものだったが、それによって知的権威が付加された。また、実行に移された彼の教えは禁欲的でしばしば口に苦いものであったが、それによって美徳が付け加わった。さらに、彼の教義は広範かつ一貫性のある論理的上部構造をもつように作られていたので、美しさも備わっていた。
That it could explain much social injustice and apparent cruelty as an
inevitable incident in the scheme of progress, and the attempt to
change such things as likely on the whole to do more harm than good,
commended(推薦する) it to authority. That it afforded a measure of
justification to the free activities of the individual capitalist,
attracted to it the support of the dominant social force behind
authority.
彼の教義は、多くの社会的不公正と明らかな冷酷さを進歩の過程における避けがたいことだと説明し、そのような状況を変えようとする試みは総じて有益であるよりはむしろ有害なものだと説明したことで、権力者たちの寵愛を手に入れた。彼の教義は、個々の資本家の自由な行動を正当化する手段を与えたことで、権力の後ろにいる社会の支配層の支持をも獲得した。
But although the doctrine itself has remained unquestioned by orthodox
economists up to a late date, its signal failure for purposes of
scientific prediction has greatly impaired, in the course of time, the
prestige of its practitioners. For professional economists after
Malthus were apparently unmoved by the lack of correspondence between
the results of their theory and the facts of observation;― a
discrepancy which the ordinary man has not failed to observe, with the
result of his growing unwillingness to accord to economists that
measure of respect which he gives to other groups of scientists whose
theoretical results are confirmed by observation when they are applied
to the facts.
しかしながら、教義自体は最近まで正統派経済学者たちから何ら問題視されることなく存続したにもかかわらず、科学的予見で明らかに失敗したため、実際的な信用は大きく失われて行った。というのは、マルサス以降のプロの経済学者たちは、自分たちの理論と観察的事実の間につながりがないことを気にしなかったように見えるが、この食い違いは一般の目には明らかだったからである。他の分野の科学者がその理論的結果を事実に適用して、観察によって確認することで一般の尊敬をかち得たのに対して、経済学者はそのような尊敬を得ることはなかったのである。
The celebrated optimism of traditional economic theory, which has led
to economists being looked upon as Candides, who, having left this
world for the cultivation of their gardens, teach that all is for the
best in the best of all possible worlds provided we will let well
alone（現状のままにしておく）, is also to be traced, I think, to their having
neglected to take account of the drag on prosperity which can be
exercised by an insufficiency of effective demand.
伝統的な経済理論のよく知られた楽観主義のおかげで、経済学者たちはカンディード（＝ヴォルテール作）たちであると言われるようになっていた。彼らは自分たちだけの庭を耕すためにこの世を捨てて、現状をあるがままに認めさえすれば最善の世界において全てが最善の結果を迎えると教えているのである。この楽観主義の起源もまた元をたどれば、有効需要の不足が繁栄の足を引っ張る可能性に当時の経済学者たちが一顧だにしなかったことによると思われる。
For there would obviously be a natural tendency towards the optimum
employment of resources in a Society which was functioning after the
manner of the classical postulates. It may well be that the classical
theory represents the way in which we should like our Economy to
behave. But to assume that it actually does so is to assume our
difficulties away.
というのは、古典派の公理のとおりに機能する「社会」では、自然に任せておけば人的資源の最適雇用が実現されることが明白だからである。おそらく古典派の理論は「経済」にどのような振舞いをして欲しいかを表わしたものなのだろう。しかしながら、実際の経済がそのように振舞うと想定するのは、この世の中に困難など存在しないと想定することと同じことなのである。
Author's Footnotes
[1]. A precise definition of user cost will be given in Chapter 6.
[2]. Not to be confused (vide infra) with the supply price of a unit of output in the ordinary sense of this term.
[3]. The reader will observe that I am deducting the user cost both
from the proceeds and from the aggregate supply price of a given volume
of output, so that both these terms are to be interpreted net
of（除いた、差し引いた、含めない） user cost; whereas the aggregate sums paid by the
purchasers are, of course, gross of（含めた） user cost. The reasons why
this is convenient will be given in Chapter 6. The essential point is
that the aggregate proceeds and aggregate supply price net of user cost
can be defined uniquely（一意に） and unambiguously; whereas, since user
cost is obviously dependent both on the degree of integration of
industry and on the extent to which entrepreneurs buy from one another,
there can be no definition of the aggregate sums paid by purchasers,
inclusive（＝gross） of user cost, which(＝先行詞はdefinition) is independent
of these factors. There is a similar difficulty even in defining supply
price in the ordinary sense for an individual producer; and in the case
of the aggregate supply price of output as a whole serious difficulties
of duplication are involved, which have not always been faced. If the
term is to be interpreted gross of user cost, they can only be overcome
by making special assumptions relating to the integration of
entrepreneurs in groups according as they produce consumption-goods or
capital-goods<,> which are obscure and complicated in themselves
and do not correspond to the facts. If, however, aggregate supply price
is defined as above net of user cost, the difficulties do not arise.
The reader is advised, however, to await the fuller discussion in
Chapter 6 and its appendix.
[4]. An entrepreneur, who has to reach a practical decision as to his
scale of production, does not, of course, entertain a single undoubting
expectation of what the sale-proceeds of a given output will be, but
several hypothetical expectations held with varying degrees of
probability and definiteness. By his expectation of proceeds I mean,
therefore, that expectation of proceeds which, if it were held with
certainty, would lead to the same behaviour as does the bundle of vague
and more various possibilities which actually makes up his state of
expectation when he reaches his decision.
[5]. In Chapter 20 a function closely related to the above will be called the employment function.
[6]. Defined in Chapter 10, below.
著者注
[１] 使用費用の正確な定義は第６章で行われる。
[２] 用語の普通の意味での産出単位の供給価格と混同してはならない（下記を見よ）。
[３] 読者はお気づきだろうが、私は所与の量の産出物の「売上」にも「総供給価格」（＝Ｚ）にも使用費用を含めていない。だから、買い手が支払う総額に
は当然使用費用が含まれることになるが、「売上」と「総供給価格」の項目は使用費用を含まない「正味」の額と解釈してもらいたい。こうするのが便利な理由は第６章で明らかにされる。要するに、使用費用を含めないほうが総売上と総供給価格を曖昧ではなく一意に定義できるのである。その一方で、使用費用は産業の統合度や起業家たちの間の売り買いの程度で明らかに違ってくるので、こうした要素を別にして買い手の支払い総額を定義することは不可能である。支払総額には必ず使用費用が含まれているのである。個々の生産者にとって普通の意味での供給価格を定義するのさえ同じくらい難しい。これまではあまり直視されなかったが、産出物全体の総供給価格の場合には二重計算という深刻な問題がある。もしこの項目を使用費用込みで解釈したければ、二重計算の問題を克服するために、企業家たちが消費財を製造するか資本財を製造するかにしたがってグループ別に統合されているという特殊な想定をするほかないが、これは曖昧で複雑であり事実にも反している。しかし、もし総供給価格を上記のように使用費用を含めず定義するなら、二重計算の問題は発生しない。しかし、これについての本格的な議論は第６章とその付録まで待ってほしい。
[４] もちろん、生産規模を実際に決めなければならない企業家は、一定の産出物の販売売上について明確なただ一つの予想値をもっているわけではなく、様々な仮定に基づく複数の予想値を持っているのであって、それらの蓋然性や確からしさも様々である。だから、わたしが言う「企業家の売上の予想値」とは、彼が決断するときにそれが確信を伴う場合であろうと、実際に予想される状況がもっと多様な可能性の集まりで漠然としている場合であろうと、同じ行動に導くようなものである。★
[５] 第２０章では上記の関数と密接につながりを持つ関数が雇用関数と呼ばれることになる。
[６] のちに第１０章で定義される。
Book II Definitions and Ideas
第２巻 定義と概念
Chapter 4. The Choice of Units
第４章 単位の選択
I
IN this and the next three chapters we shall be occupied with an
attempt to clear up certain perplexities which have no peculiar or
exclusive relevance to the problems which it is our special purpose to
examine. Thus these chapters are in the nature of a digression, which
will prevent us for a time from pursuing our main theme. Their
subject-matter is only discussed here because it does not happen to
have been already treated elsewhere in a way which I find adequate to
the needs of my own particular enquiry.
第１節
この章と次の三つの章では、ある種の困難を解決することに充てられる。これは我々がいま検討しようとしている問題とは特に何の関連性も持たない。したがっ
て、以下の章は一種の脱線であり、我々のテーマからはしばらく外れることになる。こんな問題を私がここで扱うのは、私のこの研究の必要性を満たすほど充分
に検討されたことがないからにすぎない。
The three perplexities which most impeded my progress in writing this
book, so that I could not express myself conveniently until I had found
some solution for them, are: firstly, the choice of the units of
quantity appropriate to the problems of the economic system as a whole;
secondly, the part played by expectation in economic analysis; and,
thirdly, the definition of income.
私がこの本を書き進めるにあたって障碍となった問題は三つあって、その解決策を見つけるまで、私は自分の考えをうまく表わすことが出来なかった。問題の第
一は、経済全体の問題を扱うのに相応しい数量単位の選択であり、第二は経済分析における予想値のはたす役割、第三は所得の定義である。
II
That the units, in terms of which economists commonly work, are
unsatisfactory can be illustrated by the concepts of the National
Dividend, the stock of real capital and the general price-level:―
(i) The National Dividend, as defined by Marshall and Professor
Pigou,[1] measures the volume of current output or real income and not
the value of output or money-income.[2] Furthermore, it depends, in
some sense, on net output; ― on the net addition, that is to say, to
the resources of the community available for consumption or for
retention as capital stock, due to the economic activities and
sacrifices of the current period, after allowing for（＝考慮に入れる、含める） the
wastage（損耗費） of the stock of real capital existing at the commencement
of the period.
第２節
経済学者が仕事をするときによく使う単位が不充分なものであることは、例えば国民分配分、実物資本ストック、一般物価水準などの概念を見ればよくわかる。
（ｉ）国民分配分は、マーシャルとピグー教授[１]の定義によれば、当期の産出高や実質所得（＝実質国民所得）を表すもので、産出物の価格や名目所得を表
すものではない[２]。さらに、国民分配分を決めるのは純産出量であり、純産出量とは、消費にも使えるし資本の蓄積にも使える社会資源への純追加分であ
る。この純追加分は当期の経済活動と出費から算出されるものであり、期間の初めに存在した実物資本ストックの損耗分も含まれる。
On this basis an attempt is made to erect a quantitative science. But
it is a grave objection to this definition for such a purpose that the
community's output of goods and services is a non-homogeneous complex
which cannot be measured, strictly speaking, except in certain special
cases, as for example when all the items of one output are included in
the same proportions in another output.
この国民分配分の定義を基礎にして、数量科学を打ち建てる試みがなされているのだ。しかし、そんな目的を目指すにはこの定義には深刻な欠点がある。という
のは、社会の財とサービスという産出物は同次性（＝変数をｋ倍すると関数値もｋ倍になる）のない複合物であり、それを数量的に計測することは、厳密に言え
ば、例えばある産出物の中の全項目が他の産出物の中に同じ割合で含まれているという特殊な場合以外には不可能だからである。
(ii) The difficulty is even greater when, in order to calculate net
output, we try to measure the net addition to capital equipment; for we
have to find some basis for a quantitative comparison between the new
items of equipment produced during the period and the old items which
have perished by wastage.
(ｉｉ) 純産出量を計算するために資本設備に対する純追加分を計算しようとすると、困難はさらに増大する。というのは、この期間中に作られた新しい設備の項目と消耗して失われた古い設備の項目とを数量的に比較する何らかの基準を見つけなければならないからである。
In order to arrive at the net National Dividend, Professor
Pigou[3] deducts such obsolescence,（陳腐化、老朽化、旧式化） etc., “as may fairly
be called 'normal'; and the practical test of normality is that the
depletion（消耗） is sufficiently regular to be foreseen, if not in detail,
at least in the large.” But, since this deduction is not a deduction in
terms of money, he is involved（巻き込まれて） in assuming that there can be a
change in physical quantity, although there has been no physical
change; i.e. he is covertly（こっそり） introducing changes in value.
ピグー教授[３]は純国民分配分を算出するに際して、「旧式化した」など「通常の消耗と呼ぶのがふさわしい」ものは差し引いている。そして「その消耗が通
常のものであるかどうかは、消耗が異常なものではなく、その詳細を見通せなくても大体は予想がつくものである」と言うのである。しかし、この控除は金額に
よるものではないので、彼は物に変化がなくても物の量的変化が起こり得るとする想定に陥っている。つまり、彼はこっそりと値（＝収益）の変化を持ち込んで
いるのである。
Moreover, he is unable to devise any satisfactory formula[4] to
evaluate new equipment against old when, owing to changes in technique,
the two are not identical. I believe that the concept at which
Professor Pigou is aiming is the right and appropriate concept for
economic analysis. But, until a satisfactory system of units has been
adopted, its precise definition is an impossible task. The problem of
comparing one real output with another and of then calculating net
output by setting off new items of equipment against the wastage of old
items presents conundrums（難問） which permit, one can confidently say, of
no solution.
その上、彼は新しい設備と古い設備が技術の変遷で最早同じものとは言えなくなった時に両者の違いを数値化する充分な計算式[４]を作り出せないのである。
私はピグー教授の目指している概念（＝国民分配分）自体は正しいし経済の分析に相応しいものだと思う。しかし、数量単位の充分な体系が採用されるまでは、
その概念を正確に定義することは不可能である。ある実物産出量を他の実物産出量と比べて、次に古い設備項目の消耗を新しい設備項目から差し引いて純産出量
をはじき出すという問題は永遠の謎であり、その問には答えがないと自信をもって言える。
(iii) Thirdly, the well-known, but unavoidable, element of vagueness
which admittedly attends the concept of the general price-level makes
this term very unsatisfactory for the purposes of a causal analysis,
which ought to be exact.
(ｉｉｉ) 第三に、「一般物価水準」という概念に、避け難い曖昧さが付きまとうことはよく知られている。そのおかげで「一般物価水準」という言葉は、正確さを必要とする原因分析という目的には不充分なものとなっている。
Nevertheless these difficulties are rightly regarded as “conundrums.”
They are “purely theoretical” in the sense that they never perplex, or
indeed enter in any way into, business decisions and have no relevance
to the causal sequence of economic events, which are clear-cut and
determinate in spite of the quantitative indeterminacy of these
concepts. It is natural, therefore, to conclude that they not only lack
precision but are unnecessary. Obviously our quantitative analysis must
be expressed without using any quantitatively vague expressions. And,
indeed, as soon as one makes the attempt, it becomes clear, as I hope
to show, that one can get on much better without them.
それにも関わらず、いやそれだからこそ、これらの問題はまさに「謎々」と呼ぶのがふさわしいである。というのは、それらは純粋に理論的な問題であり、ビジ
ネスの決定を複雑にするどころか、それとは何の関わりもないものであり、経済現象の因果関係とも全く無関係だからである。経済現象の因果関係は上記の概念
が数量的に漠然としているにも関わらず、明瞭ではっきりしている。したがって、上記の概念は不正確であるだけでなく不必要だと結論するのが自然である。我
々の量的分析は量的に曖昧な表現を使わずに行われねばならないのは明らかである。そして、実際のところ、量的分析をしようとすれば、私が示そうとしたとお
りに、そんな概念がない方が遥かにうまく行くのである。
The fact that two incommensurable（同じ基準で測れない） collections（集合） of
miscellaneous （種々雑多なものからなる）objects（物、対象） cannot in themselves provide
the material for a quantitative analysis need not, of course, prevent
us from making approximate statistical comparisons, depending on some
broad element of judgment rather than of strict calculation, which may
possess significance and validity within certain limits. But the proper
place for such things as net real output and the general level of
prices lies within the field of historical and statistical description,
and their purpose should be to satisfy historical or social curiosity,
a purpose for which perfect precision ― such as our causal analysis
requires, whether or not our knowledge of the actual values of the
relevant quantities is complete or exact ― is neither usual nor
necessary.
もっとも、種々雑多なものからなる二つの集合を同じ基準で測ることはできないから、それ自体は数量的分析の対象にはできないとしても、この二つを統計上大
まかに比較することが不可能というわけではない。それは厳密な計算というよりは大雑把な判断材料によるもので、ある程度の範囲内でなら有意義で価値あるも
のかもしれない。しかしながら、実際の純産出量や一般物価水準のようなものにとって相応しい居場所は、歴史的で統計的な記述の領域であって、その目的は歴
史的なあるいは社会的な興味を満たすものである。そのような目的には完璧な精度は無用であり不要でもある。しかし、我々の原因分析には、関係する数量の実
際の値が正確で完全なものであるかどうかには関わらず、完璧な精度が必要なのである。
To say that net output to-day is greater, but the price-level lower,
than ten years ago or one year ago, is a proposition of a similar
character to the statement that Queen Victoria was a better queen but
not a happier woman than Queen Elizabeth ― a proposition not without
meaning and not without interest, but unsuitable as material for the
differential calculus（微分）. Our precision will be a mock（偽の） precision
if we try to use such partly vague and non-quantitative concepts as the
basis of a quantitative analysis.
「１０年前よりいや１年前よりも今日の純産出量は大きいが、物価水準は低い」などと言うことは、ヴィクトリア女王はエリザベス女王よりよい女王だったが女
としては幸せではなかったと言うのと似たような主張であり、無意味な主張でもつまらない主張でもないが、微積分の対象としては不向きである。もし我々がそ
のような漠然とした数量的でない概念を数量分析の基本として使うとしたら、我々の正確さは偽りの物となるだろう。
III
On every particular occasion, let it be remembered, an
entrepreneur is concerned with decisions as to the scale on which to
work（動かす） a given capital equipment; and when we say that the
expectation of an increased demand, i.e. a raising of the aggregate
demand function（関数の上方へのシフト？ 関数の値の増加？）, will lead to an increase in
aggregate output, we really mean that the firms, which own the capital
equipment, will be induced to associate with it a greater aggregate
employment of labour. In the case of an individual firm or industry
producing a homogeneous product we can speak legitimately, if we wish,
of increases or decreases of output. But when we are aggregating the
activities of all firms, we cannot speak accurately except in terms of
quantities of employment applied to a given equipment.
第３節
忘れてならないのは、いついかなる場合にも企業家は今ある資本設備をどの規模で動かすべきかを決めることに関心があるということである。そして、「需要の
増加（総需要関数の上方へのシフト）への予想が、総産出量の増加を導く」と我々が言う時、それは実際には「資本設備を持つ企業が、それにともなって労働の
総雇用量を増やす気になる」ということを意味する。同次性（＝既出）のある生産物を作る個々の企業や産業の場合は、必要なら産出量の増加や減少について正
確に語ることはできる。しかし、すべての企業の活動を集計しようとするなら、一定の資本設備に向けられた雇用量についてだけしか正確に語ることはできな
い。
The concepts of output as a whole and its price-level are not required
in this context, since we have no need of an absolute measure of
current aggregate output, such as would enable us to compare its amount
with the amount which would result from the association of a different
capital equipment with a different quantity of employment. When, for
purposes of description or rough comparison, we wish to speak of an
increase of output, we must rely on the general presumption that the
amount of employment associated with a given capital equipment will be
a satisfactory index of the amount of resultant output; ― the two being
presumed to increase and decrease together, though not in a definite
numerical proportion.
この目的には全産出量とかその物価水準などという概念は必要ない。というのは、我々には当期の総産出量を計測する絶対的な尺度は必要ないし、それによって
異なる資本設備と異なる雇用量の組み合わせから生まれる総産出量と現状の総産出量を比較できるようにする必要はないからである。大雑把な比較や説明が目的
で産出量の増加について語りたいときには、一定の資本設備にともなう雇用量がそこから生まれる産出量の満足な指標となるという漠然とした推測を頼りにしな
ければならない。雇用量と産出量の増減は、たとえ一定の割合ではなくても、同時に起こると考えられるからである。
In dealing with the theory of employment I propose, therefore,
to make use of only two fundamental units of quantity, namely,
quantities of money-value and quantities of employment. The first of
these is strictly homogeneous, and the second can be made so. For, in
so far as different grades and kinds of labour and salaried assistance
enjoy a more or less fixed（固定した） relative remuneration（報酬）, the
quantity of employment can be sufficiently defined for our purpose by
taking an hour's employment of ordinary labour as our unit and
weighting（加重値をつける） an hour's employment of special labour in proportion
to its remuneration; i.e. an hour of special labour remunerated at
double ordinary rates will count as two units. We shall call the unit
in which the quantity of employment is measured the labour-unit; and
the money-wage of a labour-unit we shall call the wage-unit（単位賃金）.[5]
Thus, if E is the wages (and salaries) bill, W the wage-unit, and N the
quantity of employment, E = NxW
したがって、私は雇用理論を扱うときに使用する基本的な数量単位を二つだけにすることを提案する。それは、貨幣価格量と雇用量である。このうち最初のもの
は厳密な同次性（＝既出）を持っているし、二番目のものには同次性を持たせることが出来る。というのは、異なる等級と種類の労働は相対的に固定された報酬
をもたらすため、普通の労働による１時間の雇用を１単位とし、特別な労働による１時間の雇用を報酬に応じて加重することによって、雇用量は我々の目的に
とって充分に定義可能なものとなる。つまり、普通の労働の倍の報酬をもたらす特別な労働の１時間を２単位として数えるのである。雇用量が計算される単位は
単位労働（＝時間数と考える）と呼ぶことにする。そして単位労働の名目賃金を単位賃金（＝時間あたりの賃金と考える）と呼ぶことにする[５]。そうする
と、Ｅを賃金の総額とし、Ｗを単位賃金とし、Ｎを雇用量（＝時間）とするとき、Ｅ＝Ｎ×Ｗとなる。
This assumption of homogeneity in the supply of labour is not upset by
the obvious fact of great differences in the specialised skill of
individual workers and in their suitability for different occupations.
For, if the remuneration of the workers is proportional to their
efficiency, the differences are dealt with by our having regarded
individuals as contributing to（寄与する） the supply of labour in proportion
to their remuneration; whilst if, as output increases, a given firm has
to bring in labour which is less and less efficient for its special
purposes per wage-unit paid to it, this is merely one factor among
others leading to a diminishing return from the capital equipment in
terms of output as more labour is employed on it. We subsume（包含する）, so
to speak, the non-homogeneity of equally remunerated labour-units in
the equipment, which we regard as less and less adapted to employ the
available labour-units as output increases, instead of regarding the
available labour-units as less and less adapted to use a homogeneous
capital equipment.
労働供給における同次性の仮定は、個々の労働者の特殊技術や様々な仕事への適応力に大きな違いがあるという明らかな事実によって覆されることはない。とい
うのは、労働者の報酬がその能力に比例したものなら、それらの違いは、個々の労働者はその報酬に比例して労働供給を増やしているとみなすことで対処できる
からである。一方、もし産出量が増加するにつれて、ある企業が特別な仕事に対して次第に賃金効率の落ちる労働者を投入しなければならないとしても、それは
雇用が増えるにつれて資本設備から生ずる産出物の収益が次第に減少する要因の一つにすぎない。同じ報酬を得ている労働単位のいわば非同次性を、我々は資本
設備の中に組み込むのである。そして、利用可能な労働単位が同次性のある資本設備を使用するのに益々不適合になると見るかわりに、産出量が増加するにつれ
て利用可能な労働単位を雇用するのに資本設備の方が益々不適合になると見るのである。
Thus if there is no surplus of specialised or practised labour and the
use of less suitable labour involves a higher labour cost per unit of
output, this means that the rate at which the return from the equipment
diminishes as employment increases is more rapid than it would be if
there were such a surplus.[6] Even in the limiting case where different
labour-units were so highly specialised as to be altogether incapable
of being substituted for one another, there is no awkwardness; for this
merely means that the elasticity of supply of output from a particular
type of capital equipment falls suddenly to zero when all the available
labour specialised to its use is already employed.[7] Thus our
assumption of a homogeneous unit of labour involves no difficulties
unless there is great instability in the relative remuneration of
different labour-units; and even this difficulty can be dealt with, if
it arises, by supposing a rapid liability to change（名詞） in the supply
of labour and the shape of the aggregate supply function.
だから、もし専門の労働者や熟練労働者が不足して、それより能力が落ちる労働者を使用することで、産出単位あたりの労働コストが増えたとしても、それは雇
用の増加にともなって資本設備からの収益の逓減する速度が、そのような不足がない場合よりも速くなることを意味するだけである[６]。異なる労働単位が高
度に専門化して互いに代用することが不可能であるという限定的な場合でも、困ることはない。なぜなら、それは、特殊なタイプの資本設備に特化された労働力
が全員雇用済みになったとき、その設備からの産出物の供給が急に弾力性を失うことを意味するにすぎないからである[７]。つまり、労働単位が同次性を持つ
という我々の仮定には何の問題もない。ただし、異なる労働単位の相対的な報酬がまったく固定されない場合には話は別であるが、この問題が生じる場合も、労
働供給と総供給関数の形は変化を受けやすいと考えることで対処できる。
It is my belief that much unnecessary perplexity can be avoided
if we limit ourselves strictly to the two units, money and labour, when
we are dealing with the behaviour of the economic system as a whole;
reserving the use of units of particular outputs and equipments to the
occasions when we are analysing the output of individual firms or
industries in isolation; and the use of vague concepts, such as the
quantity of output as a whole, the quantity of capital equipment as a
whole and the general level of prices, to the occasions when we are
attempting some historical comparison which is within certain (perhaps
fairly wide) limits avowedly unprecise and approximate.
もし我々が経済全体の振る舞いを分析するときに使う単位を貨幣と労働の二つに厳密に限定するなら、不必要な複雑さを回避できるというのが私の信念である。
特別な産出量と資本設備の単位を使うのは、個別の企業や産業を他から切り離して分析するときのために残しておけばよいのである。また、産出量全体の量とか
資本設備全体の量とか一般物価水準といった曖昧な概念を使うのは歴史的な比較をする時にとっておけばいいのである。そのような比較がかなりの程度で精度を
欠いたおおまかなものであることは明らかだからである。
It follows that we shall measure changes in current output by
reference to the number of hours of labour paid for (whether to satisfy
consumers or to produce fresh capital equipment) on the existing
capital equipment, hours of skilled workers being weighted in
proportion to their remuneration. We have no need of a quantitative
comparison between this output and the output which would result from
associating a different set of workers with a different capital
equipment. To predict how entrepreneurs possessing a given equipment
will respond to a shift in the aggregate demand function it is not
necessary to know how the quantity of the resulting output, the
standard of life and the general level of prices would compare
with（～は～と比べてどうである） what they were at a different date or in another
country.
したがって、我々は当期の産出量の変化を（消費者の欲望を満たすか新たな資本設備を生み出すために）現状の資本設備もとで賃金を支払われた労働時間数に
よって計測することにする。その場合、熟練労働者の時間はその報酬に比例した加重値が付加される。このようにして計測した総産出量を、これとは異なる資本
設備と労働者の組み合わせから生まれる総産出量と量的に比較する必要はない。ある資本設備を持つ企業家たちが総需要関数のシフトにどのように反応するかを
予測するには、その設備から生まれる産出量と生活水準と一般物価水準が、別の時期や別の国であればどうなるかを知る必要はないのである。
IV
It is easily shown that the conditions of supply, such as are
usually expressed in terms of the supply curve, and the elasticity of
supply relating output to price, can be handled in terms of our two
chosen units by means of the aggregate supply function, without
reference to quantities of output, whether we are concerned with a
particular firm or industry or with economic activity as a whole. For
the aggregate supply function for a given firm (and similarly for a
given industry or for industry as a whole) is given by
Zr = φr(Nr),
第４節
容易に示されるように、供給の状態（一般に供給曲線によって描かれる）と産出供給の価格弾力性は、我々が選んだ二つの単位（＝貨幣と労働、ＺとＮ）を使っ
た総供給関数（＝φ）によって扱うことができる。この場合、産出量に言及する必要はないし、我々の扱うものが個別の企業であろうと産業であろうと経済活動
全体であろうと関係はない。というのは、ある企業（ある産業でも産業全体でも同じ）の総供給関数は
Ｚｒ ＝ φｒ(Ｎｒ),
で与えられるからである（＝ここで添字ｒがr産業の数字であることを示すことは第２０章冒頭にある。Ｘｗについて後出）。
where Zr is the proceeds (net of user cost) the expectation of which
will induce a level of employment Nr. If, therefore, the relation
between employment and output is such that an employment Nr results in
an output Or, where Or = ψr(Nr), it follows that
p = {Zr + Ur(Nr)}/Or = {φr(Nr) + Ur(Nr)}/ψr(Nr)
is the ordinary supply curve, where Ur(Nr) is the (expected) user cost corresponding to a level of employment Nr.
ここでＺｒは売上（使用費用を含めない）であり、それに対する予想が雇用レベルＮｒを誘発する。したがって、もし雇用と産出量の関係が、産出量Ｏｒが雇用Ｎｒの結果であるとし、Ｏｒ＝ψｒ（Ｎｒ）であるとすると、ここから
ｐ＝{Ｚｒ＋Ｕｒ(Ｎｒ)}／Ｏｒ＝{φｒ(Ｎｒ)＋ Ｕｒ(Ｎｒ)}／ψｒ(Ｎｒ)（＝単位産出量あたりの価格）
が通常の供給曲線となる。ここでＵｒ(Ｎｒ)は雇用レベルＮｒに対する（予想された）使用費用である。
Thus in the case of each homogeneous commodity, for which Or = ψr(Nr)
has a definite meaning, we can evaluate Zr = φr(Nr) in the ordinary
way; but we can then aggregate the Nr's in a way in which we cannot
aggregate the Or's, since ΣOr is not a numerical quantity. Moreover, if
we can assume that, in a given environment, a given aggregate
employment will be distributed in a unique way between different
industries, so that Nr is a function of N, further simplifications are
possible.
つまり、同次性のある個々の商品の場合には、Ｏｒ＝ψｒ(Ｎｒ)が明確な意味を持つので、Ｚｒ＝
φｒ(Ｎｒ)を通常の方法で評価できる。しかし、その際、Ｎｒの合計は数字で出すことができるが、ΣＯｒ（＝Ｏｒの総和）は数字で表される量ではないの
で、Ｎｒと同じ様にＯｒの合計を数字で出すことは出来ない。さらに、もしある一定の環境のもとで一定の総雇用が様々な産業間に明確な仕方で配分されて、そ
の結果ＮｒはＮの関数であると想定できるなら、これらはもっと単純化することが出来る。
Author's Footnotes
[1]. Vide Pigou, Economics of Welfare, passim, and particularly Part I. chap. iii.
[2]. Though, as a convenient compromise, the real income, which is
taken to constitute the National Dividend, is usually limited to those
goods and services which can be bought for money.
[3]. Economics of Welfare, Part I. chap. v., on “What is meant by
maintaining Capital intact”; as amended by a recent article in the
Economic Journal, June 1935, p. 225.
[4]. Cf. Prof. Hayek's criticisms, Economica, Aug. 1935, p. 247.
[5]. If X stands for any quantity measured in terms of money, it will
often be convenient to write Xw for the same quantity measured in terms
of the wage-unit.
[6]. This is the main reason why the supply price of output rises with
increasing demand even when there is still a surplus of equipment
identical in type with the equipment in use. If we suppose that the
surplus supply of labour forms a pool equally available to all
entrepreneurs and that labour employed for a given purpose is rewarded,
in part at least, per unit of effort and not with strict regard to its
efficiency in its actual particular employment (which is in most cases
the realistic assumption to make), the diminishing efficiency of the
labour employed is an outstanding example of rising supply price with
increasing output, not due to internal diseconomies.
[7]. How the supply curve in ordinary use is supposed to deal with the
above difficulty I cannot say, since those who use this curve have not
made their assumptions very clear. Probably they are assuming that
labour employed for a given purpose is always rewarded with strict
regard to its efficiency for that purpose. But this is unrealistic.
Perhaps the essential reason for treating the varying efficiency of
labour as though it belonged to the equipment lies in the fact that the
increasing surpluses, which emerge as output is increased,
accrue（動詞、～に生ずる） in practice mainly to the owners of the equipment and
not to the more efficient workers (though these may get an advantage
through being employed more regularly and by receiving earlier
promotion); that is to say, men of differing efficiency working at the
same job are seldom paid at rates closely proportional to their
efficiencies. Where, however, increased pay for higher efficiency
occurs, and in so far as it occurs, my method takes account of it;
since in calculating the number of labour-units employed, the
individual workers are weighted in proportion to their remuneration. On
my assumptions interesting complications obviously arise where we are
dealing with particular supply curves since their shape will depend on
the demand for suitable labour in other directions. To ignore these
complications would, as I have said, be unrealistic. But we need not
consider them when we are dealing with employment as a whole, provided
we assume that a given volume of effective demand has a particular
distribution of this demand between different products uniquely
associated with it（＝have A doneの構文）.
著者注
[１] ピグー『厚生経済学』、特に第１部３章。
[２] もっとも、国民分配分を構成するとみなされる実質所得（＝実質国民所得）は通常はお金で買える財とサービスに限られており、これが便利な解決策となっている。
[３] 『厚生経済学』第１部第５章「資本を無傷で維持するとはどういう事か」。最近の論文（『エコノミック・ジャーナル』１９３５年６月２２５頁）で修正されている。
[４] ハイエク教授の批判（『エコノミカ』１９３５年８月２４７頁）参照。
[５] もしＸがお金で計測した量なら、同じ量を単位賃金で計測したものはＸｗと書くのが、多くの場合、便利だろう。
[６] 使用中の資本設備と同じタイプの設備が余っている時でも、需要が増加するにつれて産出物の供給価格が上昇する主な理由はこれである。余っている労
働力の供給がすべての企業家にとって公平に利用可能なようにプールされており（＝有能な労働者だけを選べない）、ある目的で雇用された労働力の報酬が、少
なくも一部は単位労働ごとに支払われ、実際の個々の仕事の能率に厳密に対応するものではない（多くの場合これは現実的な想定である）と考えると、雇用され
た労働力の効率が減少することは、産出量が増加するにつれて供給価格が上昇するのが内部不経済（＝企業活動の拡大に伴うコストの増加）のせいではないこと
の明らかな証拠である。
[７] 一般に使われている供給曲線（＝上記のＺ =
φ(Ｎ)ではない産出量と価格のグラフ）がこの問題（＝専門の労働者が全員雇用済みの場合）をどう扱うつもりでいるかを私は知らない。なぜなら、この曲線
を使っている人たちが自分たちの意図を明らかにしていないからである。おそらく彼らは、ある目的で雇用された労働者は常に仕事の能率に厳密に対応する報酬
を得ていると考えているのだろう。しかし、これは現実的ではない。多分、能率の異なる労働者たちを資本設備と一体であるかのように扱う方がよいと考えるべ
き主な理由は、産出量の増加につれて増加する剰余利得は実際には主に設備の所有者のものになって能率の高い労働者のものにはならないという事実にある
（もっとも彼らは正規に雇用されたり昇進が早まったりすることで得をするが）。つまり、作業能率が異なるのに同じ仕事をしている労働者たちがその能率に厳
密に比例した報酬を得ていることはめったにないのである。もっとも、私の方法は、高い能率に対して高い報酬が支払われている場合も、それが起こる限りは考
慮に入れている。というのは、雇用された単位労働の数を計算するときに、個々の労働者にその報酬に比例した加重値を付加するからである。私の想定では個々
の供給曲線を扱おうとする場合には興味深い難問が当然起こってくる。というのはそれらの曲線の形を決めるのはその仕事に向いていない人への需要だからであ
る（＝向いている人は全員雇用済みだから）。この問題を無視するのは、いま言ったように、現実的ではないだろう。しかし、雇用を全体として考える場合には
この問題を検討する必要はない。ただし、この場合には所与の量の有効需要は、様々な生産物の間へ特別な仕方で配分されていて、しかもその配分の仕方以外に
はないと想定されている（＝第２０章第４段落に再出）。
It may be, however, that this would not hold good irrespective
of the particular cause of the change in demand. E.g. an increase in
effective demand due to an increased propensity to consume might find
itself faced by a different aggregate supply function from that which
would face an equal increase in demand due to an increased inducement
to invest. All this, however, belongs to the detailed analysis of the
general ideas here set forth, which it is no part of my immediate
purpose to pursue.
しかしながら、この想定は需要の変化の特殊な原因と関係なく有効といういわけではない。例えば、消費性向の増大に起因する有効需要の増加が直面する総供給
関数は、投資インセンティブの増大に起因する有効需要の同じだけの増加が直面する総供給関数とは異なっているかもしれない。しかし、これらのことは、ここ
で示した一般的な考え方を詳細に分析するときに関係してくることばかりで、私の当面の目的とは関係がない。
Chapter 5. Expectation as Determining Output and Employment
第５章 産出量と雇用を決めるものとしての予想
I
ALL production is for the purpose of ultimately satisfying a
consumer. Time usually elapses, however ― and sometimes much time ―
between the incurring of costs by the producer (with the consumer in
view) and the purchase of the output by the ultimate consumer.
Meanwhile the entrepreneur (including both the producer and the
investor in this description) has to form the best expectations[1] he
can as to what the consumers will be prepared to pay when he is ready
to supply them (directly or indirectly) after the elapse of what may be
a lengthy period; and he has no choice but to be guided by these
expectations, if he is to produce at all by processes which occupy time.
第１節
全ての生産の最終的な目的は消費者の欲望を満たすことである。しかし、生産者が（消費者を視野に入れて）コストを負担してから最終的に産出物を消費者が購
入するまでの間には、時間がそれもしばしば非常に長い時間がかかる。その間に企業家（これには生産者と投資家の両方を含まれる）は、その長い時間がたった
あとで産出物を（直接間接に）供給できるようになった時に、消費者がどれだけの金額を出そうとするかに関して予想[１]をうまく形成しなければならない。
もし企業家が長い時間のかかる生産活動をしようとすれば、この予想を道案内とするしかないのである。
These expectations, upon which business decisions depend, fall into two
groups, certain individuals or firms being specialised in the business
of framing the first type of expectation and others in the business of
framing the second. The first type is concerned with the price which a
manufacturer can expect to get for his “finished” output at the time
when he commits himself to starting the process which will produce it;
output being “finished” (from the point of view of the manufacturer)
when it is ready to be used or to be sold to a second party. The second
type is concerned with what the entrepreneur can hope to earn in the
shape of future returns if he purchases (or, perhaps, manufactures)
“finished” output as an addition to his capital equipment. We may call
the former short-term expectation and the latter long-term expectation.
ビジネスの決断が拠り所とするこうした予想は二つのタイプに分かれる。個人や会社でも第一のタイプの予想形成に専念しているものと、第二のタイプの予想形
成に専念しているものがある。第一のタイプは予想とは、生産者の予想で、「完成した」産出物によって得られると予想できる価格を製造開始時点で予測するも
のである。産出物が「完成した」とは（生産者の立場から見て）他人が使える或いは他人に売れる状態になっていることである。第二のタイプの予想とは、投資
家の予想で、企業家が「完成した」産出物を自分の資本設備に追加購入（あるいは製造）する場合（＝設備投資）に、将来の収益として予想できる額を予測する
ものである。我々は前者を短期予想、後者を長期予想と呼ぶことにする。
Thus the behaviour of each individual firm in deciding its daily[2]
output will be determined by its short-term expectations ― expectations
as to the cost of output on various possible scales and expectations as
to the sale-proceeds of this output; though, in the case of additions
to capital equipment and even of sales to distributors, these
short-term expectations will largely depend on the long-term (or
medium-term) expectations of other parties. It is upon these various
expectations that the amount of employment which the firms offer will
depend.
したがって、個々の企業が日々[２]の産出量を決めるときの行動は短期予想によって決まるのである。この短期予想は可能性のある様々な規模の産出量のコス
トの予測と、その産出量から得られる販売の売上予測である。もっとも、複数の資本設備への追加の場合はもちろんのこと、卸売業者への販売の場合でさえ、こ
れらの短期予想は他者（＝買い手の）の長期（あるいは中期）予想に大きく左右される。企業はこうした様々な予想に基づいて雇用量を決めるのである。
The actually realised results of the production and sale of output will
only be relevant to employment in so far as they cause a modification
of subsequent expectations. Nor, on the other hand, are the original
expectations relevant, which led the firm to acquire the capital
equipment and the stock of intermediate products and half-finished
materials with which it finds itself at the time when it has to decide
the next day's output. Thus, on each and every occasion of such a
decision, the decision will be made, with reference indeed to this
equipment and stock, but in the light of the current expectations of
prospective costs and sale-proceeds.
産出物の生産と販売から実際に実現された結果が雇用に影響してくるのは、これがその後の予想に変化をもたらす場合に限られている。その一方で、企業が翌日
の産出量を決めるときには、手元にある中間生産品や半完成品のストックと資本設備の入手を促した元の予測はもう重要ではない。つまり、そのような決断は、
その都度その都度、この資本設備やストックについて、将来のコストと販売売上に関する現在の予想を考慮して行われるのである。
Now, in general, a change in expectations (whether short-term or
long-term) will only produce its full effect on employment over a
considerable period. The change in employment due to a change in
expectations will not be the same on the second day after the change as
on the first, or the same on the third day as on the second（＝not A or
Bの構文）, and so on, even though there be no further change in
expectations.
ところで、一般に、（短期であれ長期であれ）予想の変化が充分に雇用に影響するまでには、かなり長い期間を要するものである。予想の変化による雇用の変化
は、予想の変化後二日目にはもう一日目と同じではないし、三日目は二日目と同じではない。このような繰り返しである。つまり、予想に変化がなくても雇用は
変化し続けるのである。
In the case of short-term expectations this is because changes
in expectation are not, as a rule, sufficiently violent or rapid, when
they are for the worse, to cause the abandonment of work on all the
productive processes which, in the light of the revised expectation, it
was a mistake to have begun; whilst, when they are for the better, some
time for preparation must needs elapse before employment can reach the
level at which it would have stood if the state of expectation had been
revised sooner.
その理由は短期予想の場合、予想は普通それほど急激にはも急速にも変化しないしからである。だから、予想が悪化した場合、作りなおされた予想から見れば生
産を始めたのが失敗だとわかっても、その生産の全過程の雇用を取りやめることにはならないし、予想が好転した場合でも、もっと早く予想を改めていれば到達
していたはずの雇用レベルに至るには準備期間が必要なのである。
In the case of long-term expectations, equipment which will not
be replaced will continue to give employment until it is worn out;
whilst when the change in long-term expectations is for the better,
employment may be at a higher level at first, than it will be after
there has been time to adjust the equipment to the new situation.
長期予想の場合には、資本設備が(途中で取り替えられない限り)消耗するまでの間ずっと雇用がもたらされ続ける。その一方、長期予想が好転した場合には、雇用レベルが高くなるが、その後、設備が新しい状況に適応すると雇用が減少することがある。
If we suppose a state of expectation to continue for a
sufficient length of time for the effect on employment to have worked
itself out so completely that there is, broadly speaking, no piece of
employment going on<,> which would not have taken place if the
new state of expectation had always existed, the steady level of
employment thus attained may be called the long-period employment[3]
corresponding to that state of expectation. It follows that, although
expectation may change so frequently that the actual level of
employment has never had time to reach the long-period employment
corresponding to the existing state of expectation, nevertheless every
state of expectation has its definite corresponding level of
long-period employment.
ある一定の予想が長く続いて、その予想が雇用に及ぼす効果が完全に出尽くして、概してもはやどんな雇用も起こらなくなってしまう（新しい予想が常に存在す
る場合にはそうはならないという）場合を想定すると、こうして到達された雇用の安定した段階をその予想に対応する「長期雇用」[３]と呼ぶことができる。
したがって、たとえ予想がしばしば変化して、実際の雇用レベルが現状の予想に対応する長期雇用に達する時間がなかったとしても、それぞれの予想の状態には
それぞれに見合った明確な長期雇用のレベルが存在するということになる。
Let us consider, first of all, the process of transition to a
long-period position due to a change in expectation, which is not
confused or interrupted by any further change in expectation. We will
first suppose that the change is of such a character that the new
long-period employment will be greater than the old. Now, as a rule, it
will only be the rate of input which will be much affected at the
beginning, that is to say, the volume of work on the earlier stages of
new processes of production, whilst the output of
consumption-goods（＝消費財） and the amount of employment on the later
stages of processes which were started before the change will remain
much the same as before. In so far as there were stocks of partly
finished goods, this conclusion may be modified; though it is likely to
remain true that the initial increase in employment will be modest.
そこでまず最初に、予想の変化によって雇用が長期の局面へ移行して、もはや予想のさらなる変化によって雇用が乱れたり中断したりしないようになるまでの過
程を考えてみよう。初めに、我々はその予想の変化によって新たな長期雇用が以前の長期雇用よりも大きくなる場合を考えてみよう。そうすると、普通、最初に
その予想の変化によって大きな影響を受けるのは投入率、即ち新たな生産過程の初期段階に投入される労働量だろう。一方、予想の変化が起きる前に開始した生
産過程の後期段階での消費財の産出量と雇用量は、それまでと殆ど変わることがないだろう。半完成品のストックがある場合には、この結論は修正される可能性
がある。もっとも、当初の雇用の増加はささやかであるという事実は変わらないだろう。
As, however, the days pass by, employment will gradually increase.
Moreover, it is easy to conceive of conditions which will cause it to
increase at some stage to a higher level than the new long-period
employment. For the process of building up capital to satisfy the new
state of expectation may lead to more employment and also to more
current consumption than will occur when the long-period position has
been reached. Thus the change in expectation may lead to a gradual
crescendo in the level of employment, rising to a peak and then
declining to the new long-period level.
しかし、日がたつに連れて雇用は次第に上昇する。しかも、ある段階で新たな長期雇用より高いレベルまで雇用が上昇するような事態も容易に想像できる。とい
うのは、新たな予想を満たすために資本を強化する過程で、長期の局面に達する時よりも大きな雇用と現行消費の増加が同時に起きるからである。このように、
予想の変化は雇用レベルを徐々に増加させて、一度ピークに達してから、新たな長期雇用にまで下がっていくのである。
The same thing may occur even if the new long-period level is the same
as the old, if the change represents a change in the direction of
consumption which renders certain existing processes and their
equipment obsolete. Or again, if the new long-period employment is less
than the old, the level of employment during the transition may fall
for a time below what the new long-period level is going to be. Thus a
mere change in expectation is capable of producing an oscillation（変動）
of the same kind of shape as a cyclical movement, in the course of
working itself out. It was movements of this kind which I discussed in
my Treatise on Money in connection with the building up or the
depletion of stocks of working and liquid capital consequent on change.
たとえ新たな長期雇用が以前の長期雇用と同レベルであっても、これと同じことが起きる。それは起こった変化が、生産過程とその設備を時代遅れにするような
消費の変化である場合である。あるいはまた、もし新たな長期雇用が以前の長期雇用よりも低い場合には、移行期間の雇用レベルが新たな長期雇用のレベルより
も一時的に下回ることもある。つまり、たった一度の予想の変化も、それが効果を発揮し終えるまでには、周期的変動と同じような変動が起きるのである。予想
の変化によって起きる運転資本ストックと流動資本ストックの増減に関して『貨幣論』の中で私が述べたのはこの種の変動なのである。
An uninterrupted process of transition, such as the above, to a new
long-period position can be complicated in detail. But the actual
course of events is more complicated still. For the state of
expectation is liable to constant change, a new expectation being
superimposed long before the previous change has fully worked itself
out; so that the economic machine is occupied at any given time with a
number of overlapping activities, the existence of which is due to
various past states of expectation.
このように、新たな長期の局面への連続的な移行過程は詳しく見ると非常に複雑なようだが、実際の進展はさらに複雑である。というのは、予想の状態は常に変
化しやすいものなので、その前の変化が効果を発揮し終える前に新たな予想が始まってしまうからである。経済システムの中ではいつでも多くの動きが同時進行
しているが、それらの動きは過去の様々な予想によって始まったものなのである。
II
This leads us to the relevance of this discussion for our present
purpose. It is evident from the above that the level of employment at
any time depends, in a sense, not merely on the existing state of
expectation but on the states of expectation which have existed over a
certain past period. Nevertheless past expectations, which have not yet
worked themselves out, are embodied in the to-day's capital equipment
with reference to which the entrepreneur has to make to-day's
decisions, and only influence his decisions in so far as they are so
embodied. It follows, therefore, that, in spite of the above, to-day's
employment can be correctly described as being governed by to-day's
expectations taken in conjunction with to-day's capital equipment.
第２節
ここでこれまでの議論が我々の現在の目的につながってくる。いつの時点の雇用レベルも現在の予想の状態だけでなく過去のある期間に存在した予想の状態にも
依存していることが、いまの議論で明らかだろう。とはいえ、過去の予想がその効果をまだ発揮し終えていないとしても、それは今日の資本設備の中に体現され
ているのであり、その設備について企業家は今日の決断をするのである。つまり、過去の予想は今日の設備に体現されている範囲内で企業家の決断に影響するの
である。したがって、これまでの複雑な議論に関わらず、結局のところ、今日の雇用を決めるものは今日の資本設備と結びついた今日の予想であると言うのが正
しいのである。
Express reference to current long-term expectations can seldom be
avoided. But it will often be safe to omit express reference to
short-term expectation, in view of the fact that in practice the
process of revision of short-term expectation is a gradual and
continuous one, carried on largely in the light of realised results; so
that expected and realised results run into and overlap one another in
their influence. For, although output and employment are determined by
the producer's short-term expectations and not by past results, the
most recent results usually play a predominant part in determining what
these expectations are.
当期の長期予想をはっきりと考慮に入れることは避けられない。しかしながら、短期予想は現実にはふつう実現された結果に影響されて常にゆっくり変化し続け
ており、そのため予想された結果と実現された結果が重なりあい互いに影響しあうことを考えると、短期予想ははっきり考慮に入れない方が安全だろう。という
のは、産出量と雇用を決めるのは生産者の短期予想であって過去の結果ではないが、間近に起きた結果が短期予想を決めるうえで常に大きな役割を演じているか
らである。
It would be too complicated to work out the expectations de novo
whenever a productive process was being started; and it would,
moreover, be a waste of time since a large part of the circumstances
usually continue substantially unchanged from one day to the next.
Accordingly it is sensible for producers to base their expectations on
the assumption that the most recently realised results will continue,
except in so far as there are definite reasons for expecting a change.
Thus in practice there is a large overlap between the effects on
employment of the realised sale-proceeds of recent output and those of
the sale-proceeds expected from current input; and producers' forecasts
are more often gradually modified in the light of results than in
anticipation of prospective changes.[4]
一つの生産過程が始まるたびに新たに予想を形成するのは面倒だし時間の無駄でもある。一日ごとではまわりの状況は殆ど変わることがないのが普通だからであ
る。だから、生産者は変化が予想される明確な理由がない限りは、間近に実現された結果がそのまま続くと考えて自分の予想を形成するのが賢明である。つま
り、当期の投入から予想される販売売上が雇用に及ぼす影響と、直近の産出物によって実現された販売売上が雇用に及ぼす影響とでは殆ど同じなのである。した
がって、生産者の予想は将来の変化への予想よりは現実の結果によって徐々に変わってくるである[４]。
Nevertheless, we must not forget that, in the case of durable
goods（耐久財、耐久消費財）, the producer's short-term expectations are based on
the current long-term expectations of the investor; and it is of the
nature of（～に似ている） long-term expectations that they cannot be checked at
short intervals in the light of realized results. Moreover, as we shall
see in Chapter 12, where we shall consider long-term expectations in
more detail, they are liable to sudden revision. Thus the factor of
current long-term expectations cannot be even approximately eliminated
or replaced by realised results.
それにもかかわらず、耐久消費財の場合には、生産者の短期予想は投資家の当期の長期予想にもとづいていることを忘れてはならない。そして、実現された結果
によって生産者の予想が短期的に変更されないのは、長期予想の性格から来ているのである。しかも、後に第１２章で長期予想についてもっと詳しく検討すると
きに見るように、長期予想は急激な変化を受けやすい。だから、当期の長期予想という要素を無視することはできないし、実現された結果によってそれを変更す
ることもできないのである。
Author's Footnotes
[1]. For the method of arriving at an equivalent of these expectations
in terms of sale-proceeds see footnote (3) to p. 24 above.
[2]. Daily here stands for the shortest interval after which the firm
is free to revise its decision as to how much employment to offer. It
is, so to speak, the minimum effective unit of economic time.
[3]. It is not necessary that the level of long-period employment
should be constant, i.e. long-period conditions are not necessarily
static. For example, a steady increase in wealth or population may
constitute a part of the unchanging expectation. The only condition is
that the existing expectations should have been foreseen sufficiently
far ahead.
[4]. This emphasis on the expectation entertained when the decision to
produce is taken, meets, I think, Mr Hawtrey's point that input and
<employment are influenced by the>（一部のテキストで脱落） accumulation of
stocks before prices have fallen or disappointment in respect of output
is reflected in a realised loss relatively to expectation. For the
accumulation of unsold stocks (or decline of forward orders) is
precisely the kind of event which is most likely to cause input to
differ from what mere statistics of the sale-proceeds of previous
output would indicate if they were to be projected without criticism
into the next period.
著者注
[１] 販売売上に関してこれらの予想値に相当するものに到達する方法については、上記脚注４★を見よ。
[２] ここでいう「日々」とは企業が提供する雇用量を変更するまでの最短の期間を意味する。それは、いわば経済的時間の有効な最小単位である。
[３] 長期雇用のレベルは一定不変である必要はない。長期の状況は静的であるとは限らないからである。例えば、不変な予想の一部が富や人口の順調な増加
によって維持されているかもしれない。長期雇用の唯一の条件は、現在の予想値がはるか以前から予見されていることだけなのである。
[４]
生産決定をするときの予想に関してこの点（＝現実の結果による修正）を強調することは、投入と雇用は在庫の蓄積によって起きるというホートリー氏の主張と
合致していると思う。彼の意見では、価格の低下が起きる前、あるいは産出量についての予想外れが予想外の実損という形で現れる前に、投入の変化が起きると
いうのである。というのは、売れ残りの在庫の蓄積（あるいは予約の減少）は、投入に変化をもたらす最も重要な出来事であり、前期の産出量から得られた販売
売上の単なる統計がそのまま無批判に次期に反映されることはないのである。
Chapter 6. The Definition of Income, Saving and Investment
第６章 所得と貯蓄と投資の定義
I. Income
DURING any period of time an entrepreneur will have sold
finished output to consumers or to other entrepreneurs for a certain
sum which we will designate as A. He will also have spent a certain
sum, designated by A1, on purchasing finished output from other
entrepreneurs. And he will end up with a capital equipment, which term
includes both his stocks of unfinished goods or working capital and his
stocks of finished goods, having a value G.
第１節 所得
企業家は完成した産出物をある期間中に消費者か他の企業家に一定の額で売り払うだろう。その値をＡとする。同時に彼は他の企業家から完成した産出物を購入
するために一定の額を支払うだろう（＝設備投資）。その値をＡ１とする。そして企業家はある資本設備を手にしてその期間を終える。資本設備には未完成品の
ストックつまり運転資本（＝経営資本）と完成品のストックの両方が含まれる。資本設備の値をＧとする。
Some part, however, of A + G - A1 will be attributable, not to the
activities of the period in question, but to the capital equipment
which he had at the beginning of the period. We must, therefore, in
order to arrive at what we mean by the income of the current period,
deduct from A + G - A1 a certain sum, to represent that part of its
value which has been (in some sense) contributed by the equipment
inherited from the previous period. The problem of defining income is
solved as soon as we have found a satisfactory method for calculating
this deduction.
しかしながら、Ａ＋Ｇ－Ａ１のいくつかの部分は当該期間における活動から生まれたものではなく、その期間が始まる時点で既に所有していた資本設備から生ま
れたものである。だから、当期の所得と考えられるものを算出するためには、「前期から引き継がれた設備が（ある意味で）寄与している部分の価値」をＡ＋Ｇ
－Ａ１から差し引かねばならない。所得を定義する問題は、この控除分を計算する方法を見つけさえすれば解決するのである。
There are two possible principles for calculating it, each of which has
a certain significance; ― one of them in connection with production,
and the other in connection with consumption. Let us consider them in
turn.
これを計算するための可能な方法は二つあって、それぞれに意義がある。その一つは生産に関するものであり、もう一つのは消費に関するものである。順番に見ていこう。
(i) The actual value G of the capital equipment at the end of the
period is the net result of the entrepreneur, on the one hand, having
maintained and improved it during the period, both by purchases from
other entrepreneurs and by work done upon it by himself, and, on the
other hand, having exhausted or depreciated it through using it to
produce output.
（ｉ）期間の終わりの実際の資本設備の値Ｇとは、他の企業家からの購入（＝Ａ１）と自分の働きによって企業家がその期間内に資本設備を維持改良した分（＝Ｂ’）から、産出物を生み出すために資本設備を消耗させてその価値を低下させた分を差し引いた結果である。
If he had decided not to use it to produce output, there is,
nevertheless, a certain optimum sum which it would have paid him to
spend on maintaining and improving it. Let us suppose that, in this
event, he would have spent B' on its maintenance and improvement, and
that, having had this spent on it, it would have been worth G' at the
end of the period. That is to say, G' - B' is the maximum net value
which might have been conserved from the previous period, if it had not
been used to produce A.
もし産出物を生み出すために資本設備を使わないと決めていた場合には、資本設備を維持改良するために支出すれば企業家の得になる最適な額がある。この場
合、彼は資本設備の維持改善のためにＢ’だけ支出したと仮定しよう。そしてこの支出の御陰でその期間の終りにはその資本設備はＧ’の価値になっているとし
よう。すると、Ｇ’－Ｂ’は、「設備がＡを生産するために使われなかった場合に前期から繰り越されたかもしない最大の純価値」ということになる。
The excess of this potential value of the equipment over G - A1 is the
measure of what has been sacrificed （出費された）(one way or another) to
produce A. Let us call this quantity, namely
(G' - B') - (G - A1),
which measures the sacrifice of value involved in the production of A,
the user cost of A. User cost will be written U.[1] The amount paid out
by the entrepreneur to the other factors of
production（＝他の生産要素＝労働者＝生産要素） in return for their services, which from
their point of view is their income, we will call the factor cost of A.
The sum of the factor cost F and the user cost U we shall call the
prime-cost of the output A.
そして、設備のこの潜在的な価値（＝前期から受け継がれた最大の資本設備の価値）がＧ－Ａ１（＝当期の最後に残った資本設備の価値）を上回る分が、（＝前期から受け継がれた資本設備のうちで）Ａを生産するために（何らかの形で）使われたものの大きさである。この数量、
（Ｇ’－Ｂ’）－（Ｇ－Ａ１）、
即ちＡを生産するために使われた価値の量を、Ａの「使用費用」と呼ぶことにしよう。この「使用費用」をＵと書くことにする[１]。また、企業家が生産要素
（＝労働者）に対してそのサービスの対価として支払った額を、Ａの「要素費用」（＝Ｆ）と呼ぶことにする。この額は生産要素の側から見ると彼らの所得とな
る。要素費用Ｆと使用費用Ｕとの合計を産出物Ａの「主要費用」と呼ぶことにする。
We can then define the income[2] of the entrepreneur as being the
excess of the value of his finished output sold during the period over
his prime-cost. The entrepreneur's income, that is to say, is taken as
being equal to the quantity, depending on his scale of production,
which he endeavours to maximise, i.e., to his gross profit in the
ordinary sense of this term;― which agrees with common sense. Hence,
since the income of the rest of the community（＝企業家以外の人達） is equal to
the entrepreneur's factor cost, aggregate income is equal to A - U.
すると、企業家の「所得」[２]とはその期間内に販売された完成済み産出物の価格（＝Ａ）が主要費用（＝Ｆ＋Ｕ）を上回る額であると定義できる（＝Ａ－Ｕ
－Ｆ、第３章第１節と同じ）。言い換えれば、生産規模に応じた額であり、企業家ができるだけ大きくしようと努める額でもある粗利潤（＝粗利益）、言葉の通
常の意味における粗利潤こそが、企業家の所得と一致するのである。そして、このことは常識にも一致する。逆に、企業家の要素費用は企業家以外の人たちの所
得であるから、「総所得（＝企業家とそれ以外の所得の合計＝売上）」はＡ－Ｕなのである。
Income, thus defined, is a completely unambiguous quantity.
Moreover, since it is the entrepreneur's expectation of the excess of
this quantity over his out-goings to the other（＝自分以外のことなので訳では省略）
factors of production which he endeavours to maximise when he decides
how much employment to give to the other factors of production, it is
the quantity which is causally significant for employment.
このように定義された所得は一切の曖昧さを含まない額である。企業家はこの所得（＝総所得）の額が生産要素への出費（＝Ｆ）を上回ることを予想するのであ
る（（Ａ－Ｕ）－Ｆ＞０）。この上回る分の予想値を最大にしようとして、企業家は生産要素に与える雇用量を決めるのである。したがって、この所得は雇用の
要因として非常に重要な数字なのである。
It is conceivable, of course, that G - A1 may exceed G' - B', so
that user cost will be negative. For example, this may well be the case
if we happen to choose our period in such a way that input has been
increasing during the period but without there having been time for the
increased output to reach the stage of being finished and sold. It will
also be the case, whenever there is positive investment, if we imagine
industry to be so much integrated that entrepreneurs make most of their
equipment for themselves. Since, however, user cost is only negative
when the entrepreneur has been increasing his capital equipment by his
own labour, we can, in an economy where capital equipment is largely
manufactured by different firms from those which use it, normally think
of user cost as being positive. Moreover, it is difficult to conceive
of a case where marginal user cost associated with an increase in A,
i.e. dU/dA, will be other than positive.
もちろん、Ｇ－Ａ１がＧ’－Ｂ’より大きくなって使用費用（＝Ｕ）がマイナス（＝－Ｕがプラス）になる事態を想定することも可能である。例えば、期間の選
び方によっては、その期間に投入が増加しても、増加された投入が完成品となって販売される段階に達するだけの時間がない場合にはそうなる可能性がある。ま
た、産業の統合（＝一貫生産）が進んで企業家たちが自分の設備の大部分を自分で作るようになって（＝Ａ１がゼロになる）、投資（＝Ａ１－Ｕ）がプラスにな
る場合にもそうなるだろう。しかし、使用費用がマイナスになるのは企業家が自分の資本設備を自分の働きによって増やし続けた場合だけなので、資本設備がそ
れを使う会社とは別の会社によって作られる経済においては、普通は使用費用はプラスになると考えられる。さらに、Ａの増加と結びついた限界使用費用、即ち
ｄＵ／ｄＡがプラスにならない場合を考えるのは難しい。
It may be convenient to mention here, in anticipation of the
latter part of this chapter, that, for the community as a whole, the
aggregate consumption (C) of the period is equal to Σ(A - A1), and the
aggregate investment (I) is equal to Σ(A1 - U). Moreover, U is the
individual entrepreneur's disinvestment (and -U his investment) in
respect of his own equipment exclusive of what he buys from other
entrepreneurs. Thus in a completely integrated system (where A1 = 0)
consumption is equal to A and investment to -U, i.e. to G - (G' - B').
The slight complication of the above, through the introduction of A1,
is simply due to the desirability of providing in a generalised way for
the case of a non-integrated system of production.
ここでこの章の後半（＝第２節 貯蓄と投資）を先取りして、次のことを述べておくのは便利かもしれない。それは、社会全体にとってその期間の「総消費
（Ｃ）」はΣ（Ａ－Ａ１）と等しく、「総投資（Ｉ）」はΣ（Ａ１－Ｕ）に等しいということである。さらに、Ｕは個々の企業家が他の企業家から購入するもの
（＝Ａ１）を除いた、彼の設備についてのマイナスの投資（－Ｕは企業家のプラスの投資）である。つまり、完全に統合された一貫生産システム（そこではＡ１
＝０）では、消費はＡと等しく、投資は－ＵつまりＧ－（Ｇ’－Ｂ’）に等しい。上記ではＡ１を導入したことで多少複雑になっているが、それは単に統合され
ていない生産システムのために一般的な方法を提示するほうが望ましいためである。
Furthermore, the effective demand is simply the aggregate income (or
proceeds) which the entrepreneurs expect to receive, inclusive of the
incomes which they will hand on to other factors of production, from
the amount of current employment which they decide to give. The
aggregate demand function relates various hypothetical quantities of
employment to the proceeds which their outputs are expected to yield;
and the effective demand is the point on the aggregate demand function
which becomes effective because, taken in conjunction with the
conditions of supply, it corresponds to the level of employment which
maximises the entrepreneur's expectation of profit.
さらに言うなら、「有効需要」とは、簡単にいえば、企業家が供給すると決めた当期の雇用量から自分が受け取ると予想する総所得（あるいは売上）のことであ
り、企業家が生産要素に渡すことになる所得も含まれている。総需要関数とは、様々に仮定した雇用量に、その雇用の産出物がもたらすと予想される売上を関連
付けるものである。したがって、有効需要とはその総需要関数上の点であり、その点が「有効」と言えるのは、供給条件と組み合わされることによって、その点
が企業家の利潤の予想値を最大化する雇用レベルを指すからである。
This set of definitions also has the advantage that we can equate the
marginal proceeds (or income) to the marginal factor cost; and thus
arrive at the same sort of propositions relating marginal proceeds thus
defined to marginal factor costs as（= the same ...as ） have been stated
by those economists who, by ignoring user cost or assuming it to be
zero, have equated supply price[3] to marginal factor cost.[4]
我々はこの一連の定義のおかげで、限界売上（あるいは限界所得）を限界要素費用と等値出来るようになる。つまり我々は、上記で定義された売上（＝使用費用
を含まない）の限界値を要素費用の限界値に関連付けることで、これまでの経済学者が使用費用を無視するかゼロと見なして供給価格[３]を限界要素費用に等
値させて来たのと同種の主張に到達することが出来るのである[４]。
(ii) We turn, next, to the second of the principles referred to above.
We have dealt so far with that part of the change in the value of the
capital equipment at the end of the period as compared with its value
at the beginning which is due to the voluntary decisions of the
entrepreneur in seeking to maximise his profit. But there may, in
addition, be an involuntary loss (or gain) in the value of his capital
equipment, occurring for reasons beyond his control and irrespective of
his current decisions, on account of (e.g.) a change in market values,
wastage by obsolescence or the mere passage of time, or destruction by
catastrophe such as war or earthquake.
（ｉｉ）次に、上で言及した二番目の方法に移ろう。これまで我々は期間の最初と最後での資本設備の価値の変化を扱ってきた。その変化は利潤を最大にしよう
とする企業家の意図的な決定によってもたらされるものであった。しかし、その他に、資本設備の価値に関しては意図せず損（あるいは得）をすることがあり、
それは当期の決定とは無関係にどうすることも出来ない理由で起こる。つまり、市場価格の変動、旧式化による損失、単なる時間の経過、戦争や地震などの災難
による破壊である。
Now some part of these involuntary losses, whilst they are unavoidable,
are ― broadly speaking ― not unexpected; such as losses through the
lapse of time irrespective of use, and also “normal” obsolescence
which, as Professor Pigou expresses it, “is sufficiently regular to be
foreseen, if not in detail, at least in the large”, including, we may
add, those losses to the community as a whole which are sufficiently
regular to be commonly regarded as “insurable risks”. Let us ignore for
the moment the fact that the amount of the expected loss depends on
when the expectation is assumed to be framed, and let us call the
depreciation of the equipment, which is involuntary but not unexpected,
i.e. the excess of the expected depreciation over the user cost, the
supplementary cost, which will be written V. It is, perhaps, hardly
necessary to point out that this definition is not the same as
Marshall's definition of supplementary cost, though the underlying
idea, namely, of dealing with that part of the expected depreciation
which does not enter into prime-cost, is similar.
ところで、これらの意図しない損失のある部分は、確かに避け難いものではあるがたいていは予期せぬものではない。それは例えば、使用度合いに関わらず時間
の経過によって進む損失や「通常の」旧式化である。それはピグー教授の言うように「充分規則的なもので」「詳細を見通せなくても大体は予想のつくものであ
り」、さらには普通「保険可能リスク」と見なされるような充分規則的な社会全体の損失が含まれる。しばらく、予期された損失の量が予想形成の時期に依存す
るという事実を無視することにしよう。そして不本意ではあるが予期せぬものではない設備の減価（それは予想される減価が「使用費用」（Ｕ）を超える分であ
るが）を「補足費用（＝補足的費用＝固定的減価償却）」と呼んでＶで表わすことにしよう。おそらくこの定義がマーシャルの「補足費用」の定義と異なるのは
指摘するまでもない。もっとも、その基礎となる考え方、つまり予想された減価償却のうち主要費用には含まれないもの（＝固定的減価償却費、使用しない設備
の減価）を扱うという考え方は似ていると言える。
In reckoning, therefore, the net income and the net profit of
the entrepreneur it is usual to deduct the estimated amount of the
supplementary cost from his income and gross profit as defined above.
For the psychological effect on the entrepreneur, when he is
considering what he is free to spend and to save, of the supplementary
cost is virtually the same as though it came off his gross profit. In
his capacity as a producer deciding whether or not to use the
equipment, prime-cost and gross profit, as defined above, are the
significant concepts. But in his capacity as a consumer the amount of
the supplementary cost works on his mind in the same way as if it were
a part of the prime-cost. Hence we shall not only come nearest to
common usage but will also arrive at a concept which is relevant to the
amount of consumption, if, in defining aggregate net income, we deduct
the supplementary cost as well as the user cost, so that aggregate net
income is equal to A - U - V.
したがって、企業家の「純所得」と「純利潤」を計算するときには、上記で定義された所得（＝Ａ－Ｕ）と粗利潤（＝Ａ－Ｕ－Ｆ）から推定の補足費用を差し引
くのが普通である。というのは、企業家が支出したり貯蓄したりできる額を考えるときには、補足費用は心理的にはその分だけ粗利潤から引かれているのと同じ
ことだからである。企業家が「生産者」の立場に立って資本設備を使用するかどうかを決めるときには、上記で定義した主要費用（＝Ｕ＋Ｆ）と粗利潤が重要な
ものとなる。しかし、企業家が「消費者」の立場に立つ場合には、補足費用（＝Ｖ
、固定的減価償却費）は主要費用の一部であるとする気持ちになる。だから、我々は慣用に出来るだけ近づくだけでなく、消費額を決定する一つの概念（＝純所
得）に到達するためには、「純所得」の総額を定義するときに、売上から使用費用（＝∪、原材料費＋可変的減価償却費）だけでなく補足費用（＝Ｖ
、固定的減価償却）も差し引かねばならないのである。つまり「純所得」の総額はＡ－Ｕ－Ｖに等しくなるのである。
There remains the change in the value of the equipment, due to
unforeseen changes in market values, exceptional obsolescence or
destruction by catastrophe, which is both involuntary and ― in a broad
sense ― unforeseen. The actual loss under this head, which we disregard
even in reckoning net income and charge to capital account, may be
called the windfall loss.
設備の価値の変化のうちで最後に残るものは、予期せぬ市場価格の変化、例外的な旧式化、災害による破壊である。最後のものは不本意な変化であると同時に広
い意味で予期せぬ変化である。この項目に入る実際の損失は「純所得」の計算には含めずに「資本勘定（＝資本収支）」で扱うものであり「偶発的損失（＝意外
の損失）」と呼ばれるのが相応しい。
The causal significance of net income lies in the psychological
influence of the magnitude of V on the amount of current consumption,
since net income is what we suppose the ordinary man to reckon his
available income to be when he is deciding how much to spend on current
consumption. This is not, of course, the only factor of which he takes
account when he is deciding how much to spend. It makes a considerable
difference, for example, how much windfall gain or loss he is making on
capital account. But there is a difference between the supplementary
cost and a windfall loss in that changes in the former are apt to
affect him in just the same way as changes in his gross profit. It is
the excess of the proceeds of the current output over the sum of the
prime-cost and the supplementary cost which is relevant to the
entrepreneur's consumption; whereas, although the windfall loss (or
gain) enters into his decisions, it does not enter into them on the
same scale ― a given windfall loss does not have the same effect as an
equal supplementary cost.
経済的要因としての純所得の意味は、Ｖ（＝補足費用）の大きさが当期の消費額の大きさに与える心理的影響にある。「純所得」とは一般の人の場合なら当期の
消費にどれだけ支出できるかを決めるときに自由にできると見做す額であるからである。もちろん、これだけが支出を決めるときに考慮する唯一の要素ではな
い。例えば、企業家が資本勘定にどれだけ偶発的な損得を含めるかによって非常に大きな違いがうまれる。しかし、補足費用と偶発的損失の間には大きな違いが
ある。補足費用の変化は粗利潤の変化と同じような影響を企業家に与えるからである。そして、企業家の消費にとって重要なのは、当期の産出物から生まれた売
上から主要費用と補足費用の合計を差し引いた額なのである。それに対して、偶発的損失（あるいは利潤）は企業家の決定に影響するものの、補足費用と同じよ
うに影響することはない。偶発的な損失は同額の補足費用と同じ影響力を持たないのである。
We must now recur, however, to the point that the line between
supplementary costs and windfall losses, i.e. between those unavoidable
losses which we think it proper to debit to income account and those
which it is reasonable to reckon as a windfall loss (or gain) on
capital account, is partly a conventional or psychological one,
depending on what are the commonly accepted criteria for estimating the
former. For no unique principle can be established for the estimation
of supplementary cost, and its amount will depend on our choice of an
accounting method. The expected value of the supplementary cost, when
the equipment was originally produced, is a definite quantity. But if
it is re-estimated subsequently, its amount over the remainder of the
life of the equipment may have changed as a result of a change in the
meantime in our expectations; the windfall capital loss being the
discounted value（＝減価、割引価値、現在価値、将来含まれる利息を割り引いた値） of the difference
between the former and the revised expectation of the prospective
series of U + V.
しかしながら、我々は次の点に立ち戻らねばならない。即ち、補足費用と偶発的損失との間の線引き、つまり、所得勘定の借り方につけるのが相応しいと思われ
る避け難い損失と、資本勘定に偶発的損失（あるいは利潤）として計上すべきものとの間の線引きは、慣習的であるか心理的なものであって、一般に行われてい
る補足費用の算定基準に依存しているのである。というのは、補足費用を算定する方法を一つに設定することは不可能なので、補足費用の額は会計のやり方次第
で違ってくるからである。また、設備が最初に作られた時に予想された補足費用の額は明確であるが、その後、その額が計算し直されると、設備の残りの寿命の
期間についての補足費用の額は、それまでの期間の我々の予想の変化によって、変わってしまう可能性がある。それに対して、資本の偶発的損失は、予想される
Ｕ＋Ｖの組み合わせの最初の予想額と変更された予想額との差額の割引価値（＝現在価値、将来の価値を利率分割り引いた現在の値）である。
It is a widely approved principle of business accounting,
endorsed by the Inland Revenue authorities, to establish a figure for
the sum of the supplementary cost and the user cost when the equipment
is acquired and to maintain this unaltered during the life of the
equipment, irrespective of subsequent changes in expectation. In this
case the supplementary cost over any period must be taken as the excess
of this predetermined figure over the actual user cost. This has the
advantage of ensuring that the windfall gain or loss shall be zero over
the life of the equipment taken as a whole. But it is also reasonable
in certain circumstances to recalculate the allowance for supplementary
cost on the basis of current values and expectations at an arbitrary
accounting interval, e.g. annually. Business men in fact differ as to
which course they adopt. It may be convenient to call the initial
expectation of supplementary cost when the equipment is first acquired
the basic supplementary cost, and the same quantity recalculated up to
date on the basis of current values and expectations the current
supplementary cost.
一つ広く認められた企業会計の方法がある。英国の内国歳入庁の権威筋によって認められている方法で、それは設備を入手した時に使用費用と補足費用の合計
（＝Ｕ＋Ｖ）を設定して、その後の予想の変化に関わらず、設備の寿命が続く限りこの数字を変更しないという方法である。この場合には、どの期間に対する補
足費用（＝Ｖ）も、あらかじめ決められたこの数字から実際の使用費用（＝Ｕ）を差し引いた残りと見なされなければならない。こうすれば設備の寿命の期間を
通じて偶発的な損得（Ｕ＋Ｖの変化）をゼロに保てるという利点がある。しかし、ある環境においては、補足費用に対する引当金を任意の間隔を置いて（つまり
１年毎に）現在の価値と予想に基づいて計算し直すほうが合理的である。実業家が実際どの方法を採用するかは様々である。設備を最初に入手したときの補足費
用の初めの予測を「基本的補足費用」と呼び、現在の価値と予測に基づいて再計算した値を「当期補足費用」と呼ぶのが便利かもしれない。
Thus we cannot get closer to a quantitative definition of supplementary
cost than that it comprises those deductions from his income which a
typical entrepreneur makes before reckoning what he considers his net
income for the purpose of declaring a dividend (in the case of a
corporation) or of deciding the scale of his current consumption (in
the case of an individual). Since windfall charges（=changesの誤植かも。以後は
windfall changesとなっている） on capital account are not going to be ruled
out of the picture, it is clearly better, in case of doubt, to assign
an item to capital account, and to include in supplementary cost only
what rather obviously belongs there. For any overloading of the former
can be corrected by allowing it more influence on the rate of current
consumption than it would otherwise have had.
つまり、補足費用の量的な定義に関しては、（企業の場合には）配当金を公表する目的で（個人の場合には）当期の消費額を決定する目的で、企業家が自分の純
所得（＝Ａ－Ｕ－Ｖ）を計算する前に所得（＝Ａ－Ｕ）から控除する額は補足費用に含まれるということ以上に詳しい定義はできないのである。偶発的変化は資
本勘定で扱うことがやめられない以上、疑わしい項目は資本勘定に回して、補足費用の中身はそこに含まれることが明白なものだけにするが望ましい。というの
は、資本勘定に含める項目が多くなりすぎても、資本勘定が増えたことで普段よりも当期の消費高が影響を受けるだけだからである。
It will be seen that our definition of net income comes very
close to Marshall's definition of income, when he decided to take
refuge in the practices of the Income Tax Commissioners and ― broadly
speaking ― to regard as income whatever they, with their experience,
choose to treat as such. For the fabric of their decisions can be
regarded as the result of the most careful and extensive investigation
which is available, to interpret what, in practice, it is usual to
treat as net income. It also corresponds to the money-value of
Professor Pigou's most recent definition of the National Dividend.[5]
我々の純所得の定義がマーシャルの所得の定義と非常によく似ていることはすぐに分かるだろう。簡単に言うと、彼は所得税徴税官の習慣を使って、徴税官が自
分の経験から所得と見做すものは全て所得と見做すことにしたのである。徴税官の決め方は最も慎重かつ広範な調査にもとづくものであり、それはふつう純所得
として扱われるべきものが何であるかを理解するのに格好の調査である。我々の定義はまたピグー教授が最近定義した「国民分配分」の貨幣価値と符合する。
It remains true, however, that net income, being based on an
equivocal criterion which different authorities might interpret
differently, is not perfectly clear-cut. Professor Hayek, for example,
has suggested that an individual owner of capital goods might aim at
keeping the income he derives from his possession constant, so that he
would not feel himself free to spend his income on consumption until he
had set aside sufficient to offset any tendency of his
investment-income to decline for whatever reason.[6] I doubt if such an
individual exists; but, obviously, no theoretical objection can be
raised against this deduction as providing a possible psychological
criterion of net income. But when Professor Hayek infers that the
concepts of saving and investment suffer from a corresponding
vagueness, he is only right if he means net saving and net investment.
The saving and the investment, which are relevant to the theory of
employment, are clear of this defect, and are capable of objective
definition, as we have shown above.
もっとも、純所得は学者によっては解釈の異なる曖昧な基準にもとづいているので、完全に明確なものにならないのは仕方がない。例えば、ハイエク教授の考え
では、資本財の所有者は自分の財産から得られる所得を一定にすることを目指しているので、投資所得が減らないように貯えを充分にするまでは所得を消費にど
んどん回す気にはならないらしい[６]。私にはそんな人が実際にいるとは思えないが、純所得の心理学的な基準をもたらすこの償却費を論理的に否定すること
はできないのだ。しかし、ハイエク教授が、貯蓄と投資の概念にもこれと同じ曖昧さがあると言っていることについては、それが「純貯蓄」と「純投資」を意味
するのでなければ、彼は間違っている。雇用理論にとって重要な意味を持つ「貯蓄」と「投資」には曖昧さは存在しないし、上で示したように客観的な定義が可
能なのである。
Thus it is a mistake to put all the emphasis on net income,
which is only relevant to decisions concerning consumption, and is,
moreover, only separated from various other factors affecting
consumption by a narrow line; and to overlook (as has been usual) the
concept of income proper, which is the concept relevant to decisions
concerning current production and is quite unambiguous.
つまり、「純所得」ばかりを強調して本来の所得の概念を（よくあるように）無視するのは間違いである。純所得は消費の決定にしか関わらないものであり、消
費に影響する他の様々な要素と大きな違いはない。むしろ当期の生産の決定に関わる概念である本来の「所得」には全く曖昧なところがないのである。
The above definitions of income and of net income are intended
to conform as closely as possible to common usage. It is necessary,
therefore, that I should at once remind the reader that in my Treatise
on Money I defined income in a special sense. The peculiarity in my
former definition related to that part of aggregate income which
accrues to the entrepreneurs, since I took neither the profit (whether
gross or net) actually realised（利益を得る） from their current operations
nor the profit which they expected when they decided to undertake their
current operations, but in some sense (not, as I now think,
sufficiently defined if we allow for the possibility of changes in the
scale of output) a normal or equilibrium profit; with the result that
on this definition saving exceeded investment by the amount of the
excess of normal profit over the actual profit.
上記の所得と純所得の定義は出来るだけ慣用に合わせることを目指している。だから、読者には『貨幣論』のなかで私が行った所得の定義が特殊なものだったこ
とを思い出してもらう必要がある。以前の私の特殊な定義は、総所得のうちで企業家が手にする部分だけについてのものだったからである。というのは私が取り
上げたのは、現在の事業から実際に実現された利潤（純利潤にしろ粗利潤にしろ）でもなく、現在の事業を行う決定をしたときに予想した利潤でもなく、いわば
正常利潤（＝「通常利潤」「正常報酬」）あるいは均衡利潤（これはいま考えると産出量の変化の可能性を含めた充分な定義にはなっていなかった）だったから
である。その結果、この定義では、正常利潤が実利潤を上回る分だけ貯蓄が投資を上回ることになっていた。
I am afraid that this use of terms has caused considerable
confusion, especially in the case of the correlative use of saving;
since conclusions (relating, in particular, to the excess of saving
over investment), which were only valid if the terms employed were
interpreted in my special sense, have been frequently adopted in
popular discussion as though the terms were being employed in their
more familiar sense. For this reason, and also because I no longer
require my former terms to express my ideas accurately, I have decided
to discard them ― with much regret for the confusion which they have
caused.
この用語の使い方は、特に貯蓄について使用される場合には、かなり混乱を引き起こしたのではないかと思う。というのは、あそこでの様々な結論（特に貯蓄が
投資を上回る分に関する結論）は、私が使った専門用語を私だけの特別な意味で解釈して初めて意味があるのに、それがまるで一般的な意味で使われているかの
ように、多くの議論の中に引用されたからである。そのために、私はそれらの用語を使うのを止めることにした。また、私の考えを正確に表わすのに以前の用語
を使う必要はなくなっている。それらの用語が引き起こした混乱を私は非常に後悔している。
II. Saving and Investment
Amidst the welter（混乱） of divergent（異なる） usages of terms, it is
agreeable to discover one fixed point. So far as I know, everyone is
agreed that saving means the excess of income over expenditure on
consumption. Thus any doubts about the meaning of saving must arise
from doubts about the meaning either of income or of consumption.
Income we have defined above. Expenditure on consumption during any
period must mean the value of goods sold to consumers during that
period, which throws us back to the question of what is meant by a
consumer-purchaser. Any reasonable definition of the line between
consumer-purchasers and investor-purchasers will serve us equally well,
provided that it is consistently applied. Such problem as there is,
e.g. whether it is right to regard the purchase of a motor-car as a
consumer-purchase and the purchase of a house as an investor-purchase,
has been frequently discussed and I have nothing material to add to the
discussion.
第２節 貯蓄と投資
専門用語の様々な用法が混乱している中に一つ不動な点を発見するのは気持のいいことである。私の知る限り、「貯蓄」が所得から消費支出を差し引いたものを
意味することは誰も異論のないところである。つまり、「貯蓄」の意味に疑いが生まれるとすれば、それは必ず「所得」か「消費」の意味に対する疑問からであ
る。我々は「所得」については上で定義した。確かに、ある期間における消費支出とはその期間に消費者に販売された財の価格を意味している。しかし、この定
義は我々を消費者としての買い手とは何を意味するかという問題に引き戻す。消費者としての買い手と投資者としての買い手を区別する線引きの定義がもし合理
的で一貫して適用されるものなら、充分我々に役立ってくれる。このような問題、例えば、自動車を買うことは消費者が買うと見做すべきか、家を買うことは投
資家が買うと見做すべきかという問題は、しばしば議論の対象になってきたが、この議論に対して付け加える材料は私にはない。
The criterion must obviously correspond to where we draw the line
between the consumer and the entrepreneur. Thus when we have defined A1
as the value of what one entrepreneur has purchased from another, we
have implicitly settled the question. It follows that expenditure on
consumption can be unambiguously defined as Σ(A - A1), where ΣA is the
total sales made during the period and ΣA1 is the total sales made by
one entrepreneur to another. In what follows it will be convenient, as
a rule, to omit Σ and write A for the aggregate sales of all kinds, A1
for the aggregate sales from one entrepreneur to another and U for the
aggregate user costs of the entrepreneurs.
この判断基準は明らかに消費者と企業家の間の線引きと一致しなければならない。つまり、企業家が他の企業家から購入した物の価格をＡ１と定義したとき、我
々は暗黙裡にこの問題に決着を付けたことになる。そこから、消費支出はΣ（Ａ－Ａ１）と明確に定義できるのである。ここでΣＡはその期間内に行われた全販
売であり、ΣＡ１は企業家が別の企業家に対して行った全購入を意味する。以下においては便宜のために、概してあらゆる種類の販売の総額はΣを省略してＡと
書き、企業家から別の企業家への販売の総額をＡ１と書き、企業家の使用費用の総額をＵと書くことにする。
Having now defined both income and consumption, the definition
of saving, which is the excess of income over consumption, naturally
follows. Since income is equal to A - U and consumption is equal to A -
A1, it follows that saving is equal to A1 - U. Similarly, we have net
saving for the excess of net income over consumption, equal to A1 - U -
V.
既に「所得」と「消費」の両方を定義しおえたからには、所得から消費を引いた余りである「貯蓄」の定義は当然次のようになる。所得はＡ－Ｕと等しく、消費
はＡ－Ａ１に等しいから、ここから貯蓄はＡ１－Ｕと等しいことになる。同様にして、「純所得」（＝Ａ－Ｕ－Ｖ）から消費（＝Ａ－Ａ１）を差し引いた「純貯
蓄」は、Ａ１－Ｕ－Ｖに等しくなる。
Our definition of income also leads at once to the definition of
current investment. For we must mean by this the current addition to
the value of the capital equipment which has resulted from the
productive activity of the period. This is, clearly, equal to what we
have just defined as saving. For it is that part of the income of the
period which has not passed into consumption. We have seen above that
as the result of the production of any period entrepreneurs end up with
（１）having sold finished output having a value A and with （２）a capital
equipment which has suffered a deterioration measured by U (or an
improvement measured by -U where U is negative) as a result of having
produced and parted with A,after allowing for（＝訳さない） purchases A1 from
other entrepreneurs.
また、我々の所得の定義からはただちに当期の投資の定義を導くことが出来る。というのは、「当期の投資」とは資本設備の価値への追加を意味する以外にない
からである。そしてその追加はこの期間の生産活動の結果なのである。これは明らかに我々が今しがた貯蓄と定義したものと等しい。というのは、それはこの期
間の所得のうちで消費に回されなかったものだからである。我々が上で見たように、ある期間の生産を終えた企業家は最後には、価値がＡの完成産出物を販売し
ており、価値がＵだけ減少（あるいはＵがマイナスのときは－Ｕだけ改善）した資本設備をもっている。この減価は他の企業家からのＡ１の購入後に産出物Ａを
生産して手放した結果である。
During the same period finished output having a value A - A1 will have
passed into consumption. The excess of A - U over A - A1, namely A1 -
U, is the addition to capital equipment as a result of the productive
activities of the period and is, therefore, the investment of the
period. Similarly A1 - U - V, which is the net addition to capital
equipment, after allowing for normal impairment in the value of capital
（１）apart from（＝単なるfromと同じ） its being used and （２）apart from windfall
changes in the value of the equipment chargeable to capital account, is
the net investment of the period.
これと同じ期間の間にＡ－Ａ１の価値を持つ完成産出物が消費に移される。Ａ－Ｕ（＝所得）がＡ－Ａ１（＝消費）上回る分、即ちＡ１－Ｕ（＝貯蓄）が、その
期間の生産活動の結果としての資本設備への追加であり、それゆえこの期間の投資となる。同様にして、Ａ１－Ｕ－Ｖ（＝純貯蓄）、即ち資本設備に対する純追
加がその期間の「純投資」である。この場合、資本勘定に計上される設備価値の偶発的変化による減価（＝Ｖ）と、使用による資本価値の通常の減価（＝Ｕ）が
考慮されているのである。
Whilst, therefore, the amount of saving is an outcome of the collective
behaviour of individual consumers and the amount of investment of the
collective behaviour of individual entrepreneurs, these two amounts are
necessarily equal, since each of them is equal to the excess of income
over consumption. Moreover, this conclusion in no way depends on any
subtleties or peculiarities in the definition of income given above.
Provided it is agreed that income is equal to the value of current
output, that current investment is equal to the value of that part of
current output which is not consumed, and that saving is equal to the
excess of income over consumption ― all of which is conformable both to
common sense and to the traditional usage of the great majority of
economists ― the equality of saving and investment necessarily follows.
したがって、貯蓄量は個々の消費者の集団的行動の結果であり、投資量は個々の企業家の集団的行動の結果であるにも関わらず、この二つの額は必然的に一致す
る。というのは、そのどちらもが所得が消費を上回る額だからである。さらに、この結論は決して上記の所得の定義の細かい点や独自な点に左右されることはな
い。所得は当期の産出物の価格に等しく、投資は当期の産出物のうちで消費されない部分に等しく、貯蓄は所得が消費を上回る額に等しいことを認める限り（こ
れらは全て常識とも大多数の経済学者の伝統的用法とも一致している）、貯蓄と投資が等しいことは必然的結果である。
In short―
Income = value of output = consumption + investment.
Saving = income - consumption.
Therefore saving = investment.
要するに、
所得＝産出物の価格＝消費＋投資であり、
貯蓄＝所得－消費である。
故に、貯蓄＝投資である。
Thus any set of definitions which satisfy the above conditions leads to
the same conclusion. It is only by denying the validity of one or other
of them that the conclusion can be avoided.
つまり、どのような定義を採用しようと、上記の等式を満たす限り同じ結論に至るのである。
この結論を避けるには、これらの定義のどれかの有効性を否定するしかない。
The equivalence between the quantity of saving and the quantity of
investment emerges from the bilateral character of the transactions
between the producer on the one hand and, on the other hand, the
consumer or the purchaser of capital equipment.
貯蓄量と投資量が等しいことは、一方における生産者と他方における消費者あるいは資本設備の買い手との間の取り引きが双方向的性格をもっていることから来ている。
Income is created by the value in excess of user cost which the
producer obtains for the output he has sold; but the whole of this
output must obviously have been sold either to a consumer or to another
entrepreneur; and each entrepreneur's current investment is equal to
the excess of the equipment which he has purchased from other
entrepreneurs over his own user cost. Hence, in the aggregate the
excess of income over consumption, which we call saving, cannot differ
from the addition to capital equipment which we call investment. And
similarly with net saving and net investment. Saving, in fact, is a
mere residual. The decisions to consume and the decisions to invest
between them determine incomes. Assuming that the decisions to invest
become effective, they must in doing so either curtail consumption or
expand income. Thus the act of investment in itself cannot help causing
the residual or margin, which we call saving, to increase by a
corresponding amount.
所得は生産者が産出物を売って得た価格から使用費用を引いたものである。しかし、この産出物がすべて消費者か他の企業家に売られたものであるのは明らかで
ある。そして、それぞれの企業家の当期の投資は、他の企業家から購入した設備から自分の使用費用を引いた額である。すると、総額において、所得から消費を
引いた分、つまり我々が貯蓄と呼ぶことのできるものは、資本設備への追加、つまり我々が投資と呼ぶことのできるものと同じ額にならざるを得ない。事実、貯
蓄は単なる余剰である。消費をする決断と投資をする決断が一緒になって所得を決めるのである。投資の決断が実行されるとすると、それは消費を切り詰めるか
所得を拡大しなければなららない。つまり、投資という行為はそれ自体で、余剰あるいは差額を同じ量だけ増やすことにならざるをえないのである。その余剰を
我々は貯蓄と呼ぶのである。
It might be, of course, that individuals were so te^te monte'e
in their decisions as to how much they themselves would save and invest
respectively, that there would be no point of price equilibrium at
which transactions could take place. In this case our terms would cease
to be applicable, since output would no longer have a definite market
value, prices would find no resting-place between zero and infinity.
Experience shows, however, that this, in fact, is not so; and that
there are habits of psychological response which allow of an
equilibrium being reached at which the readiness to buy is equal to the
readiness to sell. That there should be such a thing as a market value
for output is, at the same time, a necessary condition for money-income
to possess a definite value and a sufficient condition for the
aggregate amount which saving individuals decide to save to be equal to
the aggregate amount which investing individuals decide to invest.
もちろん、個々の人間がどれだけ貯蓄し投資するかをそれぞれ決めるときに頭に血が登って、取り引きが価格の均衡をもたらさないことは考えられる。この場合
には、我々の用語は適用できなくなる。というのは、産出物はもはや明確な市場価格を持たなくなり、価格はゼロから無限大の間をさまようことになるからであ
る。しかし、経験から実際にはこんなことは起こらないことを我々は知っている。むしろ、心理的な反応がいつも起こって、売りたい気持と買いたい気持が一致
する均衡点に到達するようになっているのである。産出物に対する市場価格というものが存在するということは、名目所得が明確な値をもつための必要条件であ
るだけでなく、貯蓄する個々人が貯蓄しようとする総額と、投資する個々人が投資しようとする総額が等しくなるための十分条件でもあるのである。
Clearness of mind on this matter is best reached, perhaps, by thinking
in terms of decisions to consume (or to refrain from consuming) rather
than of decisions to save. A decision to consume or not to consume
truly lies within the power of the individual; so does a decision to
invest or not to invest. The amounts of aggregate income and of
aggregate saving are the results of the free choices of individuals
whether or not to consume and whether or not to invest; but they are
neither of them capable of assuming an independent value resulting from
a separate set of decisions taken irrespective of the decisions
concerning consumption and investment. In accordance with this
principle, the conception of the propensity to consume will, in what
follows, take the place of the propensity or disposition to save.
この問題で頭をすっきりさせる一番よい方法は、恐らくは貯蓄する決断について考えるよりも消費するかしないの決断について考えることである。消費をするか
しないを決めることはまさに個人の力で出来ることである。投資するしないの決断も同様である。総所得と総貯蓄の額は、消費と投資に関する個人の自由な選択
の結果である。しかしながら、総所得と総貯蓄の額がそれぞれ独自の値を持つことはない。つまり、総所得と総貯蓄の額は、消費と投資に関する決断とは無関係
に行われた個別の決断の結果であることはないのである。この原則にしたがって、以下においては、消費性向の概念が貯蓄性向や貯蓄傾向の代わりをすることに
なる。
Author's Footnotes
[1]. Some further observations on user cost are given in an appendix to this chapter.
[2]. As distinguished from his net income which we shall define below.
[3]. Supply price is, I think, an incompletely defined term, if the
problem of defining user cost has been ignored. The matter is further
discussed in the appendix to this chapter, where I argue that the
exclusion of user cost from supply price, whilst sometimes appropriate
in the case of aggregate supply price, is inappropriate to the problems
of the supply price of a unit of output for an individual firm.
[4]. For example, let us take Zw = φ(N), or alternatively Z = W.
φ(N)（＝ピリオドは掛け算を表す） as the aggregate supply function (where W is the
wage-unit and W.Zw = Z). Then, since the proceeds of the marginal
product is equal to the marginal factor-cost at every point on the
aggregate supply curve, we have
ΔN = ΔAw - ΔUw = ΔZw = Δφ(N),
that is to say φ'(N) = 1; provided that factor cost bears a constant
ratio to wage-cost, and that the aggregate supply function for each
firm (the number of which is assumed to be constant) is independent of
the number of men employed in other industries, so that the terms of
the above equation, which hold good for each individual entrepreneur,
can be summed for the entrepreneurs as a whole. This means that, if
wages are constant and other factor costs are a constant proportion of
the wages-bill, the aggregate supply function is linear with a slope
given by the reciprocal of the money-wage.
[5]. Economic Journal, June 1935, p. 235.
[6]. “The Maintenance of Capital”, Economica, August 1935, p. 241 et seq.
著者注
[１] 使用費用についてのさらなる若干の考察がこの章の付録で行われている。
[２] それに対する「純所得」については後で定義するだろう。
[３]
「供給価格」は、使用費用を定義する問題が無視されている限り、充分に定義された用語とは言えないと思われる。この問題はこの章の付録で詳しく議論され
る。そこで私は、供給価格から使用費用を除外するのは、総供給価格の場合に適切なことであるが、個別の企業に対する産出物１単位の供給価格を問題にすると
きには適切ではないと主張している。
[４]
例として、総供給関数としてＺｗ＝φ（Ｎ）あるいはＺ＝Ｗ・φ（Ｎ）を考える（ここでＷは単位賃金でありＷ・Ｚｗ＝Ｚである）（Ｚｗ＝Ｚ／Ｗ＝労働時
間）。すると、限界生産の売上は、総供給曲線のあらゆる点で、限界要素費用と等しくなる（→ΔＡ－ΔＵ＝Ｗ・ΔＮ）ので、
ΔＮ＝ΔＡｗ－ΔＵｗ＝ΔＺｗ＝Δφ（Ｎ）（＝Ｚは使用費用を含まない売上）
が成立する。すなわち、φ’（Ｎ）＝１である（←Δφ（Ｎ）＝ΔＮからｄφ（Ｎ）／ｄＮ＝ｄＮ／ｄＮ＝１）。但し、要素費用と賃金費用（＝初出）の比率は
一定とし、それぞれの企業の総供給関数は他の産業での雇用人数から独立であるため、この等式の各項は個々の企業にとって有効であるだけでなく、それぞれの
総計は企業全体にとって有効なものとする。これは、賃金が一定で、他の要素費用と総賃金費用の比率も一定の場合には、総供給関数は直線となり、その勾配は
名目賃金の逆数によって与えられる（＝名目賃金に反比例する）ことを意味する。（＝『コンメンタール』ｐ１２３以下では、この注は難解である上に間違って
いると言われている。）
[５] 『エコノミック・ジャーナル』（1935年7月235頁）
[６] 「資本の維持」（『エコノミカ』1935年8月241頁以下）
Appendix on User Cost
付録、使用費用について
I
USER cost has, I think, an importance for the classical theory
of value which has been overlooked. There is more to be said about it
than would be relevant or appropriate in this place. But, as a
digression, we will examine it somewhat further in this appendix.
第１節
使用費用はこれまで見落とされてきたが古典派の価格理論にとって重要なものだと思われる。使用費用については、所得の定義とは関係ないこともあるし、ここで語るにはふさわしくないが、脱線して、この付録で詳しく検討してみよう。
An entrepreneur's user cost is by definition equal to
A1 + (G' - B') - G,
where A1 is the amount of our entrepreneur's purchases from other
entrepreneurs, G the actual value of his capital equipment at the end
of the period, and G' the value it might have had at the end of the
period if he had refrained from using it and had spent the optimum sum
B' on its maintenance and improvement. Now G - (G' - B'), namely the
increment in the value of the entrepreneur's equipment beyond the net
value which he has inherited from the previous period, represents the
entrepreneur's current investment in his equipment and can be written
I. Thus U, the user cost of his sales-turnover A, is equal to A1 - I
where A1 is what he has bought from other entrepreneurs and I is what
he has currently invested in his own equipment. A little reflection
will show that all this is no more than common sense. Some part of his
outgoings to other entrepreneurs is balanced by the value of his
current investment in his own equipment, and the rest represents the
sacrifice which the output he has sold must have cost him over and
above the total sum which he has paid out to the factors of production.
企業家の使用費用は定義としては
Ａ１＋（Ｇ’－Ｂ’）－Ｇ （＝上記では（Ｇ’－Ｂ’）－（Ｇ－Ａ１））
と等しい。ここでＡ１は我らが企業家による他の企業家からの購入量（＝原材料費）であり、Ｇはこの期間の終りにおける彼の資本設備の実際の価値であり、
Ｇ’はもし設備を使わずに設備の維持改善に最適な額Ｂ’を支出していた場合に期間の終りに設備がもちえた価値である。さてＧ－（Ｇ’－Ｂ’）は企業家の設
備の価値（＝Ｇ）が前期から受け継いだ純価値（＝Ｇ’－Ｂ’）を上回る増加分で、企業家による設備に対する当期の投資を表しており、Ｉと書くことが出来
る。すると、販売売上Ａの使用費用ＵはＡ１－Ｉに等しい（Ｉ＝Ａ１－Ｕは既出）。ここでＡ１は他の企業家からの購入であり、Ｉは当期に自分の設備に行った
投資である。少し考えればこれが常識以外の何物でもないことはすぐに分かる。他の企業家への支出（＝Ａ１）の一部は自分の設備に対する当期の投資（＝－
I）で相殺されて、その残り（＝∪）は彼が売った産出物の製造にかかった経費のうちで生産要素へ支払った額を超える分（＝原材料費＋可変的減価償却費）を
表しているからである。
If the reader tries to express the substance of this otherwise,
he will find that its advantage lies in its avoidance of insoluble (and
unnecessary) accounting problems. There is, I think, no other way of
analysing the current proceeds of production unambiguously. If industry
is completely integrated or if the entrepreneur has bought nothing from
outside, so that A1 = 0, the user cost is simply the equivalent of the
current disinvestment involved in using the equipment; but we are still
left with the advantage that we do not require at any stage of the
analysis to allocate the factor cost between the goods which are sold
and the equipment which is retained. Thus we can regard the employment
given by a firm, whether integrated or individual, as depending on a
single consolidated decision ― a procedure which corresponds to the
actual interlocking character of the production of what is currently
sold with total production.
もしこれを読む人がこれと同じ事を別のやり方で表わそうとすれば、このやり方のお陰で会計上の解決不可能な（そして不必要な）問題に関わらずに済むことに
気づくだろう。私が思うに、当期の生産売上を曖昧さを残さずに分析する方法はこれ以外にないのである。もし産業が完全に統合されて企業家がよそからは何も
購入せず、その結果Ａ１＝０となる場合は、使用費用は単に設備の使用によって生じる当期のマイナス投資である。しかし、分析のどの段階でも、要素費用を販
売された製品と維持された設備の間に割り振る必要がないという利点は残る。つまり我々は、企業が統合されていようがいまいが、企業の与える雇用は一つの統
一された決定（＝使用費用を考えるやり方）によって行われると見ることが出来る。こうしたやり方こそ、当期に販売された物の生産が全生産過程（＝販売され
なかった物を含む）と実際に絡み合っているという性質とよく呼応しているのである。
The concept of user cost enables us, moreover, to give a clearer
definition than that usually adopted of the short-period supply price
of a unit of a firm's saleable output. For the short-period supply
price is the sum of the marginal factor cost and the marginal user cost.
さらに、使用費用の概念のおかげで、我々はある企業の販売可能な産出物１単位の短期供給価格に関して普通採用されている定義よりも明確な定義が得られる。というのは、短期供給価格は限界要素費用と限界使用費用の合計だからである。
Now in the modern theory of value it has been a usual practice
to equate the short-period supply price to the marginal factor cost
alone. It is obvious, however, that this is only legitimate if marginal
user cost is zero or if supply-price is specially defined so as to be
net of marginal user cost, just as I have defined (Chapter 3)
“proceeds” and “aggregate supply price” as being net of aggregate user
cost. But, whereas it may be occasionally convenient in dealing with
output as a whole to deduct user cost, this procedure deprives our
analysis of all reality if it is habitually (and tacitly) applied to
the output of a single industry or firm, since it divorces the “supply
price” of an article from any ordinary sense of its “price”; and some
confusion may have resulted from the practice of doing so. It seems to
have been assumed that “supply price” has an obvious meaning as applied
to a unit of the saleable output of an individual firm, and the matter
has not been deemed to require discussion.
ところで、現在の価格理論では短期供給価格は限界要素費用だけに等しいとするのが普通の習慣となっている。しかし、これが正しいのは、限界使用費用がゼロ
である場合か、供給価格を限界使用費用を含めずに特別に定義した場合だけであるのは明らかである。これは（第３章注３)「売上」と「総供給価格」を総使用
費用を含めず定義した私のやり方と同じである。時には全体としての産出物を使用費用を含めずに扱うのが便利かもしれないが、こんな事をもし習慣的に（そし
て暗黙に）単独の産業や企業の産出物に対して適用していると、我々の分析から現実味が全く失われてしまう。なぜなら、それによってある商品の「供給価格」
が普通の意味での「価格」から離れてしまうからである。また使用費用を含めない習慣から混乱さえ生まれてきたかもしれない。個々の企業の販売可能な単位産
出物に適用される「供給価格」の意味は明々白々だと思われてきたので、この問題を議論する必要はないと思われてきたのである。
Yet the treatment both of what is purchased from other firms and of the
wastage of the firm's own equipment as a consequence of producing the
marginal output involves the whole pack of perplexities which attend
the definition of income. For, even if we assume that the marginal cost
of purchases from other firms involved in selling an additional unit of
output has to be deducted from the sale-proceeds per unit in order to
give us what we mean by our firm's supply price, we still have to allow
for the marginal disinvestment in the firm's own equipment involved in
producing the marginal output. Even if all production is carried on by
a completely integrated firm, it is still illegitimate to suppose that
the marginal user cost is zero, i.e. that the marginal disinvestment in
equipment due to the production of the marginal output can generally be
neglected.
ところが、他企業から購入と、限界産出物を生産した結果としての企業設備の消耗の両方を扱うのは、所得を定義するのと同じくらい複雑なことなのである。と
いうのは、我々の意味する企業の供給価格を得るためには、産出物の追加１単位の販売に含まれる他企業からの購入の限界費用は、単位あたりの販売売上から差
し引かれねばならないと考えるとしても、それでもなお限界産出物の生産に含まれる企業の自己設備の限界マイナス投資（＝設備の消耗）を考慮に入れねばなら
ないからである。たとえ、完全に統合された企業ですべての生産が行われたとしても、限界使用費用をゼロとみなすこと、つまり限界産出物の生産による設備の
限界マイナス投資を無視できると考えることは間違っている。
The concepts of user cost and of supplementary cost also enable
us to establish a clearer relationship between long-period supply price
and short-period supply price. Long-period cost must obviously include
an amount to cover the basic supplementary cost as well as the expected
prime-cost appropriately averaged over the life of the equipment. That
is to say, the long-period cost of the output is equal to the expected
sum of the prime-cost and the supplementary cost; and, furthermore, in
order to yield a normal profit, the long-period supply price must
exceed the long-period cost thus calculated by an amount determined by
the current rate of interest on loans of comparable term and risk,
reckoned as a percentage of the cost of the equipment. Or if we prefer
to take a standard “pure”rate of interest, we must include in the
long-period cost a third term which we might call the risk-cost to
cover the unknown possibilities of the actual yield differing from the
expected yield.
使用費用と補足費用の概念によって、我々はまた長期供給価格と短期供給価格の関係を以前より明確にすることができる。長期費用には明らかに予想主要費用
（設備の寿命を通じて適宜平均化されている）と基本的な補足費用とをまかなう額が含まれねばならない。つまり、産出物の長期費用は、主要費用と補足費用の
合計の予想値に等しいのである。さらには、正常利潤を生み出すためには、長期供給価格は、このように計算された長期費用を上回らなければならない。こうし
て得られる正常利潤は、同種のリスクと満期（＝既出）を持つ現行の公債の利子率（＝リスク費用＋利子費用）次第で決まってくる。この利子率は設備の価格に
一定率をかけて計算されたものである。また、もし我々が標準的な「純粋利子率」（＝リスク費用を含む粗利子の対義語）を好むなら、長期費用にリスク費用を
第三項目として含めて、実際の収益が予想収益と異なるかもしれない事態に対処しなければならない。
Thus the long-period supply price is equal to the sum of the
prime-cost, the supplementary cost, the risk cost and the interest
cost, into which several components it can be analysed. The
short-period supply price, on the other hand, is equal to the marginal
prime-cost. The entrepreneur must, therefore, expect, when he buys or
constructs his equipment, to cover his supplementary cost, his risk
cost and his interest cost out of the excess of the marginal value of
the prime-cost over its average value; so that in long-period
equilibrium the excess of the marginal prime-cost over the average
prime-cost is equal to the sum of the supplementary, risk and interest
costs.[7]
つまり長期供給価格は主要費用と補足費用とリスク費用と利子費用の合計に等しい。長期供給価格はこれら複数の構成要素に分解できるのである。その一方で、
短期供給価格は限界主要費用（＝限界要素費用＋限界使用費用）に等しい。したがって、企業家は自分の設備を購入したり作ったりするときに、限界主要費用が
平均主要費用を上回る分によって補足費用とリスク費用と利子費用の合計がまかなえることを予想しなければならない。その結果、長期均衡状態においては、限
界主要費用が平均主要費用を上回る額が、補足費用とリスク費用と利子費用の合計に等しくなるのである[７]。
The level of output, at which marginal prime-cost is exactly
equal to the sum of the average prime and supplementary costs, has a
special importance, because it is the point at which the entrepreneur's
trading account breaks even. It corresponds, that is to say, to the
point of zero net profit; whilst with a smaller output than this he is
trading at a net loss. The extent to which the supplementary cost has
to be provided for apart from the prime-cost varies very much from one
type of equipment to another. Two extreme cases are the following:
限界主要費用が平均主要費用と補足費用の合計とちょうど等しくなる産出量のレベルは特に重要である。なぜなら、そこで企業家の売買勘定の均衡がとれるから
である。つまり、このレベルが純利潤がゼロになる点であり、これより少ない産出量では純損失になる。主要費用は別として、補足費用をどの程度準備すべきか
は設備のタイプによって大きく異なる。次にその極端に違う二つのケースをあげる。
(i) Some part of the maintenance of the equipment must
necessarily take place pari passu（par passus「等しい歩み」の奪格） with the act of
using it (e.g. oiling the machine). The expense of this (apart from
outside purchases) is included in the factor cost. If, for physical
reasons, the exact amount of the whole of the current depreciation has
necessarily to be made good in this way, the amount of the user cost
(apart from outside purchases) would be equal and opposite to that of
the supplementary cost; and in long-period equilibrium the marginal
factor cost would exceed the average factor cost by an amount equal to
the risk and interest cost.
（ｉ）設備の維持が必ず設備の使用と同時に行われなければならない（例えば機械に注油する）タイプ。この費用は（外部からの購入を別として）要素費用に含
まれる。物質的な理由から当期の減価の正確な額が必ず要素費用から補填される場合には、使用費用の額（外部からの購入を別に）は補足費用の額と等しくなっ
て、両者は相殺されてゼロになる。すると長期均衡状態においては、限界要素費用が平均要素費用を上回る額が、リスク費用と利子費用の合計と等しくなる（＝
使用費用も補足費用もなし）。
(ii) Some part of the deterioration in the value of the
equipment only occurs if it is used. The cost of this is charged in
user cost, in so far as it is not made good pari passu with the act of
using it. If loss in the value of the equipment could only occur in
this way, supplementary cost would be zero.
（ｉｉ）設備の価値の減少が、設備が使用された場合にのみ起こるタイプ。この費用は設備の使用と同時に補填されない場合には、使用費用に計上される。設備の価値の損失がこのようにしてのみ起こる場合には、補足費用はゼロとなる（＝補足費用だけなし）。
It may be worth pointing out that an entrepreneur does not use
his oldest and worst equipment first, merely because its user cost is
low; since its low user cost may be outweighed by its relative
inefficiency, i.e. by its high factor cost. Thus an entrepreneur uses
by preference that part of his equipment for which the user cost plus
factor cost is least per unit of output.[8] It follows that for any
given volume of output of the product in question there is a
corresponding user cost,[9] but that this total user cost does not bear
a uniform relation to the marginal user cost, i.e. to the increment of
user cost due to an increment in the rate of output.
ここで指摘しておくのがいいと思われる事は、企業家は単に使用費用が低いという理由で自分の設備の一番古い物や質の悪い物を最初に使うことはないというこ
とである。というのは、使用費用が低くても相対的に効率が悪くて要素費用が高くなっては意味がないからである。だから、企業家が好んで最初に使うのは自分
の設備のうちで、産出量１単位あたりの使用費用＋要素費用が最小のものである[８]。したがって、製品のどの産出量に対しても、それに相応しい使用費用と
いうものがある[９]。しかし、これを合計した使用費用は限界使用費用（産出量の増分に基づく使用費用の増分）と一定不変の関係にはないのである。
II
User cost constitutes one of the links between the present and
the future. For in deciding his scale of production an entrepreneur has
to exercise a choice between using up his equipment now and preserving
it to be used later on. It is the expected sacrifice of future benefit
involved in present use which determines the amount of the user cost,
and it is the marginal amount of this sacrifice which, together with
the marginal factor cost and the expectation of the marginal proceeds,
determines his scale of production. How, then, is the user cost of an
act of production calculated by the entrepreneur?
第２節
使用費用は現在と未来を結ぶ絆の一つである。というのは、生産規模を決めるときに企業家は自分の設備を使い切るか、それとも後でまた使うためにとっておく
かの選択を迫られる。使用費用の額を決めるのは現在の使用によって失われると予想される将来の利益なのである。この失われる利益の限界値（＝限界使用費
用）が限界要素費用と予想される限界売上といっしょになって企業家の生産規模を決める。では、一つの生産行為の使用費用を企業家はどうやって計算するの
か。
We have defined the user cost as the reduction in the value of
the equipment due to using it as compared with not using it, after
allowing for the cost of the maintenance and improvements which it
would be worth while to undertake and for purchases from other
entrepreneurs. It must be arrived at, therefore, by calculating the
discounted value（＝現在価値、次のpresent valueと同義） of the additional
prospective yield which would be obtained at some later date if it were
not used now. Now this must be at least equal to the present value of
the opportunity to postpone replacement which will result from laying
up the equipment; and it may be more.[10]
我々の定義では、使用費用とは、設備の適切な維持改善費用と他の企業家からの購入費に、設備を使わない場合に比べて設備を使った場合に減少する設備の価値
（＝減価償却費）を加えたものである。したがって、使用費用は、設備を今使わなければ将来余計に得られると予想される収益の割引価値（＝現在価値）を計算
することで求められねばならない。だから、設備を使わないでおけば設備の交換を延期できるが、そのことで得られる利益の現在価値が、最低限の使用費用とな
る。だから、それ以上である可能性がある[１０]。
If there is no surplus or redundant stock, so that more units of
similar equipment are being newly produced every year either as an
addition or in replacement, it is evident that marginal user cost will
be calculable by reference to the amount by which the life or
efficiency of the equipment will be shortened if it is used, and the
current replacement cost. If, however, there is redundant equipment,
then the user cost will also depend on the rate of interest and the
current (i.e. re-estimated) supplementary cost over the period of time
before the redundancy is expected to be absorbed through wastage, etc.
In this way interest cost and current supplementary cost enter
indirectly into the calculation of user cost.
もし余った在庫がなく、毎年同種の設備をあらたに増設したり交換したりしている場合には、設備を交換するのに現在必要な費用と、使用することで設備の寿命
や効率が低下する額を足せば限界使用費用が計算出来るのは明らかである。しかし、設備が余っている場合には、使用費用は、設備の余剰分が損耗などによって
吸収されるのが予想されるまでの期間の利子率と当期補足費用（再評価された）（＝既出）にも影響される。このようにして利子費用と当期補足費用は間接的に
使用費用の中に含まれるのである。
The calculation is exhibited in its simplest and most
intelligible form when the factor cost is zero. e.g. in the case of a
redundant stock of a raw material such as copper, on the lines which I
have worked out in my Treatise on Money, vol. ii. chap. 29. Let us take
the prospective values of copper at various future dates, a series
which will be governed by the rate at which redundancy is being
absorbed and gradually approaches the estimated normal cost. The
present value or user cost of a ton of surplus copper will then be
equal to the greatest of the values obtainable by subtracting from the
estimated future value at any given date of a ton of copper the
interest cost and the current supplementary cost on a ton of copper
between that date and the present.
この計算が最も簡単で分かりやすいのは要素費用がゼロの場合である。それは例えば、銅などの原材料の在庫が余っている場合であり、私が『貨幣論』の第２巻
２９章で扱ったやり方である。将来のさまざまな時点での銅の予想価格を考えてみると、その一連の価格を決めるのは銅の余剰分が吸収されて次第に推定される
標準価格に近づいていく早さである。つまり、余った１トンの銅の現在価値つまり使用費用は、１トンの銅の将来のある日の推定価格から、その日と現在の間に
生じる利子費用と当期補足費用を差し引いて得られる最大値と等しくなるだろう。
In the same way the user cost of a ship or factory or machine,
when these equipments are in redundant supply, is its estimated
replacement cost discounted at the percentage rate of its interest and
current supplementary costs to the prospective date of absorption of
the redundancy.
同様にして、船や工場や機械が供給過剰になったときの使用費用は、その設備の推定交換費用から、余剰が吸収される将来の日までの当期補足費用と利子率を引いた割引価値（＝現在価値）である。
We have assumed above that the equipment will be replaced in due
course by an identical article. If the equipment in question will not
be renewed identically when it is worn out, then its user cost has to
be calculated by taking a proportion of the user cost of the new
equipment, which will be erected to do its work when it is discarded,
given by its comparative efficiency.
上記においては設備は将来同種のものに交換されると想定されていた。しかし、問題の設備が消耗したときに同じものに交換できない場合、その設備の使用費用
は、古い設備が廃棄される時に代わりに設置される新しい設備の使用費用を設備の相対的な効率の度合いで換算して計算されなければならない。
III
The reader should notice that, where the equipment is not
obsolescent but merely redundant for the time being, the difference
between the actual user cost and its normal value (i.e. the value when
there is no redundant equipment) varies with the interval of time which
is expected to elapse before the redundancy is absorbed. Thus if the
type of equipment in question is of all ages and not “bunched' so that
a fair proportion is reaching the end of its life annually, the
marginal user cost will not decline greatly unless the redundancy is
exceptionally excessive. In the case of a general slump, marginal user
cost will depend on how long entrepreneurs expect the slump to last.
Thus the rise in the supply price when affairs begin to mend may be
partly due to a sharp increase in marginal user cost due to a revision
of their expectations.
第３節
読者が注意しなければならないのは、設備が旧式になったのではなく単に当面余っているだけの場合には、今の使用費用と設備の標準価格（つまり余剰設備がな
くなったときの値）の差は、その余剰が吸収されるまでにかかると予想される期間によって異なるということである。だから、問題となる設備のタイプが全部同
じ種類ではなく様々な寿命のものからなっていて、毎年かなりの割合が寿命を終える場合には、余剰が例外的に過度でない限り、限界使用費用が大きく低下する
ことはない。全般的な不況の場合には、限界使用費用はその不況がどれくらい続くかについての企業家たちの予想に依存する。だから、景気が好転しはじめた時
の供給価格の上昇は、一部は企業家たちの予想の更新によって生じた限界使用費用の急激な増加によって起こるのである。
It has sometimes been argued, contrary to the opinion of
business men, that organised schemes for scrapping redundant plant
cannot have the desired effect of raising prices unless they apply to
the whole of the redundant plant. But the concept of user cost shows
how the scrapping of (say) half the redundant plant may have the effect
of raising prices immediately. For by bringing the date of the
absorption of the redundancy nearer, this policy raises marginal user
cost and consequently increases the current supply price. Thus business
men would seem to have the notion of user cost implicitly in mind,
though they do not formulate it distinctly.
実業家たちの意見に反して、余剰施設の廃棄を組織的に計画しても、それが余剰施設全体に及ばない限り、価格を引き上げる望ましい効果は得られないと主張さ
れてきた。しかし、使用費用の考え方からすれば、たとえ半分でも余剰施設を廃棄すれば直ちに価格を引き上げる効果があることになる。というのは、この方針
に従えば余剰分が吸収される日が早まるので、限界使用費用は増加してその結果当期の供給価格が上昇するからである。つまり、実業家たちは使用費用の考え方
をはっきり表明してはいないが、暗黙のうちに心に留めているのだ。
If the supplementary cost is heavy, it follows that the marginal
user cost will be low when there is surplus equipment. Moreover, where
there is surplus equipment, the marginal factor and user costs are
unlikely to be much in excess of their average value. If both these
conditions are fulfilled, the existence of surplus equipment is likely
to lead to the entrepreneur's working at a net loss, and perhaps at a
heavy net loss. There will not be a sudden transition from this state
of affairs to a normal profit, taking place at the moment when the
redundancy is absorbed. As the redundancy becomes less, the user cost
will gradually increase; and the excess of marginal over average factor
and user cost may also gradually increase.
もし補足費用が大きいと、余剰設備がある場合には限界使用費用は小さくなる。さらに、余剰設備がある場合、限界要素費用と限界使用費用はそれぞれの平均値
を大きく上回りそうにない。つまり、両方の条件が揃っている場合には、余剰設備の存在は企業家に純損失、しかも恐らくひどい純損失のもとでの操業を余儀な
くさせると思われる。この状態から正常利潤に急速に移行することはできず、それは余剰が吸収された時にやっと実現される。余剰が減少するに従って、使用費
用は次第に上昇する。そして限界要素費用と限界使用費用も平均要素費用と平均使用費用をそれぞれ次第に上回るようになるのである。
IV
In Marshall's Principles of Economics (6th ed. p. 360) a part of
user cost is included in prime-cost under the heading of
“extra（余分な、特別な、追加の、限界的な） wear-and-tear of plant”. But no guidance is
given as to how this item is to be calculated or as to its importance.
In his Theory of Unemployment (p. 42) Professor Pigou expressly assumes
that the marginal disinvestment in equipment due to the marginal output
can, in general, be neglected: “The differences in the quantity of
wear-and-tear suffered by equipment and in the costs of non-manual
labour employed, that are associated with differences in output, are
ignored, as being, in general, of secondary importance”.[11] Indeed,
the notion that the disinvestment in equipment is zero at the margin of
production runs through a good deal of recent economic theory. But the
whole problem is brought to an obvious head as soon as it is thought
necessary to explain exactly what is meant by the supply price of an
individual firm.
第４節
マーシャルの『経済学原理』（第６版360頁）では、使用費用の一部が「施設の追加的消耗」という項目のなかに含まれている。しかし、この項目の計算方法
も重要性の説明も何もない。ピグー教授は『失業理論』（４２頁）のなかで、限界産出量による設備の限界マイナス投資（＝既出）は普通は無視してよいとはっ
きり言っている。「産出量の変化に伴う設備の消耗量と非肉体労働の雇用費用の変化はふつう二次的な重要性しかないので無視できる」と[１１]。確かに、設
備のマイナス投資は生産の限界状況ではゼロになるという考え方は最近の多くの経済理論に広まっている。しかし、個々の企業の供給価格が意味するものを正確
に説明する必要性に思い及ぶやいなや、問題の全体像は明らかになるのである。
It is true that the cost of maintenance of idle plant may often,
for the reasons given above, reduce the magnitude of marginal user
cost, especially in a slump which is expected to last a long time.
Nevertheless a very low user cost at the margin is not a characteristic
of the short period as such, but of particular situations and types of
equipment where the cost of maintaining idle plant happens to be heavy,
and of those disequilibria（不均衡） which are characterised by very rapid
obsolescence or great redundancy, especially if it is coupled with a
large proportion of comparatively new plant.
遊休施設の維持費は上記の理由によって限界使用費用の額を減少させる。不況の長期化が予想される場合はとくにそうである。しかし、限界使用費用が非常に低
くなることは短期の特徴ではない。それは、設備の状況や設備のタイプが特殊なために遊休施設の維持費が大きくなる場合の特徴であり、また世の中が不安定に
なって設備の旧式化が早まったり余剰が増大した場合の特徴である。特に、比較的新しい施設の割合が大きい時にそうなりがちである。
In the case of raw materials the necessity of allowing for user
cost is obvious;― if a ton of copper is used up to-day it cannot be
used to-morrow, and the value which the copper would have for the
purposes of to-morrow must clearly be reckoned as a part of the
marginal cost. But the fact has been overlooked that copper is only an
extreme case of what occurs whenever capital equipment is used to
produce. The assumption that there is a sharp division between raw
materials where we must allow for the disinvestment due to using them
and fixed capital where we can safely neglect it, does not correspond
to the facts; ― especially in normal conditions where equipment is
falling due for replacement every year and the use of equipment brings
nearer the date at which replacement is necessary.
原材料の場合に使用費用を考慮しなければならないのは明らかである。もし１トンの銅を今日使い切ったら明日には使えない。だから、明日のために銅がもって
いる価値は明らかに限界費用の一部として計算されねばならない。しかし、銅の例は資本設備が生産に使われる時に何が起こるかを示す極端な一例でしかない、
という事実は見過ごされてきた。使用すればマイナス投資が生ずることを考慮しなければならない原材料と、それを無視できる固定資本（＝建物や機械など）の
間には明確な違いがあるとする考え方は事実に反している。設備が毎年交換時期に至ったり、設備を使用すれば交換が必要な日が近づいてくるという普通の状況
では特にそうである。
It is an advantage of the concepts of user cost and
supplementary cost that they are as applicable to working and liquid
capital as to fixed capital. The essential difference between raw
materials and fixed capital lies not in their liability to user and
supplementary costs, but in the fact that the return to liquid capital
consists of a single term; whereas in the case of fixed capital, which
is durable and used up gradually, the return consists of a series of
user costs and profits earned in successive periods.
使用費用と補足費用の考え方の利点は、運転資本と流動資本だけでなく固定資本にも適用できることである。原材料と固定資本の間の重要な違いは使用費用と補
足費用が必要かどうかの違いではなく、流動資本の収益は一期であるのに対して、固定資本の場合には耐久性があって徐々に使い切るので、その利益を構成する
使用費用と利潤は何期にもわたることである。
Author's Footnotes
[7]. This way of putting it depends on the convenient assumption that
the marginal prime-cost curve is continuous throughout its length for
changes in output. In fact, this assumption is often unrealistic, and
there may be one or more points of discontinuity, especially when we
reach an output corresponding to the technical full capacity of the
equipment. In this case the marginal analysis partially breaks down;
and the price may exceed the marginal prime-cost, where the latter is
reckoned in respect of a small decrease of output. (Similarly there may
often be a discontinuity in the downward direction. i.e. for a
reduction in output below a certain point). This is important when we
are considering the short-period supply price in long-period
equilibrium, since in that case any discontinuities, which may exist
corresponding to a point of technical full capacity, must be supposed
to be in operation. Thus the short-period supply price in long-period
equilibrium may have to exceed the marginal prime-cost (reckoned in
terms of a small decrease of output).
[8]. Since user cost partly depends on expectations as to the future
level of wages, a reduction in the wage-unit which is expected to be
short-lived will cause factor cost and user cost to move in different
proportions and so affect what equipment is used, and, conceivably, the
level of effective demand, since factor cost may enter into the
determination of effective demand in a different way from user cost.
[9]. The user cost of the equipment which is first brought into use is
not necessarily independent of the total volume of output (see below);
i.e. the user cost may be affected all along the line when the total
volume of output is changed.（ネットのテキストではnot necessarilyがnot
onlyになっていることが多い）
[10]. It will be more when it is expected that a more than normal yield
can be obtained at some later date, which, however, is not expected to
last long enough to justify (or give time for) the production of new
equipment. To-day's user cost is equal to the maximum of the discounted
values of the potential expected yields of all the tomorrows.
[11]. Mr. Hawtrey (Economica, May 1934, p. 145) has called attention to
Prof. Pigou's identification of supply price with marginal labour cost,
and has contended that Prof. Pigou's argument is thereby seriously
vitiated.
著者注
[７]
この構成の仕方は、限界主要費用の曲線は産出量の変化に応じて全体にわたって連続しているという便宜的な仮定に依存している。しかし、この仮定はあまり現
実的ではなく、とくに産出量が設備の技術力の頂点に達した場合には、不連続点が発生する可能性がある。この場合には、限界分析は部分的に働かなくなる。そ
して価格は限界主要費用を上回る可能性がある。この場合には、限界主要費用は産出量の僅かな減少を考慮して計算されるからである。（同様にして曲線が下向
きの場合、つまり産出量がある点以下に減少する場合にも不連続点が発生する可能性がある）。これは長期均衡状態における短期供給価格を検討する場合に重要
である。なぜなら、この場合には技術力の頂点に発生するような不連続点がいつでも起きると考えなければならないからである。だから、長期均衡状態における
短期供給価格は限界主要費用（産出量の僅かの減少に応じて計算された）を上回ると考えなければならない。
[８]
使用費用は将来の賃金レベルについての予想に一部を依存するため、一時的だと思われる単位賃金の引き下げによって、要素費用（＝賃金）と使用費用は異なっ
た割合で変動して、そのために企業家による設備の選び方が違ってくるし、有効需要のレベルも違ってくる。なぜなら、要素費用は使用費用とは違うやり方で有
効需要の決定に関与してくるからである。
[９] 最初に使用される設備の使用費用は総産出量と必ずしも無関係であるわけではない（以下を見よ）、この使用費用は総産出量が変化するにつれて変わってくる可能性がある。
[１０]
使用費用がそれ以上になるのは、通常収益以上の収益が後に得られると予想できるが、その収益は新たな設備を自分で作れるほど長くは続くないと思われる場合
である。今日の使用費用は明日以降の潜在的な予想収益の割引価値（＝現在価値）の最大値と等しいのである。
[１１] ホートレー氏（『エコノミカ』1934年5月145頁）はピグー教授が供給価格と限界労働費用を同一視していることに注目して、ピグー教授の議論はそれによって著しく価値を損なっていると主張している。
Chapter 7. The Meaning of Saving and Investment Further Considered
第７章 貯蓄と投資の意味の再考
I
IN the previous chapter Saving and Investment have been so
defined that they are necessarily equal in amount, being, for the
community as a whole, merely different aspects of the same thing.
Several contemporary writers (including myself in my Treatise on Money)
have, however, given special definitions of these terms on which they
are not necessarily equal. Others have written on the assumption that
they may be unequal without prefacing their discussion with any
definitions at all. It will be useful, therefore, with a view to
relating the foregoing to other discussions of these terms, to classify
some of the various uses of them which appear to be current.
第１節
前の章で「貯蓄」と「投資」は必ず同額であり、社会全体にとっては両者は同じ物の異なる二つの面でしかないと定義された。しかし、多くの現代の学者（『貨
幣論』を書いた私を含めて）はこれらの用語に特殊な定義をほどこして両者は必ずしも等しくないと言っている。また、他の学者は全く定義もせず前置きもなく
両者は一致しないことがあることを前提にしている。だから、これらの用語についてのこれまでの議論をそのほかの議論と結びつけるために、現在見ることの出
来るこの用語の様々な用法を分類してみるのは有益だろう。
So far as I know, everyone agrees in meaning by Saving the
excess of income over what is spent on consumption. It would certainly
be very inconvenient and misleading not to mean this. Nor is there any
important difference of opinion as to what is meant by expenditure on
consumption. Thus the differences of usage arise either out of the
definition of Investment or out of that of Income.
私の知る限り、「貯蓄」が所得から消費支出を引いた余りであることを意味する点は誰もが一致している。もしそうでなければ非常に不便だろうし紛らわしいこ
とになるのは必定である。「消費支出」の意味についても重大な意見の違いはない。したがって、用語の混乱の原因は「投資」の定義か「所得」の定義にあるこ
とになる。
II
Let us take Investment first. In popular usage it is common to
mean by this the purchase of an asset, old or new, by an individual or
a corporation. Occasionally, the term might be restricted to the
purchase of an asset on the Stock Exchange. But we speak just as
readily of investing, for example, in a house, or in a machine, or in a
stock of finished or unfinished goods; and, broadly speaking, new
investment, as distinguished from reinvestment, means the purchase of a
capital asset of any kind out of income. If we reckon the sale of an
investment as being negative investment, i.e. disinvestment, my own
definition is in accordance with popular usage; since exchanges of old
investments necessarily cancel out.
第２節
「投資」から始めよう。一般的な用法では投資とは個人や企業による新旧の資産の購入を意味するのが普通である。時には、この用語は証券市場での資産の購入
に限定されることがあるかもしれない。しかし、我々は例えば家や機械あるいは完成品や未完成品の在庫に対しても同じ様に投資すると言う。そして、広い意味
で「新投資」とは「再投資」と区別して、所得によって何らかの資本資産を購入することを意味する。もし投資の売却を負の投資、すなわちマイナス投資とみな
すなら、私自身の定義は一般的な用法と合致している。なぜなら古い投資の売りと買いは必ず釣り合っているからである。
We have, indeed, to adjust for the creation and discharge of debts
(including changes in the quantity of credit or money); but since for
the community as a whole the increase or decrease of the aggregate
creditor position is always exactly equal to the increase or decrease
of the aggregate debtor position, this complication also cancels out
when we are dealing with aggregate investment. Thus, assuming that
income in the popular sense corresponds to my net income, aggregate
investment in the popular sense coincides with my definition of net
investment, namely the net addition to all kinds of capital equipment,
after allowing for those changes in the value of the old capital
equipment which are taken into account in reckoning net income.
もちろん、債務の創設と解消（信用や貨幣の量の変更を含む）を勘案すべきではある。しかし、社会全体として債権者の立場にいる人の総数の増減はつねに債務
者の立場にいる人の増減とぴったり一致するので、我々が「総投資」を扱うときには、この複雑な現象（＝債務の創設と解消）は釣り合っているのである。だか
ら、一般的な意味の所得が私の言う「純所得」と一致すると考えるなら、一般的な意味での「総投資」は私の定義する「純投資」と一致する。即ち、総投資と
は、古い資本設備の価値のうちで純所得の計算に含まれる価格の変化（＝使用費用と補足費用）を考慮した、あらゆる種類の資本設備に対する純追加（＝既出）
なのである。
Investment, thus defined, includes, therefore, the increment of
capital equipment, whether it consists of fixed capital, working
capital or liquid capital; and the significant differences of
definition (apart from the distinction between investment and net
investment) are due to the exclusion from investment of one or more of
these categories.
したがって、このように定義された投資は資本設備の増加であり、それが固定資本、運転資本、流動資本であるかに関わらない。そして様々な定義の違いは主に（投資と純投資の違いを別にして）投資からこれらの種類の資本のいくつかを除外することから来ている。
Mr. Hawtrey, for example, who attaches great importance to
changes in liquid capital, i.e. to undesigned increments (or
decrements) in the stock of unsold goods, has suggested a possible
definition of investment from which such changes are excluded. In this
case an excess of saving over investment would be the same thing as an
undesigned increment in the stock of unsold goods, i.e. as an increase
of liquid capital. Mr. Hawtrey has not convinced me that this is the
factor to stress; for it lays all the emphasis on the correction of
changes which were in the first instance unforeseen, as compared with
those which are, rightly or wrongly, anticipated.
例えば、ホートレー氏は流動資本の変化に、即ち売れ残り品の在庫の予期せぬ増減に重きを置いたので、流動資本の変化を除外した投資の定義を提案している。
この場合には、貯蓄が投資を上回る分が、売れ残り品の在庫の予期せぬ増加、つまり流動資本の増加と同じものとなる。これが強調すべき要素であるというホー
トレー氏の意見は私には説得力がなかった。というのは、彼の説は、良かれ悪しかれ予想される変化よりは、むしろ最初に予想されなかった変化の修正に全ての
力点を置いているからである。
Mr. Hawtrey regards the daily decisions of entrepreneurs concerning
their scale of output as being varied from the scale of the previous
day by reference to the changes in their stock of unsold goods.
Certainly, in the case of consumption goods, this plays an important
part in their decisions. But I see no object in excluding the play of
other factors on their decisions; and I prefer, therefore, to emphasise
the total change of effective demand and not merely that part of the
change in effective demand which reflects the increase or decrease of
unsold stocks in the previous period. Moreover, in the case of fixed
capital, the increase or decrease of unused capacity corresponds to the
increase or decrease in unsold stocks in its effect on decisions to
produce; and I do not see how Mr. Hawtrey's method can handle this at
least equally important factor.
ホートレー氏は、企業家が日々決定する産出量は、売れ残り品の在庫の変化に応じて前日の産出量から変化すると考える。確かに消費財の場合、これは企業家の
決定に重要な役割を果たす。しかし、企業家の決定に及ぼす他の要素の役割を除外するのは無意味だと思う。だから、私はむしろ有効需要の全体的な変化を強調
すべきであって、有効需要の変化のうちで前期の売れ残り品の在庫の増減を反映する部分だけを強調すべきだとは思わない。さらに、固定資本（＝機械など）の
場合、使われていない能力の増減は、生産決定に対する影響力の点では、売れ残り品の在庫の増減に匹敵する。そして、少なくとも同程度に重要なこの要素を
ホートレー氏の方法がどう扱うか私には分からないのである。
It seems probable that capital formation and capital
consumption, as used by the Austrian school of economists, are not
identical either with investment and disinvestment as defined above or
with net investment and disinvestment. In particular, capital
consumption is said to occur in circumstances where there is quite
clearly no net decrease in capital equipment as defined above. I have,
however, been unable to discover a reference to any passage where the
meaning of these terms is clearly explained. The statement, for
example, that capital formation occurs when there is a lengthening of
the period of production does not much advance matters.
オーストリア学派の経済学者によって使われている資本形成と資本消費という用語はおそらく上で定義した投資とマイナス投資とも純投資とマイナス純投資とも
一致しないと思われる。特に、資本消費は上で定義した資本設備の純減価（＝使用費用と補足費用を含まない）が全くないことが明らかな状況で起きると言われ
ている。しかし、私はこれらの用語の意味が明快に説明されているところを見たことがない。例えば、資本形成は生産期間が長期化するときに起こると言ったと
ころで、事態はたいして何も変わらないのだ。
III
We come next to the divergences between saving and investment
which are due to a special definition of income and hence of the excess
of income over consumption. My own use of terms in my Treatise on Money
is an example of this. For, as I have explained in Chapter 6 above, the
definition of income, which I there employed, differed from my present
definition by reckoning as the income of entrepreneurs not their
actually realised profits but (in some sense) their “normal profit”.
Thus by an excess of saving over investment I meant that the scale of
output was such that entrepreneurs were earning a less than normal
profit from their ownership of the capital equipment; and by an
increased excess of saving over investment I meant that a decline was
taking place in the actual profits, so that they would be under a
motive to contract output.
第３節
次に、所得の特殊な定義および所得が消費を上回る分の特殊な定義に起因する貯蓄と投資の不一致に移ろう。私の『貨幣論』での用語の使い方はこの一例であ
る。というのは、前の第６章で説明したように、あの本の中で使っている所得の定義は私の今の定義とは違って、実際に実現された利潤ではなく（ある意味で）
企業家の「正常利潤」を企業家の所得とみなしているからである（＝既出）。そして、そこで私は、貯蓄が投資を上回るということは、産出量が少なくて自分の
資本設備から企業家が得られる利潤が正常利潤以下であることを意味し、また貯蓄が投資を上回る分が増えるということは、実利潤が低下して、企業家は産出量
を縮小しようとしていることを意味していた。
As I now think, the volume of employment (and consequently of output
and real income) is fixed by the entrepreneur under the motive of
seeking to maximise its present and prospective profits (the allowance
for user cost being determined by his view as to the use of equipment
which will maximise his return from it over its whole life); whilst the
volume of employment which will maximise his profit depends on the
aggregate demand function given by his expectations of the sum of the
proceeds resulting from consumption and investment respectively on
various hypotheses. In my Treatise on Money the concept of changes in
the excess of investment over saving, as there defined, was a way of
handling changes in profit, though I did not in that book distinguish
clearly between expected and realised results.[1] I there argued that
change in the excess of investment over saving was the motive force
governing changes in the volume of output.
今考えるに、企業家は現在と将来の利潤を最大化しようとする動機のもとで雇用量（それは結果的には産出量と実質賃金の量になる）を決めるものである（＝第
３章２節に既出）（使用費用の計算は設備の寿命が終わるまでに得られる収益を最大化するような設備の利用法についての企業家の考え方によって決まる）。一
方、企業家の利潤を最大化する雇用量は総需要関数によって与えられる。この総需要関数は様々な仮定のもと消費と投資の両方から生まれる売上合計に対する企
業家の予想値によって与えられる。『貨幣論』のなかで、私は予想された結果と実現された結果を明確に区別していなかったが[１]、投資があの本で定義され
た貯蓄を上回る分（＝上記と逆）の「変化」を考えることは、利潤の変化を扱う方法だった。私があの本で主張したことは、投資が貯蓄を上回る分の変化は、産
出量の変化を左右する要因だということなのである。
Thus the new argument, though (as I now think) much more accurate and
instructive, is essentially a development of the old. Expressed in the
language of my Treatise on Money, it would run: the expectation of an
increased excess of Investment over Saving, given the former volume of
employment and output, will induce entrepreneurs to increase the volume
of employment and output. The significance of both my present and my
former arguments lies in their attempt to show that the volume of
employment is determined by the estimates of effective demand made by
the entrepreneurs, an expected increase of investment relatively to
saving as defined in my Treatise on Money being a criterion of an
increase in effective demand. But the exposition in my Treatise on
Money is, of course, very confusing and incomplete in the light of the
further developments here set forth.
だから、今回の新たな議論は、以前の議論よりもはるかに正確で役に立つものだと思っているが、基本的には以前の議論の発展である。『貨幣論』の中の言葉遣
いを使えば「以前の雇用量と産出量のもと、投資が貯蓄を上回る分が増加すると予想できるなら、企業家は雇用量と産出量を増やそうとするだろう」となる。私
の現在の議論と以前の議論の意義は両方とも、『貨幣論』で定義された貯蓄に対する投資の相対的な増加の予想値が有効需要の増加の尺度であり、雇用量を決め
るのは有効需要に対する企業家の推測であることを示す点にある。しかし、『貨幣論』のなかの表現は、本書で提示された議論の進展からも見れが、当然なが
ら、非常に紛らわしく不完全なものである。
Mr. D. H. Robertson has defined to-day's income as being equal
to yesterday's consumption plus investment, so that to-day's saving, in
his sense, is equal to yesterday's investment plus the excess of
yesterday's consumption over to-day's consumption. On this definition
saving can exceed investment, namely, by the excess of yesterday's
income (in my sense) over to-day's income. Thus when Mr. Robertson says
that there is an excess of saving over investment, he means literally
the same thing as I mean when I say that income is falling, and the
excess of saving in his sense is exactly equal to the decline of income
in my sense. If it were true that current expectations were always
determined by yesterday's realised results, to-day's effective demand
would be equal to yesterday's income. Thus Mr. Robertson's method might
be regarded as an alternative attempt to mine (being, perhaps, a first
approximation to it) to make the same distinction, so vital for causal
analysis, that I have tried to make by the contrast between effective
demand and income.[2]
Ｄ.Ｈ.ロバートソン氏は、今日の所得は「昨日の消費＋投資」と等しいと定義している。だから、彼の言う意味では今日の貯蓄は「昨日の投資＋昨日の消費－
今日の消費」に等しくなる。即ち、この定義では貯蓄が投資を上回るのは「昨日の所得」（私の意味での）が「今日の所得」を上回る分だけということになる。
つまり、貯蓄が投資を上回るとロバートソン氏が言う時、それは私が「所得が低下する」と言うのとまったく同じ事を意味しており、彼の言う「貯蓄の超過」
は、私の言う「所得の低下」とちょうど同じことを意味している。もし仮に、現在の予想が昨日実現された結果によって常に決まるというのが真実なら、今日の
有効需要は昨日の所得と等しいことになる。つまり、ロバートソン氏の方法は私の方法と代替可能な試み（多分最も私の方法に近いもの）と見做すことが出来る
かもしれない。彼の方法はまさに原因分析にとって決め手となる区別（＝予想された結果と実現された結果の区別）、私が有効需要と所得の対比によって行おう
とした区別と同じ区別をしているからである。[２]
IV
We come next to the much vaguer ideas associated with the phrase
“forced saving”. Is any clear significance discoverable in these? In my
Treatise on Money (vol. i. p. 171, footnote) I gave some references to
earlier uses of this phrase and suggested that they bore some affinity
to the difference between investment and “saving” in the sense in which
I there used the latter term. I am no longer confident that there was
in fact so much affinity as I then supposed. In any case, I feel sure
that “forced saving” and analogous phrases employed more recently (e.g.
by Professor Hayek or Professor Robbins) have no definite relation to
the difference between investment and “saving” in the sense intended in
my Treatise on Money. For whilst these authors have not explained
exactly what they mean by this term, it is clear that “forced saving”,
in their sense, is a phenomenon which results directly from, and is
measured by, changes in the quantity of money or bank-credit.
第４節
次に「強制貯蓄」（＝インフレ下で消費を控えるため貯蓄が増えるように見えること）という言葉と結びついたかなり曖昧な考え方を扱おう。この考え方のなか
に何か重要なものが見い出せるだろうか。『貨幣論』（第１巻171頁脚注）で私はこの言葉のもっと古い使用例に言及して、それが投資と「貯蓄」（あの本の
意味による）との差額に似ていると言った。今では当時思ったほど実際にそれほどの類似性があるか自信はない。いづれにせよ、確かなのは「強制貯蓄」やそれ
と似た最近使われる言葉（例えばハイエク教授やロビンス教授のもの）は私が『貨幣論』の中で意図した意味での「貯蓄」と投資との差額とは何ら明確なつなが
りがないということである。というのは、これらの学者たちはこの言葉で何を意味するかを正確に説明していないが、彼らのいう意味での「強制貯蓄」とは貨幣
量や銀行信用（＝貸出金）の量の変化から直接的に生まれ、その変化によって測られる現象であることは明らかだからである。
It is evident that a change in the volume of output and
employment will, indeed, cause a change in income measured in
wage-units（単位賃金数）; that a change in the wage-unit will cause both a
redistribution of income between borrowers and lenders and a change in
aggregate income measured in money; and that in either event there will
(or may) be a change in the amount saved. Since, therefore, changes in
the quantity of money may result, through their effect on the rate of
interest, in a change in the volume and distribution of income (as we
shall show later), such changes may involve, indirectly, a change in
the amount saved.
確かに、（＝貨幣量の変化に起因する）産出量と雇用量の変化は単位賃金数で測った所得の変化をもたらし、単位賃金の変化は貸手と借手の間に所得の再分配を
もたらすだけでなく、名目総所得も変化させ、さらに、どちらの場合にも貯蓄高に変化（＝強制貯蓄）をもたらす（あるいはその可能性がある）のは明らかであ
る。したがって、貨幣量の変化は利子率への影響を通じて所得の量と分配に変化（後に見るような）をもたらす可能性があるから、貨幣量の変化が間接的に貯蓄
量の変化（＝強制貯蓄）をもたらす可能性はある。
But such changes in the amounts saved are no more “forced savings” than
any other changes in the amounts saved due to a change in
circumstances; and there is no means of distinguishing between one case
and another, unless we specify the amount saved in certain given
conditions as our norm or standard. Moreover, as we shall see, the
amount of the change in aggregate saving which results from a given
change in the quantity of money is highly variable and depends on many
other factors.
しかしながら、貯蓄量のこのような変化は決して「強制貯蓄」ではない。それは環境の変化によって貯蓄量に変化があった場合、それが強制貯蓄でないのと同じ
である。つまり特定の条件のもとでの貯蓄量を我々の判断基準あるいは標準として指定しない限り、強制貯蓄かどうかを区別する方法はない。さらに、後に見る
ように、貨幣量の変化から来る総貯蓄量の変化は非常に多様で、他の多くの原因に左右される。
Thus “forced saving” has no meaning until we have specified some
standard rate of saving. If we select (as might be reasonable) the rate
of saving which corresponds to an established state of full employment,
the above definition would become: “Forced saving is the excess of
actual saving over what would be saved if there were full employment in
a position of long-period equilibrium”. This definition would make good
sense, but a sense in which a forced excess of saving would be a very
rare and a very unstable phenomenon, and a forced deficiency of saving
the usual state of affairs.
つまり「強制貯蓄」は標準貯蓄率を指定しない限り意味が無いのである。もし確立した完全雇用状態に対応する貯蓄率を（そうすれば理にかなっているかもしれ
ない）標準貯蓄率に選ぶなら、上記の定義は次のようになる。「強制貯蓄とは長期均衡状態で完全雇用のときに行われる貯蓄を現実の貯蓄が上回る額である」。
この定義だとちゃんとした意味になるが、この場合、強制的な貯蓄超過は非常に珍しい不安定な現象で、強制的な貯蓄不足が普通の状態になるだろう。
Professor Hayek's interesting “Note on the Development of the
Doctrine of Forced Saving”[3] shows that this was in fact the original
meaning of the term. “Forced saving” or “forced frugality” was, in the
first instance, a conception of Bentham's; and Bentham expressly stated
that he had in mind the consequences of an increase in the quantity of
money (relatively to the quantity of things vendible for money) in
circumstances of “all hands being employed and employed in the most
advantageous manner”[4]. In such circumstances, Bentham points out,
real income cannot be increased, and, consequently, additional
investment, taking place as a result of the transition, involves forced
frugality “at the expense of national comfort and national justice”.
ハイエク教授の興味深い論文『強制貯蓄理論の発展についての覚書』[３]を見れば、これがこの言葉の元々の意味だったことがわかる。最初は「強制貯蓄」あ
るいは「強制倹約」はベンサムの考えだった。そしてベンサムは「全員が雇われており、しかも最も有利なように雇われている」状況で（貨幣によって購買可能
な品物の量に比べて）貨幣量が増加した結果について考えているとはっきり述べている[４]。そのような状況では実質所得が増加することは不可能なので、そ
の過渡期に起こる投資の増加は「国民の安寧と正義を犠牲にした」強制倹約を引き起こすとベンサムは指摘しているのだ。
All the nineteenth-century writers who dealt with this matter had
virtually the same idea in mind. But an attempt to extend this
perfectly clear notion to conditions of less than full employment
involves difficulties. It is true, of course (owing to the fact of
diminishing returns to an increase in the employment applied to a given
capital equipment), that any increase in employment involves some
sacrifice of real income to those who were already employed, but an
attempt to relate this loss to the increase in investment
which（先行詞はlossである） may accompany the increase in employment is not
likely to be fruitful. At any rate I am not aware of any attempt having
been made by the modern writers who are interested in “forced saving”
to extend the idea to conditions where employment is increasing; and
they seem, as a rule, to overlook the fact that the extension of the
Benthamite concept of forced frugality to conditions of less than full
employment requires some explanation or qualification.
この問題を扱う１９世紀の学者たちは全員がほとんど同じ考え方をしていた。しかし、この完全に明白な考えを不完全雇用の状況にまで押し広げて適用しようと
する試みは困難をともなう。もちろん（一定の資本設備に適用される雇用の増加に対して収益が次第に減少するという事実のために）雇用の「どんな」増加も既
存の被雇用者の実質賃金の低下を引き起こすのは事実であるが、雇用の増加に伴う実質賃金の低下を投資の増加に結びつけようとする試みは上手くいきそうにな
い。とにかく、強制貯蓄に関心のある現代の学者たちがこの考えを雇用が増加する状況にまで押し広げようとしたどんな試みも私は知らない。ベンサムの強制倹
約の考えを不完全雇用の状況に押し広げるためには若干の説明か条件付けが必要なことに、概して彼らは気付いていないようなのである。
V
The prevalence of the idea that saving and investment, taken in
their straightforward sense, can differ from one another, is to be
explained, I think, by an optical illusion due to regarding an
individual depositor's relation to his bank as being a one-sided
transaction, instead of seeing it as the two-sided transaction which it
actually is. It is supposed that a depositor and his bank can somehow
contrive between them to perform an operation by which savings can
disappear into the banking system so that they are lost to investment,
or, contrariwise, that the banking system can make it possible for
investment to occur, to which no saving corresponds.
第５節
貯蓄と投資を素直な意味にとってこの二つが互いに一致しない可能性があるとする考え方が広まっているが、その理由は、私が思うに、個人の預金者と銀行との
関係は実際には二つの面がある取り引きなのに、それを一つの意味しかない取り引きだとする思い込みによって説明できる。つまり、預金者と銀行が一緒になっ
てどうにかして預金が銀行の中に消えてしまい投資に回らないように出来るとか、あるいは逆に、銀行は預金とは無関係に投資を発生させることが出来ると思わ
れているのだ。
But no one can save without acquiring an asset, whether it be cash or a
debt or capital-goods; and no one can acquire an asset which he did not
previously possess, unless either an asset of equal value is newly
produced or someone else parts with an asset of that value which he
previously had. In the first alternative there is a corresponding new
investment: in the second alternative someone else must be dissaving an
equal sum.
しかし、人は誰しも何らかの貯蓄をする時には必ず何らかの資産（それが現金であれ債務であれ資本財であるかは問わない）を獲得している。そして、人がそれ
まで持っていなかった資産を獲得するためには、同じ価値の資産が新たに生産されるか、あるいは誰か他の人がそれまで持っていた同じ価値の資産を手放さなけ
ればならない。最初の場合は、それに対応する新投資が行われるのであり、二番目の場合は、誰か他の人が同じ額の貯蓄を引き出さねばならない。
For his loss of wealth must be due to his consumption exceeding his
income, and not to a loss on capital account through a change in the
value of a capital-asset, since it is not a case of his suffering a
loss of value which his asset formerly had; he is duly receiving the
current value of his asset and yet is not retaining this value in
wealth of any form, i.e. he must be spending it on current consumption
in excess of current income. Moreover, if it is the banking system
which parts with an asset, someone must be parting with cash. It
follows that the aggregate saving of the first individual and of others
taken together must necessarily be equal to the amount of current new
investment.
というのは、後者の富の喪失は所得を上回る消費の結果であり、資本資産の価値の変化による資産勘定のマイナスのせいではない。なぜなら、この場合、彼の資
産が以前に持っていた価値は損なわれていないからである。彼は（＝預金を引き出して）まさに現在の資産の価値を受取ながら、しかもこの価値をどのような富
の形でももう所有していない。彼はその富を現在の所得を上回る消費に支出しているに違いないのである。さらに、もし銀行から資産が離れていったのなら、そ
れは誰かが現金を手放しているに違いない。こうして、最初の人とそのほかの人達の貯蓄をひとまとめにした総貯蓄は現在の新たな投資量と必然的に等しくなら
ざるを得ないのである。
The notion that the creation of credit（信用創造、貨幣創造） by the banking
system allows investment to take place to which “no genuine
saving（真正貯蓄）” corresponds can only be the result of isolating one of
the consequences of the increased bank-credit to the exclusion of the
others. If the grant of a bank-credit to an entrepreneur additional to
the credits already existing allows him to make an addition to current
investment which（先行詞はaddition） would not have occurred otherwise,
incomes will necessarily be increased and at a rate which will normally
exceed the rate of increased investment. Moreover, except in conditions
of full employment, there will be an increase of real income as well as
of money-income.
銀行は信用創造（＝銀行が貸出をすること『マンキュー経済学ＩＩ』ｐ３２０）によって「真正な貯蓄」と何の対応もない投資を発生させているという考え方が
あるが、それは銀行信用（＝貸出金）の増加で起こる様々なことのうちの一つの事を取り立てて強調して他の事を無視した結果である。もしある企業家に対して
銀行信用が供与されて、既に存在する信用（＝借入金）に追加されることによって、その企業家が現在の投資に対して他の方法では発生しないような追加の投資
を行うことができた場合には、必然的に総所得が増加する。しかも、それはふつう投資の増加率を上回る率で増えるのである。さらに、完全雇用の状態でなけれ
ば、名目賃金も実質賃金も増えるのである（＝信用創造に対応する貯蓄が可能となる）。
The public will exercise “a free choice” as to the proportion in which
they divide their increase of income between saving and spending; and
it is impossible that the intention of the entrepreneur who has
borrowed in order to increase investment can become effective (except
in substitution for investment by other entrepreneurs which would have
occurred otherwise) at a faster rate than the public decide to increase
their savings. Moreover, the savings which result from this decision
are just as genuine as any other savings. No one can be compelled to
own the additional money corresponding to the new bank-credit, unless
he deliberately prefers to hold more money rather than some other form
of wealth. Yet employment, incomes and prices cannot help moving in
such a way that in the new situation someone does choose to hold the
additional money.
社会はその所得の増加分を貯蓄と支出に振り分ける割合について「自由選択権」をもっている。しかも、企業家が借金（＝信用創造）して投資を増やそうとして
も（他の企業家が借金以外の方法で行えたはずの投資を代行するのでないかぎり）、社会が貯蓄を増やすことを決める前にそれを実行することは不可能である。
さらに、社会のこの決定から生まれる貯蓄はまさに他のどの貯蓄とも同じ真正な貯蓄である（＝信用創造に対応する真正な貯蓄）。確かに、他の富の形態ではな
くより多くの貨幣を意図的に保有（＝貯蓄）しようとする場合は別として、新たな銀行信用（＝信用創造）に対応する追加の貨幣を誰かに強制的に保有（＝真正
な貯蓄を）させることは出来ない。しかし、雇用と所得と物価が変動していくと、新たな状況の中で必ず誰かが追加の貨幣を保有するようになるのである。
It is true that an unexpected increase of investment in a
particular direction may cause an irregularity in the rate of aggregate
saving and investment which would not have occurred if it has been
sufficiently foreseen. It is also true that the grant of the
bank-credit will set up three tendencies (1) for output to increase,
(2) for the marginal product to rise in value in terms of the wage-unit
(which in conditions of decreasing return must necessarily accompany an
increase of output), and (3) for the wage-unit to rise in terms of
money (since this is a frequent concomitant（付随物） of better employment);
and these tendencies may affect the distribution of real income between
different groups. But these tendencies are characteristic of a state of
increasing output as such, and will occur just as much if the increase
in output has been initiated otherwise than by an increase in
bank-credit. They can only be avoided, by avoiding any course of action
capable of improving employment. Much of the above, however, is
anticipating the result of discussions which have not yet been reached.
確かに、特定の方面での投資の予期せぬ増加は、総貯蓄と総投資の割合に不規則性を、しかも投資の増加が充分予想された場合には起こらないような不規則性を
もたらすだろう。また、銀行信用の供与が次の三つの傾向をもたらすのは事実である。（１）産出量の増加、（２）単位賃金で測った限界生産物の価格の上昇
（収益の減少という状況ではそれは必然的に産出量の増加を伴う）、（３）名目単位賃金の上昇（これはしばしば雇用の改善に付随するからである）。しかもこ
の三つの傾向は、異なる集団間への実質所得の分配に影響する可能性がある。しかし、これらは産出量が増加する状況それ自身の特徴であるから、産出量の増加
が銀行信用の増加以外の原因で始まった場合にも、同じようにこれらは発生する。これらの傾向を回避するには、雇用を改善させるようなあらゆる方針を回避す
るしかない。しかし、上記の多くは今後行われる議論の結論を先取りするものである。
Thus the old-fashioned view that saving always involves
investment, though incomplete and misleading, is formally sounder than
the newfangled（流行の） view that there can be saving without investment or
investment without “genuine” saving. The error lies in proceeding to
the plausible inference that, when an individual saves, he will
increase aggregate investment by an equal amount. It is true, that,
when an individual saves he increases his own wealth. But the
conclusion that he also increases aggregate wealth fails to allow for
the possibility that an act of individual saving may react on someone
else's savings and hence on someone else's wealth.
つまり、貯蓄はつねに投資を引き起こすという昔から存在する考え方は不完全であり紛らわしいものだが、投資なしの貯蓄、あるいは「真正な貯蓄」なしの投資
が存在しうるとする最近の物の見方よりは、明らかに健全である。個人が貯蓄するとき彼は総投資を同じ量だけ増やしているという妥当な結論に至るまでの過程
に間違いが存在するのだ。確かに、個人が貯蓄をするときに彼は自分の富を増やしている。しかし、彼は同時に富の総体を増やしているとする結論は、個人の貯
蓄行為が他の誰かの貯蓄に逆の作用を及ぼして（＝減らす）、その結果、他の誰かの富に逆の作用を及ぼす（＝他人の富を減らす）可能性を見落としている。
The reconciliation of the identity between saving and investment
with the apparent “free-will” of the individual to save what he chooses
irrespective of what he or others may be investing, essentially depends
on saving being, like spending, a two-sided affair. For although the
amount of his own saving is unlikely to have any significant influence
on his own income, the reactions of the amount of his consumption on
the incomes of others makes it impossible for all individuals
simultaneously to save any given sums. Every such attempt to save more
by reducing consumption will so affect incomes that the attempt
necessarily defeats itself. It is, of course, just as impossible for
the community as a whole to save less than the amount of current
investment, since the attempt to do so will necessarily raise incomes
to a level at which the sums which individuals choose to save add up to
a figure exactly equal to the amount of investment.
貯蓄と投資が一致するという事実と、個人が自分や他人の投資量に無関係に好きなだけ貯蓄する明らかな「自由意志」とが調和するのは、本質的に貯蓄が支出と
同じく二面性のある出来事だからである。というのは、自分の貯蓄量が自分の所得に大きく影響しそうにないにもかかわらず、自分の消費量が他人の所得に作用
を及ぼす（＝消費を減らして貯蓄を増やすと他人の所得を減らす）ため、すべての個人が同時に一定額の貯蓄をすることは不可能である（＝合成の誤謬）。その
ようにして消費を減らして貯蓄を増やそうとするあらゆる試みは、所得に影響を与えるので（＝所得を減らせてしまうので）、その試みは必然的に失敗する。も
ちろん社会全体が現在の投資量より少ない額の貯蓄（＝多くの消費）をすることも同様に不可能である。なぜなら、そのような試みは必然的に所得を増加させつ
づけて、個人が貯蓄しようとする額の総計が投資量とちょうど同じ数字になるレベルまで進むからである。
The above is closely analogous with the proposition which
harmonises the liberty, which every individual possesses, to change,
whenever he chooses, the amount of money he holds, with the necessity
for the total amount of money, which individual balances add up to, to
be exactly equal to the amount of cash which the banking system has
created. In this latter case the equality is brought about by the fact
that the amount of money which people choose to hold is not independent
of their incomes or of the prices of the things (primarily
securities有価証券、債券), the purchase of which is the natural alternative to
holding money. Thus incomes and such prices necessarily change until
the aggregate of the amounts of money which individuals choose to hold
at the new level of incomes and prices thus brought about has come to
equality with the amount of money created by the banking system. This,
indeed, is the fundamental proposition of monetary theory.
すべての個人は自分が保有（＝消費しない＝貯蓄）する貨幣量を好きなときに変更する自由をもっているが、その一方で、個々の収支を総計した全貨幣量は必然
的に銀行が創造した現金量（＝貨幣創造によって生まれた貨幣供給量）とちょうど一致する。前段の議論はこの自由と必然を調和させる命題と非常によく似てい
る。後者の場合にこの一致が生まれるのは、人々が保有しようとする貨幣量は、自分の所得や物品（主に債券）ー貨幣を保有し続けない場合に当然購入する物ー
の価格に制約されるという事実によるのである。つまり所得と債券価格は変化していって、それらが新たなレベルに達したとき個人が保有している貨幣量の総額
は必然的に最後には銀行が創造した貨幣量と等しくならざるを得ないのである。これは貨幣理論の根本命題である。
Both these propositions follow merely from the fact that there
cannot be a buyer without a seller or a seller without a buyer. Though
an individual whose transactions are small in relation to the market
can safely neglect the fact that demand is not a one-sided transaction,
it makes nonsense to neglect it when we come to aggregate demand. This
is the vital difference between the theory of the economic behaviour of
the aggregate and the theory of the behaviour of the individual unit,
in which we assume that changes in the individual's own demand do not
affect his income.
この二つの命題は単に「売り手がなければ買い手がない、買い手がなければ売り手がない」という事実から来ているに過ぎないのである。市場と比較して取引量
が少ない個人の場合には需要が一面的な取り引きではないという事実を無視しても問題はないが、総需要を扱うときにこの事実を無視するのはナンセンスであ
る。これが総額としての経済行動の理論と個人単位の行動の理論との決定的な違いである。個人の行動においては彼の需要の変化は彼の所得に影響を与えないと
見なせるのである。
Author's Footnotes
[1]. My method there was to regard the current realised profit as determining the current expectation of profit.
[2]. Vide Mr. Robertson's article “Saving and Hoarding” (Economic
Journal, September 1933, p. 399) and the discussion between Mr.
Robertson, Mr. Hawtrey and myself (Economic Journal, December 1933, p.
658).
[3]. Quarterly Journal of Economics, Nov. 1932, p. 123.
[4]. Loc. cit. p. 125.
著者注
[１] 『貨幣論』における私の方法は、当期に実現された利潤が当期の予想利潤を決定すると見なしている。
[２] ロバートソン氏の論文『貯蓄と貯蔵』（エコノミック・ジャーナル1933年9月399頁）と、私、ロバートソン氏そしてホートレー氏の間で行われた議論（エコノミック・ジャーナル1933年658頁）を見よ。
[３] 『クオーターリー・ジャーナル・オブ・エコノミスクス』（1932年11月123頁）
[４] 前掲書125頁。
Book III The Propensity to Consume
Chapter 8. The Propensity to Consume: I. The Objective Factors
第３巻 消費性向
第８章 消費性向 １ 客観的要因
I
WE are now in a position to return to our main theme, from which
we broke off at the end of Book I in order to deal with certain general
problems of method and definition. The ultimate object of our analysis
is to discover what determines the volume of employment. So far we have
established the preliminary conclusion that the volume of employment is
determined by the point of intersection of the aggregate supply
function with the aggregate demand function. The aggregate supply
function, however, which depends in the main on the physical conditions
of supply, involves few considerations which are not already familiar.
The form may be unfamiliar but the underlying factors are not new. We
shall return to the aggregate supply function in Chapter 20, where we
discuss its inverse under the name of the employment function. But, in
the main, it is the part played by the aggregate demand function which
has been overlooked; and it is to the aggregate demand function that we
shall devote Books III and IV.
第１節
方法と定義という一般的な問題を扱うために第一巻の終わりで中断していたメインテーマにここで戻ることにしよう。我々の分析の最終的な目的は雇用量を決め
るものは何かと決定することである。これまでのところでは、雇用量は総供給関数と総需要関数の交点で決まるという結論を我々は一応得ている。ところで、総
供給関数は主に物理的な供給条件によって決まるので、未知の検討課題はほとんど残っていない。関数の形式は珍しくても基本となる要素はよく知られているも
のばかりである（＝要素費用等々）。総供給関数については第２０章でその逆関数を雇用関数として再び扱うことになる。それに対して、総需要関数が果たす役
割はこれまであまり検討してこなかった。そこで、我々は第３巻と第４巻を総需要関数の検討に充てようと思う。
The aggregate demand function relates any given level of
employment to the “proceeds” which that level of employment is expected
to realise. The “proceeds” are made up of the sum of two quantities ―
the sum which will be spent on consumption when employment is at the
given level, and the sum which will be devoted to investment. The
factors which govern these two quantities are largely distinct（大きく異なる）.
In this book we shall consider the former, namely what factors
determine the sum which will be spent on consumption when employment is
at a given level; and in Book IV we shall proceed to the factors which
determine the sum which will be devoted to investment.
総需要関数はある雇用レベルとそれが実現すると予想される売上を結びつける関数である。その売上は二種類の金額の合計である。つまり、総需要関数とはその
雇用レベルにおける消費支出と投資支出の合計である。この二つの種類の金額を決める要素はそれぞれに異なっている。この巻では、ある雇用レベルにおける消
費支出の額を決める要因について考える。そのあと第４巻では投資支出の額を決める要因について考えることになる。
Since we are here concerned in determining what sum will be
spent on consumption when employment is at a given level, we should,
strictly speaking, consider the function which relates the former
quantity (C) to the latter (N). It is more convenient, however, to work
in terms of a slightly different function, namely, the function which
relates the consumption in terms of wage-units (Cw) to the income in
terms of wage-units (Yw) corresponding to a level of employment N.
我々がここで問題にしているのはある雇用レベルの時にどれだけの消費支出があるかなので、厳密に言えば、我々は消費量を雇用量に結びつける関数を考えるべ
きところである。しかしながら、少し異なる関数を扱うほうが都合が良い。それは雇用レベルの代わりにそれに対応する所得を考えて、ある雇用レベルＮの時に
単位賃金数で測った消費Ｃｗを単位賃金数で測った所得Ｙｗに結びつける関数である。
This suffers from the objection that Yw is not a unique function of N,
which is the same in all circumstances. For the relationship between Yw
and N may depend (though probably in a very minor degree) on the
precise nature of the employment. That is to say, two different
distributions of a given aggregate employment N between different
employments might (owing to the different shapes of the individual
employment functions ― a matter to be discussed in Chapter 20 below)
lead to different values of Yw. In conceivable
circumstances（ある場合には、そういう状況もある） a special allowance might have to be
made for this factor.
これには次のような反論が来るだろう。つまり、所得Ｙｗと雇用数Ｎの関係はたった一つではなく、状況によって大きく異なるはずだ、というものである。とい
うのは、所得Ｙｗと雇用数Ｎの関係は雇用の正確な性質に（多分ごく僅かな程度）依存するからである。つまり、ある総雇用Ｎを２つの異なる雇用に配分すると
（それぞれの雇用関数は異なってくる―これは第２０章で扱う）所得の値Ｙｗは異なってくる可能性があるからである。ある場合にはこの要因を特に考慮に入れ
る必要も出てくる。
But in general it is a good approximation to regard Yw as uniquely
determined by N. We will therefore define what we shall call the
propensity to consume as the functional relationship χ between Yw a
given level of income in terms of wage-units, and Cw the expenditure on
consumption out of that level of income, so that
Cw = χ(Yw) or C = W.χ(Yw).
しかし、一般的には所得Ｙｗは雇用数Ｎで一意的に決まってくると考えて概ね間違いない。したがって、我々が消費性向と呼ぶものは、単位賃金数で測った所得レベルＹｗとその所得レベルからの消費支出Ｃｗとの間の関数関係χと定義する。そこで、
Ｃｗ＝χ（Ｙｗ）あるいはＣ＝Ｗ×χ（Ｙｗ）
となる。
The amount that the community spends on consumption obviously
depends (i) partly on the amount of its income, (ii) partly on the
other objective attendant circumstances, and (iii) partly on the
subjective needs and the psychological propensities and habits of the
individuals composing it and the principles on which the income is
divided between them (which may suffer modification as output is
increased).
社会の消費支出量は（一）所得に一部は依存し、（ニ）他の客観的な付帯状況に一部は依存し、（三）社会を構成する個人の主観的な要求、心理的な傾向と習慣、個人間に所得を分配する原則（これは産出量の増加によって変化する）に一部は依存する。
The motives to spending interact and the attempt to classify them runs
the danger of false division. Nevertheless it will clear our minds to
consider them separately under two broad heads which we shall call the
subjective factors and the objective factors. The subjective factors,
which we shall consider in more detail in the next Chapter, include
those psychological characteristics of human nature and those social
practices and institutions which, though not unalterable, are unlikely
to undergo a material change over a short period of time except in
abnormal or revolutionary circumstances. In an historical enquiry or in
comparing one social system with another of a different type, it is
necessary to take account of the manner in which changes in the
subjective factors may affect the propensity to consume. But, in
general, we shall in what follows take the subjective factors as given;
and we shall assume that the propensity to consume depends only on
changes in the objective factors.
支出の様々な動機は互いに影響しあうし、その様々な動機を分類しようとすると、間違った分類をして恐れがある。それでも、それらを主観的要因と客観的要因
の二つに分けて考えることは頭の整理になるだろう。主観的要因については次章で詳しく検討するが、その中には人間の性質の心理的な性格と社会慣習と社会制
度が含まれる。それらは不変ではないとしても、異常な環境や革命的な状況でもなければ短期間で大きく変化をすることはない。歴史的に研究する場合や異なっ
た社会制度を比較研究する場合には、主観的要因の変化がどのように消費性向に影響を与えるかを検討する必要があるだろう。しかし、一般的に、以下において
は、主観的要因は所与のものとして取り扱うことにする。そして、消費性向は客観的な要因の変化だけに依存するものと想定する。
II
The principal objective factors which influence the propensity to consume appear to be the following:
(1) A change in the wage-unit. ― Consumption (C) is obviously much more
a function of (in some sense) real income than of money-income. In a
given state of technique and tastes and of social conditions
determining the distribution of income, a man's real income will rise
and fall with the amount of his command（支配、制御） over
labour-units（単位労働数）, i.e. with the amount of his income measured in
wage-units; though when the aggregate volume of output changes, his
real income will (owing to the operation of decreasing returns) rise
less than in proportion to his income measured in wage-units.
第２節
消費性向に影響を与える客観的な要因の主なものは次のとおりである。
（１）単位賃金（＝所得）の変化 ―
消費（Ｃ）は名目所得の関数と言うよりは明らかに（ある意味で）実質所得の関数である。技術と嗜好、それに所得の分配を決める社会的な条件が所与のものと
するとき、ある人の実質所得（＝製品の価格で測った所得＝製品の個数）は、彼が占める複数の単位労働数（＝何時間労働したか）、すなわち単位賃金数（＝例
えば時給×時間）で測った彼の所得（＝上記のＹｗ）に比例して上下する。ただし、総産出量が変化した時、（収穫逓減の法則のために）単位賃金数で測った所
得より実質所得は小さな割合で増えることになる（＝生産物の数は労働時間数より増え方が少ない）。
As a first approximation, therefore, we can reasonably assume that, if
the wage-unit changes, the expenditure on consumption corresponding to
a given level of employment will, like prices, change in the same
proportion; though in some circumstances we may have to make an
allowance for the possible reactions（反作用） on aggregate consumption of
the change in the distribution of a given real income between
entrepreneurs and rentiers resulting from a change in the wage-unit.
Apart from this, we have already allowed for changes in the wage-unit
by defining the propensity to consume in terms of income measured in
terms of wage-units.
したがって大雑把に言って、物価の変化と同じように、単位賃金が変化すると、ある雇用量に対応する消費支出も同じ割合で変化すると言ってよい。ただし、あ
る環境においては、単位賃金の変化は利子生活者と企業家の間の実質所得の配分に変化をもたらし、その変化が総消費に逆向きの作用を及ぼす可能性があること
を考慮する必要がある（＝既出「単位賃金の変化は貸手と借手の間に所得の再分配をもたらす」）。これ以外にも、我々は既に消費性向を単位賃金数で測った所
得によって定義した時に、単位賃金の変化を考慮に入れている。
(2) A change in the difference between income and net income. We have
shown above that the amount of consumption depends on net income rather
than on income, since it is, by definition, his net income that a man
has primarily in mind when he is deciding his scale of consumption. In
a given situation there may be a somewhat stable relationship between
the two, in the sense that there will be a function uniquely relating
different levels of income to the corresponding levels of net income.
If, however, this should not be the case, such part of any change in
income as is not reflected in net income must be neglected since it
will have no effect on consumption; and, similarly, a change in net
income, not reflected in income, must be allowed for. Save in
exceptional circumstances, however, I doubt the practical importance of
this factor. We will return to a fuller discussion of the effect on
consumption of the difference between income and net income in the
fourth section of this chapter.
（２）所得と純所得の差額（＝補足費用）の変化。上記で我々は消費量は所得ではなく純所得に依存することを示した。というのは、定義によって、人が消費の
規模を決めるときに第一に思い浮かべるのは自分の純所得であるからである。ある状況では所得と純所得の間には安定した関係が見られる場合がある。それは様
々なレベルの所得とそれに対応する純所得を一意的に結びつける関数が存在するという意味である。しかしながら、たとえそうでなくても、所得の変化のうちで
純所得に反映されない部分は無視しなければならない。なぜなら、その部分は消費に影響しないからである。また、同様に、所得に反映されない純所得の変化は
考慮に入れなければならない。しかしながら、例外的な環境を除いて、この要素の実際的な重要性に私は疑いを持っている。所得と純所得の差額が消費に与える
影響については、後にこの章の第四節でもっと詳しく議論する。
(3) Windfall changes in capital-values not allowed for in calculating
net income. ― These are of much more importance in modifying the
propensity to consume, since they will bear no stable or regular
relationship to the amount of income. The consumption of the
wealth-owning class may be extremely susceptible to unforeseen changes
in the money-value of its wealth. This should be classified amongst the
major factors capable of causing short-period changes in the propensity
to consume.
（３）純所得の計算には考慮されない資本価値の偶発的変化 ―
この変化は消費性向を変化させるうえでさらに重要である。というのは、この変化と所得量の間には安定した規則的関係はないからである。富裕階級の消費は彼
らの富がもつ貨幣価値の予測できない変化に極度に影響を受けやすい。この要素は消費性向に短期間に変化を引き起こす可能性があると考えるべきである。
(4) Changes in the rate of time-discounting, i.e. in the ratio of
exchange between present goods and future goods. ― This is not quite
the same thing as the rate of interest, since it allows for future
changes in the purchasing power of money in so far as these are
foreseen. Account has also to be taken of all kinds of risks, such as
the prospect of not living to enjoy the future goods or of confiscatory
taxation. As an approximation, however, we can identify this with the
rate of interest.
（４）期限割引率の変化。つまり、現在の財と将来の財の交換比率の変化。―
期限割引率は利子率と全く同じというわけではない。なぜなら、期限割引率の変化には、予想できるかぎりにおいて将来の貨幣の購買力の変化が含まれているか
らである。また将来の財を享受するまで生きていない可能性や重税が課される可能性など、あらゆるリスクも考慮されねばならない。しかし、大雑把に言えば。
これは利子率（＝利子率）を同じだと考えることが出来る。
The influence of this factor on the rate of spending out of a
given income is open to a good deal of doubt. For the classical theory
of the rate of interest,[1] which was based on the idea that the rate
of interest was the factor which brought the supply and demand for
savings into equilibrium, it was convenient to suppose that expenditure
on consumption is cet. par. negatively sensitive to changes in the rate
of interest, so that any rise in the rate of interest would appreciably
diminish consumption. It has long been recognised, however, that the
total effect of changes in the rate of interest on the readiness to
spend on present consumption is complex and uncertain, being dependent
on conflicting tendencies, since some of the subjective motives towards
saving will be more easily satisfied if the rate of interest rises,
whilst others will be weakened. Over a long period substantial changes
in the rate of interest probably tend to modify social habits
considerably, thus affecting the subjective propensity to spend ―
though in which direction it would be hard to say, except in the light
of actual experience.
所得からの支出量に対するこの要素の影響については大きな疑問の声があがっている。利子率についての古典派の理論は[１]、利子率が貯蓄の需要と供給を
均衡させる要因であるという考えに基いているので、その理論にとっては、消費支出は他の事情が同じならば利子率の変化には反比例して、利子率の上昇は消費
を下げると考えるのが好都合である。しかしながら、今期の消費支出に対する利子率の包括的な影響は、相反する傾向に依存しているので、複雑で不明確である
ということが、ずっと前から認識されてきている。というのは、利子率が上がっても、主観的な貯蓄の動機のうちには、容易に満たされるものもあれば弱められ
るものもあるからである。長期間の後には利子率の大きな変化が社会の習慣を大きく変えて、消費支出傾向にも影響を与える場合がある。ただし、どの方向に変
えるかは実際の経験に照らしてみなければ分からない。
The usual type of short-period fluctuation in the rate of interest is
not likely, however, to have much direct influence on spending either
way. There are not many people who will alter their way of living
because the rate of interest has fallen from 5 to 4 per cent, if their
aggregate income is the same as before. Indirectly there may be more
effects, though not all in the same direction. Perhaps the most
important influence, operating through changes in the rate of interest,
on the readiness to spend out of a given income, depends on the effect
of these changes on the appreciation or depreciation in the price of
securities and other assets. For if a man is enjoying a windfall
increment in the value of his capital, it is natural that his motives
towards current spending should be strengthened, even though in terms
of income his capital is worth no more than before; and weakened if he
is suffering capital losses. But this indirect influence we have
allowed for already under (3) above. Apart from this, the main
conclusion suggested by experience is, I think, that the short-period
influence of the rate of interest on individual spending out of a given
income is secondary and relatively unimportant, except, perhaps, where
unusually large changes are in question. When the rate of interest
falls very low indeed, the increase in the ratio between an annuity
purchasable for a given sum and the annual interest on that sum may,
however, provide an important source of negative saving by encouraging
the practice of providing for old age by the purchase of an annuity.
通常タイプの利子率の短期変動は支出に対して直接どの方向にも影響を与えることはない。総所得が同じなら利子率が５％から４％に下がったからと言って暮し
向きを変える人は多くない。間接的な影響はあるかもしれないが、同じ方向への影響とは限らない。利子率の変化が所得の支出に対して与える恐らく最も大きな
影響は、債券などの資産価格の高騰あるいは低下に対して利子率の変化がどのように影響するかで決まる。というのは、自分の資本の価値が偶発的に増加した場
合、たとえ所得としては自分の資本価値に変化がなくても、当期の支出の動機は強められるし、資本に損失が出たら支出の動機が弱まるのは当然である。しか
し、この間接的な影響は（３）で既に検討済みである。これを別としても経験が示唆する主な結論は、個人の所得の支出に対する利子率の短期の影響は、二次的
で比較的重要性を欠く。しかし、異常に大きな変化が起きた時はそうではない。実際、利子率が大きく下がった時には、ある金額で購入できる年金で毎年もらえ
る金額の方がその金額で稼げる毎年の利子よりも大きくなるので、老後に備えて年金を買うという習慣が促進されて、その結果、負の貯蓄（＝資産の取り崩し、
この場合は貯金の解約）がよく促進されるようになるかもしれない。
The abnormal situation, where the propensity to consume may be
sharply affected by the development of extreme uncertainty concerning
the future and what it（将来） may bring forth, should also, perhaps, be
classified under this heading.
消費性向が将来に対する大きな不安が広がることで急激な影響を受ける異常な状況は多分この括りに含まれる。
(5) Changes in fiscal policy. ― In so far as the inducement to the
individual to save depends on the future return which he expects, it
clearly depends not only on the rate of interest but on the fiscal
policy of the Government. Income taxes, especially when they
discriminate against “unearned” income, taxes on capital-profits,
death-duties and the like are as relevant as the rate of interest;
whilst the range of possible changes in fiscal policy may be greater,
in expectation at least, than for the rate of interest itself. If
fiscal policy is used as a deliberate instrument for the more equal
distribution of incomes, its effect in increasing the propensity to
consume is, of course, all the greater.[2]
（５）財政政策の変化 ―
個人の貯蓄性向を左右するものが予想される将来の利息である場合には、その性向は明らかに利子率だけでなく政府の財政政策にも影響を受ける。貯蓄性向に
とっては、所得税、特に不労所得にかかる所得税、資本利得税、相続税などは利子率と同じように重要である。その一方、財政政策の変化の幅、少なくともそれ
に対する期待の変化の幅は、利子率の変化の幅よりも大きい。もし所得の公平な配分のための意図的な道具として財政政策が使われるなら、消費性向を強める効
果はもちろん大きくなる[２]。
We must also take account of the effect on the aggregate propensity to
consume of Government sinking funds（減債基金、負債償却積立金） for the discharge of
debt（負債の返済） paid for out of ordinary taxation. For these represent a
species of corporate saving（法人貯蓄）, so that a policy of substantial
sinking funds must be regarded in given circumstances as reducing the
propensity to consume. It is for this reason that a change-over from a
policy of Government borrowing to the opposite policy of providing
sinking funds (or vice versa) is capable of causing a severe
contraction (or marked expansion) of effective demand.
通常の租税から支払われる公債償還のための減債基金が総消費性向に及ぼす効果も考慮されねばならない。なぜなら、減債基金というものは一種の法人貯蓄のよ
うな働きをするので、ある環境のもとでは巨大な減債基金の政策は消費性向を低下させると見做さねばならない。この理由のために、政府が借入れ政策から正反
対の減債基金を置く政策へ変更（あるいはその逆）すると有効需要の激しい縮小（あるいは明確な拡張）をもたらす可能性があるのである。
(6) Changes in expectations of the relation between the present and the
future level of income. ― We must catalogue this factor for the sake of
formal completeness. But, whilst it may affect considerably a
particular individual's propensity to consume, it is likely to average
out for the community as a whole. Moreover, it is a matter about which
there is, as a rule, too much uncertainty for it to exert much
influence.
（６） 現在の所得水準と将来の所得水準との間の関係についての予想の変化 ―
この要素をここに並べるのは形式的な完成度のためである。しかし、これは特定の個人の消費性向に大きく影響する一方で、社会全体としては平均化されるだろ
う。さらに、この問題が大きな影響力を持つためにはあまりにも不確実な要素が大きすぎる。
We are left therefore, with the conclusion that in a given
situation the propensity to consume may be considered a fairly stable
function, provided that we have eliminated changes in the wage-unit in
terms of money. Windfall changes in capital-values will be capable of
changing the propensity to consume, and substantial changes in the rate
of interest and in fiscal policy may make some difference; but the
other objective factors which might affect it, whilst they must not be
overlooked, are not likely to be important in ordinary circumstances.
したがって、貨幣で測った単位賃金の変化がないと仮定した場合、所与の状況では消費性向はかなり安定した関数であるという結論に至る。資本価値の偶発的変
化は消費性向を変化させる可能性があるし、利子率と財政政策の大きな変化はある程度の変化をもたらすだろう。しかし、消費性向に影響する他の客観的な要因
は、無視する訳にはいかないが、通常の環境においては重要ではない。
The fact that, given the general economic situation, the
expenditure on consumption in terms of the wage-unit depends in the
main[,] on the volume of output and employment is the justification for
summing up the other factors in the portmanteau（色んな性質を持った） function
“propensity to consume”. For whilst the other factors are capable of
varying (and this must not be forgotten), the aggregate income measured
in terms of the wage-unit is, as a rule, the principal variable upon
which the consumption-constituent of the aggregate demand function will
depend.
一般的な経済状況において、単位賃金で測った消費支出が主に産出量と雇用量に依存するという事実は、それ以外の要素は「消費性向関数」という色んな性質を
もつ関数の中に含めてもよいということを意味する。というのは、他の要素が変化するとしても（これは忘れてはいけない）、基本的には単位賃金で測った総所
得が主な変数であり、総需要関数のうちの消費はこの変数に依存するからである。
III
Granted（以上から仮に）, then, that the propensity to consume is a
fairly stable function so that, as a rule, the amount of aggregate
consumption mainly depends on the amount of aggregate income (both
measured in terms of wage-units), changes in the propensity itself
being treated as a secondary influence, what is the normal shape of
this function?
第３節
以上から、消費性向関数は変動の少ない関数であり、基本的には主に総所得量が総消費量（両者は単位賃金数で測ったものである）を決定し、消費性向自体の変
化がそこに脇から影響を与えると見なすならば、消費性向関数の標準的な形はどのようなものになるだろうか。
The fundamental psychological law, upon which we are entitled to
depend with great confidence both a priori from our knowledge of human
nature and from the detailed facts of experience, is that men are
disposed, as a rule and on the average, to increase their consumption
as their income increases, but not by as much as the increase in their
income. That is to say, if Cw is the amount of consumption and Yw is
income (both measured in wage-units) ΔCw has the same sign as ΔYw but
is smaller in amount, i.e. dCw/dYw is positive and less than unity.
人間の本質と経験的な事実から我々が大きな信頼を置ける基本的心理法則は、所得が増えれば消費も増えるが、消費の増加量は所得の増加量よりも小さいという
ことである。つまり、Ｃｗを消費量Ｙｗを所得とすると（両者とも単位賃金数で測った値）、ΔＣｗとΔＹｗは同じ符号をもっておりΔＣｗはΔＹｗよりも少な
い、即ちｄＣｗ／ｄＹｗは１より小さい正の数である。
This is especially the case where we have short periods in view,
as in the case of the so-called cyclical fluctuations of employment
<,>during which habits, as distinct from more permanent
psychological propensities, are not given time enough to adapt
themselves to changed objective circumstances. For a man's habitual
standard of life usually has the first claim on his income, and he is
apt to save the difference which discovers itself between his actual
income and the expense of his habitual standard; or, if he does adjust
his expenditure to changes in his income, he will over short periods do
so imperfectly. Thus a rising income will often be accompanied by
increased saving, and a falling income by decreased saving, on a
greater scale at first than subsequently.
これは短期を視野に考えるときに特に当てはまる。短期というのは例えば雇用の周期的は変動がそうである。それは客観情勢の変化に（もっと恒久的な心理的傾向とは違って）習慣的な事でさえも適応できないような期間である。というのは、人は普通自分の所得からまず第一に習慣的な生活レベルを維持するために支出する。そして、その生活水準を維持するための支出と自分の所得の差額を貯蓄に回すのである。あるいは、もし彼が自分の所得の変化に支出を適応させるとしても、短期間ではそれをうまく出来ないだろう。つまり、所得が上がると貯蓄も上がるだろうし、所得が減ると貯蓄も減るだろう（＝消費は変わらない）。しかも、その同調する規模は最初は大きく、後に小さくなっていくだろう。
But, apart from short-period changes in the level of income, it
is also obvious that a higher absolute level of income will tend, as a
rule, to widen the gap between income and consumption. For the
satisfaction of the immediate primary needs of a man and his family is
usually a stronger motive than the motives towards accumulation, which
only acquire effective sway when a margin of comfort has been attained.
These reasons will lead, as a rule, to a greater proportion of income
being saved as real income increases.
一方、所得レベルの短期の変化は別としても、所得レベルが絶対的に高くなると所得と消費の差が広がる傾向があるのも明らかである。というのは、普通は自
分と家族の今すぐの必要を満たす欲求のほうが貯蓄の欲求よりも強いものであり、ある程度楽な生活が出来るようになって初めて貯蓄の欲求が生まれるからであ
る。こういう次第で、所得が増えるに従ってより大きな所得の割合が貯蓄されるようになるのである。
But whether or not a greater proportion is saved, we take it as a
fundamental psychological rule of any modern community that, when its
real income is increased, it will not increase its consumption by an
equal absolute amount, so that a greater absolute amount must be saved,
unless a large and unusual change is occurring at the same time in
other factors.
その一方で、より大きな所得の割合が貯蓄されるか否かに関わらず、近代社会では実質所得が増えても、消費はそれと丁度同じ量だけ増えないのは、近代社会の
本質的な心理法則であって、その結果、他の要素に大きな変化がない限り、実質所得が増えると必ず貯蓄（＝消費しない分）の絶対量が増加するのである。
As we shall show subsequently,[3] the stability of the economic system
essentially depends on this rule prevailing in practice. This means
that, if employment and hence aggregate income increase, not all the
additional employment will be required to satisfy the needs of
additional consumption.
あとで示すように[３]、経済機構が安定していることは、本質的にはこの法則が現実に浸透しているおかげである。このことは、雇用とそれに伴う総所得が増
加した場合、増加した消費の需要を満たすためには、雇用の増加分の全てを振り向ける必要はないということを意味する（第３章第２節に既出）。
On the other hand, a decline in income due to a decline in the level of employment, if it goes far, may even cause consumption to exceed income not only by some individuals and institutions using up the financial reserves（個人貯蓄と法人貯蓄） which they have accumulated in better times, but also by the Government, which will be liable, willingly or unwillingly, to run into a budgetary deficit or will provide unemployment relief, for example, out of borrowed money.
他方、雇用レベルの低下のために所得が低下して、それが進んでいった場合には、消費が所得をオーバーしてしまうことも起こりうる（＝消費の低下は所得の低
下に同調しない）。それは、好調の時に蓄えた個人と機関の貯蓄でまかなわれる場合もあれば、政府によってまかなわれる場合もある。後者の場合は、好むと好まざるに関わらず、赤字予算となる。つまり、例えば失業率を下げるために借金をするのである。
Thus, when employment falls to a low level, aggregate consumption will decline by a smaller amount than that by which real income has declined, by reason both of the habitual behaviour of individuals and also of the probable policy of governments; which is the explanation why a new position of equilibrium can usually be reached within a modest range of fluctuation. Otherwise a fall in employment and income, once started, might proceed to extreme lengths.
つまり、雇用が低下して実質所得が低下しても、総消費はそれよりは少ない量しか減らないのである。それは個人の習慣的な行動様式（＝貯蓄）のためだけめなく、政府のありうべき政策（＝借金）のためである。このために、それほど大きな変動を経ずに新たな均衡に至るのである。さもなければ、雇用と所得の低下は一旦始まると極端な程度にまで進んでしまうだろう。
This simple principle leads, it will be seen, to the same
conclusion as before, namely, that employment can only increase pari
passu with an increase in investment; unless, indeed, there is a change
in the propensity to consume. For since consumers will spend less than
the increase in aggregate supply price when employment is increased,
the increased employment will prove unprofitable unless there is an
increase in investment to fill the gap.
この単純な原理のおかげで、他の条件が同じならば、雇用の増加は投資の増加と歩調を合わせるという、以前と同じ結論に至ることがわかるだろう。というの
は、雇用が増加した場合にも、消費支出は総供給価格（＝所得）よりも少いので、この２つの差を埋める投資の増加がなければ、雇用の増加は不利となるからで
ある。
IV
We must not underestimate the importance of the fact already
mentioned above that, whereas employment is a function of the expected
consumption and the expected investment, consumption is, cet.
par.(=ceteris paribus他の事情が同じならば), a function of net income, i.e. of net
investment (net income being equal to consumption plus net investment).
In other words, the larger the financial provision（金銭的な備え） which it is
thought necessary to make before reckoning net income, the less
favourable to consumption, and therefore to employment, will a given
level of investment prove to be.
第４節
雇用は消費と投資の予想値の関数であるが、その一方で、消費は他の事情が同じならば純所得の関数であり、それは即ち純投資の関数である（純所得は消費と純
投資の和に等しい）。この事実は既に述べたものだが（第３章２節（３）、第７章３節）、その重要性を決して軽視してはならない。言い換えれば、純所得を計
算する前に取りのけておく必要のある準備金が大きくなればなるだけ、投資が消費に与える効果も雇用に与える効果も小さくなってしまう。
When the whole of this financial provision (or supplementary
cost) is in fact currently expended in the upkeep of the already
existing capital equipment, this point is not likely to be overlooked.
But when the financial provision exceeds the actual expenditure on
current upkeep（維持）, the practical results of this in its effect on
employment are not always appreciated. For the amount of this excess
neither directly gives rise to current investment nor is available to
pay for consumption.
この準備金（つまり補足費用）が既存の資本設備の維持に全額支出されている間は、この問題は大したことではない。しかし、補足費用が当期の維持費を超えて
多すぎて余った場合に、それが現実の雇用に与える影響はしばしば見落とされてきた。というのは、この超過分は当期の投資を生み出すわけでもなく、消費に回
されることもないからである。
It has, therefore, to be balanced by new investment, the demand
for which has arisen quite independently of the current wastage of old
equipment <,>against which the financial provision is being made;
with the result that the new investment available to provide current
income is correspondingly diminished and a more intense demand for new
investment is necessary to make possible a given level of employment.
Moreover, much the same considerations apply to the allowance for
wastage included in user cost, in so far as the wastage is not actually
made good.
そのために、この余った分は新たな投資によって埋め合わせる必要がある。その新たな投資への需要は古い設備の消耗とは関係なく発生したものでなければなら
ない。その消耗に備えて補足費用が設定されているが、その結果、当期の所得をもたらすはずの新規投資はそれだけ減額されてしまっており、ある雇用レベルを
維持するためには、新規投資へのさらに大きな需要が必要となるのである。さらに、使用費用の中に含まれている消耗引当金についても、それが実際に出費され
ない場合には、まったく同じ懸念が当てはまる。
Take a house which continues to be habitable until it is
demolished or abandoned. If a certain sum is written off its value out
of the annual rent paid by the tenants, which the landlord neither
spends on upkeep（維持） nor regards as net income available for
consumption, this provision（準備金、蓄え）, whether it is a part of U or of V,
constitutes a drag（邪魔） on employment all through the life of the house,
suddenly made good in a lump（まとめて） when the house has to be rebuilt.
壊されるか廃棄されるまで住み続けられる家を考えてみよう。もし家賃収入の内から借家の価値を一定額ずつ取り除けていき、それを家主が借家の維持にも使わ
ず純所得として消費にも回さなかった場合には、この準備金は、∪の一部であろうと∨の一部であろうと、その家の寿命の続く限り雇用の妨げになり、家が建て
替えられる時に突然まとめて支出されるのである。
In a stationary economy all this might not be worth mentioning,
since in each year the depreciation allowances in respect of old houses
would be exactly offset by the new houses built in replacement of those
reaching the end of their lives in that year. But such factors may be
serious in a non-static economy, especially during a period which
immediately succeeds a lively burst of investment in long-lived
capital. For in such circumstances a very large proportion of the new
items of investment may be absorbed by the larger financial provisions
made by entrepreneurs in respect of existing capital equipment, upon
the repairs and renewal of which, though it is wearing out with time,
the date has not yet arrived for spending anything approaching the full
financial provision which is being set aside; with the result that
incomes cannot rise above a level which is low enough to correspond
with a low aggregate of net investment.
定常的な経済ではこうしたことの全ては言及する価値はないかもしれない。なぜなら、古い家の毎年の減価償却の引当金は、その年その年に寿命がつきた家が順
に新しい家に建て替えられることによって相殺されるからである。しかし、この要素は動的な経済では重要なものである。特に長い寿命をもつ資本に対して活発
な投資が行われた直後の期間はそうである。というのは、そのような状況では、新しい投資項目の大部分は、企業家たちが現在の投資設備のために設定したさら
に大きな準備金によって吸収されてしまうからである。その設備は時間とともに損耗するが、修理や買い替えのために設定された準備金の全額に近い額を使う期
日はまだ到来していないので、所得は低い純投資（Ａ１－Ｕ－Ｖ）の総額に対応する低いレベルを留まってしまう。
Thus sinking funds, etc., are apt to withdraw spending power from the
consumer long before the demand for expenditure on replacements (which
such provisions are anticipating) comes into play; i.e. they diminish
the current effective demand and only increase it in the year in which
the replacement is actually made. If the effect of this is aggravated
by “financial prudence”, i.e. by its being thought advisable to “write
off”（減価償却として取り除けておく） the initial cost（初期投資費用⇔維持管理費用ランニングコスト） more
rapidly than the equipment actually wears out, the cumulative result
may be very serious indeed.
つまり、減債基金等のおかげで（そのような準備金が予定している）買い替え需要が動き出すまでの長い間、消費者の支出力が取り上げられてしまう傾向がある
のである。このような準備金のおかげで当期の有効需要を減ってしまい、買い替えが実現する年になったようやく有効需要が増えるである。もしこの結果が「財
政的用心」つまり設備の消耗よりも先に初期投資費用を減価償却として取り除けておくことによってさらに悪化するなら、累積的な結果は非常に深刻なものとな
る。
In the United States, for example, by 1929 the rapid capital
expansion of the previous five years had led cumulatively to the
setting up of sinking funds and depreciation allowances, in respect of
plant which did not need replacement, on so huge a scale that an
enormous volume of entirely new investment was required merely to
absorb these financial provisions; and it became almost hopeless to
find still more new investment on a sufficient scale to provide for
such new saving as a wealthy community in full employment would be
disposed to set aside. This factor alone was probably sufficient to
cause a slump. And, furthermore, since “financial prudence” of this
kind continued to be exercised through the slump by those great
corporations which were still in a position to afford it, it offered a
serious obstacle to early recovery.
例えば、合衆国では１９２９年まではそれまでの５年間の急速な資本の拡張の結果、買い替えが必要でないプラントのために、減債基金と減価償却引当金が積立
てられて、それが非常に大規模だったので、これらの準備金を吸収するだけに新規の莫大な額の投資が必要となった。そして、完全雇用である豊かな社会が取り
除けておく新たな貯蓄に備えて、さらに大きな新投資を充分な規模で見つけるなど殆ど絶望的となったのである。この要因だけでも充分に景気後退の理由になっ
た。その上さらに、この種の「財政的用心」は不景気の間も余裕のある大企業によって実施され続けたために、早期の景気回復にとって大きな障害となったので
ある。
Or again, in Great Britain at the present time (1935) the
substantial amount of house-building and of other new investments since
the war has led to an amount of sinking funds being set up much in
excess of any present requirements for expenditure on repairs and
renewals, a tendency which has been accentuated, where the investment
has been made by local authorities and public boards, by the principles
of “sound” finance which often require sinking funds sufficient to
write off the initial cost some time before replacement will actually
fall due; with the result that even if private individuals were ready
to spend the whole of their net incomes it would be a severe task to
restore full employment in the face of this heavy volume of statutory
provision by public and semi-public authorities, entirely dissociated
from any corresponding new investment.
あるいはまた、英国では戦後家屋の建築など膨大な量の新たな投資が行われた結果、現在（１９３５年）では修理や買い替えに必要な額を超えた減債基金が設定
されている。この傾向は、投資が地方公共団体によって行われた場合には、買い替え時期が来る前に初期投資費用を減価償却として取り除けさせる「健全財政」
の方針によって強められた。その結果、個人が自分の純所得を全部支出しようとしても、公共機関と準公共機関による巨大な法定準備金を前に、それに対応する
新たな投資がまったく伴わない状態で完全雇用を回復するのは至難の業である。
The sinking funds of local authorities now stand, I think,[4] at an
annual figure of more than half the amount which these authorities are
spending on the whole of their new developments.[5] Yet it is not
certain that the Ministry of Health are aware, when they insist on
stiff sinking funds by local authorities, how much they may be
aggravating the problem of unemployment. In the case of advances by
Building Societies to help an individual to build his own house, the
desire to be clear of debt more rapidly than the house actually
deteriorates may stimulate the house-owner to save more than he
otherwise would; ― though this factor should be classified, perhaps, as
diminishing the propensity to consume directly rather than through its
effect on net income. In actual figures, repayments of mortgages
advanced by Building Societies, which amounted to ￡24,000,000 in 1925,
had risen to ￡68,000,000 by 1933, as compared with new advances of
￡103,000,000; and to-day the repayments are probably still higher.
地方公共団体の減債基金は今では毎年新たな開発に支出する全金額の半分以上[４]に達していると思われる[５]。しかし、健康省が地方団体に堅苦しい減債
基金を要求することで失業問題をどれほど悪化させているかを知っているのだろうか。建設協会が個人の住宅建設を援助する融資の場合は、家が劣化する前に借
金を返したいという欲求のおかげで、他の場合より家の持ち主の貯蓄欲が促進される。もっとも、この要因は消費性向を直接減少させるものであって、純所得へ
の効果を通じて消費性向を減らすものではない。実際の数字では建設協会からの借入金の返済額は１９２５年に２４００万ポンドだったものが、１９３３年には
新規の融資が１億３００万ポンドになったのに合わせて６８００万ポンドにまでのぼり、今日では恐らくそれ以上だろう。
That it is investment, rather than net investment, which emerges
from the statistics of output, is brought out forcibly and naturally in
Mr. Colin Clark's National Income, 1924-1931. He also shows what a
large proportion depreciation, etc., normally bears to the value of
investment. For example, he estimates that in Great Britain, over the
years 1928-1931,[6] the investment and the net investment were as
follows, though his gross investment is probably somewhat greater than
my investment, inasmuch as it may include a part of user cost, and it
is not clear how closely his “net investment” corresponds to my
definition of this term:
投入産出統計に現れている数字は純投資量ではなく粗投資量であることは、コーリン・クラーク氏の研究『１９２４から１９３１年の国民所得』が明らかにして
いる。また、同氏は粗投資量のどれだけ多くの部分を減価償却等が占めているかも示している。例えば、１９２８年から１９３１年[６]の英国の投資と純投資
を以下のように計算してる。ただし、彼の粗投資は使用費用を含んでいるので私の定義した投資より大きいし、彼の「純投資」は私の用語にどれだけ近いかは明
らかではない。
(￡ million)
1928 1929 1930
1931
Gross Investment-Output
791 731
620 482
“Value of physical wasting of old capital”
433 435
437 439
Net Investment
358 296
183 43
(１００万ポンド)
１９２８ １９２９ １９３０
１９３１
粗投入産出量
７９１ ７３１
６２０ ４８２
「旧資本の物的損耗値」
４３３ ４３５
４３７ ４３９
純投資
３５８ ２９６
１８３ ４３
Mr. Kuznets has arrived at much the same conclusion in compiling
the statistics of the Gross Capital Formation (as he calls what I call
investments) in the United States1919-1933. The physical fact（中身）, to
which the statistics of output correspond, is inevitably the gross, and
not the net, investment. Mr. Kuznets has also discovered the
difficulties in passing from gross investment to net investment. “The
difficulty”, he writes, “of passing from gross to net capital
formation, that is, the difficulty of correcting for the consumption of
existing durable commodities, is not only in the lack of data. The very
concept of annual consumption of commodities that last over a number of
years suffers from ambiguity”.[7] He falls back, therefore, “on the
assumption that the allowance for depreciation and depletion on the
books of business firms describes correctly the volume of consumption
of already existing' finished durable goods used by business firms”. On
the other hand, he attempts no deduction（償却費） at all in respect of
houses and other durable commodities in the hands of individuals. His
very interesting results for the United States can be summarised as
follows:
(Millions of Dollars)
1925 1926
1927 1928 1929
Gross capital formation
(after allowing for
net change in business
inventories)
30,706 33,571
31,157 33,934 34,491
Entrepreneurs' servicing,
repairs, maintenance,
depreciation and depletion
7,685 8,288 8,223
8,481 9,010
Net capital formation
(on Mr. Kuznets'definition)
23,021 25,293
22,934 25,453 25,481
(Millions of Dollars)
1930 1931
1932 1933
Gross capital formation
(after allowing for net
change in business
inventories)
27,538 19,721
7,780 14,879
Entrepreneurs' servicing,
repairs, maintenance,
depreciation and depletion 8,502 7,623 6,543 8,204
Net capital formation
(on Mr. Kuznets' definition) 19,036 11,098 1,237 6,675
クズネッツ氏も『合衆国の１９１９年から１９３３年の粗資本形成』（投資と私が呼ぶものを氏はこう呼ぶ）の統計でほぼ同じ結論に達している。この統計の数
字の実際の中身は当然純投資ではなく粗投資である。クズネッツ氏はまた粗投資から純投資を導き出すことが困難だと言っている。彼は「粗投資から純投資を導
き出すこと、つまり現存耐久財の消耗分を補正するのが難しいのは、データがないからだけではない。数年間にわたって継続する毎年の財の消耗という考え方は
非常に曖昧だからである」[７]と書いている。したがって、彼は「企業の帳簿の減価償却引当金と消耗引当金が現存耐久財の消耗量を正確に表していると想定
する」ことにした。一方、彼は個人所有の家屋や耐久財については償却費を差し引こうとしていない。合衆国について彼が行った興味深い計算結果は以下のよう
に要約できる。
(単位１００万ドル)
１９２５ １９２６
１９２７
１９２８ １９２９
粗資本形成
（企業在庫の純変化を勘案後） ３０,７０６
３３,５７１ ３１,１５７
３３,９３４ ３４,４９１
企業家の点検、補修、維持、
減価、損耗の償却費
７,６８５
８,２８８ ８,２２３ ８,４８１
９,０１０
純資本形成
（クズネッツ氏の定義による） ２３,０２１
２５,２９３ ２２,９３４
２５,４５３ ２５,４８１
（単位１００万ドル）
１９３０
１９３１
１９３２ １９３３
粗資本形成
（企業在庫の純変化を勘案後） ２７,５３８ １９,７２１ ７,７８０ １４,８７９
企業家の点検、補修、維持、
減価、損耗
の償却費
８,５０２ ７,６２３
６,５４３ ８,２０４
純資本形成
（クズネッツ氏の定義による） １９,０３６ １１,０９８ １,２３７ ６,６７５
Several facts emerge with prominence from this table. Net capital
formation was very steady over the quinquennium 1925-1929, with only a
10 per cent increase in the latter part of the upward movement. The
deduction for entrepreneurs' repairs, maintenance, depreciation and
depletion remained at a high figure even at the bottom of the slump.
But Mr. Kuznets' method must surely lead to too low an estimate of the
annual increase in depreciation, etc.; for he puts the latter at less
than 1 1/2 per cent per annum of the new net capital formation. Above
all, net capital formation suffered an appalling collapse after 1929,
falling in 1932 to a figure no less than 95 per cent below the average
of the quinquennium 1925-1929.
この表から色んな事が分かってくる。純資本形成は１９２５年から１９２９年までの５年間は安定しており、この上昇期の後半でもわずかに１０％増加しただけ
である。企業家の点検、補修、維持、減価、損耗などの償却費は不景気のどん底でも高いレベルを保っている。しかし、クズネッツ氏の方法では償却費の毎年の
増加は過剰に低く抑えられる。というのは、彼は償却費の毎年の増加を新たな純資本形成のうちの１.５％以下に設定しているからである。とにかく、純資本形
成は１９２９年が終わると崩壊して１９３２年の値は１９２５年から１９２９年の５年間の平均値の９５％も下回っている。
The above is, to some extent, a digression. But it is important
to emphasise the magnitude of the deduction which has to be made from
the income of a society, which already possesses a large stock of
capital, before we arrive at the net income which is ordinarily
available for consumption. For if we overlook this, we may
underestimate the heavy drag on the propensity to consume which exists
even in conditions where the public is ready to consume a very large
proportion of its net income.
以上は少々脱線である。しかし、大きな資本ストックをすでに持っている社会で、通常は消費に使える純所得を計算するまえに、所得から控除されるべき償却費
の大きさを強調しておくことは重要である。というのは、もしこの事実を見逃すと、社会が既に純所得のうちの非常に多くの部分を消費しようとしている状況に
おいて、なお消費性向を妨げる巨大なものが存在することを過小評価することになる。
Consumption ― to repeat the obvious ― is the sole end and object
of all economic activity. Opportunities for employment are necessarily
limited by the extent of aggregate demand. Aggregate demand can be
derived only from present consumption or from present provision for
future consumption. The consumption for which we can profitably provide
in advance cannot be pushed indefinitely into the future. We cannot, as
a community, provide for future consumption by financial expedients but
only by current physical output. In so far as our social and business
organisation separates financial provision for the future（準備金） from
physical provision for the future so that efforts to secure the former
do not necessarily carry the latter with them, financial prudence will
be liable to diminish aggregate demand and thus impair well-being, as
there are many examples to testify. The greater, moreover, the
consumption for which we have provided in advance, the more difficult
it is to find something further to provide for in advance, and the
greater our dependence on present consumption as a source of demand.
Yet the larger our incomes, the greater, unfortunately, is the margin
between our incomes and our consumption. So, failing some novel
expedient, there is, as we shall see, no answer to the riddle, except
that there must be sufficient unemployment to keep us so poor that our
consumption falls short of（不足する→所得から消費を引いたものが） our income by no more than the equivalent of
the physical provision for future consumption which it pays to produce to-day.
当たり前のことを繰り返すが、消費は全ての経済活動の唯一の目的であり目標である。雇用機会は総需要の大きさによって必然的に制約されるが、総需要をもた
らすのは現在の消費だけである。あるいはまた将来の消費に対して現在準備（＝機械の生産）することもそうであるが、それは将来有利になるように準備した消
費は永遠に引き伸ばすことは出来ないからである。社会として我々が将来の消費のために行える準備は金融的な手段（＝準備金）によってではなく現在の物理的
な産出（＝機械の生産）によってだけである。我々の社会やビジネス組織は将来への金融的な準備と物理的な準備を切り離したので、前者を確保する努力では必
ずしも同時に後者を確保できない。そういう状況では多くの例が証明するように、経済的用心深さは総需要を減らし社会の厚生を損ないがちである。さらに、将
来の消費への準備（＝機械の生産）が大きくなるほど、それ以上の将来のための準備を見つけることは難しいし、需要源としての現在の消費の役割は大きくな
る。しかし、不幸なことに、所得が大きくなるに連れて、所得と消費の差は大きくなる。だから、何か斬新な方法がないと、これから見るように、この問題に対
する答えはない。ただし、我々は大量に失業して非常な所得不足になれば、所得から現在の消費を引いたものが、今日生産する事が利益になる「将来の消費への
物理的準備」と全く等しくなるとだけは言える。
Or look at the matter thus. Consumption is satisfied partly by
objects produced currently and partly by objects produced previously,
i.e. by disinvestment. To the extent that consumption is satisfied by
the latter, there is a contraction of current demand, since to that
extent a part of current expenditure fails to find its way back as a
part of net income. Contrariwise whenever an object is produced within
the period with a view to satisfying consumption subsequently（後の、将来）,
an expansion of current demand is set up. Now all capital-investment is
destined to result, sooner or later, in capital-disinvestment.
しかし、それがだめならこういう見方もある。消費は今期の生産物と以前の生産物即ちマイナス投資（＝在庫の消耗）によって満たされる。消費が後者によっ
て満たされる分だけ、当期の需要は縮小する。なぜなら、その分だけ当期の支出は純所得に戻ってこないからである。逆にいえば、ある生産物が将来の消費を満
たすために今期内に作られるとき、今期の需要が拡張するのである。つまり、あらゆる資本投資は遅かれ早かれ資本のマイナス投資となる運命にあるのである。
Thus the problem of providing that new capital-investment shall always
outrun capital-disinvestment sufficiently to fill the gap between net
income and consumption, presents a problem which is increasingly
difficult as capital increases. New capital-investment can only take
place in excess of current capital-disinvestment if future expenditure
on consumption is expected to increase. Each time we secure to-day's
equilibrium by increased investment<,> we are aggravating the
difficulty of securing equilibrium to-morrow. A diminished propensity
to consume to-day can only be accommodated to the public advantage if
an increased propensity to consume is expected to exist some day. We
are reminded of “The Fable of the Bees” ― the gay of to-morrow are
absolutely indispensable to provide a raison d'e^tre for the grave of
to-day.
つまり、資本のマイナス投資を凌駕するような新たな資本投資によって、純所得と消費の差が広まるのを防ぐようにするという問題は、資本が増加するに従って
ますます困難となる。新たな資本投資が資本のマイナス投資を超えて行われるには、将来の消費支出が増加すると期待される時だけである。我々は今日の均衡を
手に入れるために投資を増やすたびに、明日の均衡を手に入れることを難しくしているのである。いつか消費性向が増加すると期待できないかぎり、今日減少し
た消費性向を社会の利益と調和させることはできない。我々は『蜂の寓話』（＝１８世紀にマンデヴィル作、節約を批判する内容、二三章七節で詳説）を思い出す。今日の憂鬱が存在理由を持つためには明日の陽気さが絶対に無くてはならないのだ。
It is a curious thing, worthy of mention, that the popular mind
seems only to be aware of this ultimate perplexity where public
investment is concerned, as in the case of road-building and
house-building and the like. It is commonly urged as an objection to
schemes for raising employment by investment under the auspices of
public authority that it is laying up trouble for the future. “What
will you do,” it is asked, “when you have built all the houses and
roads and town halls and electric grids and water supplies and so forth
which the stationary population of the future can be expected to
require?” But it is not so easily understood that the same difficulty
applies to private investment and to industrial expansion; particularly
to the latter, since it is much easier to see an early satiation of the
demand for new factories and plant which absorb individually but little
money, than of the demand for dwelling-houses.
奇妙なことだが、言っておくべき事は、道路建設や住宅建設などの公共投資に関するかぎり、人々の心はこの究極の難問に気づいているようである。一般的に、
公共機関の支援で行う投資による雇用増加計画は、将来の困難をためこむと反対される事が多い。「家と道路と公会堂と送電線と水道設備など将来の安定した人
口が必要とすると予想されるものを全部作ってしまったら、その後どうするつもりなのか？」と問われるのだ。しかし、この同じ困難が民間投資や産業の発展に
も当てはまることは、それほど容易には理解されない。特に後者にはこの問題がつきまとう。なぜなら、住宅の需要よりも、個別には殆どお金を吸収しない新たな工場やプラントの需要が早々に満たされるのは見易い事実だからである。
The obstacle to a clear understanding is, in these examples, much the
same as in many academic discussions of capital, namely, an inadequate
appreciation of the fact that capital is not a self-subsistent entity
existing apart from consumption. On the contrary, every weakening in
the propensity to consume regarded as a permanent habit must weaken the
demand for capital as well as the demand for consumption.
これらの例の理解を妨げているものは、資本に関する多くの学術的な理論の場合と同じである。それはすなわち、資本とは消費から切り離された自己完結的な存
在ではないという事実を充分に理解していないことである。それどころか、不変の習慣とみなされている消費性向が弱まるたびに、消費の需要だけではなく資本
の需要も必ず弱まるのである。
Author's Footnotes
[1]. Cf. Chapter 14 below.
[2]. It may be mentioned, in passing, that the effect of fiscal policy
on the growth of wealth has been the subject of an important
misunderstanding which, however, we cannot discuss adequately without
the assistance of the theory of the rate of interest to be given in
Book IV.
[3]. Cf. p. 251 below.
[4]. The actual figures are deemed of so little interest that they are only published two years or more in arrears.
[5]. In the year ending March 31, 1930, local authorities spent
￡87,000,000 on capital account, of which ￡37,000,000 was provided by
sinking funds, etc., in respect of previous capital expenditure; in the
year ending March 31, 1933, the figures were ￡81,000,000 and
￡46,000,000.
[6]. Op. cit. pp. 117 and 138.
[６] 前掲書 １１７頁と１３８頁。
[7]. These references are taken from a Bulletin (No. 52) of the
National Bureau of Economic Research, giving preliminary results of Mr.
Kuznets' forthcoming book.
著者注
[１] １４章参照。
[２] 序でに言っておくと、富の増加に対する財政政策の影響は重要な誤解のテーマとなってきたが、第４巻で扱う利子率の理論の助けなしには充分に論じることはできない。
[３] ２５１頁参照。
[４] 実際の数字は重視されていないので２年以上遅れて公開されている。
[５] １９３０年３月３１日で終わる年度に、地方公共団体は８千７百万ドルを資本勘定で支出しているが、そのうちの３千７百万ドルは以前の資本支出に対
する減債基金等によって拠出されている。１９３３年３月３１日で終わる年度には、その数字は８千１百万ドルと４千６百万ドルである。
[７] この言葉はクズネッツ氏の近刊書の予備的結果を掲載している全米経済研究所の紀要５２号からとった。
Chapter 9. The Propensity to Consume: II. The Subjective Factors
第９章 消費性向 ２ 主観的な要因
I
THERE remains the second category of factors which affect the
amount of consumption out of a given income, namely, those subjective
and social incentives which determine how much is spent, given the
aggregate of income in terms of wage-units and given the relevant
objective factors which we have already discussed. Since, however, the
analysis of these factors raises no point of novelty, it may be
sufficient if we give a catalogue of the more important, without
enlarging on them at any length.
第１節
消費の所得に占める量に影響する要因の二つ目のカテゴリーは、どれだけ消費するかを決める主観的で社会的な動機である。その際、単位賃金数で測った総所得
と既に述べたこれに関連する客観的な要因は所与のものとする。しかし、主観的要素の分析には新しい論点はないので、その中でも比較的重要なものを並べて簡
単な説明を加えれば充分だろう。
There are, in general, eight main motives or objects of a
subjective character which lead individuals to refrain from spending
out of their incomes:
(i) To build up a reserve against unforeseen contingencies;
(ii) To provide for an anticipated future relation between the income
and the needs of the individual or his family different from that which
exists in the present, as, for example, in relation to old age, family
education, or the maintenance of dependents;
(iii) To enjoy interest and appreciation, i.e. because a larger real
consumption at a later date is preferred to a smaller immediate
consumption;
(iv) To enjoy a gradually increasing expenditure, since it gratifies a
common instinct to look forward to a gradually improving standard of
life rather than the contrary, even though the capacity for enjoyment
may be diminishing;
(v) To enjoy a sense of independence and the power to do things, though
without a clear idea or definite intention of specific action;
(vi) To secure a masse de manoeuvre（仏、予備金） to carry out speculative or business projects;
(vii) To bequeath a fortune;
(viii) To satisfy pure miserliness, i.e. unreasonable but insistent inhibitions against acts of expenditure as such.
人が自分の所得からの出費を控える主観的な目的ないし動機は主に八つある。
（一）不測の事態に備えるため。
（二）現在とは異なる将来の予想される所得と出費の関係に備えるため。例えば、老後の生活、家族の教育、扶養家族の生活など、家族や個人の将来の必要に備える。
（三）利子や価値の上昇を楽しむため。なぜなら、少額の消費をすぐにするより実質的に高額な消費をあとでするほうが望ましいから。
（四）支出が次第に増えることを楽しむため。なぜなら、楽しみは次第に減っていくにもかかわらず、生活水準が次第に向上することへの期待は誰の本能も満足することだから。
（五）何か具体的にしようという計画はなくても、自律感と有能感を得るため。
（六）投機的あるいは経営上の企画を実行するための大量の運用資金を確保するため。
（七）財産を遺すため。
（八）純粋な貪欲を満たすため。消費支出そのものに反対する不合理な抑制心。
These eight motives might be called the motives of Precaution,
Foresight, Calculation, Improvement, Independence, Enterprise, Pride
and Avarice; and we could also draw up a corresponding list of motives
to consumption such as Enjoyment, Short-sightedness, Generosity,
Miscalculation, Ostentation and Extravagance.
消費を控えるこれら八つの動機は、用心、深慮、打算、向上、独立、企業、自尊、貪欲と呼ぶことが出来る。これに対して、消費を行う動機は、享楽、浅慮、寛大、誤算、虚飾、浪費である。
Apart from the savings accumulated by individuals, there is also
the large amount of income, varying perhaps from one-third to
two-thirds of the total accumulation in a modern industrial community
such as Great Britain or the United States, which is withheld by
Central and Local Government, by Institutions and by Business
Corporations ― for motives largely analogous to, but not identical
with, those actuating individuals, and mainly the four following:
(i) The motive of enterprise ― to secure resources to carry out further
capital investment without incurring debt or raising further capital on
the market;
(ii) The motive of liquidity ― to secure liquid resources to meet emergencies, difficulties and depressions;
(iii) The motive of improvement ― to secure a gradually increasing
income, which, incidentally, will protect the management from
criticism, since increasing income due to accumulation is seldom
distinguished from increasing income due to efficiency;
(iv) The motive of financial prudence and the anxiety to be “on the
right side” by making a financial provision in excess of user and
supplementary cost, so as to discharge debt and write off the cost of
assets ahead of, rather than behind, the actual rate of wastage and
obsolescence, the strength of this motive mainly depending on the
quantity and character of the capital equipment and the rate of
technical change.
個人が蓄える貯蓄のほかに、英国や米国のような近代産業社会では、中央政府と地方政府、民間機関や営利企業によって大量の所得が保持されている。これは個
人の蓄えを含めた全ての蓄えの３分の１から３分の２に達する。この蓄えを動機は個人の場合と全く同じではないが類似の動機に基づいている。
（一）企業的動機―市場で資本を調達せず借金もせずに投資を増やす資金を確保するため。
（二）流動性（＝初出、現金および換金可能性の高いこと）の動機―緊急事態や困難や不況に備えて流動性資産を確保するため。
（三）改良の動機―所得を次第に増加させるため。ちなみに、所得の増加は蓄えに依る場合も効率化による場合も区別できないので、経営を批判から守ることができる。
（四）財政的な慎重さと、使用費用と補足費用以上の金銭的な蓄えをすることで「黒字経営」を維持しようとする願い。これは負債を支払い、資産の損耗や旧式
化の速度に遅れないように、むしろ先立って費用を償却するためである。この動機の強さは主に資産設備の量と性格、および技術的な変化のレベルに依存する。
Corresponding to these motives which favour the withholding of a
part of income from consumption, there are also operative at times
motives which lead to an excess of consumption over income. Several of
the motives towards positive saving catalogued above as affecting
individuals have their intended counterpart in negative saving at a
later date, as, for example, with saving to provide for family needs or
old age. Unemployment relief financed by borrowing is best regarded as
negative saving.
所得の一部の消費を控えるこれらの動機に対応して、時にはまた所得を超えた消費をする動機が存在する。上記に列挙した動機の多くは個人の場合にはプラスの
貯蓄を促すものであるが、例えば家族の必要や老後のための貯蓄の場合には、それが後になってマイナスの貯蓄を促す動機ともなる。失業対策を借入金で賄え
ば、それはマイナス貯蓄と見なすのがよい。
Now the strength of all these motives will vary enormously
according to the institutions and organisation of the economic society
which we presume, according to habits formed by race, education,
convention, religion and current morals, according to present hopes and
past experience, according to the scale and technique of capital
equipment, and according to the prevailing distribution of wealth and
the established standards of life. In the argument of this book,
however, we shall not concern ourselves, except in occasional
digressions, with the results of far-reaching social changes or with
the slow effects of secular progress. We shall, that is to say, take as
given the main background of subjective motives to saving and to
consumption respectively. In so far as the distribution of wealth is
determined by the more or less permanent social structure of the
community, this also can be reckoned a factor, subject only to slow
change and over a long period, which we can take as given in our
present context.
これら全ての動機の強さは、我々が想定する経済社会の機関や組織によって、民族・教育・慣習・宗教・道徳が形成した習慣によって、現在の希望と過去の経験
によって、資本設備の規模と技術によって、支配的な富の分配の仕方と一般的な生活水準によって、大きく変化する。しかし、本書では、時々脱線するときのほ
かは、社会的な変化の先々の効果や、長年に渡る進歩の遅れた効果については扱わない。つまり、貯蓄と消費のそれぞれについての主観的な動機の主要な背景は
所与のものとして扱うのである。ある程度恒久的な社会構造によって決まっている富の分配については、変化が遅く長期間にわたるものなので、これもまた我々
の文脈では所与の要因と見なすことが出来る。
II
Since, therefore, the main background of subjective and social
incentives changes slowly, whilst the short-period influence of changes
in the rate of interest and the other objective factors is often of
secondary importance, we are left with the conclusion that short-period
changes in consumption largely depend on changes in the rate at which
income (measured in wage-units) is being earned and not on changes in
the propensity to consume out of a given income.
第２節
したがって、主観的かつ社会的インセンティブの変化はゆっくりしており、その一方で、利子率や他の客観的要因の変化の短期的影響はあまり重要ではないの
で、短期における消費の変化が依存するのは主に所得（単位賃金数で測った）の量の変化であって、所得に対する消費性向の変化ではないという結論に至らざる
を得ない。
We must, however, guard against a misunderstanding. The above
means that the influence of moderate changes in the rate of interest on
the propensity to consume is usually small. It does not mean that
changes in the rate of interest have only a small influence on the
amounts actually saved and consumed. Quite the contrary. The influence
of changes in the rate of interest on the amount actually saved is of
paramount importance, but is in the opposite direction to that usually
supposed. For even if the attraction of the larger future income to be
earned from a higher rate of interest has the effect of diminishing the
propensity to consume, nevertheless we can be certain that a rise in
the rate of interest will have the effect of reducing the amount
actually saved.
しかし、ここで誤解をしてはいけない。上記の意味は、利子率の穏やかな変化が消費性向に与える影響は普通は小さいということであって、実際に貯蓄される額
と消費される額への利子率の変化の影響が小さいということではない。逆である。実際の貯蓄高への利子率の変化の影響は極めて大きいのであるが、それは普通
に考えられているのと正反対なのである。とうのは、たとえ高い利子率から得られる将来の大きな所得の魅力が消費性向を下げる効果があるとしても、それにも
かかわらず、利子率の上昇は実際の貯蓄高を減らす効果があるのである。
For aggregate saving is governed by aggregate investment; a rise in the
rate of interest (unless it is offset by a corresponding change in the
demand-schedule for investment) will diminish investment; hence a rise
in the rate of interest must have the effect of reducing incomes to a
level at which saving is decreased in the same measure as investment.
Since incomes will decrease by a greater absolute amount than
investment, it is, indeed, true that, when the rate of interest rises,
the rate of consumption will decrease. But this does not mean that
there will be a wider margin for saving. On the contrary, saving and
spending will both decrease.
というのは、総貯蓄は総投資次第だからである。利子率の上昇は（それに対応する投資需要表の変化によって相殺されない限りは）投資を減らす。ということ
は、利子率の上昇は所得を減らして、投資が減るのと同じだけ貯蓄も減るということである。所得は投資より絶対量で大きく減少するので、確かに、利子率が上
昇すれば、消費が減る。しかし、これは貯蓄の余地が広がるという意味ではない。貯蓄と消費が両方とも減るのである。
Thus, even if it is the case that a rise in the rate of interest
would cause the community to save more out of a given income, we can be
quite sure that a rise in the rate of interest (assuming no favourable
change in the demand-schedule for investment) will decrease the actual
aggregate of savings. The same line of argument can even tell us by how
much a rise in the rate of interest will, cet. par., decrease incomes.
For incomes will have to fall (or be redistributed) by just that amount
which is required, with the existing propensity to consume, to decrease
savings by the same amount by which the rise in the rate of interest
will, with the existing marginal efficiency of capital, decrease
investment. A detailed examination of this aspect will occupy our next
chapter.
つまり、利子率の上昇によって社会が所得の中からより多く貯蓄しようとするのが事実だとしても、（投資需要表の有利な変化がないとすると）利子率の上昇に
よって実際の総貯蓄が減るのは確実なのである。同様に考えていくと、他の条件が同じなら、利子率の上昇によって所得がどれだけ減るかも分かるのである。と
いうのは、現行の資本の限界効率のもとで、利子率の上昇によって投資が減るが、それは貯蓄が減る量と同じであり、現状の消費性向のもとで、それだけ貯蓄が
減るためには、ちょうどその量だけ所得が減らなければ（再配分されなければ）ならないからである。この点の詳しい検証は次の章で行われる。
The rise in the rate of interest might induce us to save more, if our
incomes were unchanged. But if the higher rate of interest retards
investment, our incomes will not, and cannot, be unchanged. They must
necessarily fall, until the declining capacity to save has sufficiently
offset the stimulus to save given by the higher rate of interest. The
more virtuous we are, the more determinedly thrifty, the more
obstinately orthodox in our national and personal finance, the more our
incomes will have to fall when interest rises relatively to the
marginal efficiency of capital. Obstinacy can bring only a penalty and
no reward. For the result is inevitable.
もし我々の所得に変化がなければ、利子率の上昇によって貯蓄を増やしたい気になるかもしれない。しかし、もし高い利子率によって投資が抑制されると、我々
の所得は不変ではないし、不変ではありえない。所得は必ず減って行き、貯蓄する力が落ちて高い利子率に刺激された貯蓄欲がなくなるのである。我々がみな道
徳的であり、倹約家であり、国の財政と家計に関して頑固な正統派であるなら、利子率が資本の限界効率（＝予想収益率）よりも上昇したときには（＝投資が減
るから）我々の所得は減らざるをえないのである。頑固さには何の報酬もない。ただ罰を受けるだけである。なぜなら、結果は避けられないからである。
Thus, after all, the actual rates of aggregate saving and spending do
not depend on Precaution, Foresight, Calculation, Improvement,
Independence, Enterprise, Pride or Avarice. Virtue and vice play no
part. It all depends on how far the rate of interest is favourable to
investment, after taking account of the marginal efficiency of
capital[1]. No, this is an overstatement. If the rate of interest were
so governed as to maintain continuous full employment, Virtue would
resume her sway; ― the rate of capital accumulation would depend on the
weakness of the propensity to consume. Thus, once again, the tribute
that classical economists pay to her is due to their concealed
assumption that the rate of interest always is so governed.
つまり、結局のところ、実際の貯蓄量と消費量は、用心、深慮、打算、向上、独立、企業心、自尊、貪欲とは関係がないのである。道徳も悪徳も何も関係がな
い。その全ては、資本の限界効率[１]との比較の上で、利子率が投資にとってどれほど有利な値であるかにかかっているのだ。いや、これは言いすぎだ。もし
完全雇用が維持されるように利子率がコントロールされているなら、道徳が支配権を取り戻して、資本の蓄積額は消費性向の弱さ（＝節約は美徳）に依存するよ
うになるだろう。つまり、もう一度繰り返すと、古典派経済学者たちは、完全雇用を維持するように利子率がコントロールされていると無意識のうちに想定して
いるからこそ、道徳を讃えるのである。
Author's Footnotes
[1]. In some passages of this section we have tacitly anticipated ideas which will be introduced in Book IV.
著者注
[１]この節の中のいくつかの文章には第４巻に出てくる考え方がそれとなく先取りされている。
Chapter 10. The Marginal Propensity to Consume and the Multiplier
第１０章 限界消費性向と乗数
WE established in Chapter 8 that employment can only increase pari
passu with investment. We can now carry this line of thought a stage
further.
第８章において我々は、他の条件が同じならば、雇用は投資と歩調をあわせて増加することを確認した。今や我々はこの考えをさらに進めていくことができる。
For in given circumstances a definite ratio, to be called the
Multiplier（乗数）, can be established between income and investment and,
subject to certain simplifications, between the total employment and
the employment directly employed on investment (which we shall call the
primary employment). This further step is an integral part of our
theory of employment, since it establishes a precise relationship,
given the propensity to consume, between aggregate employment and
income and the rate of investment.
というのは、一定の環境においては、「乗数」という名の明確な比率が、所得と投資の間に、そしてある種の単純化を経ることによって、総雇用と投資による直
接雇用（これを我々は一次雇用と呼ぶ）の間に確立できるからである。この段階こそは我々の雇用の理論の中心となる部分となる。なぜなら、ここで我々は、一
定の消費性向のもとで、総雇用と所得と投資量の間に正確な関係を確立するからである。
The conception of the multiplier was first introduced into economic
theory by Mr. R. F. Kahn in his article on “The Relation of Home
Investment to Unemployment” (Economic Journal, June 1931). His argument
in this article depended on the fundamental notion that, if the
propensity to consume in various hypothetical circumstances is
(together with certain other conditions) taken as given and we conceive
the monetary or other public authority to take steps to stimulate or to
retard investment, the change in the amount of employment will be a
function of the net change in the amount of investment; and it aimed at
laying down general principles by which to estimate the actual
quantitative relationship between an increment of net investment and
the increment of aggregate employment which will be associated with it.
Before coming to the multiplier, however, it will be convenient to
introduce the conception of the marginal propensity to consume.
乗数概念はＲ．Ｆ．カーン氏が「国内投資と失業の関係」（エコノミック・ジャーナル誌１９３１年６月号）において経済理論に最初に導入したものである。こ
の論文の中心となる考え方は、多様な仮定的環境のもとで（他の条件も含めて）消費性向を所与のものとして、金融当局などの公共組織が投資を刺激したり鈍ら
せたりする手段を取るとき、雇用量の変化は純投資量の変化の関数であるというものである。それは純投資の増加とそれに伴う総雇用の増加の間の実際の量的関
係を測定する一般的な原理を打ち立てることを目指すものである。しかしながら、乗数概念の話に行く前に、限界消費性向という考え方を導入しておくのが便利
だろう。
I
The fluctuations in real income under consideration in this book
are those which result from applying different quantities of employment
(i.e. of labour-units) to a given capital equipment, so that real
income increases and decreases with the number of labour-units
employed. If, as we assume in general, there is a decreasing return at
the margin as the number of labour-units employed on the given capital
equipment is increased, income measured in terms of wage-units will
increase more than in proportion to the amount of employment, which, in
turn, will increase more than in proportion to the amount of real
income measured (if that is possible) in terms of product.
第１節
本書で考えられている実質所得の変動は、資本設備に様々な雇用量（つまり単位労働数）を適用した結果であり、雇用された単位労働数によって実質所得は増減
するのである。もし普通に考えられるように、資本施設に雇用される単位労働数が増えるにしたがって限界収益が逓減するなら、単位賃金数で測った所得（＝利
潤込みの労働時間数）が雇用量（＝賃金の労働時間数）より大きな割合で増えて、次に、雇用量が（可能なら）生産物で測った実質所得（＝生産数）より大きな
割合で増えるだろう（＝『コンメンタールｐ９６に逆の順で同様の記述。第８章第２節にも既出）。
Real income measured in terms of product and income measured in terms
of wage-units will, however, increase and decrease together (in the
short period when capital equipment is virtually unchanged). Since,
therefore, real income, in terms of product, may be incapable of
precise numerical measurement, it is often convenient to regard income
in terms of wage-units (Yw) as an adequate working index of changes in
real income. In certain contexts we must not overlook the fact that, in
general, Yw increases and decreases in a greater proportion than real
income; but in other contexts the fact that they always increase and
decrease together renders them virtually interchangeable.
しかしながら、生産物で測った実質所得と単位賃金数で測った所得は一緒に増減する（資本設備が不変である短期の場合）。そこで、生産物で測った実質所得は
正確な数字では表せないので、単位賃金数で測った所得（Ｙｗ）を実質所得の変化の有効な指標として使うのが便利である。確かに、一般的に、Ｙｗは実質所得
より大きな割合で増減することを見逃すべきではない場合がある。しかし、それ以外の場合には、この２つが一緒に増減することから、この２つは実質的に代替
可能なのである。
Our normal psychological law that, when the real income of the
community increases or decreases, its consumption will increase or
decrease but not so fast, can, therefore, be translated ― not, indeed,
with absolute accuracy but subject to qualifications which are obvious
and can easily be stated in a formally complete fashion ― into the
propositions that ΔCw and ΔYw have the same sign, but ΔYw > ΔCw,
where Cw is the consumption in terms of wage-units. This is merely a
repetition of the proposition already established on p. 29 above.
社会の実質所得が増減する時それに応じた社会の消費の増減幅はそれより少ないというのが我々の通常の心理法則だが、それはΔＣｗとΔＹｗは同じ符号を持っ
ておりΔＹｗ＞ΔＣｗ（Ｃｗは単位賃金数で測った消費量）であるという命題に翻訳できる（この翻訳には完璧な正確さはなく、形式的に完全な形で容易に表わ
される明確な条件が付く）。これは上記２９頁（＝三章二節（８））で既に確認した命題の繰り返しである。
Let us define, then, dCw/dYw as the marginal propensity to consume.
This quantity is of considerable importance, because it tells us how
the next increment of output will have to be divided between
consumption and investment. For ΔYw = ΔCw + ΔIw, where ΔCw and ΔIw are
the increments of consumption and investment; so that we can write ΔYw
= kΔIw, where 1 - (1/k) is equal to the marginal propensity to consume.
Let us call k the investment multiplier. It tells us that, when there
is an increment of aggregate investment, income will increase by an
amount which is k times the increment of investment.
そこで、ｄＣｗ／ｄＹｗを「限界消費性向」と定義しよう。
この量はとても重要である。なぜなら、この量は産出物の次の増加がどのように消費と投資に分割されるかを教えているからである。というのは、ΔＹｗ＝
ΔＣｗ＋ΔIｗ（ΔＣｗとΔＩｗは消費と投資の増加）だからである。そこで、ΔＹｗ＝ｋΔＩｗと表すと、１－（１／ｋ）は限界消費性向に等しい（←１ー
ΔIｗ／ΔＹｗ＝ΔＣｗ／ΔＹｗ）。
このｋを投資乗数と呼ぼう。それは総投資が増加したとき、所得は投資の増加のｋ倍だけ増えるという意味である。
II
Mr. Kahn's multiplier is a little different from this, being
what we may call the employment multiplier designated by k', since it
measures the ratio of the increment of total employment which is
associated with a given increment of primary employment in the
investment industries. That is to say, if the increment of investment
ΔIw leads to an increment of primary employment ΔN2 in the investment
industries, the increment of total employment ΔN = k'ΔN2.
第２節
カーン氏の乗数はこれとは若干異なっており、彼の乗数は雇用乗数と呼べるもので、それはｋ'で表わすことができる。というのは、彼の乗数は、投資産業にお
ける一次雇用の増加とそれに伴う総雇用の増加の割合を示しているからである。つまり、もし投資の増加ΔＩｗが投資産業に一次雇用の増加ΔＮ２をもたらすな
ら、総雇用の増加ΔＮはｋ'×ΔＮ２と等しくなる。
There is no reason in general to suppose that k = k'. For there is no
necessary presumption that the shapes of the relevant portions of the
aggregate supply functions for different types of industry are such
that the ratio of the increment of employment in the one set of
industries to the increment of demand which has stimulated it will be
the same as in the other set of industries.[1] It is easy, indeed, to
conceive of cases, as, for example, where the marginal propensity to
consume is widely different from the average propensity, in which there
would be a presumption <in favour of some inequality between>
ΔYw/ΔN and ΔIw/ΔN2, since there would be very divergent proportionate
changes in the demands for consumption-goods and investment-goods
respectively.
一般にｋ＝ｋ'であると考える理由はない。というのは、異なる産業に関連する部分の総供給関数の形状が同じで、ある産業部門の雇用の増加とその増加を刺激
した需要の増加の比率が、他の産業部門と同じとなると想定する必要はないからである[１]
。確かに、例えば、限界消費性向が平均消費性向と大きく異なっていて、消費財の需要と投資財の需要の変化率が非常に違っているので、ΔＹｗ／ΔＮと
ΔＩｗ／ΔＮ２が一致しない場合を想像することは容易い（？）。
If we wish to take account of such possible differences in the
shapes of the relevant portions of the aggregate supply functions for
the two groups of industries respectively, there is no difficulty in
rewriting the following argument in the more generalised form. But to
elucidate the ideas involved, it will be convenient to deal with the
simplified case where k = k'.
もし総供給関数の中の二つの産業部門に関連する部分の形状がそれほど異なっているという可能性を考慮に入れたければ、以下の議論をもっと一般的な形で書き
換えることは難しいことではない。しかし、そこに含まれている考え方を明らかにするには、ｋ＝ｋ'である単純化した場合を扱うのが便利である。
It follows, therefore, that, if the consumption psychology of
the community is such that they will choose to consume, e.g.,
nine-tenths of an increment of income,[2] then the multiplier k is 10;
and the total employment caused by (e.g.) increased public works will
be ten times the primary employment provided by the public works
themselves, assuming no reduction of investment in other directions.
Only in the event of the community maintaining their consumption
unchanged in spite of the increase in employment and hence in real
income, will the increase of employment be restricted to the primary
employment provided by the public works. If, on the other hand, they
seek to consume the whole of any increment of income, there will be no
point of stability and prices will rise without limit. With normal
psychological suppositions, an increase in employment will only be
associated with a decline in consumption if there is at the same time a
change in the propensity to consume ― as the result, for instance, of
propaganda in time of war in favour of restricting individual
consumption; and it is only in this event that the increased employment
in investment will be associated with an unfavourable repercussion on
employment in the industries producing for consumption.
したがって、もし社会の消費心理が所得の増加の例えば１０分の９を消費するつもりなら[２]、乗数ｋは１０となる。すると、（例えば）公共工事の増加がも
たらす総雇用は、他の分野への投資の削減がない限り、公共工事自体がもたらす一次雇用の１０倍である。雇用の増加が公共工事のもたらす一次雇用に限られる
ことがあるのは、雇用が増加して実質所得が増えたにもかかわらず、社会がその消費を不変に保ち続ける場合だけである。一方、もし所得の増加のすべてを社会
が消費しようとするなら、安定が取り戻されることはなく、物価は際限なく上昇する。普通の心理状態を仮定するかぎり、雇用が増加して消費が減少するのは同
時に消費性向が変化した場合だけである。例えば、戦時に個人消費を控えるように宣伝が行われた場合がそうである。投資による雇用の増加が、消費財産業の雇
用に対してよい影響を与えないのは、こういう場合だけである。
This only sums up in a formula what should by now be obvious to
the reader on general grounds. An increment of investment in terms of
wage-units cannot occur unless the public are prepared to increase
their savings in terms of wage-units. Ordinarily speaking, the public
will not do this unless their aggregate income in terms of wage-units
is increasing, Thus their effort to consume a part of their increased
incomes will stimulate output until the new level (and distribution) of
incomes provides a margin of saving sufficient to correspond to the
increased investment.
ここでしていることは、今では一般の読者にとって明らかなことをまとめているにすぎない。単位賃金数で測った投資の増加が起きるのは、社会が単位賃金数で
測った貯蓄の増加に積極的な場合だけである。普通に言って、大衆が貯蓄に積極的になるのは、単位賃金数で測った総所得が増加する場合だけである。つまり、
大衆は新たな所得レベルに到達して、投資の増加に対応する貯蓄をするだけの充分な力をもつまで、増えた所得の一部を消費して産出を刺激する努力を続けるの
である。
The multiplier tells us by how much their employment has to be
increased to yield an increase in real income sufficient to induce them
to do the necessary extra saving, and is a function of their
psychological propensities.[3] If saving is the pill and consumption is
the jam, the extra jam has to be proportioned to the size of the
additional pill. Unless the psychological propensities of the public
are different from what we are supposing, we have here established the
law that increased employment for investment must necessarily stimulate
the industries producing for consumption and thus lead to a total
increase of employment which is a multiple of the primary employment
required by the investment itself.
乗数が我々に教えるのは、どれほど雇用が増えたら充分に実質所得が増加して、大衆は必要とされる余分の貯蓄をする気にをなるかということである。つまり、
乗数とは大衆の心理傾向（＝消費性向）の関数なのである[３]。もし貯蓄が丸薬で消費がジャムなら、余分のジャムは追加の丸薬の大きさに比例しなければな
らない。もし社会の心理傾向が我々の想定と異ならないなら、ここで我々は、投資による雇用の増加は消費財産業を刺激して総雇用の増加を導くが、それは投資
が要求した一次雇用のある数倍である、という法則を確立したのである。
It follows from the above that, if the marginal propensity to
consume is not far short of unity, small fluctuations in investment
will lead to wide fluctuations in employment; but, at the same time, a
comparatively small increment of investment will lead to full
employment. If, on the other hand, the marginal propensity to consume
is not much above zero, small fluctuations in investment will lead to
correspondingly small fluctuations in employment; but, at the same
time, it may require a large increment of investment to produce full
employment. In the former case involuntary unemployment would be an
easily remedied malady, though liable to be troublesome if it is
allowed to develop. In the latter case, employment may be less variable
but liable to settle down at a low level and to prove recalcitrant to
any but the most drastic remedies.
これまでのところから次のことがわかる。もし限界消費性向が１よりあまり小さくないなら、投資の僅かな変動は雇用の大きは変動を引き起こす。しかし、それ
と同時に、比較的僅かな投資の増加で完全雇用が達成できる。それに対して、もし限界消費性向がゼロよりあまり大きくないなら、投資の僅かな変動は雇用の比
較的小さな変動を引き起こす。しかし、それと同時に、大きな投資の追加がなければ完全雇用を達成できない。前者の場合、非自発的失業はたやすく癒せる病気
であるが、逆に、一旦非自発的失業の発生をゆるすと重病になりがちである。後者の場合には、雇用は変化しにくいが、低いレベルで安定してしまいがちで、大
胆な治療がなくては中々治らない。
In actual fact the marginal propensity to consume seems to lie
somewhere between these two extremes, though much nearer to unity than
to zero; with the result that we have, in a sense, the worst of both
worlds, fluctuations in employment being considerable and, at the same
time, the increment in investment required to produce full employment
being too great to be easily handled. Unfortunately the fluctuations
have been sufficient to prevent the nature of the malady from being
obvious, whilst its severity is such that it cannot be remedied unless
its nature is understood.
実際には限界消費性向はこの両極端の間のどこかに収まると思われる。ただし、ゼロよりは１の方に近いので、現実は両極端がもつ最悪の部分を併せ持ってい
る。つまり、雇用の変動はかなり大きく、それと同時に、完全雇用をもたらすのに必要な投資の増加はたやすく扱えないほどに大きい。不幸なことに、病気（＝
非自発的失業）はその本質を理解しなければ治療できないほど深刻なのに、雇用の変動が激しくて病気の本質は明らかにできないのだ。
When full employment is reached, any attempt to increase
investment still further will set up a tendency in money-prices to rise
without limit, irrespective of the marginal propensity to consume; i.e.
we shall have reached a state of true inflation.[4] Up to this point,
however, rising prices will be associated with an increasing aggregate
real income.
完全雇用が達成された時には、さらに投資を増やす試みは、限界消費性向の動きとは別に、物価を際限なく上昇させる傾向をもたらすだろう。つまり、その時に
は真性インフレーションの状態に達しているのである[４]。しかしながら、それまでは、物価の上昇は総実質所得の増加を伴うだろう。
III
We have been dealing so far with a net increment of investment. If,
therefore, we wish to apply the above without qualification to the
effect of (eg.) increased public works, we have to assume that there is
no offset through decreased investment in other directions,- and also,
of course, no associated change in the propensity of the community to
consume. Mr. Kahn was mainly concerned in the article referred to above
in considering what offsets we ought to take into account as likely to
be important, and in suggesting quantitative estimates. For in an
actual case there are several factors besides some specific increase of
investment of a given kind which enter into the final result. If, for
example, a Government employs 100,000 additional men on public works,
and if the multiplier (as defined above) is 4, it is not safe to assume
that aggregate employment will increase by 400,000. For the new policy
may have adverse reactions（反作用） on investment in other directions.
第３節
我々はここまで投資の純増加を扱ってきた。したがって、もしこれまでの議論を例えば公共工事の増加の効果に対して無条件に当てはめたいのなら、他の分野へ
の投資の減少による相殺効果がないと仮定しなければならない。さらにまた、それに伴って社会の消費性向に変化がないと仮定しなければならない。カーン氏は
上記の論文のなかで主にどんな相殺効果を考慮することが重要だと思われるかを検討して、量的な評価を示そうとした。というのは、実際のケースでは、投資の
増加以外にも最終的な結果に関わる幾つかの要素があるからである。例えば、もし政府が公共事業で１０万人を追加雇用して、乗数（上で定義した）が４なら、
総雇用は４０万人増えると考えるのは間違いである。というのは、新たな政策は他の分野の投資に逆作用をもたらすかもしれないからである。
It would seem (following Mr. Kahn) that the following are likely
in a modern community to be the factors which it is most important not
to overlook (though the first two will not be fully intelligible until
after Book IV. has been reached):
カーン氏によれば、現代社会においては以下の要素を見落とさないことが非常に大切である。もっとも最初の２つは第４巻に来るまでは充分理解できないかもしれない。
(i) The method of financing the policy and the increased working cash,
required by the increased employment and the associated rise of prices,
may have the effect of increasing the rate of interest and so retarding
investment in other directions, unless the monetary authority takes
steps to the contrary; whilst, at the same time, the increased cost of
capital goods will reduce their marginal efficiency to the private
investor, and this will require an actual fall in the rate of interest
to offset it.
（一）雇用の増加とそれに伴う物価の上昇によって必要となる財政施策の方法と必要資金の追加は、金融当局が対抗策を取らない限り、利子率を上昇させて他の
分野への投資を遅らせる可能性がある。それと同時に、投資財の追加費用は、個人投資家の限界効率を減少させるだろう。それを防止するためには実際に利子率
が下がることが必要となる。
(ii) With the confused psychology which often prevails, the Government
programme may, through its effect on “confidence”（＝確信度）, increase
liquidity-preference or diminish the marginal efficiency of capital,
which, again, may retard other investment unless measures are taken to
offset it.
（ニ）混乱した心理状態が支配的な場合には、政府のプログラムは企業家の「確信度（＝景気見通し）」（＝初出）に対して悪影響を及ぼし、流動性選好（＝初
出、貨幣需要量）を高めてしまうか、あるいは、資本の限界効率を低下させてしまう。防止策を施さないと今度はそれが他の投資を遅らせてしまう。
(iii) In an open system with foreign-trade relations, some part of the
multiplier of the increased investment will accrue to the benefit of
employment in foreign countries, since a proportion of the increased
consumption will diminish our own country's favourable foreign balance;
so that, if we consider only the effect on domestic employment as
distinct from world employment, we must diminish the full figure of the
multiplier. On the other hand our own country may recover a portion of
this leakage through favourable repercussions due to the action of the
multiplier in the foreign country in increasing its economic activity.
（三）海外貿易がある開放経済では、追加投資の乗数の一部は外国の雇用にとって有利に働く。なぜなら、追加消費の一部は自国の貿易収支の黒字を減らすよう
に働くからである。そのため、もし世界の雇用ではなく国内の雇用だけを考えるとしたら、乗数の値を減額しなければならない。その一方で、外国における乗数
の働きがその国の経済活動を活性化することによって、国内での減額分を取り戻す可能性はある。
Furthermore, if we are considering changes of a substantial amount, we
have to allow for a progressive change in the marginal propensity to
consume, as the position of the margin is gradually shifted; and hence
in the multiplier. The marginal propensity to consume is not constant
for all levels of employment, and it is probable that there will be, as
a rule, a tendency for it to diminish as employment increases; when
real income increases, that is to say, the community will wish to
consume a gradually diminishing proportion of it.
さらに、もしかなり大きな量の変化を考えるなら、限界消費性向とそれに伴う乗数が、限界位置の段階的移動に従って、漸進的に変化することを考慮に入れなけ
ればならない。限界消費性向は全ての雇用レベルにおいて一定ではない。概して、おそらくは雇用が増えるにつれて限界消費性向は減少する傾向がある。すなわ
ち、実質所得が増加するときは、社会がその所得を消費する割合は徐々に減少するのである。
There are also other factors, over and above the operation of the
general rule just mentioned, which may operate to modify the marginal
propensity to consume, and hence the multiplier; and these other
factors seem likely, as a rule, to accentuate the tendency of the
general rule rather than to offset it. For, in the first place, the
increase of employment will tend, owing to the effect of
diminishing-returns in the short period, to increase the proportion of
aggregate income which accrues to the entrepreneurs, whose individual
marginal propensity to consume is probably less than the average for
the community as a whole.
限界消費性向と乗数を変えるように働く可能性のある要素は、上記にあげた一般的なルールのほかにも色々ある。それは概して一般的なルールの効果をどちら
かと言えば強めるように働くようである。というのは、第一に、雇用の増加は、短期における収穫逓減効果によって、総所得のうちの企業家に属する割合を増や
す傾向がある。そして、企業家の限界消費性向は社会の平均的な消費性向よりも低いと思われるのである。
In the second place, unemployment is likely to be associated with
negative saving in certain quarters, private or public, because the
unemployed may be living either on the savings of themselves and their
friends or on public relief which is partly financed out of loans; with
the result that re-employment will gradually diminish these particular
acts of negative saving and reduce, therefore, the marginal propensity
to consume more rapidly than would have occurred from an equal increase
in the community's real income accruing in different circumstances.
第二に、失業は一部で公私による負の貯蓄を発生させる。なぜなら、失業した人は自分か友人の貯蓄で生活するか、借入れ金から拠出された公的援助で生活する
からである。再雇用はこのような負の貯蓄を徐々に減らして、限界消費性向を急速に減らして行く。それは違う状況で社会の実質所得が同じだけ増加した場合よ
り急速である。
In any case, the multiplier is likely to be greater for a small
net increment of investment than for a large increment; so that, where
substantial changes are in view, we must be guided by the average value
of the multiplier based on the average marginal propensity to consume
over the range in question.
いずれにせよ、純投資の増加が大きいよりも小さいほうが乗数は大きくなりがちであり、その結果、純投資の大きな変化を考えるときには、必要な範囲内での平均的な限界消費性向に基づく平均的な乗数を基準にすべきである。
Mr. Kahn has examined the probable quantitative result of such factors
as these in certain hypothetical special cases. But, clearly, it is not
possible to carry any generalisation very far. One can only say, for
example, that a typical modern community would probably tend to consume
not much less than 80 per cent. of any increment of real income, if it
were a closed system with the consumption of the unemployed paid for by
transfers from the consumption of other consumers, so that the
multiplier after allowing for offsets would not be much less than 5.
カーン氏は特殊な仮定的ケースでこれらの要因がもたらす結果を大雑把な数量で検討した。しかし、明らかに、一般化をこれ以上進めることは不可能である。例
えば、もしある社会が閉鎖経済で失業者の消費が他の消費者の消費分からの移転によって賄われて、乗数が相殺分を考慮しても５に近い場合には、典型的な現代
社会は、実質所得の増加分の８０％近くを消費に回す傾向があると言えるだけである。
In a country, however, where foreign trade accounts for, say, 20 per
cent. of consumption and where the unemployed receive out of loans or
their equivalent up to, say, 50 per cent. of their normal consumption
when in work, the multiplier may fall as low as 2 or 3 times the
employment provided by a specific new investment. Thus a given
fluctuation of investment will be associated with a much less violent
fluctuation of employment in a country in which foreign trade plays a
large part and unemployment relief is financed on a larger scale out of
borrowing (as was the case, eg., in Great Britain in 1931), than in a
country in which these factors are less important (as in the United
States in 1932).[5]
しかし、外国との貿易が消費の２０％をしめていて、失業者は自分が働いていた時の普段の消費の５０％までを借入れ金等からもらって生活している国では、
乗数は落ちこんで新投資がもたらす雇用を２倍か３倍にしか増やさない可能性がある。つまり、外国との貿易が多くを占めて失業対策が多くの場合借入れ金で賄
われている国（例えば１９３１年の英国）では、こうした要素が有力ではない国（例えば１９３２年の合衆国）よりも、投資の変動が雇用の急激な変動をもたら
すことは遥かに少ない[５]。
It is, however, to the general principle of the multiplier to
which we have to look for an explanation of how fluctuations in the
amount of investment, which are a comparatively small proportion of the
national income, are capable of generating fluctuations in aggregate
employment and income so much greater in amplitude than themselves.
しかしながら、投資量の変動は、それが国民所得の比較的小さい割合でしかなくても、それ自身よりも大きな規模の変動を総雇用と総所得にもたらす可能性があるということの説明は、乗数の一般原理に求めるしかないのである。
IV
The discussion has been carried on, so far, on the basis of a
change in aggregate investment which has been foreseen sufficiently in
advance for the consumption industries to advance pari passu with the
capital-goods industries without more disturbance to the price of
consumption-goods than is consequential,in conditions of decreasing
returns, on an increase in the quantity which is produced.
第４節
これまでの議論は総投資の変化があらかじめ充分予想がつくものとして進めてきた。この予想がつくと、消費財産業は資本財産業と足並みを揃えて進むし、消費財価格の変動も、収穫逓減の条件のもとで生産数が増えるために起きるより大きいことはない。
In general, however, we have to take account of the case where
the initiative comes from an increase in the output of the
capital-goods industries which was not fully foreseen. It is obvious
that an initiative of this description only produces its full effect on
employment over a period of time. I have found, however, in discussion
that this obvious fact often gives rise to some confusion between the
logical theory of the multiplier, which holds good continuously,
without time-lag, at all moments of time, and the consequences of an
expansion in the capital-goods industries which take gradual effect,
subject to time-lag and only after an interval.
しかし、一般的に、資本財産業の産出物が予想外に増加したことから事態が変化するケースも考えておかねばならない。この種の変化が雇用に充分影響を与える
には長い時間がかかるのは明らかである。しかしながら、この明らかな事実のせいで、乗数理論の論理と資本財産業の拡張の結果との間に混乱が起きていること
を、私は議論の間に発見した。乗数理論は継続的にタイムラグなしにいつでも有効なのに、資本財産業の拡張の結果にはタイムラグがあり一定期間の後に徐々に
効果を表すからである。
The relationship between these two things can be cleared up by pointing
out, firstly that an unforeseen, or imperfectly foreseen, expansion in
the capital-goods industries does not have an instantaneous effect of
equal amount on the aggregate of investment but causes a gradual
increase of the latter; and, secondly, that it may cause a temporary
departure of the marginal propensity to consume away from its normal
value, followed, however, by a gradual return to it.
この両者の間の混乱を解決するには次のことを指摘すればよい。それは第一に、予想できないか不完全にしか予想できない資本財産業の拡張は、総投資に対して
同量の効果をすぐに発揮することはなく、後者を徐々に拡大させるということ。第二に、前者が限界消費性向を平常値から乖離させる可能性があり、その後、正
常値に徐々に戻るということである。
Thus an expansion in the capital-goods industries causes a series of
increments in aggregate investment occurring in successive periods over
an interval of time（一定の期間の後に）, and a series of values of the marginal
propensity to consume in these successive periods which differ both
from what the values would have been if the expansion had been foreseen
and from what they will be when the community has settled down to a new
steady level of aggregate investment. But in every interval of time the
theory of the multiplier holds good in the sense that the increment of
aggregate demand is equal to the product（積） of the increment of
aggregate investment and the multiplier as determined by the marginal
propensity to consume.
つまり、資本財産業の拡張は、総投資の一連の増加を一定の期間の後に何期も連続してもたらし、この連続する期間に限界消費性向の一連の値をもたらす。それ
らの値は、資本の拡張が予想されていた場合とも、いずれ社会が落ち着いて新たに安定した総投資レベルになった時とも、異なっている。しかし、総需要の増加
は総投資の増加に乗数（これは消費性向によった決まる）を掛けたものに等しいという意味において、乗数理論は全ての期間において有効である。
The explanation of these two sets of facts can be seen most
clearly by taking the extreme case where the expansion of employment in
the capital-goods industries is so entirely unforeseen that in the
first instance there is no increase whatever in the output of
consumption-goods. In this event the efforts of those newly employed in
the capital-goods industries to consume a proportion of their increased
incomes will raise the prices of consumption-goods until a temporary
equilibrium between demand and supply has been brought about partly by
the high prices causing a postponement of consumption, partly by a
redistribution of income in favour of the saving classes as an effect
of the increased profits resulting from the higher prices, and partly
by the higher prices causing a depletion of stocks（在庫の放出）.
この二つの事実が存在することを最も明確に説明するには、極端なケースを考えれば良い。つまり、資本財産業の雇用の拡張がまったく予想できないもので、最
初のうちは消費財産業の産出には何の増加も見られないというケースである。この場合、資本財産業に新たに雇用された人たちが自分たちの増えた所得の一部を
消費しようとすると、消費財の価格が上昇するだろう。それは、価格の上昇によって、消費が後回しになり、利潤が増えて貯蓄階級のために所得の再分配が行な
れ、在庫が放出されて、需要と供給の一時的な均衡がもたらされるまで続くだろう。
So far as the balance is restored by a postponement of consumption
there is a temporary reduction of the marginal propensity to consume,
i.e. of the multiplier itself, and in so far as there is a depletion of
stocks, aggregate investment increases for the time being by less than
the increment of investment in the capital-goods industries, ― i.e. the
thing to be multiplied does not increase by the full increment of
investment in the capital-goods industries. As time goes on, however,
the consumption-goods industries adjust themselves to the new demand,
so that when the deferred consumption is enjoyed, the marginal
propensity to consume rises temporarily above its normal level, to
compensate for the extent to which it previously fell below it, and
eventually returns to its normal level; whilst the restoration of
stocks to their previous figure causes the increment of aggregate
investment to be temporarily greater than the increment of investment
in the capital-goods industries (the increment of working capital
corresponding to the greater output also having temporarily the same
effect).
需要と供給の均衡が、消費が後回しになることで回復される間は、限界消費性向の一時的な減退が生じるが、それはまさに乗数自体の減退である。また在庫が放
出されて枯渇している場合、総投資の増加は一時的に資本財産業への投資の増加より少ない。つまり、乗数で増える投資は資本財産業の増資を完全には反映しな
いのである。しかし時が経つうちに、消費財産業は新たな需要に適応してきて、後回しにされた消費が実行されると、限界消費性向は一時的に標準レベルを上
回って、以前に標準以下に下落した分を埋め合わせて、そして最後に標準レベルに戻るのである。一方、在庫が以前の数字にまで戻ってくると、総投資の増加は
資本財産業の増資分よりも大きくなってくる（産出量の増加に対応する運転資本の増加も一時的に同じ効果を持つ）。
The fact that an unforeseen change only exercises its full
effect on employment over a period of time is important in certain
contexts;- in particular it plays a part in the analysis of the trade
cycle (on lines such as I followed in my Treatise on Money). But it
does not in any way affect the significance of the theory of the
multiplier as set forth in this chapter; nor render it inapplicable as
an indicator of the total benefit to employment to be expected from an
expansion in the capital-goods industries. Moreover, except in
conditions where the consumption industries are already working almost
at capacity so that an expansion of output requires an expansion of
plant and not merely the more intensive employment of the existing
plant, there is no reason to suppose that more than a brief interval of
time need elapse before employment in the consumption industries is
advancing pars passu with employment in the capital-goods industries
with the multiplier operating near its normal figure.
予期せぬ変化がその効果を完全に発揮するのはある期間の後であるという事実は、ある文脈で重要である。特にこの事実は景気循環を分析する際にある役割を果
たす（例えば私が『貨幣論』でたどった文脈）。しかし、この事実から、この章で提示された乗数理論の意味が変わることはないし、投資財産業の拡大から期待
できる雇用への全体的利益の指標として、乗数理論が使えないということにもならない。さらに、消費財産業が既にほぼフル操業状態で産出量の拡大には単に既
存のプラントの活用度を上げるだけではなくプラント自体の拡大が必要となっている場合以外には、乗数が正常値の近くにある場合には、消費財産業の雇用が資
本財産業の雇用と同時に発展するには長い時間の経過が必要であるとと考える理由はないのである。
V
We have seen above that the greater the marginal propensity to
consume, the greater the multiplier, and hence the greater the
disturbance to employment corresponding to a given change in
investment. This might seem to lead to the paradoxical conclusion that
a poor community in which saving is a very small proportion of income
will be more subject to violent fluctuations than a wealthy community
where saving is a larger proportion of income and the multiplier
consequently smaller.
第５節
限界消費性向が大きくなると乗数も大きくなり、投資の変化に対応する雇用の変動も大きくなるということを我々は上記で見た。ここから我々は、貯蓄が所得の
非常に小さい部分を占めるような貧しい社会では、貯蓄が所得の大きな割合を占める（従って乗数も比較的小さい）豊かな社会よりは、激しい変動が起きやすい
という逆説的な結論に至るかのように見える。
This conclusion, however, would overlook the distinction between
the effects of the marginal propensity to consume and those of the
average propensity to consume. For whilst a high marginal propensity to
consume involves a larger proportionate effect from given percentage
change in investment, the absolute effect will, nevertheless, be small
if the average propensity to consume is also high. This may be
illustrated as follows by a numerical example.
しかしこの結論は、限界消費性向と平均消費性向のもつ効果の違いを見逃した結果である。というのは、限界消費性向が高いと投資の割合の変化から相対的に大
きな効果が得られるが、もし同時に平均消費性向も高いと絶対的な効果は小さくなる。これは数字を伴う次の実例によって説明できる。
Let us suppose that a community's propensity to consume is such
that, so long as its real income does not exceed the output from
employing 5,000,000 men on its existing capital equipment, it consumes
the whole of its income; that of the output of the next 100,000
additional men employed it consumes 99 per cent., of the next 100,000
after that 98 per cent., of the third 100,000 97 per cent. and so on;
and that 10,000,000 men employed represents full employment. It follows
from this that, when 5,000,000 + n x 100,000 men are employed, the
multiplier at the margin is 100/n, and n(n + 1)/2.(50 + n) per cent. of
the national income is invested.
社会の消費性向は次のようであるとする。まず、現存投資設備のもとで社会の実質所得が５００万人の雇用から生まれる産出量を超えない間は、社会はその所得
の全てを消費する。そして、追加の１０万人の雇用から生まれる産出量の９９％を社会は消費し、次の１０万人の追加から生まれる産出量の９８％を社会は消費
し、三番目の１０万人の産出量の９７％等々となる。さらに、１千万人の雇用が完全雇用であるとすると、５００万人＋ｎ×１０万人が雇用された時（＝
（１００ーｎ）％を消費する）、限界値の乗数は１００／ｎであり、（＝投資量はΣ１０ｎ／１００＝ｎ（ｎ＋１）／２０）国民所得のｎ（ｎ＋１）／２（５０
＋ｎ）パーセントが投資されていることになる。
Thus when 5,200,000 men are employed the multiplier is very
large, namely 50, but investment is only a trifling proportion of
current income, namely, 0.06 per cent.; with the result that if
investment falls off by a large proportion, say about two-thirds,
employment will only decline to 5,100,000, i.e. by about 2 per cent. On
the other hand, when 9,000,000 men are employed, the marginal
multiplier is comparatively small, namely 2.5, but investment is now a
substantial proportion of current income, namely, 9 per cent.; with the
result that if investment falls by two-thirds, employment will decline
to 7,300,000, namely, by 19 per cent. In the limit where investment
falls off to zero, employment will decline by about 4 per cent. in the
former case, whereas in the latter case it will decline by 44 per
cent.[6]
つまり、５２０万人が雇用されているとき乗数は５０と非常に大きいが、所得にしめる投資の割合はわずか０．０６％にすぎないから、投資が例えば３分の２と
いう大きな割合だけ減額しても、雇用は２％減って５１０万人になるだけである。それに対して、９００万人が雇用されているときには、限界乗数は比較的小さ
くて２．５となるが、投資は現行所得の９％とかなりの部分を占めているので、投資が３分の２だけ減ると、雇用は１９％減って７３０万人になる。投資がゼロ
にまで落ちる極端な場合では、前者は雇用が４％だけ下落するだけだが、後者は４４％下落する[６]。
In the above example, the poorer of the two communities under
comparison is poorer by reason of under-employment. But the same
reasoning applies by easy adaptation if the poverty is due to inferior
skill, technique or equipment. Thus whilst the multiplier is larger in
a poor community, the effect on employment of fluctuations in
investment will be much greater in a wealthy community, assuming that
in the latter current investment represents a much larger proportion of
current output.[7]
上記の例では、比較対象となる二つの社会のうちで貧しい方は雇用不足のために貧しいのであるが、貧しさが技術不足や設備不足のためであっても、簡単な修正
を加えれば同じ理屈が当てはまる。つまり、貧しい社会では乗数は大きいが、豊かな社会においては現行の投資が現行産出量の大きな部分を占める場合には、投
資の変動が雇用に与える影響は豊かな社会の方が大きいのである[７]。
It is also obvious from the above that the employment of a given
number of men on public works will (on the assumptions made) have a
much larger effect on aggregate employment at a time when there is
severe unemployment, than it will have later on when full employment is
approached. In the above example, if, at a time when employment has
fallen to 5,200,000, an additional 100,000 men are employed on public
works, total employment will rise to 6,400,000. But if employment is
already 9,000,000 when the additional 100,000 men are taken on for
public works, total employment will only rise to 9,200,000. Thus public
works even of doubtful utility may pay for themselves over and over
again at a time of severe unemployment, if only from the diminished
cost of relief expenditure, provided that we can assume that a smaller
proportion of income is saved when unemployment is greater; but they
may become a more doubtful proposition as a state of full employment is
approached. Furthermore, if our assumption is correct that the marginal
propensity to consume falls off steadily as we approach full
employment, it follows that it will become more and more troublesome to
secure a further given increase of employment by further increasing
investment.
以上から、公共事業の一定数の雇用は（上記の想定のもとで）深刻な失業の時の方が完全雇用が達成されそうな時よりも総雇用数に大きな影響を与えるのは明白
である。上記の例では、雇用が５２０万人まで落ち込んでいる時に、公共事業に追加の１０万人の雇用があった場合には、総雇用数は６４０万人に跳ね上がる。
しかし、もし雇用がすでに９００万人になっているなら公共事業による追加の１０万人の雇用があっても、総雇用数は９２０万人に増えるだけである。つまり、
深刻な失業の時には所得から貯蓄される割合が減少すると仮定する場合には、深刻な失業の時には効果の疑わしい公共事業でも、失業手当の費用が減るという意
味だけからも、何度やっても効果がある。しかし、完全雇用が近づいている段階では、公共投資の効果はどんどん疑わしくなってくる。さらに、完全雇用に近づ
くにつれて限界消費性向が徐々に低下するという我々の想定が正しければ、さらに投資を増やして一定の雇用数を増やすことはますます困難になってくる。
It should not be difficult to compile a chart of the marginal
propensity to consume at each stage of a trade cycle from the
statistics (if they were available) of aggregate income and aggregate
investment at successive dates. At present, however, our statistics are
not accurate enough (or compiled sufficiently with this specific object
in view) to allow us to infer more than highly approximate estimates.
The best for the purpose, of which 1 am aware, are Mr. Kuznets' figures
for the United States (already referred to in Chapter 8 above), though
they are, nevertheless, very precarious. Taken in conjunction with
estimates of national income these suggest, for what they are worth,
both a lower figure and a more stable figure for the investment
multiplier than I should have expected. If single years are taken in
isolation, the results look rather wild. But if they are grouped in
pairs, the multiplier seems to have been less than 3 and probably
fairly stable in the neighbourhood of 2.5.
総所得と総投資の連続した日々の統計（もしあればだが）から、景気循環の各ステージにおける限界消費性向のグラフを作ることは難しいことではないはずだ。
しかしながら、現状では、我々の統計は不正確で（あるいは特殊な目的のためだけに作られたものなので）極めて蓋然的な見積りしか推定することが出来ない。
この目的のために私が知っている最善のものは、合衆国についてのクズネッツ氏の数字（すでに第８章で見た）である。ただし、その数字は不確かなものであ
る。国民所得の概算と並べてみると、その数字は現状では投資乗数にとっては私が期待する以上に低く安定した数字に見える。個別の年度を別に取り出したら、
結果はかなり不規則に見えるが、二つずつ並べてみると、乗数は３よりも小さく２．５の近辺でかなり安定しているように見えるのである。
This suggests a marginal propensity to consume not exceeding 60 to 70
per cent. ― a figure quite plausible for the boom, but surprisingly,
and, in my judgment, improbably low for the slump. It is possible,
however, that the extreme financial conservatism of corporate finance
in the United States, even during the slump, may account for it. In
other words, if, when investment is falling heavily through a failure
to undertake repairs and replacements, financial provision is made,
nevertheless, in respect of such wastage, the effect is to prevent the
rise in the marginal propensity to consume which would have occurred
otherwise. I suspect that this factor may have played a significant
part in aggravating the degree of the recent slump in the United
States. On the other hand, it is possible that the statistics somewhat
overstate the decline in investment, which is alleged to have fallen
off by more than 75 percent. in 1932 compared with 1929, whilst net
“capital formation” declined by more than 95 per cent.; ― a moderate
change in these estimates being capable of making a substantial
difference to the multiplier.
この事実は限界消費性向が６０％から７０％を超えないということを示唆している。つまり、好景気の時には極めてありそうな数字なのだ。しかし不況の時には
驚くべきほどに、そして私の判断では、あり得ないほどに低い数字である。しかしながら、合衆国においては企業会計は財政面で極端な保守主義であることが、
その説明になるかもしれない。言い換えれば、もし修理や取替えが進まずに投資がひどく落ち込んでいる時に、それにも関わらず、その消耗に対する準備金が設
定される場合には、それがなければ上昇していたはずの限界消費性向を抑えることになってしまう。この要因は合衆国の最近の不況を悪化させるのに大きな役割
を果たしていると私は思っている。その一方で、統計は投資の下落をいくらか強調しすぎている可能性がある。１９２９年に比べて１９３２年には投資が７５％
も落ち込み、純資本形成は９５％も落ち込んだとされているからである。これらの概算値はわずかに違うだけでも乗数に対して大きな変化をもたらす可能性があ
る。
VI
When involuntary unemployment exists, the marginal disutility of
labour is necessarily less than the utility of the marginal product.
Indeed it may be much less. For a man who has been long unemployed some
measure of labour, instead of involving disutility, may have a positive
utility. If this is accepted, the above reasoning shows how “wasteful”
loan expenditure[8] may nevertheless enrich the community on balance.
Pyramid-building, earthquakes, even wars may serve to increase wealth,
if the education of our statesmen on the principles of the classical
economics stands in the way of anything better.
第６節
非自発的失業が存在するときは、労働力の限界不効用は必然的に限界生産物の効用を下回っている（＝第３章２節、実質賃金の高止まり）。実際には、かなり下
回っている可能性がある。それどころか、失業が長い人にとっては、ある程度の労働は不効用（＝苦痛）ではなくて、プラスの効用をもつ可能性がある。もしそ
うなら、上記の理屈でいけば「不経済」な公債支出[８]でも、結果としては社会を富ませる可能性があるということになる。我々の政治家たちが古典経済学の
原理の教育を受けたせいでもっとましな手段をとれないのなら、ピラミッド建設や地震や戦争でさえも富を増やすのに役立つ可能性があるのである。
It is curious how common sense, wriggling for an escape from
absurd conclusions, has been apt to reach a preference for wholly
“wasteful” forms of loan expenditure rather than for partly wasteful
forms, which, because they are not wholly wasteful, tend to be judged
on strict “business” principles. For example, unemployment relief
financed by loans is more readily accepted than the financing of
improvements at a charge below the current rate of interest; whilst the
form of digging holes in the ground known as gold-mining, which not
only adds nothing whatever to the real wealth of the world but involves
the disutility of labour, is the most acceptable of all solutions.
部分的に「不経済」な公債支出の方が完全に「不経済」ではないために厳密な「経営」原理に則っていると見られるにも関わらず、我々は常識にしたがって不合
理な結論を免れようとしながら、部分的に「不経済」な公債支出よりも完全に「不経済」な公債支出を選ぶ傾向があるのは奇妙なことである。例えば、公債から
拠出した失業手当の方が、雇用改善の低利融資よりも容易に受け入れられている。いやそれどころか、金採掘として知られる穴掘りは、世界の実際の富を一切増
やさないだけでなく労働の不効用を伴うにも関わらず、あらゆる解決策の中でもっとも好まれているのだ。
If the Treasury were to fill old bottles with banknotes, bury
them at suitable depths in disused coalmines<,>which are then
filled up to the surface with town rubbish, and leave it to private
enterprise on well-tried principles of laissez-faire to dig the notes
up again (the right to do so being obtained, of course, by tendering
for leases of the note-bearing territory), there need be no more
unemployment and, with the help of the repercussions, the real income
of the community, and its capital wealth also, would probably become a
good deal greater than it actually is. It would, indeed, be more
sensible to build houses and the like; but if there are political and
practical difficulties in the way of this, the above would be better
than nothing.
もし大蔵省が古い壺に紙幣を詰めて、廃坑になった炭鉱に適度な深さに埋めて、その上に町のゴミを満たして、その後で、多くの試練に耐えてきた自由放任主義
に基づいて、民間企業にその紙幣を掘り出させたなら（採掘権はもちろん紙幣を生む土地の賃貸権の入札によって入手できる）もはや失業は存在する必要がなく
なる。また、その影響を受けて、社会の実質所得と資本資産もおそらく現実にあるよりもはるかに大きくなるだろう。もちろん、これより家を建てるなどのやり
方のほうが実際的であろう。しかし、政治的にも実際的にもこういう手段がとれないような困難な事情があるなら、何もしないよりは上記のことをする方がまし
だろう。
The analogy between this expedient and the goldmines of the real
world is complete. At periods when gold is available at suitable depths
experience shows that the real wealth of the world increases rapidly;
and when but little of it is so available, our wealth suffers
stagnation or decline. Thus gold-mines are of the greatest value and
importance to civilisation. Just as wars have been the only form of
large-scale loan expenditure which statesmen have thought justifiable,
so gold-mining is the only pretext for digging holes in the ground
which has recommended itself to bankers as sound finance; and each of
these activities has played its part in progress―failing something
better. To mention a detail, the tendency in slumps for the price of
gold to rise in terms of labour and materials aids eventual recovery,
because it increases the depth at which gold-digging pays and lowers
the minimum grade of ore（＝鉱石） which is payable.
この方法と現実世界の金鉱は非常によく似ている。経験の教えるところでは、金が適当な深さで採掘できる間は世界の実際の富は急速に増加して（＝理論の上記
と経験は逆）、金がなかなか採れなくなると世界の富は停滞か下り坂に入るのだ。つまり、金鉱は文明にとって最大の価値と重要性があるのだ。戦争が政治家た
ちによって正当化されてきた唯一の大規模な公債支出であるのと同じく、金の採掘は銀行家たちに健全な融資策として歓迎されてきた唯一の穴掘りなのである。
それよりましな方法がない状況では、これらはどちらも人類の進歩に貢献してきたのである。もっと詳しく言うなら、不況のときに労働と原材料で測った金の価
格の上昇傾向が景気の回復を最終的に助けるのである。なぜなら、金の価格の上昇は、儲かる金採掘の深度と儲かる原材料の最低グレードを引き下げるからであ
る。
In addition to the probable effect of increased supplies of gold
on the rate of interest, gold-mining is for two reasons a highly
practical form of investment, if we are precluded from increasing
employment by means which at the same time increase our stock of useful
wealth. In the first place, owing to the gambling attractions which it
offers it is carried on without too close a regard to the ruling rate
of interest. In the second place the result, namely, the increased
stock of gold, does not, as in other cases, have the effect of
diminishing its marginal utility. Since the value of a house depends on
its utility, every house which is built serves to diminish the
prospective rents obtainable from further house-building and therefore
lessens the attraction of further similar investment unless the rate of
interest is falling part passu. But the fruits of gold-mining do not
suffer from this disadvantage, and a check can only come through a rise
of the wage-unit in terms of gold, which is not likely to occur unless
and until employment is substantially better. Moreover, there is no
subsequent reverse effect on account of provision for user and
supplementary costs, as in the case of less durable forms of wealth.
金採掘は金の供給を増やして利子率に影響を与えるだけでなく、もし我々が効用ある富のストックを増加させると同時に雇用を増やす手段が見つからない場合に
は、次の二つの理由で極めて実際的な投資形態である。その第一の理由は、金採掘はそれが提供するギャンブル的な魅力によって、支配的な利子率をあまり気に
することなく実行できることであり、その第二の理由は、金採掘ではその結果金のストックが増えても他の場合と違って限界効用が減少しないことである。家の
価値はその効用に依存しているから、新たに家が建てられるごとに家を建てることから得られる将来の家賃は下がっていくので、利子率が同時に低下しない限
り、同じ投資を繰り返す魅力は減少する。ところが、金採掘から得られる金の蓄えにはこのような不都合はない。利益を妨げる要素があるとすれば、それは金で
測った単位賃金の上昇だけであるが、そんなことは雇用がかなり改善されない限り起こりそうもない。さらに、耐久性の低い資産の場合と違って、利用費用や補
足費用のための蓄えによって不利な作用が起きることもない。
Ancient Egypt was doubly fortunate, and doubtless owed to this its
fabled wealth, in that it possessed two activities, namely,
pyramid-building as well as the search for the precious metals, the
fruits of which, since they could not serve the needs of man by being
consumed, did not stale with abundance. The Middle Ages built
cathedrals and sang dirges. Two pyramids, two masses for the dead, are
twice as good as one; but not so two railways from London to York. Thus
we are so sensible, have schooled ourselves to so close a semblance of
prudent financiers, taking careful thought before we add to the
“financial” burdens of posterity by building them houses to live in,
that we have no such easy escape from the sufferings of unemployment.
We have to accept them as an inevitable result of applying to the
conduct of the State the maxims which are best calculated to “enrich”
an individual by enabling him to pile up claims to enjoyment which he
does not intend to exercise at any definite time.
古代エジプトはピラミッド建設と金鉱探索という二つの事業をもっていたために、二重の意味で幸福だったし、疑いもなくエジプトの伝説的な富はこの二つの事
業のおかげだった。これらの事業から得られたものは、消費されて人々の必要を満たすものではなかったので、いくら増えても陳腐化することがなかったからで
ある。中世では大聖堂が建てられて大々的に葬儀が営まれた。二つのピラミッドと二つのミサは一つピラミッドと一つのミサと比べて二倍の価値がある。しか
し、ロンドンからヨークに至る二本の線路は一つの線路の二倍の価値はない。つまり、現代の我々はあまりに分別があり、経済的な資本家そっくりに振る舞うこ
とを身に着けているので、孫が住む家を建てることによって孫の経済的な負担を増やす前に、慎重な考慮を巡らせる。そのおかげで我々は失業という苦難からの
解決策をたやすく手に入れることが出来ないのである。我々は個人が「金持ちになる」ために周到に計算された行動指針を国家の行動に適応したために、その避
けがたい結果として失業という苦難を受け入れねばならないのである。その行動指針とは、自分がいつまでも実際に行使する気のない享楽の請求権（＝流動性）
を際限もなく積み上げることである。
Author's Footnotes
[1]. More precisely, if ee and e'e are the elasticities of employment
in industry as a whole and in the investment industries respectively;
and if N and N2 are the numbers of men employed in industry as a whole
and in the investment industries, we have
ΔYw = Yw/(ee.N) .ΔN and ΔIw = Iw/(e'e.N2).ΔN2, so that
ΔN = (ee/e'e).(Iw/N2).(N/Yw).k.ΔN2, i.e., k' = (Iw/e'eN2).(eeN/Yw).k.
If however, there is no reason to expect any material relevant
difference in the shapes of the aggregate supply functions for industry
as a whole and for the investment industries respectively, so that
Iw/(ee'.N2) = Yw/(ee.N), then it follows that ΔYw/ΔN = ΔIw/ΔN2 and,
therefore, that k = k'.
著者注
[１] より正確に言うと、ｅｅとｅ'ｅを産業全体の雇用の弾力性（＝２０章に定義がある、賃金にたいする雇用の弾力性）、投資産業の雇用の弾力性とし、もしＮとＮ２が産業全体の雇用者数、投資産業の雇用者数とすると、
ΔＹｗ = （Ｙｗ／ｅｅ）×（ΔＮ／Ｎ）（←ｅｅ＝ΔＮ／Ｎ×Ｙｗ／ΔＹｗ）、
および
ΔＩｗ = （Ｉｗ／ｅ'ｅ）×（ΔＮ２／Ｎ２）（←ｅ'ｅ＝ΔＮ２／Ｎ２×Ｉｗ／ΔＩｗ）、
したがって
ΔＮ = (ｅｅ／ｅ'ｅ)×(Ｉｗ／Ｎ２)×(Ｎ／Ｙｗ)×ｋ×ΔＮ２（←ｋ＝ΔＹｗ／ΔＩｗ＝（Ｙｗ／ｅｅ）×（ΔＮ／Ｎ）×（ｅ'ｅ／Ｉｗ）×（Ｎ２／ΔＮ２））、
つまり
ｋ' = (Ｉｗ／（ｅ'ｅ×Ｎ２）).(ｅｅ×Ｎ／Ｙｗ)×ｋ（←ｋ'＝ΔＮ／ΔＮ２、ｋ' = (ｅｅ／ｅ'ｅ)×(Ｉｗ／Ｎ２)×(Ｎ／Ｙｗ)×ｋ）、
しかし、もし産業全体の総供給関数の形と投資産業の総供給関数の形に大きな違いを予想する理由がなく、
Ｉｗ／(ｅｅ'×Ｎ２) = Ｙｗ／(ｅｅ×Ｎ)なら、ΔＹｗ／ΔＮ = ΔＩｗ／ΔＮ２ なので ｋ = ｋとなる。'
[2]. Our quantities are measured throughout in terms of wage-units.
[２] 我々の量は単位賃金数で測ったものである。
[3]. Though in the more generalised case it is also a function of the
physical conditions of production in the investment and consumption
industries respectively.
[３] ただし、もっと一般的な場合には、乗数とは、投資産業と消費産業のそれぞれの生産の物理的条件の関数である。
[4]. Cf. Chapter 21, p. 303, below.
[４] ２１章３０３頁参照
[5]. Cf., however, below, p. 128, for an American estimate.
[５] アメリカの数字については１２８頁参照。
[6]. Quantity of investment is measured, above, by the number of men
employed in producing it. Thus if there are diminishing returns per
unit of employment as employment increases, what is double the quantity
of investment on the above scale will be less than double on a physical
(if such a scale is available).
[６] 投資量はそれを生産するために雇用される人数で測られる。つまり、もし雇用が増えて雇用１単位あたりの収穫が低減するなら、雇用の尺度で測った投資の二倍は物理的尺度（そのような尺度があればだが）で測った投資の二倍より少ない
[7]. More generally, the ratio of the proportional change in total demand to the proportional change in investment
= (ΔY/Y)/(ΔI/I) = (ΔY/Y).{(Y - C)/(ΔY - ΔC)} = (1 - C/Y)/(1 - dC/dY)
As wealth increases dC/dY diminishes, but C/Y also diminishes. Thus the
fraction increases or diminishes according as consumption increases or
diminishes in a smaller or greater proportion than income.
[７] もっと一般的に言えば、総需要の変化率と投資の変化率の比率は
= (ΔＹ／Ｙ)／(ΔＩ／Ｉ) = (ΔＹ／Ｙ)×{(Ｙ - Ｃ)／(ΔＹ - ΔＣ)} = (1 - Ｃ／Ｙ)／(1 - ｄＣ／ｄＹ)
（←Ｉ＝ＹーＣ））
富が増すに連れてｄＣ／ｄＹは減る。しかしＣ／Ｙも減る。つまりこの分数の値は消費が所得より大きい割合で増えたら増えるし、小さい割合で増えたら減る。また消費が所得より大きい割合で減ったら減るし、小さい割合で減ったら増える。
[8]. It is often convenient to use the term “loan expenditure“ to include both public investment financed by borrowing from individuals and also any other current public expenditure which is so financed.
Strictly speaking, the latter should be reckoned as negative saving, but official action of this kind is not influenced by the same sort of psychological motives as those which govern private saving. Thus “loan
expenditure” is a convenient expression for the net borrowings of public authorities on all accounts, whether on capital account or to meet a budgetary deficit. The one form of loan expenditure operates by
increasing investment and the other by increasing the propensity to consume.
[８]
個人からの借入れで賄われた公共投資と当期の公共支出のことを「公債支出」という言葉で呼ぶのがしばしば便利である。厳密に言えば、後者はマイナス貯蓄と
考えるべきであるが、この種の公的活動は個人の貯蓄を左右する心理的動機には影響されない。したがって、「公債支出」という言葉は資本勘定、赤字予算など公共団体のあらゆる純借入れを表すのに好都合な表現なのである。公債支出でも前者のタイプは投資を増やすし、後者のタイプは消費性向を増やすのであ
る。
Book IV The Inducement to Invest
第４巻 投資誘引
Chapter 11. The Marginal Efficiency of Capital
第１１章 資本の限界効率
I
WHEN a man buys an investment or capital-asset, he purchases the
right to the series of prospective returns, which he expects to obtain
from selling its output, after deducting the running expenses of
obtaining that output, during the life of the asset. This series of
annuities（年金） Q1, Q2, ... Qn it is convenient to call the prospective
yield of the investment.
第１節
人が投資物件や資本資産を購入するとき、彼はその資産が廃棄されるまでに生み出す産出物を売って得られる一連の予想収益（産出物を得るための費用は差し引
く）の権利を買うのである。この一連の毎年の利益（＝年金）Ｑ１, Ｑ２, ... Ｑｎを「投資の予想収益」と呼ぶのが便利である。
Over against the prospective yield of the investment we have the supply
price of the capital-asset, meaning by this, not the market-price at
which an asset of the type in question can actually be purchased in the
market, but the price which would just induce a manufacturer newly to
produce an additional unit of such assets, i.e. what is sometimes
called its replacement cost.
この投資の予想収益の計算式の反対側に来るのが資本資産の「供給価格」である。供給価格とはそのタイプの資産が市場で実際に購入できる市場価格（＝需要価
格）ではなく、業者が同じ機械を新たにもう一単位作る気になるような価格で、時には「再投資費用（＝更新費用、更新原価）」と呼ばれるものである。
The relation between the prospective yield of a capital-asset and its
supply price or replacement cost, i.e. the relation between the
prospective yield of one more unit of that type of capital and the cost
of producing that unit, furnishes us with the marginal efficiency of
capital of that type.
ある資本資産の予想収益とその供給価格（あるいは再投資費用）の関係は、すなわち、そのタイプの追加資本一単位の予想収益とその追加資本一単位を作る価格との関係であり、それをそのタイプの「資本の限界効率」という。
More precisely, I define the marginal efficiency of capital as being
equal to that rate of discount which would make the present value of
the series of annuities given by the returns expected from the
capital-asset during its life just equal to its supply price. This
gives us the marginal efficiencies of particular types of
capital-assets. The greatest of these marginal efficiencies can then be
regarded as the marginal efficiency of capital in general.
もっと正確に言うなら、資本の限界効率とは、その資本資産が廃棄されるまでの予想収益からなる毎年の利益の合計の現在価値とその資本の供給価格とを等しく
するような比率のことである。これが個々のタイプの資産の限界効率である。これらの限界効率うちの最大のものを資本全体の限界効率と見ることが出来る。
The reader should note that the marginal efficiency of capital is here
defined in terms of the expectation of yield and of the current supply
price of the capital-asset. It depends on the rate of return expected
to be obtainable on money if it were invested in a newly produced
asset; not on the historical result of what an investment has yielded
on its original cost if we look back on its record after its life is
over.
読者は、ここで資本の限界効率が資本資産（＝機械）の予想収益とその現在の供給価格によって定義されていることに留意して欲しい。もしその投資が新品の資
産に対して行われたのなら、資本の限界効率とは予想収益に依存するものであり、その機械が廃棄された後で振り返ってみて実際に生み出された収益の結果とは
関係ない。
If there is an increased investment in any given type of capital
during any period of time, the marginal efficiency of that type of
capital will diminish as the investment in it is increased, partly
because the prospective yield will fall as the supply of that type of
capital is increased, and partly because, as a rule, pressure on the
facilities for producing that type of capital will cause its supply
price to increase;
ある期間内にあるタイプの資本（＝機械）の投資が増えた場合には、その投資が増えた分だけそのタイプの資本の限界効率は減少するが、それは、そのタイプの
資本の供給が増えるに従って予想収益が減るからであり、またそのタイプの資本（＝機械）を作る工場が忙しくなるとその資本（＝機械）の供給価格が上がるか
らである。
the second of these factors being usually the more important in
producing equilibrium in the short run, but the longer the period in
view the more does the first factor take its place. Thus for each type
of capital we can build up a schedule, showing by how much investment
in it will have to increase within the period, in order that its
marginal efficiency should fall to any given figure. We can then
aggregate these schedules for all the different types of capital, so as
to provide a schedule relating the rate（仏訳では量、古い英語でも量） of aggregate
investment to the corresponding marginal efficiency of capital in
general which that rate of investment will establish. We shall call
this the investment demand-schedule; or, alternatively, the schedule of
the marginal efficiency of capital.
この内では二つ目の要素の方が均衡状態をもたらすために短期では重要な役割をもっているが、長期では一つ目の要素の方が重要な役割を果たす。そこで資本の
タイプごとに、ある数字まで資本の限界効率が下がるにはその資本への投資がどれだけ増える必要があるかを示す一覧表（＝グラフ）を作る事が出来る。そして
その様々なタイプの全ての資本についての投資と限界効率の一覧表を集計して、総投資量とその投資量よって決まる資本全体の限界効率を結びつける一覧表を作
ることが出来る。これを我々は投資需要表、あるいは、資本の限界効率表と呼ぶことができる。
Now it is obvious that the actual rate（額、量） of current
investment will be pushed to the point where there is no longer any
class of capital-asset of which the marginal efficiency exceeds the
current rate of interest. In other words, the rate of investment will
be pushed to the point on the investment demand-schedule where the
marginal efficiency of capital in general is equal to the market rate
of interest.[1]
すると、現行利子率を超えるような限界効率（＝予想収益率）をもつような資本がもう存在しないところまで、投資量が押し上げられるのは明らかである。言い
換えれば、投資量は投資需要表の上の資本の限界効率が市場利子率に一致するところまで押し上げられるのである（＝内部収益率法）。[１]
The same thing can also be expressed as follows. If Qr is the
prospective yield from an asset at time r, and dr is the present value
of ￡1 deferred（据え置いた） r years at the current rate of interest, ΣQrdr,
is the demand price of the investment; and investment will be carried
to the point where ΣQrdr becomes equal to the supply price of the
investment as defined above. If, on the other hand, ΣQrdr, falls short
of the supply price, there will be no current investment in the asset
in question.
同じ事は次のようにも言える（＝割引現在価格法）。Ｑｒをある資本資産のｒ年目の予想収益とし、ｄｒを現行利子率でのｒ年目の１ポンドの現在価値とする
と、ΣＱｒ×ｄｒがその投資資産の需要価格（＝資本の需要価格）となる（＝ｄｒは１／（１＋利子率）、１／（１＋利子率）の２乗、・・・ｒ乗）。そして、
ΣＱｒ×ｄｒが上で言った投資の供給価格（＝資本の供給価格）に等しくなる点まで投資（＝資本の追加）は行われる。逆に、ΣＱｒ×ｄｒが供給価格を下回る
とき、もう新たな投資は行われない。
It follows that the inducement to invest depends partly on the
investment demand-schedule and partly on the rate of interest. Only at
the conclusion of Book IV. will it be possible to take a comprehensive
view of the factors determining the rate of investment in their actual
complexity. I would, however, ask the reader to note at once that
neither the knowledge of an asset's prospective yield nor the knowledge
of the marginal efficiency of the asset enables us to deduce either the
rate of interest or the present value of the asset. We must ascertain
the rate of interest from some other source, and only then can we value
the asset by “capitalising”（英語はcapitalizing） its prospective yield.
以上から、投資誘引は投資需要表にも依存するし利子率にも依存することになる。しかし、投資量を決める要素の複雑な全体像を知るためには、第４巻の最後ま
で来ないと分からないだろう。ここで注意を喚起したいのは、ある資産の予想収益がわかっても資本の限界効率が分かっても、そこから利子率は分からないし資
産の現在価値も分からないということである。利子率は他のことから知るしかないのである。そして利子率が分かって初めて資産の予想収益を「資本に組み入れ
る」ことで、資産の価値を知ることが出来るのだ。
II
How is the above definition of the marginal efficiency of
capital related to common usage? The Marginal Productivity or Yield or
Efficiency or Utility of Capital are familiar terms which we have all
frequently used. But it is not easy by searching the literature of
economics to find a clear statement of what economists have usually
intended by these terms.
第２節 一般的な用語と上記の考え方とのつながり
上記の資本の限界効率の定義は一般的な用語とどうつながっているだろうか。「資本の限界生産力、限界収益、限界効率、限界効用」は馴染みの用語で誰もがよ
く使ってきた。しかし、これらの用語を経済学者たちがどういう意味で使ってきたかを、彼らの書いたものから見つけることは容易なことではない。
There are at least three ambiguities to clear up. There is, to begin
with, the ambiguity whether we are concerned with the increment of
physical product per unit of time due to the employment of one more
physical unit of capital, or with the increment of value due to the
employment of one more value unit of capital. The former involves
difficulties as to the definition of the physical unit of capital,
which I believe to be both insoluble and unnecessary. It is, of course,
possible to say that ten labourers will raise more wheat from a given
area when they are in a position to make use of certain additional
machines; but I know no means of reducing this to an intelligible
arithmetical ratio which does not bring in values. Nevertheless many
discussions of this subject seem to be mainly concerned with the
physical productivity of capital in some sense, though（そして） the writers
fail to make themselves clear.
明らかでない点が少なくとも三つある。それらを解決していこう。まず第一に、我々が扱っているのは、資本の物理的な一単位を追加して使用することに起因す
る単位時間あたりの物理的な産出物の追加なのか、資本の価値一単位を追加して使用することに起因する価値の追加なのかが明確ではない。前者は資本の物理的
な単位の定義が困難であり、またこの困難の解決は不可能でありまた解決は不要であると私は信じている。もちろん、設備の追加的使用によって１０人の労働者
が一定の区域から収穫する小麦の量が増えると言うことは出来る。しかし、このことを計算可能な比率に還元するには、価値を持ち込むしかないのである。それ
にも関わらず、このテーマについての多くの議論は主に資本の物理的な生産力に関するものであるようである。そして、それらは理解可能なものになっていない
のである。
Secondly, there is the question whether the marginal efficiency of
capital is some absolute quantity or a ratio. The contexts in which it
is used and the practice of treating it as being of the same dimension
as the rate of interest seem to require that it should be a ratio. Yet
it is not usually made clear what the two terms of the ratio are
supposed to be.
第二に、資本の限界効率は絶対的な数量なのか、それとも比率なのかという問題がある。資本の限界効率が使われる文脈を見ても、それが利子率と同じ性質をも
つものとして扱う習慣から見ても、資本の限界効率は比率であると考えるべきである。ところが、この比率が何と何の比率なのかは一般には明らかにされていな
い。
Finally, there is the distinction, the neglect of which has been the
main cause of confusion and misunderstanding, between the increment of
value obtainable by using an additional quantity of capital in the
existing situation, and the series of increments which it is expected
to obtain over the whole life of the additional capital asset; ― i.e.
the distinction between Q1 and the complete series Q1, Q2, ... Qr ...
This involves the whole question of the place of expectation in
economic theory. Most discussions of the marginal efficiency of capital
seem to pay no attention to any member of the series except Q1. Yet
this cannot be legitimate except in a static theory, for which all the
Q's are equal. The ordinary theory of distribution, where it is assumed
that capital is getting now its marginal productivity (in some sense or
other), is only valid in a stationary state. The aggregate current
return to capital has no direct relationship to its marginal
efficiency; whilst its current return at the margin of production (i.e.
the return to capital which enters into the supply price of output) is
its marginal user cost, which also has no close connection with its
marginal efficiency.
最後に、現状に対して資本を追加することで得られる追加の価値と、追加の資本が廃棄されるまでにその資本から得られると予想される一連の追加価値との区
別、即ち、単独のＱ１と一連のＱ１、Ｑ２...Ｑｒ...の全体との区別がなされていないことから、混乱と誤解が生まれている。この区別は経済理論におけ
る予想の位置付けという問題の全体を含んでいるのである。資本の限界効率に関するこれまでの議論は、この一連のＱｒではなくＱ１にしか注目して来なかった
と思われる。しかし、これがうまくいくのはすべてのＱが同じ値である静的な理論だけである。資本は（ある意味での）限界生産力を今現在持っているとする一
般的な分配理論は、定常的な状況でのみ有効である。資本に対する現在の総収益は、資本の限界効率とは何の直接的関係もない。一方、資本の限界生産物におけ
る現在の収益（つまり産出物の供給価格に含まれる資本の収益）は資本の限界使用費用であって、これもまた資本の限界効率とは何の関係もない。
There is, as I have said above, a remarkable lack of any clear account
of the matter. At the same time I believe that the definition which I
have given above is fairly close to what Marshall intended to mean by
the term. The phrase which Marshall himself uses is “marginal net
efficiency” of a factor of production; or, alternatively, the “marginal
utility of capital”. The following is a summary of the most relevant
passage which I can find in his Principles (6th ed. pp. 519-520). I
have run together some non-consecutive sentences to convey the gist of
what he says:
上で言ったように、この問題に対する明確な説明が著しく欠けているのである。それにも関わらず、私が上記で示した定義はマーシャルが意図しているものに非
常に近いと思う。マーシャルが使っている言葉は生産要素の「限界純効率」かあるいは「資本の限界効用」である。次に文章は彼の『経済原理』（第６版５１９
頁ー５２０頁）の中の関連する箇所の要約で、彼の言わんとする要点を伝えるためにばらばらの文章をつなげたものである。
“In a certain factory an extra ￡100 worth of machinery can be applied
so as not to involve any other extra expense, and so as to add annually
￡3 worth to the net output of the factory after allowing for its own
wear and tear. If the investors of capital push it into every
occupation in which it seems likely to gain a high reward; and if,
after this has been done and equilibrium has been found, it still pays
and only just pays to employ this machinery, we can infer from this
fact that the yearly rate of interest is 3 per cent. But illustrations
of this kind merely indicate part of the action of the great causes
which govern value. They cannot be made into a theory of interest, any
more than into a theory of wages, without reasoning in a circle. ...
Suppose that the rate of interest is 3 per cent. per annum on perfectly
good security（証券）; and that the hat-making trade absorbs a capital of
one million pounds. This implies that the hat-making trade can turn the
whole million pounds' worth of capital to so good account（利用する） that
they would pay 3 per cent. per annum net for the use of it rather than
go without any of it. There may be machinery which the trade would have
refused to dispense with if the rate of interest had been 20 per cent.
per annum. If the rate had been 10 per cent., more would have been
used; if it had been 6 per cent., still more; if 4 per cent. still
more; and finally the rate being 3 per cent., they use more still. When
they have this amount, the marginal utility of the machinery i.e. the
utility of that machinery which it is only just worth their while to
employ, is measured by 3 per cent.”
「ある工場で１００ポンドの価値のある機械を追加して、それ以上の追加費用なしに作動させると、機械の損耗を差し引いた後の純産出量が毎年３ポンド分ずつ
増えるものとする。もし投資家が高い収益を見込めるあらゆる業種に投資して、それによって均衡がもたらされた後に、この機械を使用してもなおぎりぎりで損
が出なかったとすると、この事実からその年の利子率は年３％だったと推測できる（＝資本の限界効率が年利と同じだった）。しかし、この種の例が示している
のは市場における価値を左右する大きな要因のごく一部である。この例から利子率の理論や賃金の理論を作ろうとしても循環論に陥るだけである。・・・完璧に
優良な債券の年利が３％であり、帽子会社に１００万ポンドの投資が行われたとすると、それは帽子会社がその１００万ポンドの資本（＝機械）を放置すること
なくちゃんと全部使えば年３％の純利益を出せるということである。たとえ利子率が年２０％でも業者が使わないではいられない機械というものがある。それが
利子率１０％ならもっと多くの機械が使われる。それが利子率６％ならもっと使われる。利子率４％ならもっとである。だから利子率３％ならさらに多くの機械
が使われるようになる。ということは、彼らがこれだけの機械をもっている時、この機械の限界効用、即ち使用してもぎりぎり損が出ない機械の効用は３％なの
である」
It is evident from the above that Marshall was well aware that
we are involved in a circular argument if we try to determine along
these lines what the rate of interest actually is.[2] In this passage
he appears to accept the view set forth above, that the rate of
interest determines the point to which new investment will be pushed,
given the schedule of the marginal efficiency of capital. If the rate
of interest is 3 per cent., this means that no one will pay ￡100 for a
machine unless he hopes thereby to add ￡3 to his annual net output
after allowing for costs and depreciation. But we shall see in Chapter
14 that in other passages Marshall was less cautious ― though still
drawing back when his argument was leading him on to dubious ground.
ここからマーシャルはこの議論によって現実の利子率を決めようとすると循環論に陥るということを知っていたことは明らかである[２]。この文章において、
資本の限界効率表が与えられている時に新投資がどこまで押し進められるかは利子率によって決まるという上記の考え方を彼は受け入れていると思われる。つま
り、利子率が３％ということは、ある機械に１００ポンドを支払うのは、費用と減価償却を引いたその機械による純産出がそれによって毎年３ポンドずつ増える
と予想できる場合だけだということを意味しているのである。しかし、第１４章で見るように、マーシャルは別の箇所でもう少し大胆になっている。ただし議論
がはっきりしないところに行くと後退ぎみであるが。
Although he does not call it the “marginal efficiency of capital”,
Professor Irving Fisher has given in his Theory of Interest (1930) a
definition of what he calls “the rate of return over cost” which is
identical with my definition. “The rate of return over cost”, he
writes,[3] “is that rate which, employed in computing the present worth
of all the costs and the present worth of all the returns, will make
these two equal.” Professor Fisher explains that the extent of
investment in any direction will depend on a comparison between the
rate of return over cost and the rate of interest. To induce new
investment “the rate of return over cost must exceed the rate of
interest”.[4] “This new magnitude (or factor) in our study plays the
central role on the investment opportunity side of interest theory.”
[5] Thus Professor Fisher uses his “rate of return over cost” in the
same sense and for precisely the same purpose as I employ “the marginal
efficiency of capital”.
アーヴィング・フィッシャー教授も「資本の限界効率」という呼び方はしないが、「費用超過収益率」と呼ぶものの定義を『利子率の理論』（１９３０年）のな
かで行なっているが、私の定義と同じである。「費用超過収益率は、総費用の現在価値と総収益の現在価値を計算するときに使われるもので、この２つのものを
同じ値にする比率である」と彼は書いている[３]。フィッシャー教授の説明では、どの分野であろうと投資のレベルは費用超過収益率と利子率との比較に依存
している。新投資を引き出すためには「費用超過収益率が利子率を超えなければならない」[４]。「我々の研究の中ではこの変数（あるいは要素）は投資機会
に関する利子理論において中心的な役割を果たしている」[５]。つまり、フィッシャー教授は「費用超過収益率」を「資本の限界効率」と同じ意味と同じ目的
で使っているのである。
III
The most important confusion concerning the meaning and
significance of the marginal efficiency of capital has ensued on the
failure to see that it depends on the prospective yield of capital, and
not merely on its current yield. This can be best illustrated by
pointing out the effect on the marginal efficiency of capital of an
expectation of changes in the prospective cost of production, whether
these changes are expected to come from changes in labour cost, i.e. in
the wage-unit, or from inventions and new technique. The output from
equipment produced to-day will have to compete, in the course of its
life, with the output from equipment produced subsequently, perhaps at
a lower labour cost, perhaps by an improved technique, which is content
with a lower price for its output and will be increased in quantity
until the price of its output has fallen to the <lowest>[lower
仏訳より] figure with which it is content. Moreover, the entrepreneur's
profit (in terms of money) from equipment, old or new, will be reduced,
if all output comes to be produced more cheaply. In so far as such
developments are foreseen as probable, or even as possible, the
marginal efficiency of capital produced to-day is appropriately
diminished.
第３節
資本の限界効率の意味に関して最も重大な混乱は、それが予想収益に依存しているのであって、単に現在の収益に依存しているのではないということが理解でき
ないことから来ている。生産費用の変化の予想が資本の限界効率に与える効果を指摘するのが、この違いを最もよく説明できるだろう。生産費用の変化は労働コ
スト即ち単位賃金の変化から来たり技術革新から来ると予想されている。今日作られた設備からの産出物はその設備の寿命の間、恐らくもっと低い労働コストと
もっと優れた技術で後日作られた設備から生まれる産出物と競争することになる。しかも、新しい設備は産出物の価格が安くても操業できるし、その設備は大量
に作られて産出物の価格が最低ラインにまで下がるのである。さらに、全ての産出物がもっと安く生産されるようになると、新旧の設備から得られる企業家の利
益（貨幣で測った）は減少する。そのような展開が充分予想される場合には、今日作られた資本設備の限界効率は減少するのである（＝資本の限界効率のグラフ
は右下がりになる）。
This is the factor through which the expectation of changes in
the value of money influences the volume of current output. The
expectation of a fall in the value of money stimulates investment, and
hence employment generally, because it raises the schedule of the
marginal efficiency of capital, i.e. the investment demand-schedule;
and the expectation of a rise in the value of money is depressing,
because it lowers the schedule of the marginal efficiency of capital.
この要因があるから、貨幣価値の変化（＝物価）の予想が当期の産出量に影響するである。貨幣価値の下落（＝物価の上昇）の予想は投資を刺激して雇用を増加
する。なぜなら、資本の限界効率表即ち投資需要表を上にシフトさせるからである。貨幣価値の上昇（＝物価の下落）の予想は投資を抑制する。なぜなら、それ
は資本の限界効率表を下にシフトさせるからである。
This is the truth which lies behind Professor Irving Fisher's
theory of what he originally called “Appreciation and Interest” ― the
distinction between the money rate of interest and the real rate of
interest where the latter is equal to the former after correction for
changes in the value of money. It is difficult to make sense of this
theory as stated, because it is not clear whether the change in the
value of money is or is not assumed to be foreseen. There is no escape
from the dilemma that, if it is not foreseen, there will be no effect
on current affairs; whilst, if it is foreseen, the prices of existing
goods will be forthwith（直ちに） so adjusted that the advantages of holding
money and of holding goods are again equalised, and it will be too late
for holders of money to gain or to suffer a change in the rate of
interest which will offset the prospective change during the period of
the loan in the value of the money lent. For the dilemma is not
successfully escaped by Professor Pigou's expedient of supposing that
the prospective change in the value of money is foreseen by one set of
people but not foreseen by another.
この事実こそはアーヴィン・フィッシャー教授の『価値の騰貴と利子』の理論の背後にあるものである。この理論は貨幣利子率と実質利子率の区別に関するもの
で、後者は前者を貨幣価値変動分（＝物価変動分）だけ修正した値である。彼の理論をそのままの形で理解するのは容易ではない。というのは、貨幣価値（＝物
価）の変化は予想できると見なすのかどうかが明らかでないからである。もし貨幣価値の変化が予想できないなら、貨幣価値の将来の変化は現状に対して何の影
響力もない。しかし、もし予想できるなら、現在の財（＝債券）の価格はその予測によって直ちに調整されて、貨幣を保有する利益と財を保有する利益は再びイ
コールになってしまう。貨幣の保有者は利子率の変化によって損をしたり得をしたりする時間はない。利子率は、貸出し期間内に予想される貸出し貨幣の価値
（＝物価）の変化を相殺するように変化するものだからである。誰もこのジレンマを逃れることは出来ない。ピグー教授のように貨幣価値の将来の変化は予測で
きる人とできない人がいると考えても、それでこのジレンマをうまく逃れることは出来ないのである。
The mistake lies in supposing that it is the rate of interest on
which prospective changes in the value of money will directly
react（反作用を及ぼす）, instead of the marginal efficiency of a given stock of
capital. The prices of existing assets will always adjust themselves to
changes in expectation concerning the prospective value of money. The
significance of such changes in expectation lies in their effect on the
readiness to produce new assets through their reaction on the marginal
efficiency of capital. The stimulating effect of the expectation of
higher prices is due, not to its raising the rate of interest (that
would be a paradoxical way of stimulating output ― in so far as the
rate of interest rises, the stimulating effect is to that extent
offset), but to its raising the marginal efficiency of a given stock of
capital. If the rate of interest were to rise pari passu with the
marginal efficiency of capital, there would be no stimulating effect
from the expectation of rising prices. For the stimulus to output
depends on the marginal efficiency of a given stock of capital rising
relatively to the rate of interest. Indeed Professor Fisher's theory
could be best re-written in terms of a “real rate of interest” defined
as being the rate of interest which would have to rule, consequently on
a change in the state of expectation as to the future value of money,
in order that this change should have no effect on current output.[6]
フィッシャー教授の間違いの原因は、貨幣価値（＝物価）の将来の変化が資本の限界効率ではなく直接利子率に反作用を及ぼすと考えるところにある。現在の資
産の価格は常に将来の貨幣価値の予想の変化に合わせて変化する。そのような予想の変化の意義は、その変化が資本の限界効率に与える作用を通じて、新たな設
備を作ろうとする気持ちに影響をすることにある。物価上昇（＝貨幣価値の下落）の予想が設備を作る気持ちを促すのは、その予想が利子率を引き上げる（利子
率の引上げは産出量を刺激する通常の方法ではない。利子率が上がると刺激効果はその分だけ相殺されるからである）からではなく、資本の限界効率を引き上げ
るからである。もし利子率が資本の限界効率と足並みを揃えて上昇するなら、物価上昇の予想からの刺激的効果は全く生まれない。というのは、産出量に対する
刺激は、資本の限界効率が利子率より高いことから生れるからである。実際、フィッシャー教授の理論は、「実質利子率」を「将来の貨幣価値（＝物価）の予想
の変化に応じて、この変化が当期の産出量に与える影響を相殺するように働く利子率」のことだと定義してから書き直すべきだろう[６]。
It is worth noting that an expectation of a future fall in the
rate of interest will have the effect of lowering the schedule of the
marginal efficiency of capital; since it means that the output from
equipment produced to-day will have to compete during part of its life
with the output from equipment which is content with a lower return.
This expectation will have no great depressing effect, since the
expectations, which are held concerning the complex of rates of
interest for various terms which will rule in the future, will be
partially reflected in the complex of rates of interest which rule
to-day. Nevertheless there may be some depressing effect, since the
output from equipment produced to-day, which will emerge towards the
end of the life of this equipment, may have to compete with the output
of much younger equipment which is content with a lower return because
of the lower rate of interest which rules for periods subsequent to the
end of the life of equipment produced to-day.
将来の利子率が下落することが予想されると、資本の限界効率表（＝グラフ）は下にシフトする、ということは明記するに値する。というのは、これは今日作ら
れた設備からの産出物はその設備の寿命の間もっと低い利益で操業できる設備の産出物と競争しなければならないことを意味するからである。将来の利子率の下
落の予想（＝貨幣価値は上がる）には投資を抑制するそれほど大きな効果はない。というのは、様々な満期をもつ将来の利子率複合体に関する予想は今日の利子
率複合体に部分的に反映されるからである。それでも、利子率の下落の予想にはいくらか抑制効果はあるものだ。というのは、今日作られた設備からその寿命の
最後に生まれる産出物は、もっと新しい設備からの産出物と競争しなければならないが、新しい設備は今日作られた設備の寿命の最後の頃の低い利子率のおかげ
で低い利益で操業できるからである。
It is important to understand the dependence of the marginal
efficiency of a given stock of capital on changes in expectation,
because it is chiefly this dependence which renders the marginal
efficiency of capital subject to the somewhat violent fluctuations
which are the explanation of the Trade Cycle. In Chapter 22 below we
shall show that the succession of Boom and Slump can be described and
analysed in terms of the fluctuations of the marginal efficiency of
capital relatively to the rate of interest.
資本ストックの限界効率が予想の変化に依存することを理解するのは重要である。というのは、予想に依存するがゆえに資本の限界効率は大きな変動にさらされ
ざるを得ないのであり、それが景気循環を説明しているのである。のちに第２２章では、資本の限界効率の利子率に対する変動の見地から好景気と不景気の継起
を分析説明するつももりである。
IV
Two types of risk affect the volume of investment which have not
commonly been distinguished, but which it is important to distinguish.
The first is the entrepreneur's or borrower's
risk（企業家、企業家側のリスク、借り入れ側のリスク）and arises out of doubts in his own mind as
to the probability of his actually earning the prospective yield for
which he hopes. If a man is venturing his own money, this is the only
risk which is relevant.
第４節 リスクについて
一般には区別されていないけれども、投資に影響するリスクには２つのタイプがあって、これを区別することは重要である。一つ目のタイプのリスクは企業家の
リスクつまり借り手のリスクである。これは彼が望む予想収益が実際に得られるかどうかの確実性に関する心理的な不安から来るリスクである。もしこれが自分
の金の投資なら（＝内部金融）、リスクはこれで全てである。
But where a system of borrowing and lending exists, by which I mean the
granting of loans with a margin（能力、余力、余裕） of real or personal
security（担保）, a second type of risk is relevant which we may call the
lender's risk（貸し手側のリスク）. This may be due either to moral hazard, i.e.
voluntary default or other means of escape, possibly lawful, from the
fulfilment of the obligation（債務の履行）, or to the possible insufficiency
of the margin of security（担保不足）, i.e. involuntary default due to the
disappointment of expectation. A third source of risk might be added,
namely, a possible adverse change in the value of the monetary standard
which renders a money-loan to this extent less secure than a real
asset; though all or most of this should be already reflected, and
therefore absorbed, in the price of durable real assets.
ところが、貸し借りの制度があって、物的担保や人的担保に対して融資する場合には、貸し手のリスクと呼ばれる二つ目のリスクが関係してくる。このリスクは
道義的リスクつまり意図的な破産や債務履行の合法的な回避によるものか、あるいは、担保不足による回収不能の可能性、つまり予想外れに起因する不本意な破
産によるものである。三つ目のリスクがあるとすれば、それは貨幣価値の不利な変化であろう。これは現物資産よりは金銭ローンを不安定にする。ただし、貨幣
価値の変化は耐久実物資産の価格に反映してそこに吸収されてしまう。
Now the first type of risk is, in a sense, a real social
cost（社会的費用）, though susceptible to diminution by averaging
（難平、リスクを平均化すること）as well as by an increased accuracy of foresight. The
second, however, is a pure addition to the cost of investment which
would not exist if the borrower and lender were the same person.
Moreover, it involves in part a duplication of a proportion（一部） of the
entrepreneur's risk, which is added twice to the pure rate of interest
to give the minimum prospective yield which will induce the investment.
ところで、一つ目のリスクはある意味で真の社会的費用である。この場合は、予測の精度を高めたりリスクを平均化したりすることでリスクの軽減化が可能であ
る。それに対して、二つ目のリスクは投資費用への純粋な追加の費用で、これは借り手と貸し手が同じ人間なら発生しないものである。さらに、この二つ目のリ
スクには企業家のリスクの一部が重複して含まれている。つまり、投資の誘引となる最小予想収益を決めるさいに、純粋利子率（＝安全資産の利子率）に対して
企業家つまり借り手のリスクの一部が二度足し算されるのである。
For if a venture is a risky one, the borrower will require a
wider margin（上乗せ） between his expectation of yield and the rate of
interest at which he will think it worth his while to borrow; whilst
the very same reason will lead the lender to require a wider
margin（利ざや、上乗せ） between what he charges and the pure rate of
interest（純粋利子率） in order to induce him to lend (except where the
borrower is so strong and wealthy that he is in a position to offer an
exceptional margin of security（借り手の担保能力）). The hope of a very
favourable outcome, which may balance the risk in the mind of the
borrower, is not available to solace the lender.
というのは、もし事業がリスクのあるものなら（＝借り手のリスク）、借り手は借金してもよいと考える利子率（＝借入利子率＝貸出利子率＋借り手のリスクプ
レミアム）と予想収益率との差が、事業のリスク分だけ大きくなることを求めるからであり、同じ理由で、貸し手側も彼が金を貸す気になるためには、自分が要
求する利子率（＝貸出利子率＝純粋利子率＋貸し手のリスクプレミム）と純粋利子率との差がその事業のリスク分だけ大きくなることを求めるからである（もち
ろん借り手が大金持ちで例外的に大きな担保能力がある場合は別である）。借り手側が自分の感じているリスクを相殺するような好結果を予測したところで、そ
れは貸し手側にとっては何の慰めにもならないからである（＝だから、貸し手にも借り手のリスクが影響する）。（『図解雑学ケインズ経済学』ｐ１２４参照）
This duplication of allowance for a portion of the risk has not
hitherto been emphasised, so far as I am aware; but it may be important
in certain circumstances. During a boom the popular estimation of the
magnitude of both these risks, both borrower's risk and lender's risk,
is apt to become unusually and imprudently low.
リスクの一部がこのように重複して足算されていることは、私の知る限り、これまで強調されることはなかったが、一定の状況では重要であるかもしれない。好況時にはこれらの二つのリスクの大きさに対する一般の評価は無謀なまでに低くなりがちである。
V
The schedule of the marginal efficiency of capital is of fundamental
importance because it is mainly through this factor (much more than
through the rate of interest) that the expectation of the future
influences the present. The mistake of regarding the marginal
efficiency of capital primarily in terms of the current yield of
capital equipment, which would be correct only in the static state
where there is no changing future to influence the present, has had the
result of breaking the theoretical link between to-day and to-morrow.
Even the rate of interest is, virtually,[7] a current phenomenon; and
if we reduce the marginal efficiency of capital to the same status, we
cut ourselves off from taking any direct account of the influence of
the future in our analysis of the existing equilibrium.
資本の限界効率表は非常に重要である。なぜなら、将来に対する予想が現在に影響するのは（利子率ではなく）主にこの資本の限界効率という要因だからであ
る。資本の限界効率を現在の資本の収益率によって考えることは間違っている。それが正しいのは将来が現在に何の影響も及ぼさない静的な状態だけであって、
今日と明日を結ぶ理論的な糸を断ち切ってしまうことになる。利子率でさえもほとんど[７]現在の現象なのだ。もし資本の限界効率を利子率と同じ位置に置い
てしまうならば、現在の均衡分析の際に未来がもっている影響を考慮することが出来なくなってしまう。
The fact that the assumptions of the static state often underlie
present-day economic theory, imports into it a large element of
unreality. But the introduction of the concepts of user cost and of the
marginal efficiency of capital, as defined above, will have the effect,
I think, of bringing it back to reality, whilst reducing to a minimum
the necessary degree of adaptation.
静的な状態を想定することが現代の経済理論の基本になっていて、それが現代の経済理論を非現実的なものにしている。それに対して、私の考えでは、上記で説
明したような使用費用と資本の限界効率という概念を導入するという最低限の修正を加えることで、現代の経済理論を現実味を持ったものに戻すことが出来る。
It is by reason of the existence of durable equipment that the
economic future is linked to the present. It is, therefore, consonant
with, and agreeable to, our broad principles of thought, that the
expectation of the future should affect the present through the demand
price for durable equipment.
耐久設備の存在することが経済の未来を現在に結びつけているのである。だから、将来に対する予想は耐久設備の需要価格を通じて現在に影響を及ぼすといっても、我々の考え方と概ね大差はない。
Author's Footnotes
[1]. For the sake of simplicity of statement I have slurred（見逃す） the
point that we are dealing with complexes of rates of interest
（利子率複合体）and discount corresponding to the different lengths of time
which will elapse before the various prospective returns from the asset
are realised. But it is not difficult to re-state the argument so as to
cover this point.
[2]. But was he not wrong in supposing that the marginal productivity theory of wages is equally circular?
[3]. Op. cit. p. 168
[4]. Op. cit. p. 159.
[5]. Op. cit. p. 155.
[6]. Cf. Mr. Robertson's article on “Industrial Fluctuations and the Natural Rate of Interest”, Economic Journal, December 1934.
[7]. Not completely; for its value partly reflects the uncertainty of
the future. Moreover, the relation between rates of interest for
different terms depends on expectations.
著者注
[１] 叙述の単純化のために、ここで扱っているのが利子率と割引率の複合体であるという点は考慮に入れなかった。それらの利率は資産の様々な予想収益が
実現する迄に過ぎるべき時間の様々な長さに応じて異なっている。この点までの含めた議論にして書きなおすのは難しいことではない。
[２] しかし、マーシャルが賃金の限界生産性の理論も同様に循環理論になると考えているのは間違っているのではなかろうか。
[３] 前掲書１６８頁
[４] 前掲書１５９頁
[５] 前掲書１５５頁
[６] ロバートソン氏の論文『産業変動と自然利子率』（『エコノミック・ジャーナル』１９３４年１２月号）参照。
[７] 完全にではない。というのは、利子率の値は未来の不確実性を一部反映しているからである。さらに、様々な期間の利子率どうしの関係も予想に依存している。
Chapter 12. The State of Long-Term Expectation
第１２章 長期予想
I
WE have seen in the previous chapter that the scale of investment
depends on the relation between the rate of interest and the schedule
of the marginal efficiency of capital corresponding to different scales
of current investment, whilst the marginal efficiency of capital
depends on the relation between the supply price of a capital-asset and
its prospective yield. In this chapter we shall consider in more detail
some of the factors which determine the prospective yield of an asset.
前の章で我々は投資の規模は利子率と資本の限界効率表（現在の投資の様々規模に対応する）との関係に依存し、資本の限界効率は資本資産の供給価格とその予想収益との関係に依存することを見た。この章では資産の予想収益を決定する要素の幾つかを詳しく検討していこう。
The considerations upon which expectations of prospective yields are
based are partly existing facts which we can assume to be known more or
less for certain, and partly future events which can only be forecasted
with more or less confidence.
将来の収益を予想する際に材料とすべき検討対象は、一つには現在の確かな事実があり、一つには確信度を持って推測できる将来の出来事がある。
Amongst the first may be mentioned the existing stock of various types
of capital-assets and of capital-assets in general and the strength of
the existing consumers' demand for goods which require for their
efficient production a relatively larger assistance from capital.
Amongst the latter are future changes in the type and quantity of the
stock of capital-assets and in the tastes of the consumer, the strength
of effective demand from time to time during the life of the investment
under consideration, and the changes in the wage-unit in terms of money
which may occur during its life. We may sum up the state of
psychological expectation which covers the latter as being the state of
long-term expectation; ― as distinguished from the short-term
expectation upon the basis of which a producer estimates what he will
get for a product when it is finished if he decides to begin producing
it to-day with the existing plant, which we examined in Chapter 5.
前者としては、様々なタイプの資本資産のストック、資本資産一般のストック、財に対する現在の消費者の需要の強さ、つまり効率的な生産のために資本のテコ
入れを必要としているほど需要があることがあげられる。後者としては、将来における資本資産ストックの量とタイプの変化、消費者の好みの変化、投資財が廃
棄されるまでの時々刻々の有効需要の強さ、その期間における貨幣で測った単位賃金の変化である。この後者に含まれる心理的な予想を長期予想と要約すること
ができる。それに対して短期予想は第５章ですでに扱ったように、それをもとに生産者は現行プラントで今日生産を始めてそれが完成した時にその製品からいく
ら利益が得られるかを推測するのである。
II
It would be foolish, in forming our expectations, to attach
great weight to matters which are very uncertain.[1] It is reasonable,
therefore, to be guided to a considerable degree by the facts about
which we feel somewhat confident, even though they may be less
decisively relevant to the issue than other facts about which our
knowledge is vague and scanty. For this reason the facts of the
existing situation enter, in a sense disproportionately, into the
formation of our long-term expectations; our usual practice being to
take the existing situation and to project it into the future, modified
only to the extent that we have more or less definite reasons for
expecting a change.
我々が物事の予想をするにあたって、全く不確かなことに重きをおくのは愚かなことである[１]。したがって、多くの場合ある程度確信の持てる事実を手引き
にするのが合理的である。たとえその方が他のもっと不確かであやふやな事実よりも問題に対する決定的な関わり度が低いとしてもである。そのために、長期予
想を形成するときには現在の状況を示す事実が不釣り合いなほど入り込んでくるものである。我々の普通の習慣は現在の状況から出発してそれを将来に投影する
のではあり、変化が予想できる確たる理由がある場合だけ、その習慣を修正するのである。
The state of long-term expectation, upon which our decisions are based,
does not solely depend, therefore, on the most probable
forecast（最も確実な予測） we can make. It also depends on the
confidence（企業家の確信） with which we make this forecast ― on how highly we
rate the likelihood of our best forecast turning out quite wrong. If we
expect large changes but are very uncertain as to what precise form
these changes will take, then our confidence will be weak.
したがって、我々の決断の根拠となる長期予想は単に最も確実な予測に依存するだけではない。長期予想は同時に、我々がこの予測を行う際の確信度（＝景気見
通し、投資意欲）にも依存している。つまり、それは最も確実な予測が外れる可能性がどの程度あると考えるかにも依存しているのでる。大きな変化が予測され
る時にその変化がどういう形をとるかについて確実でない時、我々の確信は弱まるのである。
The state of confidence（確信度）, as they term it, is a matter to which
practical men always pay the closest and most anxious attention. But
economists have not analysed it carefully and have been content, as a
rule, to discuss it in general terms. In particular it has not been
made clear that its relevance to economic problems comes in through its
important influence on the schedule of the marginal efficiency of
capital. There are not two separate factors affecting the rate of
investment, namely, the schedule of the marginal efficiency of capital
and the state of confidence. The state of confidence is relevant
because it is one of the major factors determining the former, which is
the same thing as the investment demand-schedule.
実務家がいう確信度は彼らが常に最も注目しているものである。しかし、経済学者たちはそれを丁寧に分析することなく大雑把に語るだけで満足してきた。特に
この確信の度合いは資本の限界効率表に大きな影響を与えて、それによって様々な経済問題に関わってくることは明らかにされて来なかった。資本の限界効率表
と確信度という二つの要素は、投資量に別々に影響するのではない。確信度は資本の限界効率表（これは投資需要表と同じものである）を決定する重要な要素の
一つであるがゆえに重要なのである。
There is, however, not much to be said about the state of confidence a
priori. Our conclusions must mainly depend upon the actual observation
of markets and business psychology. This is the reason why the ensuing
digression is on a different level of abstraction from most of this
book.
しかし、確信度について経験を離れて抽象的に言えることは多くない。我々の結論は現実の市場や経営心理の観察に基づかなければならない。そういうわけで、以下の脱線はこの本の多くの部分とは抽象レベルにおいて異なっている。
For convenience of exposition we shall assume in the following
discussion of the state of confidence that there are no changes in the
rate of interest; and we shall write, throughout the following
sections, as if changes in the values of investments were solely due to
changes in the expectation of their prospective yields and not at all
to changes in the rate of interest at which these prospective yields
are capitalised. The effect of changes in the rate of interest is,
however, easily superimposed on the effect of changes in the state of
confidence.
以下で行う確信度に関する議論では、話の便宜上利子率の変化はないものと仮定する。以下の節を通じて、投資の価値の変化はその予想収益の変化だけによって
起こり、その収益が資本化される時の利子率の変化には依らないものとする。しかし、利子率の変化の結果を確信度の変化の結果に追加するのは容易である。
III
The outstanding fact is the extreme precariousness of the basis
of knowledge on which our estimates of prospective yield have to be
made. Our knowledge of the factors which will govern the yield of an
investment some years hence is usually very slight and often
negligible. If we speak frankly, we have to admit that our basis of
knowledge for estimating the yield ten years hence of a railway, a
copper mine, a textile factory, the goodwill of a patent medicine, an
Atlantic liner, a building in the City of London amounts to little and
sometimes to nothing; or even five years hence. In fact, those who
seriously attempt to make any such estimate are often so much in the
minority that their behaviour does not govern the market.
特筆すべき事実は、未来の収益を評価する知識の基盤が極めてあやふやなことである。投資の数年後の利益を左右する要因について我々が知っていることは、普
通は非常に薄弱でとるに足らない事である。率直に言えば、鉄道にしろ銅山にしろ繊維工場にしろ特許薬の権利にしろ大西洋航路の定期船にしろロンドンのビル
にしろ、今から１０年後の収益を評価する知識の基盤はほぼゼロに等しいことを我々は認めなくてはならない。５年後でも同様である。実際、そのような評価を
真面目にしようとする人は非常に少数派なので、彼らの行動が市場を左右することはないのである。
In former times, when enterprises were mainly owned by those who
undertook them or by their friends and associates, investment depended
on a sufficient supply of individuals of sanguine temperament and
constructive impulses who embarked on business as a way of life, not
really relying on a precise calculation of prospective profit. The
affair was partly a lottery, though with the ultimate result largely
governed by whether the abilities and character of the managers were
above or below the average. Some would fail and some would succeed. But
even after the event no one would know whether the average results in
terms of the sums invested had exceeded, equalled or fallen short of
the prevailing rate of interest; though, if we exclude the exploitation
of natural resources and monopolies, it is probable that the actual
average results of investments, even during periods of progress and
prosperity, have disappointed the hopes which prompted them. Business
men play a mixed game of skill and chance, the average results of which
to the players are not known by those who take a hand. If human nature
felt no temptation to take a chance, no satisfaction (profit apart) in
constructing a factory, a railway, a mine or a farm, there might not be
much investment merely as a result of cold calculation.
昔のように企業が創業者とその仲間や友人たちのものだった時代には、投資は将来の利益の正確な計算にもとづいて行われるのではなく、人生の生き方として事
業に乗り出すような自信に満ちた前向きの人たちの行うことだった。もちろん、事業の結果は経営者の能力に大きく左右されたが、その一部は運任せだった。成
功する人もいれば失敗する人もいた。しかし、結果が出たあとで投資量と比べてそれが現行の利子率を上回っているか同じか下回っているかを誰も知ろうとはし
なかった。もっとも、自然資源の乱用や独占を例外とするかぎり、投資の平均的な結果は、繁栄と進歩の時代においても、最初の期待を裏切るものだった。経営
者たちは技術と運の入り混じったゲームをしているのであって、このゲームの平均的な結果をゲームの参加者は知らないのである。もし人間の本姓が一か八かの
運試しに対して何の誘惑も感じず、工場や鉄道や鉱山や農場の建設に対して利益以外の喜びを全く感じないとしたら、冷静な計算の結果としての投資はそれほど
行われないかもしれない。
Decisions to invest in private business of the old-fashioned
type were, however, decisions largely irrevocable, not only for the
community as a whole, but also for the individual. With the separation
between ownership and management which prevails to-day and with the
development of organised investment markets, a new factor of great
importance has entered in, which sometimes facilitates investment but
sometimes adds greatly to the instability of the system. In the absence
of security markets, there is no object in frequently attempting to
revalue an investment to which we are committed. But the Stock Exchange
revalues many investments every day and the revaluations give a
frequent opportunity to the individual (though not to the community as
a whole) to revise his commitments. It is as though a farmer, having
tapped his barometer after breakfast, could decide to remove his
capital from the farming business between 10 and 11 in the morning and
reconsider whether he should return to it later in the week.
しかし、古いタイプの民間事業に対して投資する決断は、社会全体にとっても個人にとっても大抵は取り消しがきかなかった。今日のようにオーナーと経営者が
別になり、投資市場が組織されてからは、新たに非常に重要な要素が加わった。それはしばしば投資を容易にしたが、同時にしばしば制度をひどく不安定にし
た。株式市場がなければ，自分の関わっている投資物件を頻繁に再評価をしようとしても無駄である。しかし、株式市場は多くの投資物件を日々再評価してお
り、その再評価のおかげで個人（社会全体ではない）は自分の投資先を変更する機会を頻繁に与えられる。それはまるで農家が朝食後に晴雨計をチェックして、
農業ビジネスから自分の資本を午前１０時と１１時の間に引き上げることを決めて、その週の後半にまた農業ビジネスに戻るかどうか再考できるかのようであ
る。
But the daily revaluations of the Stock Exchange, though they are
primarily made to facilitate transfers of old investments between one
individual and another, inevitably exert a decisive influence on the
rate of current investment. For there is no sense in building up a new
enterprise at a cost greater than that at which a similar existing
enterprise can be purchased; whilst there is an inducement to spend on
a new project what may seem an extravagant sum, if it can be floated
off（市場で売りに出す） on the Stock Exchange at an immediate profit.[2] Thus
certain classes of investment are governed by the average expectation
of those who deal on the Stock Exchange as revealed in the price of
shares, rather than by the genuine expectations of the professional
entrepreneur.[3] How then are these highly significant daily, even
hourly, revaluations of existing investments carried out in practice?
しかし、株式市場の毎日の再評価は主に古い投資を個人の間で移動しやすくするために行われているのであるが、それが現在の投資量に決定的な影響を及ぼすこ
とは避けがたい。というのは、今ある企業を安い値段で買えるのに、同種の企業を新たに高い値段で作るのは馬鹿げているからである。その一方、もし新しいプ
ロジェクトを株式市場で売りに出せばすぐに利益が得られるなら、そのプロジェクトに莫大な金を出資するインセンティブが生まれる[２]。つまり、ある種の
投資物件の部門は、プロの企業家の本心から立てた予想によってではなく、株価という形で表れる株式仲買人たちの平均的な思惑によって左右されるのである
[３]。では今ある投資物件にとって重要な意味を持つ毎日の、いや毎時刻の再評価はどのようにして行われるのだろうか。
IV
In practice we have tacitly agreed, as a rule, to fall back on
what is, in truth, a convention. The essence of this convention ―
though it does not, of course, work out quite so simply ― lies in
assuming that the existing state of affairs will continue indefinitely,
except in so far as we have specific reasons to expect a change. This
does not mean that we really believe that the existing state of affairs
will continue indefinitely. We know from extensive experience that this
is most unlikely. The actual results of an investment over a long term
of years very seldom agree with the initial expectation. Nor can we
rationalize our behaviour by arguing that to a man in a state of
ignorance errors in either direction are equally probable, so that
there remains a mean actuarial expectation based on equi-probabilities.
実際問題として、概して我々は「慣習」となっている事（＝平均的人間が平均的にやっていること）に頼ることに暗黙のうちに一致している。この慣習の核心
は、もちろんそれほど単純に作用することはないが、変化が予測される明確な理由が存在しない場合には、現状がいつまでも続くと考えることである。これは我
々が現状がいつまでも続くと信じているということではない。そんなことはないのを我々は豊かな経験から知っている。長い年月の後の投資の結果が当初の予想
通りにはなることは滅多にないからである。かといって、無知の状態の置かれた人間にとってどの方向に間違うのも同じ位あり得ることだから、同じ確率に基づ
いて統計的に平均を予測するしかないと言って、我々の行動（＝慣習に従うこと）を正当化することは出来ない。
For it can easily be shown that the assumption of arithmetically equal
probabilities based on a state of ignorance leads to absurdities. We
are assuming, in effect, that the existing market valuation, however
arrived at, is uniquely correct in relation to our existing knowledge
of the facts which will influence the yield of the investment, and that
it will only change in proportion to changes in this knowledge; though,
philosophically speaking, it cannot be uniquely correct, since our
existing knowledge does not provide a sufficient basis for a calculated
mathematical expectation. In point of fact, all sorts of considerations
enter into the market valuation which are in no way relevant to the
prospective yield.
というのは、容易に示すことができるように、無知を元にした数理的確率が同じだと考えるのは馬鹿げたことだからである。実際、我々の想定では、現在の市場
の評価が正しいのは、それがどのようにして手に入れたものであっても、投資の利益に影響する事についての今の知識とつながっているからであり、市場の評価
が変わるのはこの知識に変化があるときだけである。もっとも、厳密に言うなら、数理的に計算された予測を我々の今の知識だけから出すのは不充分だから、そ
れだけが正しいとは言えない。事実、予想収益とは何の関係もないあらゆる検討材料が市場の評価に関係しているのである。
Nevertheless the above conventional method of calculation will be
compatible with a considerable measure of continuity and stability in
our affairs, so long as we can rely on the maintenance of the
convention.
それにも関わらず、この慣習（＝平均的人間の平均的行動）の継続を当てに出来る場合には、平均を予測する上記の慣習的な計算方法は、我々の様々な事業のかなりのレベルの継続性と安定性との間に齟齬をきたすことはないだろう。
For if there exist organised investment markets and if we can rely on
the maintenance of the convention, an investor can legitimately
encourage himself with the idea that the only risk he runs is that of a
genuine change in the news（情勢） over the near future, as to the
likelihood of which he can attempt to form his own judgment, and which
is unlikely to be very large. For, assuming that the convention holds
good, it is only these changes which can affect the value of his
investment, and he need not lose his sleep merely because he has not
any notion what his investment will be worth ten years hence. Thus
investment becomes reasonably “safe” for the individual investor over
short periods, and hence over a succession of short periods however
many, if he can fairly rely on there being no breakdown in the
convention and on his therefore having an opportunity to revise his
judgment and change his investment, before there has been time for much
to happen. Investments which are “fixed” for the community are thus
made “liquid” for the individual.
というのは、組織された投資市場が存在して、慣習の継続を当てに出来るなら、投資家は当然のことながら自分が冒す唯一のリスクは近い将来に関する情勢の明
らかな変化だけと考えて安心することが出来るからである。なぜなら、そのようなリスクの可能性については自分で判断できるし、それほど大きなリスクではな
さそうだからである。というのは、慣習が続いているなら、そのような変化だけが投資の価値に影響があるし、１０年後の自分の投資の価値がいくらになるか分
からないといってやきもきする必要はないからである。こうして、投資は短期においては個人投資家にとってかなり安全なものとなるのである。慣習の継続を当
てに出来て、自分の判断を変えることが出来て、色んな事が起きる前に投資先を変えられるなら、その後の短期の繰り返しの中でも同様に安全である。社会に
とって固定している投資はこうして個人（＝投資家）にとっては流動的なものになるのである。
It has been, I am sure, on the basis of some such procedure as
this that our leading investment markets have been developed. But it is
not surprising that a convention, in an absolute view of things so
arbitrary, should have its weak points. It is its precariousness which
creates no small part of our contemporary problem of securing
sufficient investment.
このように進み方で我々の主な投資市場は発展してきたと私は信じている。ところが、慣習はそれ自体としてみれば根拠が薄弱なものなので、それなりの弱点が
あることは驚くべきことではない。その弱点とは不安定なことである。そして充分な投資を確保するという現代の我々の問題の多くの部分は、慣習の不安定さの
ために生み出されているのである。
V
Some of the factors which accentuate this precariousness may be briefly mentioned.
慣習のこのうつろいやすさを加速する要因の幾つかをここで簡単にあげておこう。
(1) As a result of the gradual increase in the proportion of the equity
in the community's aggregate capital investment which is owned by
persons who do not manage and have no special knowledge of the
circumstances, either actual or prospective, of the business in
question, the element of real knowledge in the valuation of investments
by those who own them or contemplate purchasing them has seriously
declined.
（１）社会の総資本投資のうちで経営者でない人たちが所有する株式の割合が次第に増えているが、彼らには当該事業の現在ないし将来の状況に関する専門的知
識がないので、投資物件の所有者や所有を検討している人たちが投資物件を評価するときに、しっかりした知識が不足するようになっていること。
(2) Day-to-day fluctuations in the profits of existing investments,
which are obviously of an ephemeral and non-significant character, tend
to have an altogether excessive, and even an absurd, influence on the
market. It is said, for example, that the shares of American companies
which manufacture ice tend to sell at a higher price in summer when
their profits are seasonally high than in winter when no one wants ice.
The recurrence of a bank-holiday may raise the market valuation of the
British railway system by several million pounds.
（２）現在の投資物件の利益の日々の変動は、明らかに一時的なものだったり無意味なものだったりしても、市場に対して過度の不合理な影響力をもつこと。例
えば、アメリカの製氷会社の株価は氷が売れない冬場よりも季節的な利益が多い夏場の方が高値で売れる傾向があると言われている。また、英国の鉄道の市場価
値は祝日がやってくるごとに起きる利用者増によってその都度上がるという。
(3) A conventional valuation which is established as the outcome of the
mass psychology（群集心理） of a large number of ignorant individuals is
liable to change violently as the result of a sudden fluctuation of
opinion due to factors which do not really make much difference to the
prospective yield; since there will be no strong roots of conviction to
hold it steady. In abnormal times in particular, when the hypothesis of
an indefinite continuance of the existing state of affairs is less
plausible than usual even though there are no express grounds to
anticipate a definite change, the market will be subject to waves of
optimistic and pessimistic sentiment, which are unreasoning and yet in
a sense legitimate where no solid basis exists for a reasonable
calculation.
（３） 慣習的評価（＝平均的人間による平均的評価）は大勢の無知な個人の群集心理の結果として定着しているものであるが、予想収益とあまりの関係のない
ことから世論が突然変化して、その結果、慣習的評価は急激に変化する傾向があること。というのは、慣習的評価を不変に保つ信念となる強力な根っこは全くな
いからである。特に混乱期には、明確な変化を予想する明らかな根拠が何もなくても、現状がいつまでも続くとする前提の信頼性が普通より低下しているので、
市場は楽観と悲観の波に翻弄されることになる。これは合理的なことではないが、合理的な計算の根拠が揺らいでいる場合にはある意味仕方のないことである。
(4) But there is one feature in particular which deserves our
attention. It might have been supposed that competition between expert
professionals, possessing judgment and knowledge beyond that of the
average private investor, would correct the vagaries of the ignorant
individual left to himself. It happens, however, that the energies and
skill of the professional investor and speculator are mainly occupied
otherwise. For most of these persons are, in fact, largely concerned,
not with making superior long-term forecasts of the probable yield of
an investment over its whole life, but with foreseeing changes in the
conventional basis of valuation（慣習的な評価の変化を予想する） a short time ahead of
the general public. They are concerned, not with what an investment is
really worth to a man who buys it “for keeps”, but with what the market
will value it at, under the influence of mass psychology, three months
or a year hence. Moreover, this behaviour is not the outcome of a
wrong-headed propensity. It is an inevitable result of an investment
market organised along the lines described. For it is not sensible to
pay 25 for an investment of which you believe the prospective yield to
justify a value of 30, if you also believe that the market will value
it at 20 three months hence.
（４）しかし特に注目に値する一つの特徴がある。プロの投資家たちは平均的な個人投資家よりも優れた知識と判断力をもっているので、彼らの競争によって無
知な個人投資家の気まぐれが正されると思わるかもしれない。しかし、実際にはプロの投資家と投機家たちのエネルギーはもっと別のことに費やされる。という
のは、これらの人たちの主な関心は、実際には投資の寿命期間の後の収益についての高度な長期予想ではなくて、一般大衆の短期間の後の慣習的な評価の変化を
予測することなのだ。彼らの関心は、どの投資物件が本気で購入する価値があるかではなく、三ヶ月か一年後に大衆心理の影響で市場はそれをどう評価するかな
のである。さらに、彼らのこの行動はひねくれた性格の結果ではない。それはすでに説明したように組織された投資市場の避けられない結果なのである。という
のは、三〇の価値の予測収益が見込める投資物件でも、三ヶ月後に市場が二〇に評価することが分かっているなら、その物件にいま二五を出すのは賢明なことで
はないからである。
Thus the professional investor is forced to concern himself with
the anticipation of impending changes, in the news（情勢） or in the
atmosphere, of the kind by which experience shows that the mass
psychology of the market is most influenced. This is the inevitable
result of investment markets organised with a view to so-called
“liquidity”. Of the maxims of orthodox finance none, surely, is more
anti-social than the fetish of liquidity, the doctrine that it is a
positive virtue on the part of investment institutions to concentrate
their resources upon the holding of “liquid” securities. It forgets
that there is no such thing as liquidity of investment for the
community as a whole. The social object of skilled investment should be
to defeat the dark forces of time and ignorance which envelop our
future. The actual, private object of the most skilled investment
to-day is “to beat the gun”, as the Americans so well express it, to
outwit the crowd, and to pass the bad, or depreciating, half-crown to
the other fellow.
つまり、プロの投資家は市場の大衆心理が最も大きく影響を受ける類（たぐい）の差し迫った情勢や雰囲気の変化を予測することに注意を向けざるをえないので
ある。これがいわゆる「流動性」を目指して組織された投資市場の避けがたい結果なのだ。正統派財政学の格言のうちでも「流動性の崇拝」ほど反社会的なもの
はない。それは投資機関は自分の能力を流動的券の保持に集中することが積極的な美徳であるとする教えである。社会全体にとっては投資物件が流動的であるこ
となどありえないことを、この格言は忘れている。熟練した投資家の社会的な使命は我々の将来を覆っている時間と無知の暗い力を打ち破ることでなければなら
ない。今日の最も熟練した投資家の実際の個人的な目的はアメリカ人がうまく表現したように「人を出し抜く」ことであり、群衆の裏をかくことであり、質の悪
い価値の下がった半クラウン硬貨を他人に回すことなのである。
This battle of wits to anticipate the basis of conventional
valuation（慣習的な評価を予測すること） a few months hence, rather than the
prospective yield of an investment over a long term of years, does not
even require gulls amongst the public to feed the maws of the
professional; ― it can be played by professionals amongst themselves.
Nor is it necessary that anyone should keep his simple faith in the
conventional basis of valuation having any genuine long-term validity.
For it is, so to speak, a game of Snap, of Old Maid, of Musical Chairs
― a pastime in which he is victor who says Snap neither too soon nor
too late, who passes the Old Maid to his neighbour before the game is
over, who secures a chair for himself when the music stops. These games
can be played with zest and enjoyment, though all the players know that
it is the Old Maid which is circulating, or that when the music stops
some of the players will find themselves unseated.
長い年月の後の投資の収益を予想するのではなく、今から二，三ヶ月後の慣習的評価を予想するこの知恵の争いにおいては、専門家の胃袋を満たす素人のカモは
必要としないのだ。このゲームは専門家たちだけで争われるのである。また、慣習的評価に本心から見た長期の有効性があると素朴に信じる人がいる必要はな
い。というのは、それは言わば、トランプのババ抜きや椅子取りゲームのようなものだからである。それはゲームが終わるまでにババを隣に回した人、音楽が止
まった時に椅子に座っていた人が勝つゲームである。ババが人の手を巡っていることはみんな知っているし、音楽が止まった時には誰かが椅子に座れないことを
みんな知っているにもかからず、こうしたゲームは夢中になって楽しめるのである。
Or, to change the metaphor slightly, professional investment may be
likened to those newspaper competitions in which the competitors have
to pick out the six prettiest faces from a hundred photographs, the
prize being awarded to the competitor whose choice most nearly
corresponds to the average preferences of the competitors as a whole;
so that each competitor has to pick, not those faces which he himself
finds prettiest, but those which he thinks likeliest to catch the fancy
of the other competitors, all of whom are looking at the problem from
the same point of view. It is not a case of choosing those which, to
the best of one's judgment, are really the prettiest, nor even those
which average opinion genuinely thinks the prettiest. We have reached
the third degree where we devote our intelligences to anticipating what
average opinion expects the average opinion to be. And there are some,
I believe, who practise the fourth, fifth and higher degrees.
あるいは比喩を変えるなら、プロの投資は参加者が６人の美人を１００枚の写真から選ぶ新聞紙上の美人コンテストに似ている。賞金は自分の選んだ女性が競技
の参加者全員の平均的な選択に最も近い人に与えられる。そのために、参加者は自分が最も美しいと思う女性を選ぶのではなく、他の参加者たちに最も好かれそ
うな女性を選ばなくてはならないので、全員が同じ観点から問題を見ることになる。それは自分の判断力の及ぶ限りで本当に最も美しい女性を選ぶのではなく、
平均的な意見が本心から誰を一番美しいと思っているかでもない。我々は平均的な意見は何を平均的な意見であると予想しているかを予想するために知性を注ぎ
込むという第三のレベルにたどり着いたのである。そして恐らく中には第四、第五いやもっと高度なレベルを実践している人もいるだろう。
If the reader interjects that there must surely be large profits
to be gained from the other players in the long run by a skilled
individual who, unperturbed by the prevailing pastime, continues to
purchase investments on the best genuine long-term expectations he can
frame, he must be answered, first of all, that there are, indeed, such
serious-minded individuals and that it makes a vast difference to an
investment market whether or not they predominate in their influence
over the game-players. But we must also add that there are several
factors which jeopardise the predominance of such individuals in modern
investment markets. Investment based on genuine long-term expectation
is so difficult to-day as to be scarcely practicable. He who attempts
it must surely lead much more laborious days and run greater risks than
he who tries to guess better than the crowd how the crowd will behave;
and, given equal intelligence, he may make more disastrous mistakes.
読者から次のような反論が出るかもしれない。世の中の投資ゲームに惑わされずに、自分が本心から立てた長期の最善の予想にもとづいて投資物件を購入し続け
る熟練した投資家が結局は投資ゲームに興ずる人たちよりも多くの利益を手にするはずだと。それに対する答えは、まず第一に次のようになるに違いない。その
ような真面目な投資家は確かに存在するし、彼らがゲーム感覚の投資家たちに対して優位を占めるかどうかで投資市場に大きな違いをもたらすはずだと。しか
し、ここで付け加えなければならないのは、そのような個人の投資家が現代の投資市場で優位を占めることを危うくするような要因が沢山存在することである。
本心から立てた長期予想に基づく投資は今日では非常に難しいので殆ど実行不可能となっているのである。それを実行しようとする人は、群衆がどう振る舞うか
を群集よりも上手く推測しようとする人よりも遥かに多くの苦労しながら遥かに大きなリスクを冒さなければならない。そして、同じ知性があるとしても、遥か
に悲惨な失敗をする可能性がある。
There is no clear evidence from experience that the investment policy
which is socially advantageous coincides with that which is most
profitable. It needs more intelligence to defeat the forces of time and
our ignorance of the future than to beat the gun. Moreover, life is not
long enough; ― human nature desires quick results, there is a peculiar
zest in making money quickly, and remoter gains are discounted by the
average man at a very high rate. The game of professional investment is
intolerably boring and over-exacting to anyone who is entirely exempt
from the gambling instinct; whilst he who has it must pay to this
propensity the appropriate toll. Furthermore, an investor who proposes
to ignore near-term market fluctuations needs greater resources for
safety and must not operate on so large a scale, if at all, with
borrowed money ― a further reason for the higher return from the
pastime to a given stock of intelligence and resources. Finally it is
the long-term investor, he who most promotes the public interest, who
will in practice come in for most criticism, wherever investment funds
are managed by committees or boards or banks.[4] For it is in the
essence of his behaviour that he should be eccentric, unconventional
and rash in the eyes of average opinion. If he is successful, that will
only confirm the general belief in his rashness; and if in the short
run he is unsuccessful, which is very likely, he will not receive much
mercy. Worldly wisdom teaches that it is better for reputation to fail
conventionally than to succeed unconventionally.
経験から言って、社会に役立つ投資政策が最も利益の上がるものであるという明確な証拠はない。時間の力と未来に対する無知の力を打ち破るには、仲間を出し
抜くよりも多くの知性を必要とする。さらに、人生は充分に長くはない。人間の本姓は素早い結果を要求する。お金を急いでを作りたいという異常な熱意があ
る。遠い先の利益は平均的な人間にとっては高い割合で割引かれた価値しかない。プロの投資ゲームはギャンブルの才能がない人にはまったく退屈で耐え難いも
のであるが、ギャンブルの才能がある人はその性向のために相応の代価を支払う必要がある。そのうえ、投資家が市場の短期の変動を無視しようとするなら、安
全のためにもっと多くの資産が必要になるし、やるとしても借入金でそれほど大きな売買をすべきではない。これもまた、知性と資金が同じなら投資ゲームの方
が利益が大きいと言える理由である。最後に、投資資金が委員会や評議会や銀行で管理される場合は、最も社会のためになるはずの長期の投資家が最も批判を受
けることになる[４]。というのは、平均的な人から見て、投資家の行動の本質は、風変わりで型にはまらず向こう見ずであるとされるからである。投資家は仮
にもし成功しても、世間は投資家の向こう見ずを確認するだけであり、そして、もし短期間に損をしても（こちらの方が確率は高い）、あまり同情してはもらえ
ない。世知の教えるところでは、突飛なことをして成功するより慣習に従って失敗するほうが評判はよいものだ。
(5) So far we have had chiefly in mind the state of confidence of the
speculator or speculative investor himself and may have seemed to be
tacitly assuming that, if he himself is satisfied with the prospects,
he has unlimited command over money at the market rate of interest.
This is, of course, not the case. Thus we must also take account of the
other facet of the state of confidence, namely, the confidence of the
lending institutions towards those who seek to borrow from them,
sometimes described as the state of credit. A collapse in the price of
equities, which has had disastrous reactions on the marginal efficiency
of capital, may have been due to the weakening either of speculative
confidence or of the state of credit. But whereas the weakening of
either is enough to cause a collapse, recovery requires the revival of
both. For whilst the weakening of credit is sufficient to bring about a
collapse, its strengthening, though a necessary condition of recovery,
is not a sufficient condition.
（５）これまで我々は投機家や投機的な投資家の確信度だけを考慮に入れて、投機家が自分の予想に自信があるなら市場の利子率でお金を無制限に調達できると
暗黙のうちに考えてきた。しかし、もちろん、事実はそうではない。つまり、我々は確信度の別の面、貸し手の機関が借り手に対して抱く確信、時に信用度と言
われるものも考慮に入れる必要がある。資本の限界効率に破壊的な作用をしてきた株価の暴落の原因は、この確信の度合いか信用の度合いのいずれかの低下だと
言えるのである。しかし、暴落を引き起こすのはどちらか一方の低下で充分だが、回復には両方の復活が必要である。信用の低下は暴落を引き起こすのに充分だ
が、信用の復活は回復の必要条件ではあっても充分条件ではないからである。
VI
These considerations should not lie beyond the purview of the
economist. But they must be relegated to their right perspective. If I
may be allowed to appropriate the term speculation for the activity of
forecasting the psychology of the market, and the term enterprise for
the activity of forecasting the prospective yield of assets over their
whole life, it is by no means always the case that speculation
predominates over enterprise. As the organisation of investment markets
improves, the risk of the predominance of speculation does, however,
increase. In one of the greatest investment markets in the world,
namely, New York, the influence of speculation (in the above sense) is
enormous. Even outside the field of finance, Americans are apt to be
unduly interested in discovering what average opinion believes average
opinion to be; and this national weakness finds its nemesis in the
stock market. It is rare, one is told, for an American to invest, as
many Englishmen still do, “for income”; and he will not readily
purchase an investment except in the hope of capital appreciation. This
is only another way of saying that, when he purchases an investment,
the American is attaching his hopes, not so much to its prospective
yield, as to a favourable change in the conventional basis of
valuation, i.e. that he is, in the above sense, a speculator.
経済学者はこうした検討材料を視野に入れておく必要があるが、その場合にも正しい観点から観察しなければならない。もし投機という言葉を市場心理を予測
する行動に充てて、企業活動という言葉を資産の寿命後の収益を予測する行動に充てることが許されるなら、投機は企業活動に対して優位に立つというのは決し
ていつも真実ではない。しかしながら、投資市場の組織化が進んで、投機が優位を占める危険性が高くなっている。世界で最大の投資市場であるニューヨークで
は、上記の意味における投機の影響力は絶大である。金融以外の分野でも、アメリカ人は「平均的な意見が平均的な意見を何であると思っているか」について異
常なほどに関心がある。そして、この国民的な弱点が株式市場で罰を受けているのである。今でも多くのイギリス人は「所得のために」投資をするが、同じよう
に投資をするアメリカ人は珍しいと言われている。アメリカ人が進んで投資物件を購入するのは資本の騰貴が望めるときだけである。これは、アメリカ人が投資
物件を購入するとき期待するのはその予想収益ではなく慣習的な評価の好都合な変化であるということの単なる言い換えであり、アメリカ人は上記の意味での投
機家であるということの言い換えである。
Speculators may do no harm as bubbles on a steady stream of enterprise.
But the position is serious when enterprise becomes the bubble on a
whirlpool of speculation. When the capital development of a country
becomes a by-product of the activities of a casino, the job is likely
to be ill-done. The measure of success attained by Wall Street,
regarded as an institution of which the proper social purpose is to
direct new investment into the most profitable channels in terms of
future yield, cannot be claimed as one of the outstanding triumphs of
laissez-faire capitalism ― which is not surprising, if I am right in
thinking that the best brains of Wall Street have been in fact directed
towards a different object.
投機家が企業活動の安定した流れに浮かぶ泡沫であるなら何の害もないかもしれない。ところが、企業活動の方が投機の渦の中に浮かぶ泡沫になるなら事態は深
刻である。一国の資本の発展がカジノの副産物になるとき、その仕事はおそらく失敗する。ウォール・ストリートを将来の収益から見て最も有利な分野に新たな
投資を呼び込むことを本来の社会的目的とする機関であると見るならば、それが達成した成功は自由放任の資本主義の際立った勝利の一つであると主張すること
は出来ない。ウォール・ストリートの最高の知能は実際には別の目的に向けられていると考えるのが間違いでないのなら、それは驚くべきことではない。
These tendencies are a scarcely avoidable outcome of our having
successfully organised “liquid” investment markets. It is usually
agreed that casinos should, in the public interest, be inaccessible and
expensive. And perhaps the same is true of Stock Exchanges. That the
sins of the London Stock Exchange are less than those of Wall Street
may be due, not so much to differences in national character, as to the
fact that to the average Englishman Throgmorton Street is, compared
with Wall Street to the average American, inaccessible and very
expensive. The jobber's “turn”, the high brokerage charges and the
heavy transfer tax payable to the Exchequer, which attend dealings on
the London Stock Exchange, sufficiently diminish the liquidity of the
market (although the practice of fortnightly accounts operates the
other way) to rule out a large proportion of the transactions
characteristic of Wall Street.[5] The introduction of a substantial
Government transfer tax on all transactions might prove the most
serviceable reform available, with a view to mitigating the
predominance of speculation over enterprise in the United States.
我々が「流動的」な投資市場を作り上げた以上は、こうした傾向はもはや避けられない。人々が普通一致した意見では、公衆の利益のためにはカジノは近づきに
くく高くつく所にしなければならない。そしておそらく株式市場についても同じことが言える。ロンドンの株式市場がウォール・ストリートほど罪深くないの
は、国民性の違いのせいではなく、平均的なイギリス人にとってスロッグモートン街は、平均的なアメリカ人にとってのウォール・ストリートよりも、近づきに
くく高くつく所であるためである。ロンドンの株式市場では取引に必要な株式仲買人の手数料もブローカーの手数料も大蔵省へ払う譲渡税も高く、そのために市
場の流動性が弱められているので（ただし隔週決済の習慣は逆の方向に働いているが）、ウォール・ストリート[５]に特有の取引の多くが出来なくなってい
る。アメリカ合衆国で投機が企業活動に対して優位に立っている現状を改善したければ、政府があらゆる取引にもっと大規模な譲渡税を導入すれば、最も効果的
な改革になるかもしれない。
The spectacle of modern investment markets has sometimes moved me
towards the conclusion that to make the purchase of an investment
permanent and indissoluble, like marriage, except by reason of death or
other grave cause, might be a useful remedy for our contemporary evils.
For this would force the investor to direct his mind to the long-term
prospects and to those only. But a little consideration of this
expedient brings us up against a dilemma, and shows us how the
liquidity of investment markets often facilitates, though it sometimes
impedes, the course of new investment. For the fact that each
individual investor flatters himself that his commitment is “liquid”
(though this cannot be true for all investors collectively) calms his
nerves and makes him much more willing to run a risk. If individual
purchases of investments were rendered illiquid, this might seriously
impede new investment, so long as alternative ways in which to hold his
savings are available to the individual. This is the dilemma. So long
as it is open to the individual to employ his wealth in hoarding or
lending money, the alternative of purchasing actual capital assets
cannot be rendered sufficiently attractive (especially to the man who
does not manage the capital assets and knows very little about them),
except by organising markets wherein these assets can be easily
realised for money.
近代の投資市場の有様を見ると、私は投資物件の購入を婚姻関係のように永久化して死亡など深刻な理由なしには解消できないようにするのが、現在の諸悪に対
する有効な治療策になるかもしれないと言いたくなる。というのは、こうすれば投資家は長期予想だけに目を向けざるを得なくなるからである。しかし、この方
法は少し考えるとすぐにジレンマに突き当たる。投資市場の流動性によって、新しい投資の進行が妨げられることが時にはあっても、多くの場合新たな投資の進
行がそれによって容易になっていることを、我々は認めざるをえないからである。というのは、個人の投資家は自分の投資物件が流動的であると思えると、安心
してもっと多くのリスクを冒す気になるからである。もし個人の投資物件の購入が流動的でなくなったら、貯蓄を保有する別の選択肢が利用可能な場合には、新
たな投資はひどく妨げられる可能性がある。これはジレンマである。自分の金を貯めこんでおくか貸し出すかを個人が選べる場合に、その金で現物の資本設備を
購入するという選択肢を魅力的にするには（特に投資家が資本設備を管理せずそれについても殆ど知識がない場合）、この資産を簡単に現金化できるような市場
を組織する以外にはないのである。
The only radical cure for the crises of confidence（確信度の危機＝景気見通しの危機）
which afflict the economic life of the modern world would be to allow
the individual no choice between consuming his income and ordering the
production of the specific capital-asset which, even though it be on
precarious evidence, impresses him as the most promising investment
available to him. It might be that, at times when he was more than
usually assailed by doubts concerning the future, he would turn in his
perplexity towards more consumption and less new investment. But that
would avoid the disastrous, cumulative and far-reaching repercussions
of its being open to him, when thus assailed by doubts, to spend his
income neither on the one nor on the other.
近代社会の経済活動を悩ましている確信度の危機を根本から解決する唯一の方法は、個人が自分の所得を消費するか、不確かな証拠に基づいていても自分に最も
有望な投資だと思われる特定の資本資産の製造を注文する以外の選択肢をなくすことである。将来の不安に苛まれている時には、戸惑いの中で消費増やすして新
たな投資を減らすことだろう。しかし、不安に駆られて自分の所得をそのどちらにも使わないことが許される時に生ずる破壊的累積的で広範囲の影響をそれで回
避することができるのである。
Those who have emphasised the social dangers of the hoarding of money
have, of course, had something similar to the above in mind. But they
have overlooked the possibility that the phenomenon can occur without
any change, or at least any commensurate change, in the hoarding of
money.
金を消費にも投資にもまわさず家に貯めこむことの社会的な危険を強調する人たちは、もちろん、これと似たような事を考えていたのである。しかし、彼らはこ
うした危険な現象が発生しても、貯めこんだ現金の量には何の変化も起きない、少なくともその現金量に比例した変化は起きないという可能性は見逃した。
VII
Even apart from the instability due to speculation, there is the
instability due to the characteristic of human nature that a large
proportion of our positive activities depend on spontaneous optimism
rather than on a mathematical expectation, whether moral or hedonistic
or economic. Most, probably, of our decisions to do something positive,
the full consequences of which will be drawn out over many days to
come, can only be taken as a result of animal spirits ― of a
spontaneous urge to action rather than inaction, and not as the outcome
of a weighted average of quantitative benefits multiplied by
quantitative probabilities. Enterprise only pretends to itself to be
mainly actuated by the statements in its own prospectus, however candid
and sincere. Only a little more than an expedition to the South Pole,
is it based on an exact calculation of benefits to come. Thus if the
animal spirits are dimmed and the spontaneous optimism falters, leaving
us to depend on nothing but a mathematical expectation, enterprise will
fade and die; ― though fears of loss may have a basis no more
reasonable than hopes of profit had before.
投機に起因する不安定さのほかに、人間の本姓の特徴に起因する不安定さがある。その特徴は、我々の積極的な行動のほとんどは数学的な予想に基づくものでは
なく、道徳的あるいは快楽主義的あるいは経済的な、前向きの楽観主義に依存しているということである。おそらく我々が何か積極的なことをする決断の多く
は、結果が出るまで長い年月がかかるような事であっても、それはアニマル・スピリット（血気）の結果であり、何もしないよりは何かしようとする前向きな衝
動の結果であって、加重平均した量的利益に量的確率をかけた結果ではないと考えてよい。企業の設立趣意書の中身がどれほど率直で本当らしくても、企業はそ
れを主な動機にしているという振りをしているだけである。企業が将来の利益の正確な計算の上に立っているとしても、それは南極探検と同程度か、それより少
しましな程度でしかない。つまり、もしアニマル・スピリットが薄れて、前向きの楽観主義が揺らぐようなことになって、頼りになるのは数字上の予想だけに
なったら、その企業は衰弱して死に絶える運命にある。もっとも、その段階での損失の恐怖に合理的理由はないのは、最初の利益の希望にも合理的な理由はない
のと同じである。
It is safe to say that enterprise which depends on hopes
stretching into the future benefits the community as a whole. But
individual initiative will only be adequate when reasonable calculation
is supplemented and supported by animal spirits, so that the thought of
ultimate loss which often overtakes pioneers, as experience undoubtedly
tells us and them, is put aside as a healthy man puts aside the
expectation of death.
未来に広がる希望（＝長期の予想収益）に依存する企業は社会全体の為になることをしていると言って間違いはない。しかし、個々の創業心は、合理的な計算が
アニマルスピリット（血気）によって補完され支えれたとき初めて十全なものとなるのである。その時、経験が疑いもなく教えるように、健康な人間がいつかは
死ぬ事を忘れてしまうように、最終的に損をするかもしれないという思い（＝長期予想）は創業者の頭から吹き飛んでしまうのである。
This means, unfortunately, not only that slumps and depressions are
exaggerated in degree, but that economic prosperity is excessively
dependent on a political and social atmosphere which is congenial to
the average business man. If the fear of a Labour Government or a New
Deal depresses enterprise, this need not be the result either of a
reasonable calculation or of a plot with political intent; ― it is the
mere consequence of upsetting the delicate balance of spontaneous
optimism. In estimating the prospects of investment, we must have
regard, therefore, to the nerves and hysteria and even the digestions
and reactions to the weather of those upon whose spontaneous activity
it largely depends.
このことが意味するのは、不幸なことに、不景気と不況は実際よりも過度に強調されるということだけでなく、経済的な繁栄が平均的な実業家のもっている政治
的社会的な気分に過度に依存しているということでもある。もし労働党政権かニューディール政策への恐怖が企業を抑圧するなら、それは必ずしも合理的な計算
の結果でも、政治的意図をもった計画の結果であるとも言えない。むしろ、それは単なる前向きの楽観主義の微妙なバランスが壊された結果でしかないのだ。し
たがって、投資の将来を予測するにあたっては、それが投資家の前向きの行動力に依存している以上は、我々は彼らの神経とヒステリーと消化の良さと天気への
反応にも留意しなければならないのである。
We should not conclude from this that everything depends on waves of
irrational psychology. On the contrary, the state of long-term
expectation is often steady, and, even when it is not, the other
factors exert their compensating effects. We are merely reminding
ourselves that human decisions affecting the future, whether personal
or political or economic, cannot depend on strict mathematical
expectation, since the basis for making such calculations does not
exist; and that it is our innate urge to activity which makes the
wheels go round, our rational selves choosing between the alternatives
as best we are able, calculating where we can, but often falling back
for our motive on whim or sentiment or chance.
ここからすべてが不合理な心理の波に依存していると我々は結論すべきではない。その反対に、長期予想はしばしば安定的であり、そうでない時でも、それを補
う効果を持つ要素は他にも沢山ある。我々は単に次のことを忘れないようにしているだけである。つまり、未来に影響を与える人間の決定は、個人的政治的経済
的を問わず、厳密な数学的予想に依拠しているわけではない。なぜなら、そのような計算をするための根拠は存在しないからである。また、世の中を動かしてい
るのは行動への内的な衝動であって、我々の理性的な自己は可能な時には計算するが、多くの場合は気まぐれな感情と運委せの動機から、選択肢のうちで出来る
だけ最良のものを選んでいるにすぎない。
VIII
There are, moreover, certain important factors which somewhat
mitigate in practice the effects of our ignorance of the future. Owing
to the operation of compound interest（複利） combined with the likelihood
of obsolescence with the passage of time, there are many individual
investments of which the prospective yield is legitimately dominated by
the returns of the comparatively near future. In the case of the most
important class of very long-term investments, namely buildings, the
risk can be frequently transferred from the investor to the occupier,
or at least shared between them, by means of long-term contracts, the
risk being outweighed in the mind of the occupier by the advantages of
continuity and security of tenure. In the case of another important
class of long-term investments, namely public utilities（公共事業）, a
substantial proportion of the prospective yield is practically
guaranteed by monopoly privileges coupled with the right to charge such
rates（料金） as will provide a certain stipulated margin（利潤）.
さらに、我々の未来に対する無知の悪影響を実際上いくらか緩和してくれる重要な要素がいくつか存在する。複利計算と時間の経過で投資資産（＝機械）が旧式
化する可能性のために、個々の投資物件の中には、当然のことながら比較的近い将来の利潤によって予想収益が決まってくるものが沢山ある。最も重要な長期投
資の分野であるビルディングの場合には、保有期間（＝借家権）の継続性と安全性の利益の方がテナントの心理ではリスクより上回るので、長期の契約によって
リスクはしばしば投資家からテナントに移転されことがあるし、少なくとも両者で分け合うことが可能である。もう一つ重要な長期投資の分野である公共事業の
場合には、規定の利潤を稼ぐ料金設定権など様々な独占的権利によって予想収益の非常に大きな部分が事実上保証されている。
Finally there is a growing class of investments entered upon by, or at
the risk of, public authorities（公共機関）, which are frankly influenced in
making the investment by a general presumption of there being
prospective social advantages from the investment, whatever its
commercial yield may prove to be within a wide range, and without
seeking to be satisfied that the mathematical expectation of the yield
is at least equal to the current rate of interest, ― though the rate
which the public authority has to pay may still play a decisive part in
determining the scale of investment operations which it can afford.
最後に今増大しつつある投資分野が一つある。それは公共機関が自分のリスクで始めた投資である。この投資は将来の社会の為になるとする一般的な考え方が大
きな力をもっているので、その商業的利益はある広い範囲の中に収まっていればかまわないし、収益の数的な予想が少なくとも現行利子率に一致すべきだとする
条件を満たす必要もない。ただし、公共機関が行う投資活動の規模を決めるときには、それが支払う利子率は重要な役割を持つことはある。
Thus after giving full weight to the importance of the influence of
short-period changes in the state of long-term expectation as distinct
from changes in the rate of interest, we are still entitled to return
to the latter as exercising, at any rate, in normal circumstances, a
great, though not a decisive, influence on the rate of investment. Only
experience, however, can show how far management of the rate of
interest is capable of continuously stimulating the appropriate volume
of investment.
以上において利子率の変化とは別に長期予想の短期の変化が投資に対してもたらす影響の大きさは充分に説明したので、今や我々はやはり利子率が、少なくとも
普通の状況では、投資量に対して決定的ではなくても重要な役割を果たすという話に戻ってもよいだろう。しかしながら、利子率を管理することによって適当な
投資量を継続的に刺激することがどこまで出来るのかは経験からしかわからない。
For my own part I am now somewhat sceptical of the success of a merely
monetary policy（通貨政策、金融施策） directed towards influencing the rate of
interest. I expect to see the State, which is in a position to
calculate the marginal efficiency of capital-goods on long views and on
the basis of the general social advantage, taking an ever greater
responsibility for directly organising investment; since it seems
likely that the fluctuations in the market estimation of the marginal
efficiency of different types of capital, calculated on the principles
I have described above, will be too great to be offset by any
practicable changes in the rate of interest.
私の考えでは、利子率に影響を与える目的で行われる単なる通貨政策がうまくいくかどうかは疑わしいと思っている。長期的な視点で一般的な社会福祉のために
資本財の限界効率を計算できる国家が、大きな責任をもって投資の組織に直接乗り出すようになることを、私は期待している。というのは、様々なタイプの資本
の限界効率は市場の評価（私が上記で示した原理に従って計算された）の変動があまりに大きく、利子率の実際的な変化によって緩和できないからである。
Author's Footnotes
[1]. By “very uncertain' I do not mean the same thing as “improbable”.
Cf. my Treatise on Probability, chap. 6, on “The Weight of Arguments”.
[2]. In my Treatise on Money (vol. ii. p. 195) I pointed out that when
a company's shares are quoted very high so that it can raise more
capital by issuing more shares on favourable terms, this has the same
effect as if it could borrow at a low rate of interest. I should now
describe this by saying that a high quotation for existing equities
involves an increase in the marginal efficiency of the corresponding
type of capital and therefore has the same effect (since investment
depends on a comparison between the marginal efficiency of capital and
the rate of interest) as a fall in the rate of interest.
[3]. This does not apply, of course, to classes of enterprise which are
not readily marketable or to which no negotiable instrument（換金できる証券）
closely corresponds. The categories falling within this exception were
formerly extensive. But measured as a proportion of the total value of
new investment they are rapidly declining in importance.
[4]. The practice, usually considered prudent, by which an investment
trust or an insurance office frequently calculates not only the income
from its investment portfolio but also its capital valuation in the
market, may also tend to direct too much attention to short-term
fluctuations in the latter.
[5]. It is said that, when Wall Street is active, at least a half of
the purchases or sales of investments are entered upon with an
intention on the part of the speculator to reverse them the same day.
This is often true of the commodity exchanges also.
著者注
[１] 「非常に不確か」という言葉で私が意味するのは「ありそうにない」という言葉と同じではない。私の『確率論』第６章「推論の重みについて」参照。
[２] 自著『貨幣論』（第二巻１９５頁）で私は次の指摘をした。ある企業の株式に高値がついて好条件でさらに多くの株式を発行することでより多くの資本
を調達できるとき、このことは低利子率で借入れ出来るのと同じ事だと。今なら次のように言う。既存株式に高値が付くことはその株式に対応する資本の限界効
率が上がっていることを意味し、（投資は資本の限界効率と利子率を比較して行われるから）利子率の低下と同じ効果があると。
[３] 容易に市場化できない企業や流通証券がない企業にはこれは当てはまらない。この例外に属する部門は昔はかなり多かった。しかし、新投資の全価値のある部分として測ったとき、それらの重要性は急速に低下している。
[４] 投資信託や保険会社がしばしば投資のポートフォリオ（＝複数の株式にリスクを分散して資産運用すること）からの所得だけでなく資本の市場価値も計算する際の賢明なやり方によれば、彼らは後者の短期の変動にあまりにも注目し過ぎる傾向がある。
[５] ウォール・ストリートが活況の時には、投資物件の売買の少なくとも半分は投機家がその日の内に反対売買する積りで行われると言われている。商品取引についてもしばしば同じ事が言える。
Chapter 13. The General Theory of the Rate of Interest
第１３章 利子率の一般理論
I
WE have shown in Chapter 11 that, whilst there are
forces（＝上ではfactors） causing the rate of investment to rise or fall so
as to keep the marginal efficiency of capital equal to the rate of
interest, yet the marginal efficiency of capital is, in itself, a
different thing from the ruling rate of interest. The schedule of the
marginal efficiency of capital may be said to govern the terms on which
loanable funds are demanded for the purpose of new investment; whilst
the rate of interest governs the terms on which funds are being
currently supplied. To complete our theory, therefore, we need to know
what determines the rate of interest.
第１節
１１章において我々は資本の限界効率が利子率と等しくなるように投資量を上下させる要素が存在するが（＝内部収益率法）、資本の限界効率それ自体は支配的
な利子率（＝市場利子率）とは別物であることを明らかにした（＝第５節）。資本の限界効率表は、新たな投資のために借り入れる資金需要が起きる条件を決め
るものであり、それに対して、利子率は現在における資金供給の条件を決めるものであると言っていい。したがって、我々の理論を完成するためには、利子率を
決めるものが何であるかを知る必要がある。
In Chapter 14 and its Appendix we shall consider the answers to
this question which have been given hitherto. Broadly speaking, we
shall find that they make the rate of interest to depend on the
interaction of the schedule of the marginal efficiency of capital with
the psychological propensity to save. But the notion that the rate of
interest is the balancing factor which brings the demand for saving in
the shape of new investment forthcoming at a given rate of interest
into equality with the supply of saving which results at that rate of
interest from the community's psychological propensity to save, breaks
down as soon as we perceive that it is impossible to deduce the rate of
interest merely from a knowledge of these two factors.
What, then, is our own answer to this question?
第１４章とその付録で我々はこの問題に対して現在まで提示されている答えを検討する。大雑把に言って、利子率は資本の限界効率表と心理的な貯蓄性向の相互
作用によって決まるとされていることを我々は見出すだろう。しかしながら、利子率は貯蓄需要と貯蓄供給を一致される均衡要因であるとする考え方、つまり、
ある利子率で新投資として出てくる貯蓄需要と、その利子率で社会の心理的貯蓄性向から出てくる貯蓄供給を一致させる均衡要因であるとする考え方は、この二
つの要素（＝投資と貯蓄）が分かっても利子率を導き出せないことが分かるやいなや崩壊するのである。
では、この問題に対する我々の答えは何だろうか？
II
The psychological time-preferences of an individual require two
distinct sets of decisions to carry them out completely. The first is
concerned with that aspect of time-preference which I have called the
propensity to consume, which, operating under the influence of the
various motives set forth in Book III, determines for each individual
how much of his income he will consume and how much he will reserve in
some form of command over future consumption.
個人の心理的な時間選好（＝将来の消費よりも現在の消費を優先する傾向）を実行するには二つの異なる決定をする必要がある。その一つは時間選好のうちで消
費性向と私が呼ぶものに関する決定である。消費性向とは、第３巻に示した様々な動機から、個々の人間が自分の所得の内のいくらを消費して、いくらを将来の
消費に対する権利として何らかの形で保有するかを決めるものである。
But this decision having been made, there is a further decision
which awaits him, namely, in what form he will hold the command over
future consumption which he has reserved, whether out of his current
income or from previous savings. Does he want to hold it in the form of
immediate, liquid command (i.e. in money or its equivalent)? Or is he
prepared to part with immediate command for a specified or indefinite
period, leaving it to future market conditions to determine on what
terms he can, if necessary, convert deferred command over specific
goods into immediate command over goods in general? In other words,
what is the degree of his liquidity-preference ― where an individual's
liquidity-preference is given by a schedule of the amounts of his
resources, valued in terms of money or of wage-units, which he will
wish to retain in the form of money in different sets of circumstances?
しかし、この決定をしてからさらにもう一つしなければならない決定がある。それは当期の所得にしろ以前の貯蓄にしろ、その内から将来の消費に対する権利
をどのような形で保有するかという問題である。その権利を直接的な流動性のある形（貨幣かそれに相当するもの）で保つか、それとも、特定の期間だけあるい
は期間を設けずにその直接的権利を手放す（＝債権の購入）ことにするかという問題である。後者の場合には、特定の財に対する猶予された権利を、普遍的な財
に対する直接的権利に変換する条件の決定を、将来の市場の状況に委ねることになる。別の言葉で言えば、彼の流動性選好はどの程度であるかという問題であ
る。― 個人の流動性選好は、様々な状況で資産（貨幣あるいは単位賃金数で測った）を貨幣での保有を希望する量のグラフによって表される。
We shall find that the mistake in the accepted theories of the
rate of interest lies in their attempting to derive the rate of
interest from the first of these two constituents of psychological
time-preference to the neglect of the second; and it is this neglect
which we must endeavour to repair.
現行の利子率理論の間違いは、利子率が時間選好のこの二つの心理的要因のうちの最初のものだけから説明されていて、二番目のものを無視していることである。
It should be obvious that the rate of interest cannot be a
return to saving or waiting（待忍） as such. For if a man hoards his
savings in cash, he earns no interest, though he saves just as much as
before. On the contrary, the mere definition of the rate of interest
tells us in so many words that the rate of interest is the reward for
parting with liquidity for a specified period. For the rate of interest
is, in itself, nothing more than the inverse proportion between a sum
of money and what can be obtained for parting with control over the
money in exchange for a debt[1] for a stated period of time.[2]
利子率が単に貯蓄や待忍（＝消費を控えること）の報酬でないのは明らかである。というのは、貯蓄の量は同じでも現金で保有したら利子は稼げないからであ
る。逆に、利子率の定義を見ればわかるが、そこで万言を費やして言われていることは、利子率とは流動性を一定期間手放すことに対する報酬なのである。それ
はある金額と、その金額を債券[１]と交換に一定期間手放すことで得られる金額（＝利子）の逆比率にほかならない[２]。
Thus the rate of interest at any time, being the reward for
parting with liquidity, is a measure of the unwillingness of those who
possess money to part with their liquid control over it. The rate of
interest is not the “price” which brings into equilibrium the demand
for resources to invest with the readiness to abstain from present
consumption. It is the “price” which equilibrates the desire to hold
wealth in the form of cash with the available quantity of cash; ― which
implies that if the rate of interest were lower, i.e. if the reward for
parting with cash were diminished, the aggregate amount of cash which
the public would wish to hold would exceed the available supply, and
that if the rate of interest were raised, there would be a surplus of
cash which no one would be willing to hold. If this explanation is
correct, the quantity of money is the other factor, which, in
conjunction with liquidity-preference, determines the actual rate of
interest in given circumstances. Liquidity-preference is a potentiality
or functional tendency, which fixes the quantity of money which the
public will hold when the rate of interest is given; so that if r is
the rate of interest, M the quantity of money and L the function of
liquidity-preference, we have M = L(r). This is where, and how, the
quantity of money enters into the economic scheme.
つまり、いつの時点でも利子率とは、流動性を手放すことの報酬であるから、貨幣の所持者が貨幣に対する流動的支配を放棄することをどれほど嫌がっている
かということを示す尺度である。利子率とは投資資金に対する需要（＝資金需要、投資）と今の消費を控えたいという気持ち（＝資金供給、貯蓄）を均衡させる
「価格」ではない。富を現金で保有したいという気持ち（＝貨幣需要）と、社会に出回っている現金量（＝貨幣供給）を均衡させる「価格」である。―
これはどういうことかというと、もし利子率が下がって現金を手放すことに対する報酬が下がったら、みんなが現金を手元に置きたがって、その合計（＝貨幣需
要）は社会で利用可能な貨幣供給を超えてしまうだろう。またもし利子率が上がれば、誰も現金を保持しようとしなくなって、現金があり余ってしまうだろう
（＝どちらも均衡が崩れる）。もしこの説明が正しければ、所与の環境において流動性選好と結びついて現行の利子率を決めるもう一つの要素として貨幣量があ
ることになる。流動性選好とは潜在的な傾向、あるいは関数的な傾向であり、利子率が与えられた時に社会が保有しようとする貨幣量（＝貨幣需要）を決めるも
のである。そこで、もしｒを利子率とし、Ｍを貨幣量とし、Ｌを流動性選好の関数とすると、Ｍ＝Ｌ（ｒ）（＝あとでＬ２として再登場する、貨幣需要関数）。
こうして経済の仕組みの中に貨幣量が入ってくるのである。
At this point, however, let us turn back and consider why such a
thing as liquidity-preference exists. In this connection we can
usefully employ the ancient distinction between the use of money for
the transaction of current business and its use as a store of wealth.
As regards the first of these two uses, it is obvious that up to a
point it is worth while to sacrifice a certain amount of interest for
the convenience of liquidity. But, given that the rate of interest is
never negative, why should anyone prefer to hold his wealth in a form
which yields little or no interest to holding it in a form which yields
interest (assuming, of course, at this stage, that the risk of default
is the same in respect of a bank balance as of a bond)? A full
explanation is complex and must wait for Chapter 15. There is, however,
a necessary condition failing which the existence of a
liquidity-preference for money as a means of holding wealth could not
exist.
しかし、ここで振り返って流動性選好なるものがどうして存在するか考えてみよう。この関連においては、貨幣の用途として、当面の商取引のための用途と富
の蓄積のために用途という昔ながらの区別を使うのが便利である。この二つの用途のうちの最初のものについては、流動性という便宜を獲得するために多少の利
益を犠牲にする価値があるのは明らかである。しかし、利子率は決してマイナスになることはないのに、どうして利益をもたらす形でなく、利益をほとんどある
いは全くもたらさない形で自分の富を保有しようとする人がいるのだろうか（もちろんこの段階では破産リスクは銀行預金も公債も同じだとする）。この完全な
説明は複雑で第１５章を待たねばならない。しかしながら、富を保有する手段として貨幣の流動性選好が存在するためには、欠くことの出来ない必要条件が一つ
ある。
This necessary condition is the existence of uncertainty as to
the future of the rate of interest, i.e. as to the complex of rates of
interest（利子率複合体） for varying maturities which will rule at future
dates. For if the rates of interest ruling at all future times could be
foreseen with certainty, all future rates of interest could be inferred
from the present rates of interest for debts（債権） of different
maturities, which would be adjusted to the knowledge of the future
rates. For example, if 1Dr is the value in the present year 1 of ￡1
deferred r years and it is known that nDr will be the value in the year
n of ￡1 deferred r years from that date, we have
nDr = 1Dn+r / 1Dn ;
whence it follows that the rate at which any debt can be turned into
cash n years hence is given by two out of the complex of current rates
of interest. If the current rate of interest is positive for debts of
every maturity, it must always be more advantageous to purchase a debt
than to hold cash as a store of wealth.
この必要条件とは将来の利子率に関する不確実性の存在である。利子率とはこの場合、将来の様々な日付を満期とする利子率複合体のことである。というのは、
仮にもし将来のあらゆる時点における支配的な利子率（＝市場利子率）が確実に予知できるとすると、様々な満期を持つ債権の現在の利子率から、あらゆる将来
の利子率が推測できることになり、現代の利子率が将来の利子率の知識と合致するのである。例えば、もし１Ｄｒがｒ年後の１ポンドの現在年１の価値であっ
て、ｎＤｒはｎ年からｒ年後の１ポンドのｎ年における価値となることがわかっているとすると
ｎＤｒ＝１Ｄｎ＋ｒ／１Ｄｎ が成り立つ（＝１Ｄｎ＋ｒはｎ＋ｒ年後の１ポンドの現在年１の価値）。
この式から、今からｎ年後の債権（＝ｎＤｒ）が換金される利子率は現在の利子率複合体のうちの二つ（＝１Ｄｒと１Ｄｎ＋ｒ）によって与えられることにな
る。もし現行の利子率がどの満期の債権についてもプラスなら、富の蓄積としては現金で持つよりは債権を買うほうが常に有利であるということになるにちがい
ない。
If, on the contrary, the future rate of interest is
uncertain<,> we cannot safely infer that ndr will prove to be
equal to 1Dn+r / 1Dn when the time comes. Thus if a need for liquid
cash may conceivably arise before the expiry of n years, there is a
risk of a loss being incurred in purchasing a long-term debt and
subsequently turning it into cash, as compared with holding cash. The
actuarial profit or mathematical expectation of gain calculated in
accordance with the existing probabilities ― if it can be so
calculated, which is doubtful ― must be sufficient to compensate for
the risk of disappointment.
逆に、もし将来の利子率が不確実なら、ｎＤｒは１Ｄｎ＋ｒ／１Ｄｎと等しいと確信を持って言うことができなくなる。つまり、ｎ年が過ぎる前に現金が必要に
なる場合には、現金で持っているのと比べて、長期の債権を購入して換金することは損失のリスクを招くことになる。統計上の利潤あるいは現在の確率に従って
計算された利益の数学的予想 ― もし計算できるならだが、疑わしい ― が損失のリスクを埋め合わせなければならない。
There is, moreover, a further ground for liquidity-preference
which results from the existence of uncertainty as to the future of the
rate of interest, provided that there is an organised market for
dealing in debts. For different people will estimate the prospects
differently and anyone who differs from the predominant opinion as
expressed in market quotations may have a good reason for keeping
liquid resources in order to profit, if he is right, from its turning
out in due course（いずれは判明する） that the 1dr's were in a mistaken
relationship to one another.[3]
さらに、債権を扱うために組織された市場の存在を前提にすれば、将来の利子率の不確実性から来る流動性選好の理由がもう一つある。というのは、将来の予想
については人によって考え方が異なるし、市場の相場に表れている支配的な考え方と異なる考えを持つ人が利益を得るためには、流動資産を持ち続けるのが正し
いことになる。もし彼の予想が当たっていれば、１ｄｒのつながりは間違っていることがいずれ判明するからである[３]。
This is closely analogous to what we have already discussed at
some length in connection with the marginal efficiency of capital. Just
as we found that the marginal efficiency of capital is fixed, not by
the “best” opinion, but by the market valuation as determined by mass
psychology, so also expectations as to the future of the rate of
interest as fixed by mass psychology have their reactions on
liquidity-preference; ― but with this addition that the individual, who
believes that future rates of interest will be above the rates assumed
by the market, has a reason for keeping actual liquid cash,[4] whilst
the individual who differs from the market in the other direction will
have a motive for borrowing money for short periods in order to
purchase debts of longer term. The market price will be fixed at the
point at which the sales of the “bears” and the purchases of the
“bulls” are balanced.
これは我々が資本の限界効率に関して詳しく議論したこととよく似ている。資本の限界効率は最善の意見によって決まるのではなく、大衆心理による市場の評価
によって決まるということを我々はすでに見たが、それと同じく、将来の利子率の予想もまた大衆心理によって決まるもので、それが流動性選好に影響を与える
のである。―しかし、それだけではない。将来の利子率が現在の市場利子率より上ると思う人は、流動的な現金を[４]をもち続けるのが正しいことになる。一
方、それとは反対に将来の利子率が現在の市場利子率より下ると思う人は短期で金を借り入れて長期債権を買おうとするだろう。こうして「弱気筋」の売りと
「強気筋」の買いが均衡する点で、債権の市場価格は決まるのである。
The three divisions of liquidity-preference which we have
distinguished above may be defined as depending on (i) the
transactions-motive, i.e. the need of cash for the current transaction
of personal and business exchanges; (ii) the precautionary-motive, i.e.
the desire for security as to the future cash equivalent of a certain
proportion of total resources; and (iii) the speculative-motive, i.e.
the object of securing profit from knowing better than the market what
the future will bring forth. As when we were discussing the marginal
efficiency of capital, the question of the desirability of having a
highly organised market for dealing with debts presents us with a
dilemma. For, in the absence of an organised market,
liquidity-preference due to the precautionary-motive would be greatly
increased; whereas the existence of an organised market gives an
opportunity for wide fluctuations in liquidity-preference due to the
speculative-motive.
我々が上記に示した流動性選好の三つの分類（＝商取引、富の蓄積、将来の利子率の不確定性）はそれぞれ（１）取引動機、つまり個人や企業が現在取引するた
めの現金の必要性、（２）予備的動機、つまり全資産のある割合を将来における現金として持つことで安心しようとする欲求、（３）投機的動機、つまり将来に
関して市場よりもすぐれた知恵をもっていることで利益を確保しようとする目的、の三つの動機によるものである。我々が資本の限界効率を論じた時と同じく、
債権を扱うための高度に組織された市場をもつことが望ましいかどうかという問題もまた我々に一つのジレンマをもたらす（＝思惑中心の投機が優勢になる）。
というのは、もし組織化された市場がなければ、予備的動機からくる流動性選好はますます大きくなるだろう。その一方、組織化された市場があるために、投機
的な動機から来る流動性選好が大きく変動する機会が生まれているのである。
It may illustrate the argument to point out that, if the
liquidity-preferences due to the transactions-motive and the
precautionary-motive are assumed to absorb a quantity of cash which is
not very sensitive to changes in the rate of interest as such and apart
from（～を考えずにそれ自体として） its reactions on the level of income, so that the
total quantity of money, less this quantity, is available for
satisfying liquidity-preferences due to the speculative-motive, the
rate of interest and the price of bonds have to be fixed at the level
at which the desire on the part of certain individuals to hold cash
(because at that level they feel “bearish” of the future of bonds) is
exactly equal to the amount of cash available for the
speculative-motive.
このことを説明するためには、次の事を指摘するのがよいだろう。取引動機と予備的動機に基づく流動性選好が（所得水準に対する影響は考えずにそれ自体とし
ての）利子率の変化に反応しない大量の現金を吸収して、この量を引いた総貨幣量が投機的動機に基づく流動性選好を満たすために利用可能であるとすると、投
機的動機のためのこの現金量（＝貨幣供給）が、（その水準では債券の将来について弱気であるために）現金を持ちたい人達の欲望（＝貨幣需要）とちょうど一
致するところで、利子率と債券価格が決まるのである。
Thus each increase in the quantity of money must raise the price of
bonds sufficiently to exceed the expectations of some “bull” and so
influence him to sell his bond for cash and join the “bear” brigade.
If, however, there is a negligible demand for cash from the
speculative-motive except for a short transitional interval, an
increase in the quantity of money will have to lower the rate of
interest almost forthwith, in whatever degree is necessary to raise
employment and the wage-unit sufficiently to cause the additional cash
to be absorbed by the transactions-motive and the precautionary-motive.
つまり、貨幣量の増加によって強気筋の予想を超えるほど債券価格が上がると、債券を売って現金化して弱気筋の仲間入りせざるをえないのである。しかし、そ
の投機的動機からの現金需要もごく短い過渡期だけで取るに足らない場合には、貨幣量の増加で利子率は即座に下がらざるをえないが、それは雇用と単位賃金の
引き上げに必要な程度であり、増えた現金は取引動機と予備的動機によって吸収されてしまう。
As a rule, we can suppose that the schedule of
liquidity-preference relating the quantity of money to the rate of
interest is given by a smooth curve which shows the rate of interest
falling as the quantity of money is increased. For there are several
different causes all leading towards this result.
一般に、貨幣量と利子率とを結びつける流動性選好表は貨幣量の増加と利子率の低下が連動することを示す滑らかな曲線になると考えられる。というのは、いくつかの異なった原因があるが全てはこの結果に至るからである。
In the first place, as the rate of interest falls, it is likely,
cet. par., that more money will be absorbed by liquidity-preferences
due to the transactions-motive. For if the fall in the rate of interest
increases the national income, the amount of money which it is
convenient to keep for transactions will be increased more or less
proportionately to the increase in income; whilst, at the same time,
the cost of the convenience of plenty of ready cash in terms of loss of
interest will be diminished. Unless we measure liquidity-preference in
terms of wage-units rather than of money (which is convenient in some
contexts), similar results follow if the increased employment ensuing
on a fall in the rate of interest leads to an increase of wages, i.e.
to an increase in the money-value of the wage-unit. In the second
place, every fall in the rate of interest may, as we have just seen,
increase the quantity of cash which certain individuals will wish to
hold because their views as to the future of the rate of interest
differ from the market views.
まず第一に、利子率が低下すれば、他の条件が同じとして、取引動機の流動性選好によって多くの貨幣が吸収されるだろう。というのは、もし利子率が低下した
ために国民所得が増加したら、取引目的で保有しておくのが好都合な貨幣量が所得の増加に比例して増えるからである。一方、それと同時に、利子率が低下した
おかげで、大量の現金を持つ代償として利子を失う機会費用は低減されている。流動性選好を貨幣ではなく単位賃金数で測ら（ある文脈では便利である）ない限
り、利子率の低下からくる雇用の増加が賃金の上昇をもたらして単位賃金の貨幣価値を増加させるから、同様の結果になる。第二に、今見たように、利子率が低
下するたびに（＝債券価格が上昇）、ある人々が将来の利子率に対する見方が市場の見方と異なるために保有したいと思う現金量が増加する。
Nevertheless, circumstances can develop in which even a large
increase in the quantity of money may exert a comparatively small
influence on the rate of interest. For a large increase in the quantity
of money may cause so much uncertainty about the future that
liquidity-preferences due to the security-motive may be strengthened;
whilst opinion about the future of the rate of interest may be so
unanimous that a small change in present rates may cause a mass
movement into cash. It is interesting that the stability of the system
and its sensitiveness to changes in the quantity of money should be so
dependent on the existence of a variety of opinion about what is
uncertain. Best of all that we should know the future. But if not,
then, if we are to control the activity of the economic system by
changing the quantity of money, it is important that opinions should
differ. Thus this method of control is more precarious in the United
States, where everyone tends to hold the same opinion at the same time,
than in England where differences of opinion are more usual.
それにも関わらず、貨幣量が大きく増えても利子率があまりを影響を受けないような状況もありうる。というのは、貨幣量が大きく増えると将来の不確実性も大
きくなり予備的な動機による流動性選好が強まることがあるからである。その一方、将来の利子率についての考えが全員一致している場合は、現行利子率の少し
の変化でも現金化の動きが一斉に起きかねない。おもしろいことに、経済の安定性および貨幣量の変化に対する経済の敏感さは、不確実性に対する多様な意見が
存在することに依存しているのである。未来が予知できるのが一番いいのだが、それが不可能な場合には、貨幣量を変えることで経済活動を制御するつもりな
ら、多様な意見が存在することが重要である。この点で、合衆国は全員が同時に同じ意見を持つ傾向があるので、多様な意見が存在する英国よりも、この制御方
法はうまくいきそうにない。
III
We have now introduced money into our causal nexus for the first
time, and we are able to catch a first glimpse of the way in which
changes in the quantity of money work their way into the economic
system. If, however, we are tempted to assert that money is the drink
which stimulates the system（経済システム） to activity, we must remind
ourselves that there may be several slips between the cup and the lip.
For whilst an increase in the quantity of money may be expected, cet.
par., to reduce the rate of interest, this will not happen if the
liquidity-preferences of the public are increasing more than the
quantity of money; and whilst a decline in the rate of interest may be
expected, cet. par., to increase the volume of investment, this will
not happen if the schedule of the marginal efficiency of capital is
falling more rapidly than the rate of interest; and whilst an increase
in the volume of investment may be expected, cet. par., to increase
employment, this may not happen if the propensity to consume is falling
off. Finally, if employment increases, prices will rise in a degree
partly governed by the shapes of the physical supply functions, and
partly by the liability of the wage-unit to rise in terms of money. And
when output has increased and prices have risen, the effect of this on
liquidity-preference will be to increase the quantity of money
necessary to maintain a given rate of interest.
第３節
我々は今や初めて因果関係の中に貨幣を導入した。我々は貨幣量の変化が経済の中でどのような働きするかを初めてうかがい知ることができるのである。しか
しながら、貨幣こそは経済に活力を与える飲料であると主張しようと思っても、コップと唇の間には幾多の行き違いが存在することを忘れてはならない。という
のは、他の条件が同じなら、貨幣量が増えると利子率が下がると思われているが、これは社会の流動性選好が増加して、それが貨幣量を上回る場合には成り立た
ないのである。また、他の条件が同じなら、利子率が下がると投資量が増えると思われているが、これは消費性向が下がっている場合には成り立たないのであ
る。最後に、もし雇用が増加すると、物理的な供給関数の形状と、貨幣で測った単位賃金が上昇する傾向によって左右される程度に、物価が上昇する。そして産
出量が増加して物価が上昇した時には、流動性選好が影響を受けて、一定の利子率を維持するために必要な貨幣量が増えるのである。
IV
Whilst liquidity-preference due to the speculative-motive
corresponds to what in my Treatise on Money I called “the state of
bearishness”, it is by no means the same thing. For “bearishness” is
there defined as the functional-relationship, not between the rate of
interest (or price of debts) and the quantity of money, but between the
price of assets and debts, taken together, and the quantity of money.
This treatment, however, involved a confusion between results due to a
change in the rate of interest and those due to a change in the
schedule of the marginal efficiency of capital, which I hope I have
here avoided.
第４節
投機的動機による流動性選好は『貨幣論』では私が「弱気の状態」と呼んだものであるが、両者は同じものではない。というのは、その本では「弱気」とは利子
率（または債権価格）と貨幣量の相関関係ではなく、資産と債権を合わせた価格と貨幣量との関係と定義されているからである。しかし、あの論文は利子率の変
化の結果と資本の限界効率表の変化の結果を混同していた。今回はその混同を避けられたと思う。
V
The concept of Hoarding may be regarded as a first approximation to the
concept of Liquidity-preference. Indeed if we were to substitute
“propensity to hoard” for “hoarding”, it would come to substantially
the same thing. But if we mean by “hoarding” an actual increase in
cash-holding, it is an incomplete idea ― and seriously misleading if it
causes us to think of “hoarding” and “not-hoarding” as simple
alternatives. For the decision to hoard is not taken absolutely or
without regard to the advantages offered for parting with liquidity; ―
it results from a balancing of advantages, and we have, therefore, to
know what lies in the other scale. Moreover it is impossible for the
actual amount of hoarding to change as a result of decisions on the
part of the public, so long as we mean by “hoarding” the actual holding
of cash. For the amount of hoarding must be equal to the quantity of
money (or ― on some definitions ― to the quantity of money minus what
is required to satisfy the transactions-motive); and the quantity of
money is not determined by the public. All that the propensity of the
public towards hoarding can achieve is to determine the rate of
interest at which the aggregate desire to hoard becomes equal to the
available cash. The habit of overlooking the relation of the rate of
interest to hoarding may be a part of the explanation why interest has
been usually regarded as the reward of not-spending, whereas in fact it
is the reward of not-hoarding.
第４節
保蔵（＝金を貯めこむ）という概念は流動性選好という概念と非常に似ているように思えるかもしれない。確かにもし「保蔵」を「保蔵性向」という意味で使う
なら、流動性選好とほぼ同じことになる。しかし、もし「保蔵」を現金所有の増加の意味だとすると、それは不完全であるし、そこから保蔵と非保蔵が単なる選
択肢であると考えるなら全くの誤解である。というのは、保蔵の決定は独立したものではないし、流動性を手放すことへの報酬と無関係ではないからである。―
つまり、保蔵の決定は利益の均衡の結果なのである。したがって、我々は天秤のもう一方には何が乗っているかを知らなければならない。さらに、保蔵の意味が
現金を所有することなら、保蔵量が社会の決定で変化することはあり得ない。というのは、保蔵量は貨幣量（または、ある定義では、取引動機を満たすために必
要な貨幣量を引いた量）と等しくなければならないからである。そして、貨幣量は社会が決めるものではないのである。社会の保蔵性向がなしうることは、全体
の保蔵欲が現金量と等しくなるような利子率を決定することだけである。利子率と保蔵との関係を無視する習慣があるために、利子は消費しないことの報酬だと
一般に見做されているのである。実際には利子は保蔵しないことの報酬なのである。
Author's Footnotes
[1]. Without disturbance to this definition, we can draw the line
between “money” and “debts” at whatever point is most convenient for
handling a particular problem. For example, we can treat as money any
command over general purchasing power which the owner has not parted
with for a period in excess of three months, and as debt what cannot be
recovered for a longer period than this; or we can substitute for
“three months” one month or three days or three hours or any other
period; or we can exclude from money whatever is not legal
tender（法貨、通貨） on the spot. It is often convenient in practice to
include in money time-deposits（定期預金） with banks and, occasionally, even
such instruments（証券） as (e.g.) treasury bills（大蔵省証券）. As a rule, I
shall, as in my Treatise on Money, assume that money is
coextensive（同じ広がりを持つ） with bank deposits（銀行預金）.
[2]. In general discussion, as distinct from specific problems where
the period of the debt is expressly specified, it is convenient to mean
by the rate of interest the complex of the various rates of interest
current for different periods of time, i.e. for debts of different
maturities.
[3]. This is the same point as I discussed in my Treatise on Money
under the designation of the two views and the “bull-bear” position.
[4]. It might be thought that, in the same way, an individual, who
believed that the prospective yield of investments will be below what
the market is expecting, will have a sufficient reason for holding
liquid cash. But this is not the case. He has a sufficient reason for
holding cash or debts in preference to equities; but the purchase of
debts will be a preferable alternative to holding cash, unless he also
believes that the future rate of interest will prove to be higher than
the market is supposing.
著者注
[１] 「貨幣」と「債権」の間の線引は特定の問題を扱うのに便利な場所に引けばよいのであって、それによって利子率のこの定義が影響を受けることはな
い。例えば、貨幣を「３ヶ月を越えて手放すことのなかった一般的な購買力」のことにして、債権を「３ヶ月より長い期間利用できない購買力」としてもよい。
あるいは、この３ヶ月を１ヶ月にしてもいいし、３日にしてもいいし、どんな期間にしてもいいのだ。あるいは貨幣の範疇から現金でない法定通貨を排除しても
よい。あるいは、銀行の定期預金を貨幣の中に含めるのが実用的かもしれない。あるいは場合によっては財務証券のような証券を含めるのも便利だろう。一般的
に、自著『貨幣論』と同じく、私は銀行預金は貨幣のうちに含めて考えることにしている。
[２] 一般的な議論では、債権の期間は明示されている特殊な問題は別として、利子率として様々な期間を持つ様々な現行の利子率の複合体、すなわち様々な満期を持つ債権の利子率複合体を考えるのが便利である。
[３] これは自著『貨幣論』で「二つの見方と『強気・弱気筋』」として論じたのと同じである。
[４] 同様にして、投資物件の見込み収益が市場の予想よりも下回ると思う人は、流動的な現金を保有する充分な理由があると思えるかもしれないが、これは
間違っている。その場合には、株式よりも現金か債権を保有したくなる充分な理由になるだけである。しかし、それと同時に将来の利子率が市場の予想よりも高
くなると思えない場合には、現金保有よりも債権の購入が望ましく思えるだろう。
Chapter 14. The Classical Theory of the Rate of Interest
第１４章 利子率についての古典的理論
I
WHAT is the Classical Theory of the Rate of Interest? It is
something upon which we have all been brought up and which we have
accepted without much reserve until recently. Yet I find it difficult
to state it precisely or to discover an explicit account of it in the
leading treatises of the modern classical school.[1]
第１節
利子率についての古典派の理論はどういうものだろう。我々は古典派の理論と共に成長しその理論を最近までほとんど無条件に受け入れてきた。しかし、それが
どういうものかを正確に記述することは難しいし、近代古典派の主な論文の中にその明確な記述を見つけることも難しい[１]。
It is fairly clear, however, that this tradition has regarded
the rate of interest as the factor which brings the demand for
investment and the willingness to save into equilibrium with one
another. Investment represents the demand for investable resources and
saving represents the supply, whilst the rate of interest is the
“price” of investable resources at which the two are equated. Just as
the price of a commodity is necessarily fixed at that point where the
demand for it is equal to the supply, so the rate of interest
necessarily comes to rest under the play of market forces at the point
where the amount of investment at that rate of interest is equal to the
amount of saving at that rate.
しかし、利子率は古典派の伝統では投資需要と貯蓄志向に相互の均衡をもたらす要素であると見做されてるのは明らかである。投資とは投資可能な資金に対する
需要、貯蓄とはその供給を意味する。それに対して、利子率とはこの二つが一致する投資可能な資金の「価格」である。商品の価格がその需要と供給の一致する
地点で必ず決まるように、市場の力の作用のもとで、利子率は投資量と貯蓄量とがそこで一致する地点で必ず安定するのである。
The above is not to be found in Marshall's Principles in so many
words. Yet his theory seems to be this, and it is what I myself was
brought up on and what I taught for many years to others. Take, for
example, the following passage from his Principles: “Interest, being
the price paid for the use of capital in any market, tends towards an
equilibrium level such that the aggregate demand for capital in that
market, at that rate of interest, is equal to the aggregate stock（資本）
forthcoming at that rate”.[2] Or again in Professor Cassel's Nature and
Necessity of Interest it is explained that investment constitutes the
“demand for waiting” and saving the “supply of waiting”, whilst
interest is a “price” which serves, it is implied, to equate the two,
though here again I have not found actual words to quote. Chapter vi.
of Professor Carver's Distribution of Wealth clearly envisages interest
as the factor which brings into equilibrium the marginal disutility of
waiting with the marginal productivity of capital.[3]
これはそのままマーシャルの『原理』に出てくるわけではない。しかし、彼の利子率の理論はこれだし、私が育ったのも私が教えてきたのもこれである。例え
ば、彼の『原理』から次の文章を引用してみよう。「利子は、市場で資本の使用に対して支払われる代価であって、市場における資本の総需要がその利子率で供
給される総資本ストックと一致するような均衡レベルに向かう。」[２]。あるいは、カッセル教授の『利子の性質と必然性』では、「待忍に対する需要」が投
資であり「待忍からの供給」が貯蓄であるが、一方、利子はこの二つを一致させる価格であるとされている。ただし、ここでも直接そういう言葉を使っているわ
けでない。カーヴァー教授の『富の分配』の第４章では、明らかに、利子は「待忍の限界不効用」と「資本の限界生産性」を均衡させる要因であると見做されて
いる。
Sir Alfred Flux (Economic Principles, p. 95) writes: “If there is
justice in the contentions of our general discussion, it must be
admitted that an automatic adjustment takes place between saving and
the opportunities for employing capital profitably. ... Saving will not
have exceeded its possibilities of usefulness ... so long as the rate
of net interest is in excess of zero.” Professor Taussig (Principles,
vol., ii. p. 29) draws a supply curve of saving and a demand curve
representing “the diminishing productiveness of the several instalments
of capital”, having previously stated (p. 20) that “the rate of
interest settles at a point where the marginal productivity of capital
suffices to bring out the marginal instalment of saving”.[4] Walras, in
Appendix I. (III.) of his Elements d'economie pure, where he deals with
“l'echange d'epargnes contre capitaux neufs”, argues expressly that,
corresponding to each possible rate of interest, there is a sum which
individuals will save and also a sum which they will invest in new
capital assets, that these two aggregates tend to equality with one
another, and that the rate of interest is the variable which brings
them to equality; so that the rate of interest is fixed at the point
where saving, which represents the supply of new capital, is equal to
the demand for it. Thus he is strictly in the classical tradition.
アルフレッド・フラックス卿（『経済原理』９５頁）にはこう書いている。「我々の一般的な議論が正しければ、資本の有利な利用機会と貯蓄との間には自動的
な調整が働くことを認めなければならない・・・利子率がゼロ以上であるかぎり・・・貯蓄がいくら増えても有利さを失うことはない」。タウシング教授（『原
理』第２巻２９頁）は貯蓄の供給曲線と「資本の逐次投入の生産性の逓減」を表す需要曲線を描いているが、その前に（２０頁）「利子率は資本の限界生産性が
貯蓄の限界投入を引き出す地点で決まる」と書いている[４]。ワルラスは『純粋経済学要綱』付録ⅠのⅢの「貯蓄と新資本の交換」を扱っているところで、次
のように書いている。利子率のそれぞれの値に対応して個人が貯蓄する金額と新資本資産に投資する金額が存在すること、この二つの総量は相互に一致する傾向
があること、利子率はこの二つを一致させる変数であること、その結果、利子率は新投資の供給である貯蓄が新投資に対する需要と等しくなる点で決まると。つ
まり、彼は厳密なほどに古典派の伝統に従っているのである。
Certainly the ordinary man ― banker, civil servant or politician
― brought up on the traditional theory, and the trained economist also,
has carried away with him the idea that whenever an individual performs
an act of saving he has done something which automatically brings down
the rate of interest, that this automatically stimulates（増加させる） the
output of capital, and that the fall in the rate of interest is just so
much as is necessary to stimulate the output of capital to an extent
which is equal to the increment of saving; and, further, that this is a
self-regulatory process of adjustment which takes place without the
necessity for any special intervention or grandmotherly care on the
part of the monetary authority. Similarly ― and this is an even more
general belief, even to-day ― each additional act of investment will
necessarily raise the rate of interest, if it is not offset by a change
in the readiness to save.
確かに伝統的理論で成長した一般人―銀行家や役人や政治家―も専門の経済学者も、次のような考え方をもっている。つまり、「個人が貯蓄すると自動的に利子
率が下がり、これが資本の産出量を自動的に増加させる」。また「利子率は資本の産出量が増加して貯蓄の増加と等しくなるまで必然的に下がる」。さらに「こ
の過程は自動的な調整過程であって、貨幣当局による介入やお節介を必要としない」という考え方である。同様に、「もし貯蓄志向の変化によって相殺されない
場合には、投資の増やす行為は必ず利子率を引き上げる」という考え方は、さらに一般的なものである。
Now the analysis of the previous chapters will have made it
plain that this account of the matter must be erroneous. In tracing to
its source the reason for the difference of opinion, let us, however,
begin with the matters which are agreed.
これまでの章の分析によれば、問題に対するこの記述が間違っていることは明らかだろう。しかし、この考えの違いの原因を根源まで遡りながら、まずは意見が一致している事から始めよう。
Unlike the neo-classical school, who believe that saving and
investment can be actually unequal, the classical school proper has
accepted the view that they are equal. Marshall, for example, surely
believed, although he did not expressly say so, that aggregate saving
and aggregate investment are necessarily equal. Indeed, most members of
the classical school carried this belief much too far; since they held
that every act of increased saving by an individual necessarily brings
into existence a corresponding act of increased investment. Nor is
there any material difference, relevant in this context, between my
schedule of the marginal efficiency of capital or investment
demand-schedule and the demand curve for capital contemplated by some
of the classical writers who have been quoted above. When we come to
the propensity to consume and its corollary the propensity to save, we
are nearer to a difference of opinion, owing to the emphasis which they
have placed on the influence of the rate of interest on the propensity
to save.
貯蓄と投資は実際には一致しないと信じる新古典派とちがって、古典派の学者たちはこの二つが一致するという考えを受け入れてきた。例えば、マーシャルは自
分ではそうは言わないが、総貯蓄と総投資は必然的に一致すると確かに信じていた。なるほど、多くの古典派経済学者はこの信念を推し進めすぎている。という
のは、貯蓄を増やすあらゆる行為は必然的にそれに対応して投資を増やす行為を存在させると信じているからである。また、この点に関して、私の資本の限界効
率表あるいは投資需要表と、ここで引用した古典派の学者たちが考える資本の需要曲線との間に大きな違いはない。しかし、消費性向とその裏返しである貯蓄性
向の話になると、見解の相違点に近づいてくる。彼らは利子率が貯蓄性向に与える影響を強調するからである。
But they would, presumably, not wish to deny that the level of income
also has an important influence on the amount saved; whilst I, for my
part, would not deny that the rate of interest may perhaps have an
influence (though perhaps not of the kind which they suppose) on the
amount saved out of a given income. All these points of agreement can
be summed up in a proposition which the classical school would accept
and I should not dispute; namely, that, if the level of income is
assumed to be given, we can infer that the current rate of interest
must lie at the point where the demand curve for capital corresponding
to different rates of interest cuts the curve of the amounts saved out
of the given income corresponding to different rates of interest.
しかし、おそらく彼らは所得水準が貯蓄額に重要な影響を与えることを否定するつもりはない。一方、私としても、利子率が所得から貯蓄される割合に影響（た
だし彼らが考える影響ではない）を与えることを否定するつもりはない。これらの意見の一致点はどちらも、古典派の学者たちが受け入れて私も拒否しない一つ
の命題に要約できる。すなわち、もし所得水準が一定なら、様々な利子率に対応する資本の需要曲線が、所得から貯蓄される量を様々な利子率と結びつける曲線
と交わる点で現行利子率が決まるという命題である。
But this is the point at which definite error creeps into the
classical theory. If the classical school merely inferred from the
above proposition that, given the demand curve for capital and the
influence of changes in the rate of interest on the readiness to save
out of given incomes, the level of income and the rate of interest must
be uniquely correlated, there would be nothing to quarrel with.
Moreover, this proposition would lead naturally to another proposition
which embodies an important truth; namely, that, if the rate of
interest is given as well as the demand curve for capital and the
influence of the rate of interest on the readiness to save out of given
levels of income, the level of income must be the factor which brings
the amount saved to equality with the amount invested. But, in fact,
the classical theory not merely neglects the influence of changes in
the level of income, but involves formal error.
しかし、まさにこの点で古典派の理論にはっきり間違いが入り込んで来ている。もし古典派の学者たちがこの命題から推測して、資本の需要曲線と、所得水準
と、貯蓄志向に対する利子率の変化の影響を一定とするとき、所得水準と利子率が一意的に相関しているというなら、何も文句はない。さらに、当然この命題は
重要な真実を体現しているもうひとつの命題に至る。それは即ち、資本の需要曲線と、所得水準と、貯蓄志向に対する利子率の変化の影響だけでなく、利子率も
一定なら、その所得水準が貯蓄量と投資量を一致させる要素である。しかし、実際には、古典派の理論は所得水準の変化の影響を無視するだけでなく、形式的な
誤りも犯している。
For the classical theory, as can be seen from the above
quotations, assumes that it can then proceed to consider the effect on
the rate of interest of (e.g.) a shift in the demand curve for capital,
without abating or modifying its assumption as to the amount of the
given income out of which the savings are to be made. The independent
variables of the classical theory of the rate of interest are the
demand curve for capital and the influence of the rate of interest on
the amount saved out of a given income; and when (e.g.) the demand
curve for capital shifts, the new rate of interest, according to this
theory, is given by the point of intersection between the new demand
curve for capital and the curve relating the rate of interest to the
amounts which will be saved out of the given income. The classical
theory of the rate of interest seems to suppose that, if the demand
curve for capital shifts or if the curve relating the rate of interest
to the amounts saved out of a given income shifts or if both these
curves shift, the new rate of interest will be given by the point of
intersection of the new positions of the two curves.
というのは、古典派の理論は、先の引用からも分かるように、資本の需要曲線のシフトが利子率に与える影響を考える時に、所得水準が一定という想定を変え
ないでいいと考えているからである。利子率の古典派理論の独立変数は、資本の需要曲線と、貯蓄志向に対する利子率の変化の影響である。そして資本の需要曲
線がシフトした時には、この理論によれば、新たな利子率は、新たな資本の需要曲線と、所得から貯蓄される量を様々な利子率と結びつける曲線と交わる点で得
られる。利子率の古典派理論では、資本の需要曲線がシフトするか、所得から貯蓄される量を様々な利子率と結びつける曲線がシフトするか、両方の曲線がシフ
トする場合には、この二つの曲線の新たな交点によって新たな利子率が得られるというのである。
But this is a nonsense theory. For the assumption that income is
constant is inconsistent with the assumption that these two curves can
shift independently of one another. If either of them shift, then, in
general, income will change; with the result that the whole schematism
based on the assumption of a given income breaks down. The position
could only be saved by some complicated assumption providing for an
automatic change in the wage-unit of an amount just sufficient in its
effect on liquidity-preference to establish a rate of interest which
would just offset the supposed shift, so as to leave output at the same
level as before. In fact, there is no hint to be found in the above
writers as to the necessity for any such assumption; at the best it
would be plausible only in relation to long-period equilibrium and
could not form the basis of a short-period theory; and there is no
ground for supposing it to hold even in the long-period. In truth, the
classical theory has not been alive to the relevance of changes in the
level of income or to the possibility of the level of income being
actually a function of the rate of the investment.
しかし、これはナンセンスな理論である。というのは、所得が一定であるという想定は、この二つの曲線が互いに独立してシフトするという想定と両立しないか
らである。もしどちらか一方がシフトしたら、ふつう所得は変化する。その結果、所得を一定とする全体の図式は崩壊するのである。この図式を救えるのは、あ
る種の複雑な想定だけである。それは単位賃金が自動的に変化して流動性選好に影響を与えて、曲線のシフトを相殺するような利子率をもたらして、その結果、
産出量を以前と同じに保つと想定することである。実際、上記の学者たちはそんな想定が必要だとは考えているようには見えない。うまくいっても、そのような
想定は長期均衡との関連ではありうるが、短期理論の基礎とは成り得ないし、長期においても維持できると考える理由はない。事実、古典派理論は所得水準の変
化の重要性やあるいは所得水準が投資量の関数である可能性には気づいていなかったのである。
The above can be illustrated by a diagram[5] as follows:
このことは次のグラフで説明できる。グラフは略
In this diagram the amount of investment (or saving) I is
measured vertically, and the rate of interest r horizontally. X1X1' is
the first position of the investment demand-schedule, and X2X2' is a
second position of this curve. The curve Y1 relates the amounts saved
out of an income Y1 to various levels of the rate of interest, the
curves Y2, Y3, etc., being the corresponding curves for levels of
income Y2, Y3, etc. Let us suppose that the curve Y1 is the Y-curve
consistent with an investment demand-schedule X1X1' and a rate of
interest r1. Now if the investment demand-schedule shifts from X1X1' to
X2X2', income will, in general, shift also. But the above diagram does
not contain enough data to tell us what its new value will be; and,
therefore, not knowing which is the appropriate Y-curve, we do not know
at what point the new investment demand-schedule will cut it. If,
however, we introduce the state of liquidity-preference and the
quantity of money and these between them tell us that the rate of
interest is r2, then the whole position becomes determinate.
このグラフでは投資量（あるいは貯蓄量）Ｉを横軸に、利子率ｒを縦軸におく。Ｘ１Ｘ１'は投資需要表（＝資本の需要曲線）の最初の位置であり、Ｘ２Ｘ２'
はこの曲線の二番目の位置である。曲線Ｙ１は所得Ｙ１から貯蓄される量を様々な利子率と結びつける曲線である。曲線Ｙ２、Ｙ３等々も同様に所得レベル
Ｙ２、Ｙ３等々に対応している。曲線Ｙ１は投資需要表Ｘ１Ｘ１'と利子率ｒ１と一致するＹ曲線であるとする。いま投資需要表がＸ１Ｘ１'からＸ２Ｘ２'へ
シフトすると、一般的には所得もシフトする。しかし、このグラフでは充分なデータがないので所得の新しい値は分からない。したがって、Ｙ曲線のどれが正し
い曲線かわからないと、新たな投資需要表がどこでＹ曲線と交わるかわからない。しかし、もし我々が流動性選好の状態と貨幣量を導入して、この二つから利子
率がｒ２であることが分かると、全ての位置が確定する。
For the Y-curve which intersects X2X2' at the point vertically above
r2, namely, the curve Y2, will be the appropriate curve. Thus the
X-curve and the Y-curves tell us nothing about the rate of interest.
They only tell us what income will be, if from some other source we can
say what the rate of interest is. If nothing has happened to the state
of liquidity-preference and the quantity of money, so that the rate of
interest is unchanged, then the curve Y'2 which intersects the new
investment demand-schedule vertically below the point where the curve
Y1 intersected the old investment demand-schedule will be the
appropriate Y-curve, and Y'2 will be the new level of income.
というのは、Ｘ２Ｘ２'とｒ２の上の点で交わるＹ曲線、つまり曲線Ｙ２が正しい曲線だとわかるからである。つまり、Ｘ曲線とＹ曲線は利子率については何も
教えてくれない。そこから所得がわかるのは何らかの資料から利子率が分かった場合だけである。もし流動性選好の状態と貨幣量に何も起こらず、利子率に変化
がなかったら、新たな投資需要表と曲線Ｙ１が元の投資需要表と交わる点の下で交わる曲線Ｙ２'が正しいＹ曲線だということになって、曲線Ｙ２'が新たな所
得レベルとなる。
Thus the functions used by the classical theory, namely, the
response of investment and the response of the amount saved out of a
given income to change in the rate of interest, do not furnish material
for a theory of the rate of interest; but they could be used to tell us
what the level of income will be, given (from some other source) the
rate of interest; and, alternatively, what the rate of interest will
have to be, if the level of income is to be maintained at a given
figure (eg. the level corresponding to full employment).
つまり、古典派理論が使う変動、すなわち、投資の利子率の変化に対する反応（＝資本の需要曲線）、所得から貯蓄される量の利子率の変化に対する反応は、
利子率の理論のための材料を提供しない。しかし（ある別の理由から）利子率が一定であるなら、この二つを使って所得水準を知ることが出来る。また逆に、も
し所得水準が一定（例えば完全雇用に対応する水準）に保たれるなら、この二つを使って利子率を知ることが出来る。
The mistake originates from regarding interest as the reward for
waiting as such, instead of as the reward for not-hoarding; just as the
rates of return on loans or investments involving different degrees of
risk, are quite properly regarded as the reward, not of waiting as
such, but of running the risk. There is, in truth, no sharp line
between these and the so-called “pure” rate of interest, all of them
being the reward for running the risk of uncertainty of one kind or
another. Only in the event of money being used solely for transactions
and never as a store of value, would a different theory become
appropriate.[6]
間違いの原因は、利子を保蔵の報酬ではなく、待忍そのものの報酬と見なすことから来ている。それは、様々なレベルのリスクをもつ借り入れや投資からの利益
を、リスクの報酬ではなく、単なる待忍の報酬と見なすのが間違っているのと同じである。本当は、投資からの利益といわゆる純粋利子率との間に明確な区切り
はない。どちらもある種の不確定性のリスクを冒すことの報酬なのである。貨幣が取引目的だけに使われ、価値の保有のために使われないときだけ、私の理論と
は違う理論が正しいことになるだろう[６]。
There are, however, two familiar points which might, perhaps,
have warned the classical school that something was wrong. In the first
place, it has been agreed, at any rate since the publication of
Professor Cassel's Nature and Necessity of Interest, that it is not
certain that the sum saved out of a given income necessarily increases
when the rate of interest is increased; whereas no one doubts that the
investment demand-schedule falls with a rising rate of interest. But if
the Y-curves and the X-curves both fall as the rate of interest rises,
there is no guarantee that a given Y-curve will intersect a given
X-curve anywhere at all. This suggests that it cannot be the Y-curve
and the X-curve alone which determine the rate of interest.
しかし、二つのよく知られたことがあって、そのお陰で古典派の学者たちは何かが間違っていることに気づいてよかったのだ。第一に、カッセル教授の『利子の
性質と必然性』の出版以来、一定の所得から貯蓄される量は利子率の増加につれて必ず増える（＝Ｙ曲線は右上がり）とは言えなくなっているのは、誰もが認め
ているのである。その一方で、投資需要表（＝Ｘ曲線）は利子率の上昇とともに下降する（＝右下がり）ことは誰も疑わない。しかし、利子率の上昇とともにＹ
曲線とＸ曲線がともに下降した場合に（＝共に右下がり）、Ｙ曲線とＸ曲線がどこかで交差するという保証はないのである。つまり、これは利子率を決定するこ
とはＹ曲線とＸ曲線だけでは出来ないということである。
In the second place, it has been usual to suppose that an
increase in the quantity of money has a tendency to reduce the rate of
interest, at any rate in the first instance and in the short period.
Yet no reason has been given why a change in the quantity of money
should affect either the investment demand-schedule or the readiness to
save out of a given income. Thus the classical school have had quite a
different theory of the rate of interest in Volume I dealing with the
theory of value from what they have had in Volume II dealing with the
theory of money. They have seemed undisturbed by the conflict and have
made no attempt, so far as I know, to build a bridge between the two
theories. The classical school proper, that is to say（少なくとも）; since it
is the attempt to build a bridge on the part of the neo-classical
school which has led to the worst muddles of all. For the latter have
inferred that there must be two sources of supply to meet the
investment demand-schedule; namely, savings proper, which are the
savings dealt with by the classical school, plus the sum made available
by any increase in the quantity of money (this being balanced by some
species of levy on the public, called “forced saving” or the like).
第二に、貨幣量の増加は少なくとも最初と短期間は利子率を下げる傾向があると普通は思われている。しかし、なぜ貨幣量が投資需要表や貯蓄志向に影響を与え
るか、その理由を古典派の学者たちは提供していない。つまり、古典派の学者たちは価値の理論を扱う第一巻と貨幣の理論を扱う第二巻で利子率について別々の
理論を立ててきたのだ。私の知るかぎり、彼らはこの矛盾を気にして来なかったし、この二つの理論の間を結ぶ橋を作ろうとして来なかった。少なくとも本来の
古典派経済学者はそうである。なぜなら、新古典派経済学はこの橋を作ろうとして最悪の泥沼に陥っているからである。というのは、新古典派経済学は投資需要
表に合わすために二つの投資源があるに違いないと推測した。すなわち、古典派が扱う本来の貯蓄のほかに貨幣量の増加によって利用可能となった金額（これは
「強制貯蓄」などと呼ばれる社会による一種の課税に相当する）である。
This leads on to the idea that there is a “natural” or “neutral”[6] or
“equilibrium” rate of interest, namely, that rate of interest which
equates investment to classical savings proper without any addition
from “forced savings”; and finally to what, assuming they are on the
right track at the start, is the most obvious solution of all, namely,
that, if the quantity of money could only be kept constant in all
circumstances, none of these complications would arise, since the evils
supposed to result from the supposed excess of investment over savings
proper would cease to be possible. But at this point we are in deep
water. “The wild duck has dived down to the bottom ― as deep as she can
get ― and bitten fast hold of the weed and tangle and all the rubbish
that is down there, and it would need an extraordinarily clever dog to
dive after and fish her up again.”
これがさらに「自然利子率」、「中立利子率」[６]、「均衡利子率」があるという考えに至る。つまり、投資と古典派のいう本来の貯蓄（強制貯蓄を含まな
い）を等しくさせる利子率である。そして最後に、もし彼らの出発点が正しければ、すべての解決に至るのである。それは、貨幣量があらゆる状況において一定
に保てるならば、こうした難しい問題は一切発生しない。なぜなら、投資が本来の貯蓄を上回ることから来る害悪は存在しなくなるから、というのである。しか
し、ここで我々は深い水の中に落ち込んでしまう。「野鴨は水底にどこまでも潜り込んだ。そしてそこの水草や藻やゴミに噛みついてしまった。その鴨をもうい
ちど水中から引き上げるには、とてつもなく賢い犬が飛び込むしかなかった」。
Thus the traditional analysis is faulty because it has failed to
isolate correctly the independent variables of the system（経済システム）.
Saving and Investment are the determinates of the system, not the
determinants. They are the twin results of the system's determinants,
namely, the propensity to consume, the schedule of the marginal
efficiency of capital and the rate of interest. These determinants are,
indeed, themselves complex and each is capable of being affected by
prospective changes in the others. But they remain independent in the
sense that their values cannot be inferred from one another. The
traditional analysis has been aware that saving depends on income but
it has overlooked the fact that income depends on investment, in such
fashion that, when investment changes, income must necessarily change
in just that degree which is necessary to make the change in saving
equal to the change in investment.
つまり、古典派の分析は欠陥品なのだ。なぜなら、それは経済の独立変数を正確に取り出すことに失敗しているからである。貯蓄と投資は経済の被決定要因で
あって、決定要因ではない。それらは経済の決定要因である消費性向と資本の限界効率と利子率の結果である。これらの決定要因は確かにそれ自身複雑であり、
自身以外の二つの変化の予想に影響される。しかし、これらのそれぞれの値は他の値からは相互に推測できないという意味では、それらは独立である。古典派の
分析は貯蓄が所得に依存することは知っていたが、所得が投資に依存することを見逃した。つまり、投資が変化すると所得は必然的に変化せざるを得ないので、
貯蓄の変化は投資の変化に必然的に一致することになるのである。
Nor are those theories more successful which attempt to make the
rate of interest depend on “the marginal efficiency of capital”. It is
true that in equilibrium the rate of interest will be equal to the
marginal efficiency of capital, since it will be profitable to increase
(or decrease) the current scale of investment until the point of
equality has been reached. But to make this into a theory of the rate
of interest or to derive the rate of interest from it involves a
circular argument, as Marshall discovered after he had got half-way
into giving an account of the rate of interest along these lines.[8]
For the “marginal efficiency of capital” partly depends on the scale of
current investment, and we must already know the rate of interest
before we can calculate what this scale will be. The significant
conclusion is that the output of new investment will be pushed to the
point at which the marginal efficiency of capital becomes equal to the
rate of interest; and what the schedule of the marginal efficiency of
capital tells us, is, not what the rate of interest is, but the point
to which the output of new investment will be pushed, given the rate of
interest.
また、利子率を「資本の限界効率」に依存させようとする理論もそれよりましとはいえない。確かに均衡状態では利子率は資本の限界効率に等しくなる。この二
つが等しくなるまで現行の投資規模を増やす（あるいは減らす）のが有利だからである。しかし、ここから利子率の理論を作ろうとしたり、ここから利子率を導
き出そうとすると、循環論法に陥ることになる。それはマーシャルがこの考え方にそって利子率を説明しようとして途中で気づいたことである[８]。というの
は、「資本の限界効率」は現行の投資規模に一部は依存し、しかも、この投資規模を計算するためにはあらかじめ利子率を知っておく必要があるからである。そ
こから引き出される有意義な結論は、新たな投資の産出量は、資本の限界効率が利子率と等しくなるところまで拡大するということである。そして、資本の限界
効率表が我々に教えてくれることは、利子率がいくらであるかではなく、所与の利子率のもとで新投資の産出量がどこまで拡大するか、なのである。
The reader will readily appreciate that the problem here under
discussion is a matter of the most fundamental theoretical significance
and of overwhelming practical importance. For the economic principle,
on which the practical advice of economists has been almost invariably
based, has assumed, in effect, that, cet. par., a decrease in spending
will tend to lower the rate of interest and an increase in investment
to raise it. But if what these two quantities determine is, not the
rate of interest, but the aggregate volume of employment, then our
outlook on the mechanism of the economic system will be profoundly
changed. A decreased readiness to spend will be looked on in quite a
different light if, instead of being regarded as a factor which will,
cet. par., increase investment, it is seen as a factor which will, cet.
par., diminish employment.
読者はここで扱っている問題は最も基本的な理論上の意義をもち、実際上も圧倒的な重要性を持っていることを容易に理解してくれるだろう。というのは、経済
学者の実際上の助言が殆ど常に基づいている経済原理は、他の条件が同じなら「支出の減少は利子率を下げる傾向があり、投資の増加は利子率を引き上げる傾向
がある」と想定している。しかし、もしこの二つの量から決まるのが利子率ではなく総雇用量であるなら、我々の経済の仕組みに対する見方は大幅に変わるだろ
う。また、もし支出性向の減少が、他の条件が同じなら投資を増やす要素であると見るかわりに、他の条件が同じなら雇用を減らす要因であると見るならば、支
出性向はまったく違う観点から眺められることになる。
Author's Footnotes
[1]. See the Appendix to this Chapter for an abstract of what I have been able to find.
[2]. Cf. Appendix p. 186 below for a further discussion of this passage.
[3]. Prof. Carver's discussion of Interest is difficult to follow (1)
through his inconsistency as to whether he means by “marginal
productivity of capital” quantity of marginal product or value of
marginal product, and (2) through his making no attempt to define
quantity of capital.
[4]. In a very recent discussion of these problems (“Capital, Time and
the Interest Rate”, by Prof. F. H. Knight, Economica, August 1932), a
discussion which contains many interesting and profound observations on
the nature of capital, and confirms the soundness of the Marshallian
tradition as to the uselessness of the Boehm-Bawerkian analysis, the
theory of interest is given precisely in the traditional, classical
mould. Equilibrium in the field of capital production means, according
to Prof. Knight, “such a rate of interest that savings flow into the
market at precisely the same time-rate or speed as they flow into
investment producing the same net rate of return as that which is paid
savers for their use”.
[5]. This diagram was suggested to me by Mr. R. F. Harrod. Cf. also a
partly similar schematism by Mr. D. H. Robertson, Economic Journal,
December 1934, p. 652.
[6]. Cf. Chapter 17 below.
[7]. The “neutral” rate of interest of contemporary economists is
different both from the “natural” rate of Boehm-Bawerk and from the
“natural” rate of Wicksell.
[8]. See the Appendix to this Chapter.
著者注
[１] 私が理解したことの要約はこの章の付録を見よ。
[２] この一節の詳細な議論はこの章の付録の１８６頁を参照。
[３] カーヴァー教授の利子の議論にはついて行けない。というのは、第一に、「資本の限界生産性」が限界生産量を意味しているのか限界生産価格を意味しているのかはっきりしないからであり、第二に、資本量を一切定義しようとしないからである。
[４] この問題の最新の議論（Ｆ．Ｈ．ナイト教授の「資本、時間、利子率」『エコノミカ』１９３２年８月号）では、資本の性格について非常に深淵で興味
深い観察が行われていて、ベーム・バーヴェルク式の分析の無用さに対するマーシャルの伝統の正しさを確認しており、利子理論がまさに伝統的古典的枠組みの
中で表わされている。資本生産の分野での均衡状態とは、ナイト教授によれば「貯蓄が市場に流入するスピードと貯蓄が投資に流入するスピードが同じで、貯蓄
した人に貯蓄の対価として支払われるのと同じ収益額がその投資によってもたらされるような利子率のことである」。
[５] このグラフはＲ．Ｆ．はロッド氏に教わったものである。『エコノミック・ジャーナル』１９３４年１２月号６５２頁のＤ．Ｈ．ロバートソン氏の同様の図も参照。
[６] １７章参照。
[７] 現代の経済学者の「中立利子率」はベーム・バーヴェルクの「自然利子率」ともヴィックセルの「自然利子率」とも異なるものである。
[８] この章の付録を参照。
Appendix to Chapter 14. Appendix on the Rate of Interest in Marshall's
“Principles of Economics”, Ricardo's “Principles of Political Economy”,
and elsewhere
I
THERE is no consecutive discussion of the rate of interest in
the works of Marshall, Edgeworth or Professor Pigou, ― nothing more
than a few obiter dicta（傍論）. Apart from the passage already quoted
above (p. 139) the only important clues to Marshall's position on the
rate of interest are to be found in his Principles of Economics (6th
edn.), Book VI. p. 534 and p. 593, the gist of which is given by the
following quotations:
第１４章への補足
第１節
マーシャル、エッジワース、ピグー教授の著書には利子率についての一貫した議論は全く存在しない。あるのは二三の傍論だけである。マーシャルの利子率につ
いての立場を知る鍵となる重要な文章は先に引用した（１１章第２節１３９頁）もの以外では、彼の『経済原理』（第６版）の６巻５３４頁と５９３頁にあるも
のだけである。その要点を以下の引用で示す。
“Interest, being the price paid for the use of capital in any
market, tends towards an equilibrium level such that the aggregate
demand for capital in that market, at that rate of interest, is equal
to the aggregate stock[1] forthcoming there at that rate. If the
market, which we are considering, is a small one ― say a single town,
or a single trade（産業） in a progressive country ― an increased demand
for capital in it will be promptly met by an increased supply drawn
from surrounding districts or trades. But if we are considering the
whole world, or even the whole of a large country, as one market for
capital, we cannot regard the aggregate supply of it as altered quickly
and to a considerable extent by a change in the rate of interest. For
the general fund of capital is the product of labour and waiting; and
the extra work,[2] and the extra waiting, to which a rise in the rate
of interest would act as an incentive, would not quickly amount to
much, as compared with the work and waiting, of which the total
existing stock of capital is the result. An extensive increase in the
demand for capital in general will therefore be met for a time not so
much by an increase of supply, as by a rise in the rate of interest;
[3] which will cause capital to withdraw itself partially from those
uses in which its marginal utility is lowest. It is only slowly and
gradually that the rise in the rate of interest will increase the total
stock of capital” (p. 534).
「利子は、市場で資本の使用に対して支払われる代価であって、市場における資本の総需要がその利子率で供給される総資本ストック[１]と一致するような均
衡レベルに向かう。もし我々の考える市場が小さいもの―例えば一つの町あるいは先進国の一つの産業―なら、資本需要の増加は周辺地域あるいは周辺産業から
引き出された供給の増加でただちに満たされるだろう。しかし、もし我々が資本市場として全世界、あるいは大きな国全体を考えるときには、資本需要を満たす
ために資本の総供給が利子率の変化によって急激に大きく変化すると考えることは出来ない。資本となる一般的な資金は労働と待忍（＝貯蓄）の産物であり、利
子率の上昇がインセンティブとなって、労働の増加[２]と待忍の増加があっても、それは現状の資本ストックを生み出した労働と待忍に比べると、急に大きな
量になることはない。そこで、一般的な資本需要の大幅な増加を満たすのは、当面は供給の増加ではなく利子率の上昇なのである[３]。利子率の上昇によっ
て、資本の限界効用が最低な分野から資本が部分的に引き出されるのである。ただ利子率の上昇によって総資本ストックが増加するテンポは非常にゆっくりして
いるだけなのである。（ｐ５３４）」（＝資本需要は小さな国では供給の増加によって満たされるが、大きな国では供給の増加ではなく利子率の上昇によって満
たされるが時間がかかる）
“It cannot he repeated too often that the phrase 'the rate of interest'
is applicable to old investments of capital only in a very limited
sense.[4] For instance, we may perhaps estimate that a trade capital of
some seven thousand millions is invested in the different trades of
this country at about 3 per cent net interest. But such a method of
speaking, though convenient and justifiable for many purposes, is not
accurate. What ought to be said is that, taking the rate of net
interest on the investments of new capital in each of those trades
[i.e. on marginal investments] to be about 3 per cent; then the
aggregate net income rendered by the whole of the trade-capital
invested in the various trades is such that, if
capitalized（資本の割引現在価値を出す） at 33 years' purchase（毎年の収益） (that is, on the
basis of interest at 3 per cent), it would amount to some seven
thousand million pounds. For the value of the capital already invested
in improving land or erecting a building<,> in making a railway
or a machine, is the aggregate discounted value of its estimated future
net incomes [or quasi-rents]; and if its prospective income-yielding
power should diminish, its value would fall accordingly and would be
the capitalised value of that smaller income after <allowing for>
depreciation” (p. 593).
「『利子率』という言葉は古い資本投資に対しては非常に限られた意味でしか使えないということは、いくら繰り返してもよい[４]。たとえば、『約７０億の
産業資本がこの国の様々な産業に約３％の純利子率で投資されている』と推測することがあるかもしれない。しかし、そのような言い方は、多くの目的に便利で
有効だけれども、不正確である。正しい言い方は、『それらの産業の各々に対する新資本の投資（つまり限界投資）の純利子率を約３％とすると、様々な産業に
投資された産業資本全体によってもたらされる総純所得は、毎年の収益の３３年分（つまり利子率３％）で割引現在価値を計算すると約７０億になる（←予想収
益／利子率＝予想収益÷０.０３＝予想収益×１００÷３＝予想収益×３３）』である。というのは、土地を整備したりビルを建てたり鉄道を引いたり機械を
作ったりすることに投資された資本の価値は、推定される将来の純所得（あるいは準地代）の総割引価値現在価値だからである。そして、もし資本の見込所得収
益力が減るとそれに応じて資本の価値も減るが、その価値は減価償却を差し引いて減った所得の割引現在価値となる。」（５９３頁）
In his Economics of Welfare, (3rd edn.), p. 163, Professor Pigou
writes: “The nature of the service of 'waiting' has been much
misunderstood. Sometimes it has been supposed to consist in the
provision of money, sometimes in the provision of time, and, on both
suppositions, it has been argued that no contribution whatever is made
by it to the dividend. Neither supposition is correct. 'Waiting' simply
means postponing consumption which a person has power to enjoy
immediately, thus allowing resources, which might have been destroyed,
to assume the form of production instruments.[5] ... The unit of
'waiting ' is, therefore, the use of a given quantity of resources[6] ―
for example, labour or machinery ― for a given time. ... In more
general terms we may say that the unit of waiting is a year-value unit,
or, in the simpler, if less accurate, language of Dr. Cassel, a
year-pound. ... A caution may be added against the common view that the
amount of capital accumulated in any year is necessarily equal to the
amount of 'savings' made in it. This is not so, even when savings are
interpreted to mean net savings, thus eliminating the savings of one
man that are lent to increase the consumption of another, and when
temporary accumulations of unused claims upon services in the form of
bank-money are ignored; for many savings which are meant to become
capital in fact fail of their purpose through misdirection into
wasteful uses.”[7]
ピグー教授はその著『厚生経済学』（第３版）の１６３頁で次のように書いている。「『待忍』の役割の性格は誤解されてきた。時にはそれは貨幣的備えである
と思われ、時には時間的備えであると思われ、どちらの考え方をしても、分配分（＝所得）に対しては何の貢献もしていないと主張されてきた。しかしどちらの
考え方も正しくない。『待忍』とは単に今すぐできる消費を延期することであって、失われたかもしれない資源に生産手段の姿をとること許すのである
[５]。・・したがって『待忍』の単位は一定資源量[６]―例えば、労働や機械―の一定時間の利用である。・・もっと一般的な言葉でいえば、待忍の単位と
は一年間の価値単位。あるいは精度の低いもっと簡単なキャッセル教授の言葉を使えば、一年間のポンド数である。・・ある年に蓄えられた資本量はその年の
「貯蓄量」と必然的に等しいという一般的な考え方には要注意だ。これは正しくない。たとえ、他人の消費を増やすために貸し出される貯蓄を除外して、貯蓄を
純貯蓄に限るとしても、また、未使用の用役に対する権利を銀行貨幣の形で一時的に蓄えたものを除外するとしても、そうである。なぜなら、資本になるはずの
多くの貯蓄は実際には無駄な用途に誤用されて、資本になれずに終わるからである[７]。」
Professor Pigou's only significant reference to what determines
the rate of interest is, I think, to be found in his Industrial
Fluctuations (1st edn.), pp. 251-3, where he controverts（反駁する） the view
that the rate of interest, being determined by the general conditions
of demand and supply of real capital ' lies outside the central or any
other bank's control. Against this view he argues that: “When bankers
create more credit for business men, they make, in their interest,
subject to the explanations given in chapter xiii. of part i.,[8] a
forced levy of real things from the public, thus increasing the stream
of real capital available for them, and causing a fall in the real rate
of interest on long and short loans alike. It is true, in short, that
the bankers' rate for money is bound by a mechanical tie to the real
rate of interest on long loans; but it is not true that this real rate
is determined by conditions wholly outside bankers' control.”
何が利子率を決めるかについてのピグー教授の唯一の明確な言及は、教授の『産業変動論』（初版）の２５１～３頁に見つけることが出来ると思われる。そこで
彼は「利子率は現物資本の需要と供給の一般的条件によって決まるので中央銀行だろうがどの銀行だろうが利子率をコントロールすることは出来ない」とする考
え方を否定している。この考え方に対して彼は言っている。「銀行家が実業家のために信用創造を増加すると、銀行家は、第１部第１３章[８]の説明どおり、
実業家のために、社会から実物を強制徴収（＝信用創造による物価上昇で実業家の資産価値が上がる）して、実業家が使える実物資本の流れを増やして、長期と
短期の双方のローンの利子率を下げてやるのである。要するに、銀行家の利子率が長期ローンの実質利子率に機械的に縛られるというのは事実だが、この実質利
子率が銀行家の手の届かないところで決まっているというのは事実ではないのである。」
My running comments on the above have been made in the
footnotes. The perplexity which I find in Marshall's account of the
matter is fundamentally due, I think, to the incursion of the concept
“interest”, which belongs to a monetary economy, into a treatise which
takes no account of money. “Interest” has really no business to turn up
at all in Marshall's Principles of Economics, ― it belongs to another
branch of the subject. Professor Pigou, conformably with his other
tacit assumptions, leads us (in his Economics of Welfare) to infer that
the unit of waiting is the same as the unit of current investment and
that the reward of waiting is quasi-rent, and practically never
mentions interest, ― which is as it should be. Nevertheless these
writers are not dealing with a non-monetary economy (if there is such a
thing). They quite clearly presume that money is used and that there is
a banking system. Moreover, the rate of interest scarcely plays a
larger part in Professor Pigou's Industrial Fluctuations (which is
mainly a study of fluctuations in the marginal efficiency of capital)
or in his Theory of Unemployment (which is mainly a study of what
determines changes in the volume of employment, assuming that there is
no involuntary unemployment) than in his Economics of Welfare.
上記に引用についての私の見解は注釈に含めた。利子率についてのマーシャルの記述の中で私が見出した混乱の原因は、根本的には、貨幣経済に属する「利子
率」という概念を、貨幣を扱わない書物の中に持ち込んだことにあると思われる。実際には「利子率」はマーシャルの『経済原理』の中には登場する必要はない
である。―利子率は経済のもう一つの枝に属するからである。ピグー教授は、彼自身の別の暗黙の想定に満足して、（『厚生経済学』において）待忍の単位は現
行投資の単位と同じものであり、待忍の報酬は準地代（＝資本からの所得、地代に似ているからこういう）であると我々に思わせようとして、利子率のことには
実質上一切言及していない。―しかもそれが正しいのである。にも関わらず、この二人は貨幣のない社会（もしそんな社会があればだが）を扱っているのではな
く、貨幣の使用と銀行の存在を明らかに前提にしているのである。さらに言えば、ピグー教授の『産業変動論』（主に資本の限界効率の変動の研究をしている）
でも『失業論』（主に雇用量の変化を決めるものについての研究で、非自発的失業が存在しないことを前提にしている）でも『厚生経済学』と同じくほとんど利
子率は登場しないのである（＝no more...thanの構文）。
II
The following from his Principles of Political Economy (p.511)
puts the substance of Ricardo's theory' of the Rate of Interest:
第２節
リカードの『経済学原理』（５１１頁）の次の引用の中に、リカードの利子率理論の本質が表れている。
“The interest of money is not regulated by the rate at which the Bank
will lend, whether it be 5, 3 or 2 per cent, but by the rate of profit
which can be made by the employment of capital, and which is total
independent of the quantity or of the value of money. Whether the Bank
lent one million, ten millions, or a hundred millions, they would not
permanently alter the market rate of interest; they would alter only
the value of the money which they thus issued. In one case, ten or
twenty times more money might be required to carry on the same business
than what might be required in the other. The applications to the Bank
for money, then, depend on the comparison between the rate of profits
that may he made by the employment of it, and the rate at which they
are willing to lend it. If they charge less than the market rate of
interest, there is no amount of money which they might not lend; ― if
they charge more than that rate, none but spendthrifts and prodigals
would be found to borrow of them.”
「利子を決めるのは、銀行が金を貸し出す利率（５％，３％，２％のいずれであっても）ではなく、資本の利用によって生まれる利益の比率であって、それは貨
幣量や貨幣価値とは何の関係もない。銀行が百万貸そうが、１千万貸そうが、１億貸そうが、それで市場利子率が長期的に変わるわけではない。単に自分たちの
発行した貨幣の価値が変わるだけである。同じ事業を行うのにも、ある場合（＝貨幣価値が落ちた場合）には、他の場合に必要だったのと比べて十倍か二十倍も
多くの貨幣が必要となるかもしれない。だから、銀行に対する借金の申し込みは、その金で生み出される利益率と銀行が貸し出す利子率を天秤にかけて行うこと
になる。もし銀行が市場利子率より低い利子を課すなら、銀行はどんな額でも貸出しできるだろう。しかし、もし銀行が市場利子率より高い利子を課すなら、浪
費家か道楽者しか借手は見つからないだろう。」
This is so clear-cut that it affords a better starting-point for
a discussion than the phrases of later writers who, without really
departing from the essence of the Ricardian doctrine, are nevertheless
sufficiently uncomfortable about it to seek refuge in haziness. The
above is, of course, as always with Ricardo, to be interpreted as a
long-period doctrine, with the emphasis on the word “permanently”
half-way through the passage; and it is interesting to consider the
assumptions required to validate it.
この文章は極めて明確なので、後世の学者の文章よりは議論の出発点にするのに相応しい。後世の学者たちはリカードの説の本質から決して離れることがない
のに、リカードの説に居心地の悪さを感じてうやむやにして逃げているのである。もちろんこの文章はリカードのいつもの例に漏れず、長期の理論であると解釈
すべきであって、文章の真ん中の「長期的に」を強調して読まねばならない。そして、この説が正しいと認めるために必要な前提を考えることは興味深い。
Once again the assumption required is the usual classical
assumption, that there is always full employment; so that, assuming no
change in the supply curve of labour in terms of product, there is only
one possible level of employment in long-period equilibrium. On this
assumption with the usual ceteris paribus, i.e. no change in
psychological propensities and expectations other than those arising
out of a change in the quantity of money, the Ricardian theory is
valid, in the sense that on these suppositions there is only one rate
of interest which will be compatible with full employment in the long
period. Ricardo and his successors overlook the fact that even in the
long period the volume of employment is not necessarily full but is
capable of varying, and that to every banking policy there corresponds
a different long-period level of employment; so that there are a number
of positions of long-period equilibrium corresponding to different
conceivable interest policies on the part of the monetary authority.
ここで必要とされている前提はいつもの古典派の前提、つまり「常に完全雇用であること」である。つまり、生産物で測った労働の供給曲線に変化がないと想定
するとき、長期均衡で可能な雇用水準はただ一つである。これを前提として、他の条件が同じで、心理的な性向も期待の変化も貨幣量の変化から由来するもの以
外はいかなる変化も起こらないとするなら、リカードの説は有効である。それはこの前提のもとで長期における完全雇用と両立する利子率は一つしかないという
意味である。リカードとその後継者たちは、たとえ長期でも雇用量は必ずしも完全状態ではなく変化する可能性があるし、銀行の方針が変わればそれに応じて長
期の雇用水準も様々に変化するという事実を見逃しているのである。つまり、貨幣当局の金利政策が変わればそれに対応する長期の均衡状態の位置も沢山存在す
るのである。
If Ricardo had been content to present his argument solely as
applying to any given quantity of money created by the monetary
authority, it would still have been correct on the assumption of
flexible money-wages. If, that is to say, Ricardo had argued that it
would make no permanent alteration to the rate of interest whether the
quantity of money was fixed by the monetary authority at ten millions
or at a hundred millions, his conclusion would hold. But if by the
policy of the monetary authority we mean the terms on which it will
increase or decrease the quantity of money. i.e. the rate of interest
at which it will, either by a change in the volume of discounts or by
open-market operations, increase or decrease its assets ― which is what
Ricardo expressly does mean in the above quotation ― then it is not the
case either that the policy of the monetary authority is nugatory or
that only one policy is compatible with long-period equilibrium; though
in the extreme case where money-wages are assumed to fall without limit
in face of involuntary unemployment through a futile competition for
employment between the unemployed labourers, there will, it is true, be
only two possible long-period positions ― full employment and the level
of employment corresponding to the rate of interest at which
liquidity-preference becomes absolute (in the event of this being less
than full employment.). Assuming flexible money-wages, the quantity of
money as such is, indeed, nugatory in the long period; but the terms on
which the monetary authority will change the quantity of money enters
as a real determinant into the economic scheme.
もしリカードが自分の理論は貨幣当局が創造した一定の貨幣量に対してのみ当てはまるものであることで満足なら、貨幣賃金が変化する想定でも彼の理論は有効
だろう。つまり、もしリカードが、貨幣量が貨幣当局によって固定されている場合には、それが１千万だろうが１億だろうが、利子率は長期的に変化がないと言
うなら、彼の結論は有効である。しかし、貨幣当局の方針が、貨幣量を増減させるための条件、即ち当局が割引額の変更や公開市場操作によってその資産を増減
させる利子率を意味するなら（これは上記の引用でリカードがまさに強調している点である）、貨幣当局の政策は無効ではないし、長期の均衡と両立する政策
（＝利子率）は一つしかないわけでもない。ただし、失業労働者間の雇用をめぐる些細な競争のせいで非自発的失業が発生して、貨幣賃金が無制限に下ると思わ
れる極端なケースでは、確かに長期の均衡位置は二つだけになる。それは、一つは完全雇用であるが、もう一つは流動性選好が絶対的になったとき（この場合は
完全雇用に達していない）の利子率に対応する雇用水準である。貨幣賃金が変化する想定では、貨幣量はそれだけでは長期的には効果がない。そうではなく、貨
幣当局が貨幣量を変更する条件（＝利子率）こそが真の決定要因として経済スキームの中に入ってくるのである。
It is worth adding that the concluding sentences of the
quotation suggest that Ricardo was overlooking the possible changes in
the marginal efficiency of capital according to the amount invested.
But this again can be interpreted as another example of his greater
internal consistency compared with his successors. For if the quantity
of employment and the psychological propensities of the community are
taken as given, there is in fact only one possible rate of accumulation
of capital and, consequently, only one possible value for the marginal
efficiency of capital. Ricardo offers us the supreme intellectual
achievement, unattainable by weaker spirits, of adopting a hypothetical
world remote from experience as though it were the world of experience
and then living in it consistently. With most of his successors common
sense cannot help breaking in ― with injury to their logical
consistency.
もうひとつ付け加えると、引用文の結論部分でリカードは投資量に応じた資本の限界効率の変化の可能性を見逃している。しかし、この事実はリカードが彼の後
継者と比べて内的一貫性を維持していたことの例として見ることが出来る。というのは、もし雇用量と社会の心理傾向を所与とするなら、可能な資本の蓄積量は
ただ一つであり、その結果として、可能な資本の限界効率もただ一つだからである。リカードは経験から離れた仮想的世界をまるで経験世界であるかのよう取り
上げて、そこで首尾一貫して生き抜くという、軟弱な精神では到底達成できない最高に知的な偉業を我々に残したのである。彼の後継者たちの場合はどうしても
常識が割り込んできて、論理的な一貫性が損なわれることになるのである。
III
A peculiar theory of the rate of interest has been propounded by
Professor von Mises and adopted from him by Professor Hayek and also, I
think, by Professor Robbins; namely, that changes in the rate of
interest can be identified with changes in the relative price levels of
consumption-goods and capital-goods.[9] It is not clear how this
conclusion is reached. But the argument seems to run as follows. By a
somewhat drastic simplification the marginal efficiency of capital is
taken as measured by the ratio of the supply price of new consumers'
goods to the supply price of new producers' goods.[10] This is then
identified with the rate of interest. The fact is called to notice that
a fall in the rate of interest is favourable to investment. Ergo, a
fall in the ratio of the price of consumers' goods to the price of
producers' goods is favourable to investment.
第３節
奇抜な利子率論を展開したのはフォン・ミーゼス教授で、その理論はハイエク教授とロビン教授に採用されている。その理論とは、利子率の変化は、消費財と資
本財の相対的価格水準の変化と一致するとするものである[９]。どうしてこんな結論になったのかは明らかではない。議論は次のように進む。いくらか斬新な
単純化によって、資本の限界効率は新たな消費財の供給価格と新たな生産財の供給価格の比率によって測ることが出来る[１０]。すると、これは利子率と一致
する。この事実は、利子率の下落が投資に有利であることを教えている。したがって、消費財の価格と生産財の価格の比率の低下は投資に有利である。
By this means a link is established between increased saving by
an individual and increased aggregate investment. For it is common
ground that increased individual saving will cause a fall in the price
of consumers' goods, and, quite possibly, a greater fall than in the
price of producers' goods, hence, according to the above reasoning, it
means a reduction in the rate of interest which will stimulate
investment. But, of course, a lowering of the marginal efficiency of
particular capital assets, and hence a lowering of the schedule of the
marginal efficiency of capital in general, has exactly the opposite
effect to what the argument assumes. For investment is stimulated
either by a raising of the schedule of the marginal efficiency or by a
lowering of the rate of interest. As a result of confusing the marginal
efficiency of capital with the rate of interest, Professor von Mises
and his disciples have got their conclusions exactly the wrong way
round.
この手段によって個人の貯蓄の増加と総投資の増加の間に結びつきが生まれる。というのは、個人の貯蓄の増加は消費財の価格の低下を引き起こし、さらに生産
財の価格のさらに大きな低下を引き起こす可能性が極めて高く、それは上記の理屈では利子率の低下を意味し投資を刺激する。しかし、当然、特定の資本資産の
限界効率が低下して、一般に資本の限界効率表が下がることは、この理論の想定とは正反対の降下を持っている。というのは、
投資は資本の限界効率表を引き上げるか利子率が低下することで刺激されるからである。資本の限界効率と利子率のを混同した結果、ミーゼス教授と彼の弟子たちは結論で間違った方向に進んでしまったのである。
A good example of a confusion along these lines is given by the
following passage by Professor Alvin Hansen: [11] “It has been
suggested by some economists that the net effect of reduced spending
will be a lower price level of consumers' goods than would otherwise
have been the case, and that, in consequence, the stimulus to
investment in fixed capital would thereby tend to be minimized. This
view is, however, incorrect and is based on a confusion of the effect
on capital formation of (1) higher or lower prices of consumers' goods,
and (2) a change in the rate of interest. It is true that in
consequence of the decreased spending and increased saving, consumers'
prices would be low relative to the prices of producers' goods. But
this, in effect, means a lower rate of interest, and a lower rate of
interest stimulates an expansion of capital investment in fields which
at higher rates would be unprofitable.”
この混乱の明らかな例は、アルヴィン・ハンセン教授の次の文章に表れている[１１]。「経済学者の中には、支出の減少の効果は、そうでない場合よりも消費
財の価格水準が大きく低下することであり、その結果、固定資本の投資に対する刺激が小さくなってしまうと考える人がいるが、この考え方は間違っている。消
費財の価格の上昇（１）と下降の資本形成に対する影響と、利子率の変化（２）の影響を混同しているのである。支出の減少と貯蓄の増加の結果として、消費者
物価は生産財価格と比べて低下するのは事実であるが、これは実際には利子率の低下を意味しており、利子率の低下は高い利子率では不利な分野への資本投資の
拡大を引き起こすのである。」
Author's Footnotes
[1]. It is to be noticed that Marshall uses the word “capital” not
“money” and the word “stock” not “loans”; interest is a payment for
borrowing money, and “demand for capital” in this context should mean
“demand for loans of money for the purpose of buying a stock of
capital-goods”. But the equality between the stock of capital-goods
offered and the stock demanded will be brought about by the prices of
capital-goods, not by the rate of interest. It is equality between the
demand and supply of loans of money, i.e. of debts, which is brought
about by the rate of interest.
[2]. This assumes that income is not constant. But it is not obvious in
what way a rise in the rate of interest will lead to “extra work”. Is
the suggestion that a rise in the rate of interest is to be regarded,
by reason of its increasing the attractiveness of working in order to
save, as constituting a sort of increase in real wages which will
induce the factors of production to work for a lower wage? This is, I
think, in Mr. D. H. Robertson's mind in a similar context. Certainly
this “would not quickly amount to much”; and an attempt to explain the
actual fluctuations in the amount of investment by means of this factor
would be most unplausible, indeed absurd. My rewriting of the latter
half of this sentence would be: “and if an extensive increase in the
demand for capital in general, due to an increase in the schedule of
the marginal efficiency of capital, is not offset by a rise in the rate
of interest, the extra employment and the higher level of income, which
will ensue as a result of the increased production of capital-goods,
will lead to an amount of extra waiting which in terms of money will be
exactly equal to the value of the current increment of capital-goods
and will, therefore, precisely provide for it.”
[3]. Why not by a rise in the supply price of capital-goods? Suppose,
for example, that the “extensive increase in the demand for capital in
general” is due to a fall in the rate of interest. I would suggest that
the sentence should be rewritten: “In so far, therefore, as the
extensive increase in the demand for capital-goods cannot be
immediately met by an increase in the total stock, it will have to be
held in check for the time being by a rise in the supply price of
capital-goods sufficient to keep the marginal efficiency of capital in
equilibrium with the rate of interest without there being any material
change in the scale of investment; meanwhile (as always) the factors of
production adapted for the output of capital-goods will be used in
producing those capital-goods of which the marginal efficiency is
greatest in the new conditions.”
[4]. In fact we cannot speak of it at all. We can only properly speak
of the rate of interest on money borrowed for the purpose of purchasing
investments of capital, new or old (or for any other purpose).
[5]. Here the wording is ambiguous as to whether we are to infer that
the postponement of consumption necessarily has this effect, or whether
it merely releases resources which are then either unemployed or used
for investment according to circumstances.
[6]. Not, be it noted, the amount of money which the recipient of
income might, but does not, spend on consumption; so that the reward of
waiting is not interest but quasi-rent. This sentence seems to imply
that the released resources are necessarily used. For what is the
reward of waiting if the released sources are left unemployed?
[7]. We are not told in this passage whether net savings would or would
not be equal to the increment of capital, if we were to ignore
misdirected investment but were to take account of “temporary
accumulations of unused claims upon services in the form of
bank-money”. But in Industrial Fluctuations (p. 22) Prof. Pigou makes
it clear that such accumulations have no effect on what he calls “real
savings”.
[8]. This reference (op. cit. pp. 129-134) contains Prof. Pigou's view
as to the amount by which a new credit creation by the banks increases
the stream of real capital available for entrepreneurs. In effect he
attempts to deduct “from the floating credit handed over to business
men through credit creations the floating capital which would have been
contributed in other ways if the banks had not been there”. After these
deductions have been made, the argument is one of deep obscurity. To
begin with, the rentiers have an income of 1500, of which they consume
500 and save 1000; the act of credit creation reduces their income to
1300, of which they consume 500 - x and save 800 + x; and x, Prof.
Pigou concludes, represents the net increase of capital made available
by the act of credit creation. Is the entrepreneurs' income supposed to
be swollen by the amount which they borrow from the banks (after making
the above deductions)? Or is it swollen by the amount, i.e. 200, by
which the rentiers' income is reduced? In either case, are they
supposed to save the whole of it? Is the increased investment equal to
the credit creations minus the deductions? Or is it equal to x? The
argument seems to stop just where it should begin.
[9]. The Theory of Money and Credit, p. 339 et passim, particularly p. 363.
[10]. If we are in long-period equilibrium, special assumptions might
be devised on which this could be justified. But when the prices in
question are the prices prevailing in slump conditions, the
simplification of supposing that the entrepreneur will, in forming his
expectations, assume these prices to be permanent, is certain to be
misleading. Moreover, if he does, the prices of the existing stock of
producers' goods will fall in the same proportion as the prices of
consumers' goods.
[11]. Economic Reconstruction, p. 233.
著者注
[１] 注意すべきことは、マーシャルはここで「貨幣」の代わりに「資本」という言葉を使い、「融資」の代わりに「ストック」という言葉を使っていること
である（＝この文章は前の単語に置き換えて読め）。利子は貨幣を借りたことに対する対価であり、この文脈での「資本需要」とは「資本財ストックを購入する
目的で貨幣を融資する需要」を意味する。しかし、資本財ストックの供給と需要の一致は、利子率ではなく資本財の価格によってもたらされる。利子率によって
もたらされるのは、貨幣融資（つまり債権）の需要と供給の一致なのである。
[２] これは所得を一定と想定していないことになる。しかし、利子率の上昇がどうやって「労働の増加」になるのか明らかでない。この意味は、利子率が上
昇すると、貯蓄のために働く魅力が増えることで、実質賃金が上昇するのと同じ効果を持つと見做せるので、生産要素はもっと低い賃金で働く気になるというこ
とだろうか？ これが同じ文脈でD.H.ロバートソン氏の考えであると思われる。確かに、労働の増加は「急に大きな量になることはない」。確かに、この要
素によって実際の投資量の変化を説明するのは非現実的であるどころか馬鹿げている。この文章の後半を私が書き直すと、「そしてもし資本の限界効率表の上昇
に起因する一般的な資本需要の大幅な増加が利子率の上昇によって相殺されなかったら、資本財の生産増加の結果として発生する雇用の増加と所得水準の上昇が
待忍の増加をもたらす。この待忍の増加は貨幣で測ると資本財の当期の増加と丁度一致する。つまり、待忍の増加がまさに資本財の増加をもたらすのである。」
[３] なぜ資本財の供給の増加ではないのか？ 例えば、仮に「一般的な資本需要の大幅な増加」が利子率の下落によって起こるとするなら、この文章は次の
ように書き直すのがよいと思う。「したがって、資本需要の大幅な増加が総ストックの増加によって直ちに満たされない場合には、資本需要の増加は当面は資本
財の供給価格の増加によって食い止めるしかないだろう。そうして投資規模の実質的な変化が起きないままで、資本の限界効率と利子率の均衡を保つのである。
その間に（いつものように）資本財の産出に適合した生産要素が、限界効率が新たな条件下で最大となるような資本財を生産するために使われるのである。」
[４] 実際には我々はこんな言い方は決してしない。利子率は借りた貨幣についてのみ正しく言うことが出来るもので、その目的が資本の投資物件の購入であれ何であれ構わないし、投資物件が新しくても古くてもよいのである。
[５] 消費の延期は必然的にこの効果を持つと推定すべきなのか、それとも、消費の延期は利用されない資源を単に状況に応じて投資に解放するということなのか、この言葉遣いでは明確ではない。
[６] これは所得の受領者が消費に使えるが使わない貨幣の量でないことに注意。だから、待忍の報酬は利子ではなく準地代であるとなっている。この文章の
意味は、解放された資源は必然的に使用されるかのようである。というのは、もし解放された資源が利用されずに放置されたら、待忍の報酬はどこからも来ない
からである。
[７]
もし誤用された投資を無視して「未使用の用役に対する権利を銀行貨幣の形で一時的に蓄えたもの」を考慮に入れたら、純貯蓄は資本の増加に等しくなるのかど
うかはこの文章からは分からない。しかし、『産業変動論』（２２頁）ではピグー教授は、そのように蓄えたものは「実質貯蓄」と彼が呼ぶものには何の影響も
与えないと言っている。
[８] この参照箇所（前掲書１２９～１３４頁）には、銀行家による新たな信用創造によって企業家にとって利用可能となる実物資本の流れがどれだけ増える
かについて、ピグー教授が見解を述べている。要するに、教授は「信用創造によって実業家に渡される一時的信用から、銀行がなくても他の方法で供給されたは
ずの一時的資本」を差し引こうとするのである。この控除の後の議論がよくわからない。まず、利子生活者は１５００の所得を得る。そのうち５００を消費して
１０００を貯蓄する。信用創造行為は彼らの所得を１３００に減らす（＝２００が強制徴収、インフレによる損失）。そのうち５００－ｘを消費し８００＋ｘを
貯蓄する。ピグー教授が言うには、このｘが信用創造行為によって利用可能となった資本の純増加分である。では、企業家の所得は銀行からの借金によって増え
るというのだろうか。それとも、利子生活者の所得が減った２００だけ企業家の所得は（上記の控除後でも）増えるのだろうか。どちらにしても、利子生活者は
その全額を貯蓄するというのだろうか。投資の増加は信用創造から控除を引いた分に等しいのだろうか。あるいは、投資の増加はｘと等しいのだろうか。議論は
まさに始まるところで終わっているのである。
[９] 『貨幣と信用の理論』３３９頁以下、特に３６９頁。
[１０] もし長期の均衡状態にあるなら、資本の限界効率をこのように測定する方法を正当化するために特別な想定を工夫することは出来る。しかし、この二
つの供給価格が不況時の市場価格である時、企業家は予想を立てる際にこの値段を長期的なものと考えると単純に想定するのは、明らかに間違いである。その
上、もし企業家がそう考えるなら、生産財の現存ストックの価格は消費財の価格と同じ割合で下落してしまうだろう。
[１１] 「経済再建』２３３頁
Chapter 15. The Psychological and Business Incentives To Liquidity
第１５章 流動性に対する心理的と経営的誘引
I
WE must now develop in more detail the analysis of the motives
to liquidity-preference which were introduced in a preliminary way in
Chapter 13. The subject is substantially the same as that which has
been sometimes discussed under the heading of the Demand for
Money（貨幣需要）. It is also closely connected with what is called the
income-velocity（流通速度） of money; ― for the income-velocity of money
merely measures what proportion of their incomes the public chooses to
hold in cash, so that an increased income-velocity of money may be a
symptom of a decreased liquidity-preference. It is not the same thing,
however, since it is in respect of his stock of accumulated savings,
rather than of his income, that the individual can exercise his choice
between liquidity and illiquidity. And, anyhow, the term
“income-velocity of money” carries with it the misleading suggestion of
a presumption in favour of the demand for money as a whole being
proportional, or having some determinate relation, to income, whereas
this presumption should apply, as we shall see, only to a portion of
the public's cash holdings; with the result that it overlooks the part
played by the rate of interest.
第１節
いまや我々は第１３章で予備的に導入した流動性選好の動機の分析をさらに詳細に発展させる時である。このテーマは貨幣需要という見出しのもとで議論されて
きたものと本質的には同じである。また貨幣の所得速度と呼ばれているものと密接に結びついている。―
というのは貨幣の所得速度は、単に社会が所得のどの割合を現金で保有しようとしているかを表しているが、貨幣の所得速度が上がることは流動性選好が減少す
ることの表すからである。しかしながら、両者は同じものではない。なぜなら、個人が流動性（＝現金）と非流動性（＝債権）のどちらを選ぶかは、所得との関
係ではなく、自分の貯蓄ストックとの関係で選ぶからである。さらに、とにかく「貨幣の所得速度」という言い方は、貨幣需要が全体として所得に比例している
か、あるいは貨幣需要が所得と明確な関係にあると誤解されやすい。実際にはこの表現は、これから見るように、社会の現金保有の一部についてのみ当てはまる
だけである。その結果、貨幣需要に対して利子率の果たす役割を見逃していることになる。
In my Treatise on Money I studied the total demand for money
under the headings of income-deposits, business-deposits, and
savings-deposits, and I need not repeat here the analysis which I gave
in Chapter 3 of that book. Money held for each of the three purposes
forms, nevertheless, a single pool, which the holder is under no
necessity to segregate into three water-tight compartments; for they
need not be sharply divided even in his own mind, and the same sum can
be held primarily for one purpose and secondarily for another. Thus we
can ― equally well, and, perhaps, better ― consider the individual's
aggregate demand for money in given circumstances as a single decision,
though the composite result of a number of different motives.
自著『貨幣論』で私は貨幣需要の全体について、所得預金、営業預金、貯蓄預金という項目に分けて研究した。その本の第３章で行った分析をここで繰り返す必
要はない。ただし、この三つの目的のそれぞれのために保有された貨幣は一つのプールを形成しており、保有者はこの三つの区切りを厳密に区別する必要はまっ
たくないのである。この三つの目的は人々の頭の中ではっきり分かれている必要もない。同じ金額の保有が主に一つ目の目的で副次的にもう一つの目的であって
も構わない。つまり、元々は別の動機から来ているとしても、所与の環境における個人の貨幣需要の全体を一つの決断と見なすことが出来るし、その方がうまく
いくのである。
In analysing the motives, however, it is still convenient to
classify them under certain headings, the first of which broadly
corresponds to the former classification of income-deposits and
business-deposits, and the two latter to that of savings-deposits.
These I have briefly introduced in Chapter 13 under the headings of the
transactions-motive, which can be further classified as the
income-motive and the business-motive, the precautionary-motive and the
speculative-motive.
しかし、動機を分析する場合には、やはりしかるべき項目に分類する方が便利である。その一つめは、以前の分類の所得預金と営業預金に対応するもので、あ
との二つは貯蓄預金に相当する。これらは第十三章で簡単に触れておいたもので、取引動機（ここでは所得動機と営業動機に相当する）と予備的動機と投機的動
機である。
(i) The Income-motive. ― One reason for holding cash is to bridge the
interval between the receipt of income and its disbursement. The
strength of this motive in inducing a decision to hold a given
aggregate of cash will chiefly depend on the amount of income and the
normal length of the interval between its receipt and its disbursement.
It is in this connection that the concept of the income-velocity of
money is strictly appropriate.
（一）所得動機―現金保有の一つの理由は、所得の受取と支出の間を橋渡しをすることである。一定の現金全部を保有する気になるこの動機の強さは、主に所得
量および所得の受取と支出の通常の間隔に依存する。これとの関連では、まさに貨幣の所得速度という概念が厳密に当てはまる。
(ii) The Business-motive. ― Similarly, cash is held to bridge the
interval between the time of incurring business costs and that of the
receipt of the sale-proceeds; cash held by dealers to bridge the
interval between purchase and realization being included under this
heading. The strength of this demand will chiefly depend on the value
of current output (and hence on current income), and on the number of
hands through which output passes.
（二）営業動機―同様に、現金保有は営業経費の支払時期と販売売上の受取時期の間を橋渡しをする。商売人は仕入れと販売の橋渡しをするために現金を保有す
るが、これもこの項目に含まれる。この需要の強さは、主に当期の産出物の価格（したがって現行の所得）とその産出物が通過する人手の数に依存する。
(iii) The Precautionary-motive. ― To provide for contingencies
requiring sudden expenditure and for unforeseen opportunities of
advantageous purchases, and also to hold an asset of which the value is
fixed in terms of money to meet a subsequent liability fixed in terms
of money, are further motives for holding cash.
（三）予備的動機―急な出費を要する不慮の事態と、有利な買い物をする予期せぬ機会に備えること、および、貨幣で測った債務（＝保険や年金など）を果たすために貨幣価値が固定した資産（＝預金）を持つことも、現金を持つ動機である。
The strength of all these three types of motive will partly depend on
the cheapness and the reliability of methods of obtaining cash, when it
is required, by some form of temporary borrowing, in particular by
overdraft（当座貸越） or its equivalent. For there is no necessity to hold
idle cash to bridge over intervals if it can be obtained without
difficulty at the moment when it is actually required. Their strength
will also depend on what we may term the relative cost of holding cash.
If the cash can only be retained by forgoing the purchase of a
profitable asset, this increases the cost and thus weakens the motive
towards holding a given amount of cash. If deposit interest is earned
or if bank charges are avoided by holding cash, this decreases the cost
and strengthens the motive. It may be, however, that this is likely to
be a minor factor except where large changes in the cost of holding
cash are in question.
この三つのタイプの動機の強さは、必要な時に現金を手に入れる手段、つまり何らかの一時的借り入れ、特に当座貸越のような手段が安価で信頼性のあることに
依存している。というのは、現金が必要な時に難なく手に入るなら、間隔を埋めるために無駄な現金を手元に置く必要はないからである。またこの三つの動機の
強さは、現金保有の相対的コスト（＝機会費用）とでも呼べるものに依存する。つまり、もし有利な資産の買い入れをやめることでしか現金が保持できないな
ら、現金保持のコスト（＝機会費用）が増えるので、一定量の現金を保有する動機は弱くなる。もし預金金利が稼げるかあるいは現金保有によって銀行の手数料
を回避できるなら、現金保有のコストは下がるので動機は強まる。しかしながら、現金保有のコストの大きな変化が問題となる場合を除いては、このコストは小
さい要因であると言っていい。
(iv) There remains the Speculative-motive. ― This needs a more detailed
examination than the others, both because it is less well understood
and because it is particularly important in transmitting the effects of
a change in the quantity of money.
（四）最後に投機的動機―これについては他の動機より詳細な検討が必要である。というのは、この動機はあまりよく理解されていないし、貨幣量の変化の影響を伝えるのに特に大切だからである。
In normal circumstances the amount of money required to satisfy
the transactions-motive and the precautionary-motive is mainly a
resultant of the general activity of the economic system and of the
level of money-income. But it is by playing on the speculative-motive
that monetary management (or, in the absence of management, chance
changes in the quantity of money) is brought to bear on the economic
system. For the demand for money to satisfy the former motives is
generally irresponsive to any influence except the actual occurrence of
a change in the general economic activity and the level of incomes;
whereas experience indicates that the aggregate demand for money to
satisfy the speculative-motive usually shows a continuous response to
gradual changes in the rate of interest, i.e. there is a continuous
curve relating changes in the demand for money to satisfy the
speculative motive and changes in the rate of interest as given by
changes in the prices of bonds and debts of various maturities.
普通の状況では、取引動機と予備的動機を満たすための貨幣需要は、おもに一般的な経済活動の結果として、また貨幣による所得水準の結果として発生する。し
かし、貨幣政策（政策がない場合には貨幣量の偶然の変化）の経済に対する働きかけは、投機的動機に対する働きかけとして行われる。というのは、取引動機と
予備的動機を満たすための貨幣需要が影響を受けるのは、一般的な経済活動と所得水準の現実の変化だけで、一般的にそれ以外から影響を受けることはない。一
方、経験が教えるところでは、投機的動機を満たすための総貨幣需要はふつう利子率の段階的な変化に連続的に影響を受ける。つまり、投機的動機を満たすため
の貨幣需要の変化と、様々な満期の債券価格の変化に表れる利子率の変化を結びつける連続的な曲線が存在するのである。
Indeed, if this were not so, “open market operations” would be
impracticable. I have said that experience indicates the continuous
relationship stated above, because in normal circumstances the banking
system is in fact always able to purchase (or sell) bonds in exchange
for cash by bidding the price of bonds up (or down) in the market by a
modest amount; and the larger the quantity of cash which they seek to
create (or cancel)（貨幣創造とその逆） by purchasing (or selling) bonds and
debts, the greater must be the fall (or rise) in the rate of interest.
Where, however, (as in the United States, 1933-1934) open-market
operations have been limited to the purchase of very short-dated
securities, the effect may, of course, be mainly confined to the very
short-term rate of interest and have but little reaction on the much
more important long-term rates of interest.
実際、もしそうでなかったら「公開市場操作」などは実行不可能である。私が言ったように、経験が教えるところでは貨幣需要と利子率の間には連続的関係が存
在する。なぜなら、普通の状況では、銀行は常に市場で債券価格をせり上げ（下げ）て現金と交換に債券を適度に購入（売払）することが出来るからである。そ
して、銀行が債券と債権を買う（売る）ことで創造（回収）しようとする現金の量が多ければ多いほど、利子率の下降（上昇）は大きくなる。しかしながら、
（１９３３年から１９３４年の合衆国のように）公開市場操作が非常に単期日の証券の購入に限られている場合には、もちろん、その効果は非常に短期の利子率
に限定されるし、もっと重要な長期の利子率に対してはたいした作用を与えない。
In dealing with the speculative-motive it is, however, important
to distinguish between the changes in the rate of interest which are
due to changes in the supply of money available to satisfy the
speculative-motive, without there having been any change in the
liquidity function, and those which are primarily due to changes in
expectation affecting the liquidity function itself. Open-market
operations may, indeed, influence the rate of interest through both
channels; since they may not only change the volume of money, but may
also give rise to changed expectations concerning the future policy of
the Central Bank or of the Government. Changes in the liquidity
function itself, due to a change in the news（情勢の変化） which causes
revision of expectations, will often be discontinuous, and will,
therefore, give rise to a corresponding discontinuity of change in the
rate of interest. Only, indeed, in so far as the change in the news is
differently interpreted by different individuals or affects individual
interests differently will there be room for any increased activity of
dealing in the bond market. If the change in the news affects the
judgment and the requirements of everyone in precisely the same way,
the rate of interest (as indicated by the prices of bonds and debts)
will be adjusted forthwith to the new situation without any market
transactions being necessary.
しかしながら、投機的動機を扱うにあたって重要なのは、利子率の変化のうちでも、流動性関数が不変な状態で投機的動機を満たすために利用可能な「貨幣供給
の変化から来る利子率の変化」と、流動性関数そのものに影響を与える「予想の変化から来る利子率の変化」とを区別することである。確かに、公開市場操作は
この二つのルートから利子率に影響を与える。というのは、公開市場操作は貨幣量を変えるだけではなく、中央銀行や政府の将来の方針についての予想にも変化
をもたらすからである。＜しかし、＞予想の変化は情勢の変化によってもたらされ、情勢の変化が流動性関数の変化をもたらすが、その変化はしばしば非連続で
あり、したがって、それに対応する利子率の変化も非連続なのである。実際、情勢の変化が人によって異なって解釈をされ、人々の利害に与える影響も異なって
いる場合のみ、債券市場の取引活動が増える可能性があるのだ。もし情勢の変化が全員の判断と要求とに全く同じように影響するなら、利子率（債券と債権に表
れる）は市場取引を全く必要とせずに即座に新たな状況に適応するだろう。
Thus, in the simplest case, where everyone is similar and
similarly placed, a change in circumstances or expectations will not be
capable of causing any displacement of money whatever; ― it will simply
change the rate of interest in whatever degree is necessary to offset
the desire of each individual, felt at the previous rate, to change his
holding of cash in response to the new circumstances or expectations;
and, since everyone will change his ideas as to the rate which would
induce him to alter his holdings of cash in the same degree, no
transactions will result. To each set of circumstances and expectations
there will correspond an appropriate rate of interest, and there will
never be any question of anyone changing his usual holdings of cash.
つまり、全員が似ていて似たような立場であるという最も単純なケースでは、環境の変化や予想の変化は貨幣の移動を全く引き起こすことはなく、単に利子率
の変化をもたらすだけである。そして、その変化によって、元の利子率の時に新しい環境や予想に対応して現金保有量を変えたいと感じた気持ちは消えてしまう
のである。そして、前なら現金保有量を変えたくなった利子率についての全員の考えも一斉に変わってしまうので、どんな取引も発生しないのである。それぞれ
の環境と予想に対して適当な利子率が対応するなら、人は誰も自分のいつもの現金保有量を変えようとはしないのである。
In general, however, a change in circumstances or expectations
will cause some realignment in individual holdings of money; ― since,
in fact, a change will influence the ideas of different individuals
differently by reason partly of differences in environment and the
reason for which money is held and partly of differences in knowledge
and interpretation of the new situation. Thus the new equilibrium rate
of interest will be associated with a redistribution of money-holdings.
Nevertheless it is the change in the rate of interest, rather than the
redistribution of cash, which deserves our main attention. The latter
is incidental to individual differences, whereas the essential
phenomenon is that which occurs in the simplest case. Moreover, even in
the general case, the shift in the rate of interest is usually the most
prominent part of the reaction to a change in the news. The movement in
bond-prices is, as the newspapers are accustomed to say, “out of all
proportion to the activity of dealing”; ― which is as it should be, in
view of individuals being much more similar than they are dissimilar in
their reaction to news.
しかしながら、一般的には、環境の変化や予想の変化は個人の貨幣保有量をいくらか調整させる。―なぜなら、実際、変化は様々な人達の考え方に様々に影響す
るからである。ある場合には、環境の違いと貨幣を保有する理由の違いによって、またある場合には、新たな状況に対する知識と解釈の違いによって異なってく
る。つまり、新たな利子率の均衡は貨幣保有の再分配を伴うのである。それにもかからず、我々が注目すべきは現金の再分配ではなく利子率の変化なのである。
現金の再分配は個人の相違に付随するものであって、主な現象はもっとも単純なケースでも発生する利子率の変化なのである。さらに、一般的な場合において
も、利子率の変化は情勢の変化に対する反応のうちでも通常もっとも目立ったものである。債券価格の動きは、新聞がよく言うように、「取引活動とは不釣合
い」に大きなものである。しかし、新たな情勢に対する個々人の反応は多くの場合よく似たものであるとことを考えれば、それはそうならざるをえないのである
（＝同じ方向に一斉に動くから）。
II
Whilst the amount of cash which an individual decides to hold to
satisfy the transactions-motive and the precautionary-motive is not
entirely independent of what he is holding to satisfy the
speculative-motive, it is a safe first approximation to regard the
amounts of these two sets of cash-holdings as being largely independent
of one another. Let us, therefore, for the purposes of our further
analysis, break up our problem in this way.
第２節
個人が取引動機と予備的動機を満たすために保有しようと決める現金の量は、投機的動機を満たすために保有している貨幣の量とまったく無関係ではないが、こ
れらの両者の貨幣保有量は互いにほとんど無関係であると言ってよいだろう。したがって、分析を進めるにあたって我々は問題を次のように分割しよう。
Let the amount of cash held to satisfy the transactions- and
precautionary-motives be M1, and the amount held to satisfy the
speculative-motive be M2. Corresponding to these two compartments of
cash, we then have two liquidity functions L1 and L2. L1 mainly depends
on the level of income, whilst L2 mainly depends on the relation
between the current rate of interest and the state of expectation. Thus
つまり、取引動機と予備的動機を満たすための貨幣保有量をＭ１とし、投機的動機と満たすための貨幣保有量をＭ２とするのである。そして、この二つの現金の
区分に対応する二つの流動性関数をＬ１とＬ２とする。Ｌ１は主に所得水準に依存し、Ｌ２は現行利子率と予想状況との関係に主に依存する。すると、
M = M1 + M2 = L1(Y) + L2(r) ,
where L1 is the liquidity function corresponding to an income Y, which
determines M1, and L2 is the liquidity function of the rate of interest
r, which determines M2. It follows that there are three matters to
investigate: (i) the relation of changes in M to Y and r, (ii) what
determines the shape of L1, (iii) what determines the shape of L2.
Ｍ＝Ｍ１＋Ｍ２＝Ｌ１（Ｙ）＋Ｌ２（ｒ）となる。
ここで、Ｌ１は所得Ｙに対応する流動性関数でありＭ１を決定する。Ｌ２は利子率ｒの流動性関数でありＭ２を決定する。そうすると調べるべきものが三つあって。（一）Ｍの変化がＹとｒにどう関係するか。（二）Ｌ１の形を決定するものは何か。（三）Ｌ２を決定するものは何か。
(i) The relation of changes in M to Y and r depends, in the first
instance, on the way in which changes in M come about. Suppose that M
consists of gold coins and that changes in M can only result from
increased returns（収穫、報酬） to the activities of gold-miners who belong to
the economic system under examination. In this case changes in M are,
in the first instance, directly associated with changes in Y, since the
new gold accrues as someone's income. Exactly the same conditions hold
if changes in M are due to the Government printing money wherewith to
meet its current expenditure; ― in this case also the new money accrues
as someone's income. The new level of income, however, will not
continue sufficiently high（程度） for the requirements of M1 to absorb the
whole of the increase in M; and some portion of the money will seek an
outlet in buying securities or other assets until r has fallen so as to
bring about an increase in the magnitude of M2 and at the same time to
stimulate a rise in Y to such an extent that the new money is absorbed
either in M2 or in the M1 which corresponds to the rise in Y caused by
the fall in r. Thus at one remove this case comes to the same thing as
the alternative case, where the new money can only be issued in the
first instance by a relaxation of the conditions of credit by the
banking system, so as to induce someone to sell the banks a debt or a
bond in exchange for the new cash.
（一）Ｍの変化がＹとｒにどう関係するかは、まず第一に、Ｍの変化の起こり方に依存する。Ｍは金貨からなり立ち、Ｍの変化は検討対象である経済に属する金
鉱の鉱夫たちの活動報酬の増加から来るとしよう。―このケースでは、まず、新たな金は誰かの所得として発生するから、Ｍの変化はＹの変化と直接つながって
いる。これとまったく同じ状況が当てはまるのが、政府が支出を埋めるために紙幣を印刷することでＭの変化が起こる場合である。―このケースでも新たな貨幣
は誰かの所得として発生する。しかしながら、新たな所得水準の範囲は、Ｍ１の容量がＭの増加分を全て吸収できるような範囲に留まっていることはない。貨幣
のある部分は証券や他の資産の購入に捌け口を求めるようになり、ついにはｒが下落して、その結果、Ｍ２の量が増えて、同時にＹの上昇が促される。その結果
生まれた新たな貨幣はＭ２に吸収されるか、ｒの下落によって起きたＹの上昇に対応するＭ１に吸収される。つまり、このケースはもう一つのケース（＝公開市
場操作）、即ち、人々が銀行に債券を新たな現金と交換に売る気になるように、銀行が信用条件を緩める（＝債権に高値をつける）ことで初めて新たな貨幣が発
生するケースと殆ど同じことになるのである。
It will, therefore, be safe for us to take the latter case as
typical. A change in M can be assumed to operate by changing r, and a
change in r will lead to a new equilibrium partly by changing M2 and
partly by changing Y and therefore M1. The division of the increment of
cash between M1 and M2 in the new position of equilibrium will depend
on the responses of investment to a reduction in the rate of interest
and of income to an increase in investment.[1] Since Y partly depends
on r, it follows that a given change in M has to cause a sufficient
change in r for the resultant changes in M1 and M2 respectively to add
up to the given change in M.
したがって、この二番目のケースを典型と見て間違いはないだろう。Ｍの変化はｒを変化させ、ｒの変化は一方でＭ２を変化させ一方でＹをついでＭ１を変化さ
せて新たな均衡に至るのである。新たな均衡において現金の増加分がＭ１とＭ２にどう分割されるかは、利子率の低下に投資がどう反応するか、投資の増加に所
得がどう反応するかによって決まる[１]。Ｍの変化はｒの変化をもたらし、そのｒの変化が今度はＭ１とＭ２をそれぞれ変化させるが、この二つを合わせると
最初のＭの変化になる。なぜならＹの一部はｒに依存するからである。
(ii) It is not always made clear whether the income-velocity of money
is defined as the ratio of Y to M or as the ratio of Y to M1. I
propose, however, to take it in the latter sense. Thus if V is the
income-velocity of money,
L1(Y) = Y/V = M1.
（ニ）貨幣の所得速度の定義はＹとＭの割合（＝Ｙ／Ｍ）なのかＹとＭ１の割合（＝Ｙ／Ｍ１）なのかは必ずしも明らかではない。しかしながら、私は後者の定義を採用したい。つまり、∨を貨幣の所得速度とすると、
Ｌ１（Ｙ）＝ Ｙ／∨ ＝ Ｍ１ となる。
There is, of course, no reason for supposing that V is constant. Its
value will depend on the character of banking and industrial
organisation, on social habits, on the distribution of income between
different classes and on the effective cost of holding idle cash.
Nevertheless, if we have a short period of time in view and can safely
assume no material change in any of these factors, we can treat V as
nearly enough constant.
もちろん、∨が固定していると想定する理由はない。その値は銀行と産業組織の性格、社会習慣、所得の階級間の分配、遊休現金を保有する実際の費用に依存す
る。にもかかわらず、短期を視野においてこれらの要素に大きな変化がないと想定するなら、我々は∨を定数であると見做してよい。
(iii) Finally there is the question of the relation between M2 and r.
We have seen in Chapter 13 that uncertainty as to the future course of
the rate of interest is the sole intelligible explanation of the type
of liquidity-preference L2 which leads to the holding of cash M2. It
follows that a given M2 will not have a definite quantitative relation
to a given rate of interest of r; ― what matters is not the absolute
level of r but the degree of its divergence from what is considered a
fairly safe level of r, having regard to those calculations of
probability which are being relied on. Nevertheless, there are two
reasons for expecting that, in any given state of expectation, a fall
in r will be associated with an increase in M2. In the first place, if
the general view as to what is a safe level of r is unchanged, every
fall in r reduces the market rate relatively to the “safe” rate and
therefore increases the risk of illiquidity; and, in the second place,
every fall in r reduces the current earnings from illiquidity, which
are available as a sort of insurance premium to offset the risk of loss
on capital account, by an amount equal to the difference between the
squares of the old rate of interest and the new.
（三）最後にＭ２とｒの関係の問題が残る。第１３章で我々は、現金Ｍ２の保有を促す流動性選好Ｌ２を唯一つ合理的に説明するのは将来の利子率の不確定性が
であることを見出した。すると、あるＭ２がある利子率ｒと量的に明確な関係にあるのではないということになる。―重要な事は、ｒがいくらであるかではな
く、信頼できる確立計算を尊重した場合、ｒが充分に安全な水準からどれだけ離れているかなのである。にもかかわらず、期待を一定とすると、ｒの下落がＭ２
の増加を伴うと予想する二つの理由がある。まず第一に、ｒの安全な水準についての一般的な見方を一定とすると、ｒの下落は市場利子率を相対的に「安全な利
子率」よりも引き下げ、したがって、非流動性（＝債券）のリスクを増加するからであり、第二に、ｒの下落は（資本勘定における損失リスクを相殺する保険プ
レミアムとして利用可能な）非流動性からの当座の収益を、古い利子率の二乗と新たな利子率の二乗の差に等しい額だけ引き下げるからである。
For example, if the rate of interest on a long-term debt is 4 per
cent., it is preferable to sacrifice liquidity unless on a balance of
probabilities it is feared that the long-term rate of interest may rise
faster than by 4 per cent. of itself per annum, i.e. by an amount
greater than 0.16 per cent. per annum. If, however, the rate of
interest is already as low as 2 per cent., the running yield will only
offset a rise in it of as little as 0.04 per cent. per annum. This,
indeed, is perhaps the chief obstacle to a fall in the rate of interest
to a very low level. Unless reasons are believed to exist why future
experience will be very different from past experience, a long-term
rate of interest of (say) 2 per cent. leaves more to fear than to hope,
and offers, at the same time, a running yield which is only sufficient
to offset a very small measure of fear.
例えば、もし長期債権の利子率が４％なら、長期利子率が年にそれ自身（＝４％）の４％以上つまり年に０．１６％以上上昇する恐れが確率的にないときは、流
動性を手放すのが望ましい。しかしながら、もし利子率がすでに２％にまで下がっているなら、当座の収益はわずか年０．０４％の上昇分を埋め合わせするだけ
である（＝流動性を保持するのが望ましい）。確かに、恐らく主にこの事によって利子率があまり低い水準に下がることをくい止められているのである。きっと
未来の体験は過去とは違うはずだと信じる理由がないかぎり、長期の利子率が（例えば）２％である場合には希望より不安の方が多いし、そこから得られる当座
の収益も気休め程度でしかない。
It is evident, then, that the rate of interest is a highly
psychological phenomenon. We shall find, <indeed ,in Book V that it
cannot be> in equilibrium at a level below the rate which
corresponds to full employment; because at such a level a state of true
inflation will be produced, with the result that M1 will absorb
ever-increasing quantities of cash. But at a level above the rate which
corresponds to full employment, the long-term market-rate of interest
will depend, not only on the current policy of the monetary authority,
but also on market expectations concerning its future policy. The
short-term rate of interest is easily controlled by the monetary
authority, both because it is not difficult to produce a
conviction（確信度） that its policy will not greatly change in the very
near future, and also because the possible loss is small compared with
the running yield (unless it is approaching vanishing point). But the
long-term rate may be more recalcitrant when once it has fallen to a
level which, on the basis of past experience and present expectations
of future monetary policy, is considered “unsafe” by representative
opinion. For example, in a country linked to an international gold
standard（金本位制）, a rate of interest lower than prevails elsewhere will
be viewed with a justifiable lack of confidence（確信度の欠如）; yet a domestic
rate of interest dragged up to a parity with the highest rate (highest
after allowing for risk) prevailing in any country belonging to the
international system may be much higher than is consistent with
domestic full employment.
以上から、利子率とは非常に心理的な現象だということは明らかである。確かに、第５巻で我々は、利子率が完全雇用に対応するレベル以下で均衡することはあ
り得ないことを知る。なぜなら、そんな低い利子率では真性インフレーション（＝既出）になってしまい、その結果、増え続ける現金量をＭ１が吸収（→利子率
上昇）することになるからである。しかし、完全雇用に対応する利子率を上回るレベルでは、長期の市場利子率は、貨幣当局の政策によって変化するし、将来の
政策に対する市場の予想によっても変化する。短期の利子率は貨幣当局によって容易にコントロールできる。近い将来に政策が大きく変化することはないという
確信をもたらすことは難しいことではないし、当座の収益（それがゼロに近いものでない限り）と比べて損失の可能性は小さいからである。しかし、長期の利子
率は、過去の経験および将来の金融政策についての現在の予想とに基づく代表的な意見によって「危険」とされるレベルまで一旦下がってしまうと、それを制御
するのはかなり難しい。例えば、国際的な金本位制に結びついている国で、他の地域よりも低い利子率になっていると、それを知った人達は当然確信（＝投資意
欲）を失うだろう。しかし、国内の利子率を金本位制に属する国の一番高い利子率に等しくなるまで（危険を織り込み済みで）引き上げたら、国内の完全雇用と
両立する利子率よりもかなり高い利子率になる可能性がある。
Thus a monetary policy which strikes public opinion as being
experimental in character or easily liable to change may fail in its
objective of greatly reducing the long-term rate of interest, because
M2 may tend to increase almost without limit in response to a reduction
of r below a certain figure. The same policy, on the other hand, may
prove easily successful if it appeals to public opinion as being
reasonable and practicable and in the public interest, rooted in strong
conviction, and promoted by an authority unlikely to be superseded.
つまり、社会にとって試験的な性格のものだと受け取られるような金融政策や、すぐに変化するような金融政策は、長期金利を大きく下げる目的を達成できな
い。なぜなら、ｒがある一定の数字より下がると、それに対応してＭ２が際限なく増加し続けるからである（＝現金が市場に流れない）。一方で、同じ政策で
も、合理的で実行可能で社会のためになると大衆に思われ、強い確信に根ざし、余人に代えがたい権威を持って推進されるなら、容易に成功するだろう。
It might be more accurate, perhaps, to say that the rate of
interest is a highly conventional, rather than a highly psychological,
phenomenon. For its actual value is largely governed by the prevailing
view as to what its value is expected to be. Any level of interest
which is accepted with sufficient conviction as likely to be durable
will be durable; subject, of course, in a changing society to
fluctuations for all kinds of reasons round the expected normal. In
particular, when M1 is increasing faster than M, the rate of interest
will rise, and vice versa. But it may fluctuate for decades about a
level which is chronically too high for full employment; ― particularly
if it is the prevailing opinion that the rate of interest is
self-adjusting, so that the level established by convention is thought
to be rooted in objective grounds much stronger than convention, the
failure of Employment to attain an optimum level being in no way
associated, in the minds either of the public or of authority, with the
prevalence of an inappropriate range of rates of interest.
おそらく、利子率は高度に心理的な現象というよりは高度の慣習的な現象であると言ったほうが正確かもしれない。というのは、利子率の実際の値はその予想さ
れる値についての支配的な意見に大きく左右されるからである。どんな利子率であっても、それが充分な確信を持って安定していると受け取られるものは実際も
安定し続けるのである。もちろん、変化する社会においては予想される標準値の前後で様々な理由から多少変動することはある。特に、Ｍ１がＭより急速に増加
する（＝Ｍ２が減る）と利子率は上昇し、逆にＭがＭ１より急速に増える（＝Ｍ２が増える）と利子率は下落する。しかし、利子率は何十年も完全雇用にとって
は高すぎるレベルで変動することがある。― 特に、利子率は自己調整的というのが支配的な意見で、そのために、慣習の定めた水準が慣習よりも強力な客観的
根拠に基づいていると思われており、さらに、雇用が最高水準に達することが出来ないのは利子率が不適当な範囲にある事とは関係がないと、社会や当局に思わ
れている場合には、そうである。
The difficulties in the way of maintaining effective demand at a
level high enough to provide full employment, which ensue from the
association of a conventional and fairly stable long-term rate of
interest with a fickle and highly unstable marginal efficiency of
capital, should be, by now, obvious to the reader.
完全雇用をもたらす充分な有効需要を維持する妨げとなっている様々な困難は、慣習的でかなり安定した長期の利子率と、気まぐれて極めて不安定な資本の限界効率の組み合わせから生まれていることは、もはや読者には明らかだろう。
Such comfort as we can fairly take from more encouraging
reflections must be drawn from the hope that, precisely because the
convention is not rooted in secure knowledge, it will not be always
unduly resistant to a modest measure of persistence and consistency of
purpose by the monetary authority. Public opinion can be fairly rapidly
accustomed to a modest fall in the rate of interest and the
conventional expectation of the future may be modified accordingly;
thus preparing the way for a further movement ― up to a point. The fall
in the long-term rate of interest in Great Britain after her departure
from the gold standard provides an interesting example of this; ― the
major movements were effected by a series of discontinuous jumps, as
the liquidity function of the public, having become accustomed to each
successive reduction, became ready to respond to some new incentive in
the news or in the policy of the authorities.
もっと楽観的に考えて、慣習は確実な知識に根ざしているものではないから、貨幣当局が適度に粘り強く一貫した目的をもっているなら、慣習もそれほど強く
抵抗しないだろうと考えるのは、多少の気休めになるかもしれない。それに、世論は利子率の適度な下落にかなり急速に慣れるし、将来に対する慣習的な予想も
それに応じて変えることが出来る。つまり変化への道筋は準備されているのである―ある程度までだが。金本位制を離脱したあとの英国の長期金利の下落はこの
興味深い実例を与えている。―社会の流動性関数が連続的な下落に慣れていたので、新たな情勢や当局の政策による新しい刺激に反応する準備ができていたの
で、英国では大きな変化（＝利子率の低下）が連続的なジャンプによって引き起こされたのである。
III
We can sum up the above in the proposition that in any given
state of expectation there is in the minds of the public a certain
potentiality towards holding cash beyond what is required by the
transactions-motive or the precautionary-motive, which will realise
itself in actual cash-holdings in a degree which depends on the terms
on which the monetary authority is willing to create cash. It is this
potentiality which is summed up in the liquidity function L2.
第３節
これまでのところを要約すると、一定の予想のもとで、社会は心理的に取引動機と予備的動機によって必要とされる（＝Ｍ１）以上の現金を保有しようとする
潜在的傾向があって、それが現実の貨幣保有となる程度は、貨幣当局が貨幣創造をしようとする条件（＝利子率）に依存する。この潜在的傾向が流動性関数Ｌ２
に要約されているのである。
Corresponding to the quantity of money created by the monetary
authority, there will, therefore, be cet. par. a determinate（被決定の） rate
of interest or, more strictly, a determinate complex of rates of
interest for debts of different maturities. The same thing, however,
would be true of any other factor in the economic system taken
separately. Thus this particular analysis will only be useful and
significant in so far as there is some specially direct or purposive
connection between changes in the quantity of money and changes in the
rate of interest. Our reason for supposing that there is such a special
connection arises from the fact that, broadly speaking, the banking
system and the monetary authority are dealers in money and debts and
not in assets or consumables.
したがって、他の条件が同じなら、貨幣当局が創造した貨幣量に対応して、利子率、もっと厳密には、様々な満期をもつ債権の利子率複合体が決定されることに
なる。しかしながら、経済の他のどの要素でも個別に取り上げると、同じことが当てはまる（＝貨幣量以外によって利子率が決まることもある）。つまり、貨幣
量の変化と利子率の変化の間に特に直接的なつながり、目的にかなったつながりがある場合にだけ、この特別な分析（＝貨幣量と利子率の対応）が有用であり有
意義となる。そのような特別なつながりがあると考える一つの理由は、概して銀行と貨幣当局は貨幣と債権を扱うだけで、資産や消費財を扱わないからである。
If the monetary authority were prepared to deal both ways on
specified terms in debts of all maturities, and even more so if it were
prepared to deal in debts of varying degrees of risk, the relationship
between the complex of rates of interest and the quantity of money
would be direct. The complex of rates of interest would simply be an
expression of the terms on which the banking system is prepared to
acquire or part with debts; and the quantity of money would be the
amount which can find a home in the possession of individuals who ―
after taking account of all relevant circumstances ― prefer the control
of liquid cash to parting with it in exchange for a debt on the terms
indicated by the market rate of interest. Perhaps a complex offer by
the central bank to buy and sell at stated prices gilt-edged bonds of
all maturities, in place of the single bank rate for short-term bills,
is the most important practical improvement which can be made in the
technique of monetary management.
もし貨幣当局が指定した条件であらゆる満期の債権を売り買い両方向で取り扱う準備ができているなら、そして、さらに様々なリスクの債権を扱う準備ができ
ているなら、利子率複合体と貨幣量の関係は直接的になる。そうすると、利子率複合体は単に銀行が債権を買い入れるか手放すかの用意がある条件の表現でしか
ないだろう。そして貨幣量とは、―
関係するあらゆる状況を考えた後に― 市場利子率として表れた条件で債権と交換に流動的現金を手放すよりは流動的現金を持ち続ける方を選ぶ人の所有に帰す
る量となる。おそらく中央銀行が、短期の証券に対する単一の銀行利子率の代わりに、あらゆる満期の優良債券を指定した価格で売買することを組み合わせて提
示するようになった事は、貨幣管理の技術の最も重要な実践的進歩である。
To-day, however, in actual practice, the extent to which the
price of debts as fixed by the banking system is “effective” in the
market, in the sense that it governs the actual market-price, varies in
different systems（経済システム）. Sometimes the price is more effective in one
direction than in the other; that is to say, the banking system may
undertake to purchase debts at a certain price but not necessarily to
sell them at a figure near enough to its buying-price to represent no
more than a dealer's turn, though there is no reason why the price
should not be made effective both ways with the aid of open-market
operations. There is also the more important qualification which arises
out of the monetary authority not being, as a rule, an equally willing
dealer in debts of all maturities. The monetary authority often tends
in practice to concentrate upon short-term debts and to leave the price
of long-term debts to be influenced by belated and imperfect reactions
from the price of short-term debts; ― though here again there is no
reason why they need do so.
しかしながら、今日の実際の慣例では、銀行が決めた債権価格が、どれほど現実の市場価格に決定力をもつかという意味で、市場で「有効」となる程度は、それ
ぞれの経済によって異なっている。時々その価格は売買の一つの向きより反対向きのほうが「有効」であることがある。つまり、銀行は債権をある価格で購入し
ようとしても、必ずしも、その購入価格と近い価格、ディーラーの値ざやしか表さないような価格で売るとは限らない。とはいえ、その価格が公開市場操作の力
で売買の両方向に「有効」とならない理由はない。また、貨幣当局が一般的に全期間の債権を同じように扱おうとはしないということから来る更に重要な限定条
件がある。つまり、貨幣当局はしばしば実際には短期の債権に集中して、長期の債権価格は後になって短期の債権価格から不完全な影響を受けるに任せる傾向が
あるのだ。―とはいえ、ここでもまた必ず彼らがそうする理由はない。
Where these qualifications operate, the directness of the relation
between the rate of interest and the quantity of money is
correspondingly modified. In Great Britain the field of deliberate
control appears to be widening. But in applying this theory in any
particular case allowance must be made for the special characteristics
of the method actually employed by the monetary authority. If the
monetary authority deals only in short-term debts, we have to consider
what influence the price, actual and prospective, of short-term debts
exercises on debts of longer maturity.
このような限定条件が働く場合には、利子率と貨幣量との関係の直接性はそれに応じて緩和される。英国では意図的なコントロールの範囲は広がっているように
見える。しかし、この理論を個別のケースに適用するさいには、貨幣当局が実際に採用する方法の特殊な性格を考慮に入れる必要がある。もし貨幣当局が短期債
権だけを扱うなら、短期債権の現在と将来の価格が長期の債権にどういう影響を与えるかを考えなければならない。
Thus there are certain limitations on the ability of the
monetary authority to establish any given complex of rates of interest
for debts of different terms and risks, which can be summed up as
follows:
つまり、貨幣当局が様々な条件やリスクの債権の複合利子率を確立する能力にはある種の限界がある。それを以下に要約しよう。
(1) There are those limitations which arise out of the monetary
authority's own practices in limiting its willingness to deal to debts
of a particular type.
（１）貨幣当局が特定のタイプの債権を扱いたがる自分の習慣からくる限界
(2) There is the possibility, for the reasons discussed above, that,
after the rate of interest has fallen to a certain level,
liquidity-preference may become virtually absolute in the sense that
almost everyone prefers cash to holding a debt which yields so low a
rate of interest. In this event the monetary authority would have lost
effective control over the rate of interest. But whilst this limiting
case might become practically important in future, I know of no example
of it hitherto. Indeed, owing to the unwillingness of most monetary
authorities to deal boldly in debts of long term, there has not been
much opportunity for a test. Moreover, if such a situation were to
arise, it would mean that the public authority itself could borrow
through the banking system on an unlimited scale at a nominal rate of
interest.
（２）上で述べた理由から、利子率がある水準に低下したあとは、殆どすべての人がそれほど低い利子しかもたらさない債権を持つよりは現金を持つ方を選ぶと
いう意味で、流動性選好がほとんど絶対的になる可能性がある。こうなったら、貨幣当局は利子率に対して効果的なコントロールを失ってしまう（＝流動性の
罠）。しかし、このような限定的なケースは将来において実際上は重要になるが、これまでのところそんな例を知らない。確かに、多くの貨幣当局が長期の債権
を大胆に扱うことを嫌がるために、コントロールを失うほどの利子率の低下を試す機会は多くなかった。さらに、もしそんな状況が発生したら、それは公共団体
が名ばかりの利子率でいくらでも銀行を通じて借入れすることが出来ることを意味している。
(3) The most striking examples of a complete breakdown of stability in
the rate of interest, due to the liquidity function flattening out in
one direction or the other, have occurred in very abnormal
circumstances. In Russia and Central Europe after the war a currency
crisis or flight from the currency was experienced, when no one could
be induced to retain holdings either of money or of debts on any terms
whatever, and even a high and rising rate of interest was unable to
keep pace with the marginal efficiency of capital (especially of stocks
of liquid goods) under the influence of the expectation of an ever
greater fall in the value of money; whilst in the United States at
certain dates in 1932 there was a crisis of the opposite kind ― a
financial crisis or crisis of liquidation, when scarcely anyone could
be induced to part with holdings of money on any reasonable terms.
（３）流動性関数がどちらかの方向に完全に平たくなったことに起因して、利子率の安定性が完全に崩壊した最も衝撃的な例は、非常に異常な状況の中で発生し
た。第一次大戦後のロシアや中央ヨーロッパでは通貨危機、つまり通貨からの逃避が経験された。当時は誰もが貨幣の保有もどんな条件での債権の保有もする気
持ちがなくなった（＝金や現物を持ちたがる）。また、貨幣価値がさらに大きく下落すると予想されたおかげで、どんなに利子率が上昇しても、資本の限界効率
（物価上昇で特に流動的な財の在庫の価値が上昇）の上昇する歩調（＝既出）について行く事ができなかった。一方、合衆国では１９３２年のある日、逆方向の
危機が発生した。金融恐慌あるいは清算恐慌である。その時はほとんど誰もどんな条件でも貨幣の保有をやめる気にはなれなかった。
(4) There is, finally, the difficulty discussed in section iv of
Chapter 11, p. 144, in the way of bringing the effective rate of
interest below a certain figure, which may prove important in an era of
low interest-rates; namely the intermediate costs（仲介手数料） of bringing
the borrower and the ultimate lender together, and the allowance for
risk, especially for moral risk, which the lender requires over and
above（～に加えて） the pure rate of interest（＝既出）. As the pure rate of
interest declines it does not follow that the allowances for
expense（＝上の仲介手数料） and risk decline pari passu. Thus the rate of
interest which the typical borrower has to pay may decline more slowly
than the pure rate of interest, and may be incapable of being brought,
by the methods of the existing banking and financial organisation,
below a certain minimum figure. This is particularly important if the
estimation（推定） of moral risk is appreciable. For where the risk is due
to doubt in the mind of the lender concerning the honesty of the
borrower, there is nothing in the mind of a borrower who does not
intend to be dishonest to offset the resultant higher charge. It is
also important in the case of short-term loans (e.g. bank loans) where
the expenses are heavy; ― a bank may have to charge its customers 1 1/2
to 2 per cent., even if the pure rate of interest to the lender is nil.
（４）１４４頁の第１１章第４節「リスクについて」で論じたある種の障害があって、それが「有効」利子率を一定以下にすることをさまたげている。低利子率
の時代には深刻な問題で、それは借り手と究極的貸し手とを引き合わせるための仲介手数料と、貸し手が純粋利子率に加えて要求するリスクの引当金、特にモラ
ルリスクの引当金である。純粋利子率が下落しても、それに歩調を合わせて手数料とリスクの引当金が下がるわけではない。つまり、典型的な借り手が支払わね
ばならない利子率は、純粋利子率よりも下落が遅いので、現行の銀行組織と金融組織の方法によってはある最少の数字以下に下げることが出来ない。このこと
は、もしモラルリスクの推定がかなり大きいものなら特に深刻である。というのは、リスクが借手の誠実さに対する貸手の疑念から来るものなら、不誠実なつも
りのない借手の心にはそんな追加料金を支払う理由は何もないからである。また、手数料が高くつく短期ローン（例えば銀行のローン）の場合も深刻である。―
たとえ貸手にとっては純粋利子率はゼロであっても、銀行は顧客に対して１．５％から２％の利子を課さねばならないからである。
IV
At the cost of anticipating what is more properly the subject of
Chapter 21 below it may be interesting briefly at this stage to
indicate the relationship of the above to the Quantity Theory of Money.
第４節
第２１章のテーマとするほうが相応しいことを先取りすることになるが、この段階で簡単にこの章の問題と貨幣数量節との関係を指摘しておくことは興味深い。
In a static society or in a society in which for any other
reason no one feels any uncertainty about the future rates of interest,
the Liquidity Function L2 or the propensity to hoard (as we might term
it), will always be zero in equilibrium. Hence in equilibrium M2 = 0
and M = M1; so that any change in M will cause the rate of interest to
fluctuate until income reaches a level at which the change in M1 is
equal to the supposed change in M. Now M1V = Y, where V is the
income-velocity of money as defined above and Y is the aggregate
income. Thus if it is practicable to measure the quantity, 0, and the
price, P, of current output, we have Y = OP, and, therefore, MV = OP;
which is much the same as the Quantity Theory of Money in its
traditional form.[2]
静的な社会、あるいは誰も将来の利子率について不確定性を感じないような社会では、流動性関数Ｌ２あるいは（こういっていいのなら）保蔵性向は均衡におい
て常にゼロになる。したがって、均衡においてはＭ２＝０であってＭ＝Ｍ１ということになる。つまり、Ｍの変化は利子率を変化させて、それはＭ１の変化がＭ
の変化と等しくなるような（＝Ｍ２がゼロになるような）所得レベルに達するまで続くということである。その時、Ｍ１×∨＝Ｙが成り立つ。ここで、∨は上記
で定義した貨幣の所得速度でありＹは総所得である。つまり、もし産出物の量Ｏと価格Ｐが計測できるなら、Ｙ＝Ｏ×Ｐであり、したがって、Ｍ×∨＝Ｏ×Ｐ
（←Ｍ１＝Ｍ）である。これは貨幣数量説の伝統的な式とほぼ同じである[２]。
For the purposes of the real world it is a great fault in the
Quantity Theory that it does not distinguish between changes in prices
which are a function of changes in output, and those which are a
function of changes in the wage-unit.[3] The explanation of this
omission is, perhaps, to be found in the assumptions that there is no
propensity to hoard and that there is always full employment. For in
this case, O being constant and M2 being zero, it follows, if we can
take V also as constant, that both the wage-unit and the price-level
will be directly proportional to the quantity of money.
現実の世界にとっては貨幣数量説は大きな欠陥がある。それは産出量の変化の関数である物価の変化と、単位賃金の変化の関数である物価の変化を区別していな
ことである[３]。この欠陥はおそらく保蔵性向がなく常に完全雇用状態であるという想定のせいだろう。というのは、この場合、Ｏは定数でありＭ２はゼロで
あり、それはすなわち、もし∨も定数に出来るなら、単位賃金と物価水準は貨幣量に直接比例することになるからである。
Author's Footnotes
[1]. We must postpone to Book V. the question of what will determine the character of the new equilibrium.
[2]. If we had defined V, not as equal to Y/M1, but as equal to Y/M,
then, of course, the Quantity Theory is a truism which holds in all
circumstances, though without significance.
[3]. This point will be further developed in Chapter 21 below.
著者注
[１] 新たな均衡の性格を決めるものは何かという問題は第５巻に先送りする。
[２] もし∨をＹ／Ｍ１ではなくＹ／Ｍに等しいとするなら、もちろん貨幣数量説はもはや自明の理であり、どんな状況でも当てはまるが何の意味もなくなってしまう。
[３] この点は２１章でさらに扱う。
※第１６章以下は訳しているところもある。
Chapter 16. Sundry Observations on the Nature of Capital
I
AN act of individual saving means ― so to speak ― a decision not to
have dinner to-day. But it does not necessitate a decision to have
dinner or to buy a pair of boots a week hence or a year hence or to
consume any specified thing at any specified date. Thus it depresses
the business（本文、務め） of preparing to-day's dinner without stimulating
the business of making ready for some future act of consumption. It is
not a substitution of future consumption-demand for present
consumption-demand, ― it is a net diminution of such demand. Moreover,
the expectation of future consumption is so largely based on current
experience of present consumption that a reduction in the latter is
likely to depress the former, with the result that the act of saving
will not merely depress the price of consumption-goods and leave the
marginal efficiency of existing capital unaffected, but may actually
tend to depress the latter also. In this event it may reduce present
investment-demand as well as present consumption-demand.
If saving consisted not merely in abstaining from present
consumption but in placing simultaneously a specific order for future
consumption, the effect might indeed be different. For in that case the
expectation of some future yield from investment would be improved, and
the resources released from preparing for present consumption could be
turned over to preparing for the future consumption. Not that they
necessarily would be, even in this case, on a scale equal to the amount
of resources released; since the desired interval of delay might
require a method of production so inconveniently “roundabout” as to
have an efficiency well below the current rate of interest, with the
result that the favourable effect on employment of the forward order
for consumption would eventuate not at once but at some subsequent
date, so that the immediate effect of the saving would still be adverse
to employment. In any case, however, an individual decision to save
does not, in actual fact, involve the placing of any specific forward
order for consumption, but merely the cancellation of a present order.
Thus, since the expectation of consumption is the only raison d'e^tre
of employment, there should be nothing paradoxical in the conclusion
that a diminished propensity to consume has cet. par. a depressing
effect on employment.
The trouble arises, therefore, because the act of saving implies, not a
substitution for present consumption of some specific additional
consumption which requires for its preparation just as much immediate
economic activity as would have been required by present consumption
equal in value to the sum saved, but a desire for “wealth” as such,
that is for a potentiality of consuming an unspecified article at an
unspecified time. The absurd, though almost universal, idea that an act
of individual saving is just as good for effective demand as an act of
individual consumption, has been fostered by the fallacy, much more
specious than the conclusion derived from it, that an increased desire
to hold wealth, being much the same thing as an increased desire to
hold investments, must, by increasing the demand for investments,
provide a stimulus to their production; so that current investment is
promoted by individual saving to the same extent as present consumption
is diminished.
It is of this fallacy that it is most difficult to disabuse
men's minds. It comes from believing that the owner of wealth desires a
capital-asset as such, whereas what he really desires is its
prospective yield. Now, prospective yield wholly depends on the
expectation of future effective demand in relation to future conditions
of supply. If, therefore, an act of saving does nothing to improve
prospective yield, it does nothing to stimulate investment. Moreover,
in order that an individual saver may attain his desired goal of the
ownership of wealth, it is not necessary that a new capital-asset
should be produced wherewith to satisfy him. The mere act of saving by
one individual, being two-sided as we have shown above, forces some
other individual to transfer to him some article of wealth old or new.
Every act of saving involves a “forced” inevitable transfer of wealth
to him who saves, though he in his turn may suffer from the saving of
others. These transfers of wealth do not require the creation of new
wealth ― indeed, as we have seen, they may be actively inimical to it.
The creation of new wealth wholly depends on the prospective yield of
the new wealth reaching the standard set by the current rate of
interest. The prospective yield of the marginal new investment is not
increased by the fact that someone wishes to increase his wealth, since
the prospective yield of the marginal new investment depends on the
expectation of a demand for a specific article at a specific date.
Nor do we avoid this conclusion by arguing that what the owner of
wealth desires is not a given prospective yield but the best available
prospective yield, so that an increased desire to own wealth reduces
the prospective yield with which the producers of new investment have
to be content. For this overlooks the fact that there is always an
alternative to the ownership of real capital-assets, namely the
ownership of money and debts; so that the prospective yield with which
the producers of new investment have to be content cannot fall below
the standard set by the current rate of interest. And the current rate
of interest depends, as we have seen, not on the strength of the desire
to hold wealth, but on the strengths of the desires to hold it in
liquid and in illiquid forms respectively, coupled with the amount of
the supply of wealth in the one form relatively to the supply of it in
the other. If the reader still finds himself perplexed, let him ask
himself why, the quantity of money being unchanged, a fresh act of
saving should diminish the sum which it is desired to keep in liquid
form at the existing rate of interest.
Certain deeper perplexities, which may arise when we try to probe still
further into the whys and wherefores, will be considered in the next
chapter.
II
It is much preferable to speak of capital as having a yield over
the course of its life in excess of its original cost, than as being
productive. For the only reason why an asset offers a prospect of
yielding during its life services having an aggregate value greater
than its initial supply price is because it is scarce; and it is kept
scarce because of the competition of the rate of interest on money. If
capital becomes less scarce, the excess yield will diminish, without
its having become less productive ― at least in the physical sense.
I sympathise, therefore, with the pre-classical doctrine that
everything is produced by labour, aided by what used to be called art
and is now called technique, by natural resources which are free or
cost a rent according to their scarcity or abundance, and by the
results of past labour, embodied in assets, which also command a price
according to their scarcity or abundance. It is preferable to regard
labour, including, of course, the personal services of the entrepreneur
and his assistants, as the sole factor of production, operating in a
given environment of technique, natural resources, capital equipment
and effective demand. This partly explains why we have been able to
take the unit of labour as the sole physical unit which we require in
our economic system, apart from units of money and of time.
It is true that some lengthy or roundabout processes are
physically efficient. But so are some short processes. Lengthy
processes are not physically efficient because they are long. Some,
probably most, lengthy processes would be physically very inefficient,
for there are such things as spoiling or wasting with time.[1] With a
given labour force there is a definite limit to the quantity of labour
embodied in roundabout processes which can be used to advantage. Apart
from other considerations, there must be a due proportion between the
amount of labour employed in making machines and the amount which will
be employed in using them. The ultimate quantity of value will not
increase indefinitely, relatively to the quantity of labour employed,
as the processes adopted become more and more roundabout, even if their
physical efficiency is still increasing. Only if the desire to postpone
consumption were strong enough to produce a situation in which full
employment required a volume of investment so great as to involve a
negative marginal efficiency of capital, would a process become
advantageous merely because it was lengthy; in which event we should
employ physically inefficient processes, provided they were
sufficiently lengthy for the gain from postponement to outweigh their
inefficiency. We should in fact have a situation in which short
processes would have to be kept sufficiently scarce for their physical
efficiency to outweigh the disadvantage of the early delivery of their
product. A correct theory, therefore, must be reversible so as to be
able to cover the cases of the marginal efficiency of capital
corresponding either to a positive or to a negative rate of interest;
and it is, I think, only the scarcity theory outlined above which is
capable of this.
Moreover there are all sorts of reasons why various kinds of services
and facilities are scarce and therefore expensive relatively to the
quantity of labour involved. For example, smelly processes command a
higher reward, because people will not undertake them otherwise. So do
risky processes. But we do not devise a productivity theory of smelly
or risky processes as such. In short, not all labour is accomplished in
equally agreeable attendant circumstances; and conditions of
equilibrium require that articles produced in less agreeable attendant
circumstances (characterised by smelliness, risk or the lapse of time)
must be kept sufficiently scarce to command a higher price. But if the
lapse of time becomes an agreeable attendant circumstance, which is a
quite possible case and already holds for many individuals, then, as I
have said above, it is the short processes which must be kept
sufficiently scarce.
Given the optimum amount of roundaboutness, we shall, of course, select
the most efficient roundabout processes which we can find up to the
required aggregate. But the optimum amount itself should be such as to
provide at the appropriate dates for that part of consumers' demand
which it is desired to defer. In optimum conditions, that is to say,
production should be so organised as to produce in the most efficient
manner compatible with delivery at the dates at which consumers' demand
is expected to become effective. It is no use to produce for delivery
at a different date from this, even though the physical output could be
increased by changing the date of delivery; ― except in so far as the
prospect of a larger meal, so to speak, induces the consumer to
anticipate or postpone the hour of dinner. If, after hearing full
particulars of the meals he can get by fixing dinner at different
hours, the consumer is expected to decide in favour of 8 o'clock, it is
the business of the cook to provide the best dinner he can for service
at that hour, irrespective of whether 7.30, 8 o'clock or 8.30 is the
hour which would suit him best if time counted for nothing, one way or
the other, and his only task was to produce the absolutely best dinner.
In some phases of society it may be that we could get physically better
dinners by dining later than we do; but it is equally conceivable in
other phases that we could get better dinners by dining earlier. Our
theory must, as I have said above, be applicable to both contingencies.
If the rate of interest were zero, there would be an optimum
interval for any given article between the average date of input and
the date of consumption, for which labour cost would be a minimum; ― a
shorter process of production would be less efficient technically,
whilst a longer process would also be less efficient by reason of
storage costs and deterioration. If, however, the rate of interest
exceeds zero, a new element of cost is introduced which increases with
the length of the process, so that the optimum interval will be
shortened, and the current input to provide for the eventual delivery
of the article will have to be curtailed until the prospective price
has increased sufficiently to cover the increased cost ― a cost which
will be increased both by the interest charges and also by the
diminished efficiency of the shorter method of production. Whilst if
the rate of interest falls below zero (assuming this to be technically
possible), the opposite is the case. Given the prospective consumers'
demand, current input to-day has to compete, so to speak, with the
alternative of starting input at a later date; and, consequently,
current input will only be worth while when the greater cheapness, by
reason of greater technical efficiency or prospective price changes, of
producing later on rather than now, is insufficient to offset the
smaller return from negative interest. In the case of the great
majority of articles it would involve great technical inefficiency to
start up their input more than a very modest length of time ahead of
their prospective consumption. Thus even if the rate of interest is
zero, there is a strict limit to the proportion of prospective
consumers' demand which it is profitable to begin providing for in
advance; and, as the rate of interest rises, the proportion of the
prospective consumers' demand for which it pays to produce to-day
shrinks pari passu.
III
We have seen that capital has to be kept scarce enough in the
long-period to have a marginal efficiency which is at least equal to
the rate of interest for a period equal to the life of the capital, as
determined by psychological and institutional conditions. What would
this involve for a society which finds itself so well equipped with
capital that its marginal efficiency is zero and would be negative with
any additional investment; yet possessing a monetary system, such that
money will “keep” and involves negligible costs of storage and safe
custody, with the result that in practice interest cannot be negative;
and, in conditions of full employment, disposed to save?
If, in such circumstances, we start from a position of full
employment, entrepreneurs will necessarily make losses if they continue
to offer employment on a scale which will utilise the whole of the
existing stock of capital. Hence the stock of capital and the level of
employment will have to shrink until the community becomes so
impoverished that the aggregate of saving has become zero, the positive
saving of some individuals or groups being offset by the negative
saving of others. Thus for a society such as we have supposed, the
position of equilibrium, under conditions of laissez-faire, will be one
in which employment is low enough and the standard of life sufficiently
miserable to bring savings to zero. More probably there will be a
cyclical movement round this equilibrium position. For if there is
still room for uncertainty about the future, the marginal efficiency of
capital will occasionally rise above zero leading to a “boom”, and in
the succeeding “slump” the stock of capital may fall for a time below
the level which will yield a marginal efficiency of zero in the long
run. Assuming correct foresight, the equilibrium stock of capital which
will have a marginal efficiency of precisely zero will, of course, be a
smaller stock than would correspond to full employment of the available
labour; for it will be the equipment which corresponds to that
proportion of unemployment which ensures zero saving.
The only alternative position of equilibrium would be given by a
situation in which a stock of capital sufficiently great to have a
marginal efficiency of zero also represents an amount of wealth
sufficiently great to satiate to the full the aggregate desire on the
part of the public to make provision for the future, even with full
employment, in circumstances where no bonus is obtainable in the form
of interest. It would, however, be an unlikely coincidence that the
propensity to save in conditions of full employment should become
satisfied just at the point where the stock of capital reaches the
level where its marginal efficiency is zero. If, therefore, this more
favourable possibility comes to the rescue, it will probably take
effect, not just at the point where the rate of interest is vanishing,
but at some previous point during the gradual decline of the rate of
interest.
We have assumed so far an institutional factor which prevents the rate
of interest from being negative, in the shape of money which has
negligible carrying-costs（持越費用、在庫維持費）. In fact, however, institutional
and psychological factors are present which set a limit much above zero
to the practicable decline in the rate of interest. In particular the
costs of bringing borrowers and lenders together and uncertainty as to
the future of the rate of interest, which we have examined above, set a
lower limit, which in present circumstances may perhaps be as high as 2
or 2 1/2 per cent. on long term. If this should prove correct, the
awkward possibilities of an increasing stock of wealth, in conditions
where the rate of interest can fall no further under laissez-faire, may
soon be realised in actual experience. Moreover if the minimum level to
which it is practicable to bring the rate of interest is appreciably
above zero, there is less likelihood of the aggregate desire to
accumulate wealth being satiated before the rate of interest has
reached its minimum level.
The post-war experiences of Great Britain and the United States are,
indeed, actual examples of how an accumulation of wealth, so large that
its marginal efficiency has fallen more rapidly than the rate of
interest can fall in the face of the prevailing institutional and
psychological factors, can interfere, in conditions mainly of
laissez-faire, with a reasonable level of employment and with the
standard of life which the technical conditions of production are
capable of furnishing.
It follows that of two equal communities, having the same
technique but different stocks of capital, the community with the
smaller stock of capital may be able for the time being to enjoy a
higher standard of life than the community with the larger stock;
though when the poorer community has caught up the rich ― as,
presumably, it eventually will ― then both alike will suffer the fate
of Midas. This disturbing conclusion depends, of course, on the
assumption that the propensity to consume and the rate of investment
are not deliberately controlled in the social interest but are mainly
left to the influences of laissez-faire.
If ― for whatever reason ― the rate of interest cannot fall as
fast as the marginal efficiency of capital would fall with a rate of
accumulation corresponding to what the community would choose to save
at a rate of interest equal to the marginal efficiency of capital in
conditions of full employment, then even a diversion of the desire to
hold wealth towards assets, which will in fact yield no economic fruits
whatever, will increase economic well-being. In so far as millionaires
find their satisfaction in building mighty mansions to contain their
bodies when alive and pyramids to shelter them after death, or,
repenting of their sins, erect cathedrals and endow monasteries or
foreign missions, the day when abundance of capital will interfere with
abundance of output may be postponed. “To dig holes in the ground,”
paid for out of savings, will increase, not only employment, but the
real national dividend of useful goods and services. It is not
reasonable, however, that a sensible community should be content to
remain dependent on such fortuitous and often wasteful mitigations when
once we understand the influences upon which effective demand depends.
IV
Let us assume that steps are taken to ensure that the rate of interest
is consistent with the rate of investment which corresponds to full
employment. Let us assume, further, that State action enters in as a
balancing factor to provide that the growth of capital equipment shall
be such as to approach saturation-point at a rate which does not put a
disproportionate burden on the standard of life of the present
generation.
On such assumptions I should guess that a properly run community
equipped with modern technical resources, of which the population is
not increasing rapidly, ought to be able to bring down the marginal
efficiency of capital in equilibrium approximately to zero within a
single generation; so that we should attain the conditions of a
quasi-stationary community where change and progress would result only
from changes in technique, taste, population and institutions, with the
products of capital selling at a price proportioned to the labour,
etc., embodied in them on just the same principles as govern the prices
of consumption-goods into which capital-charges enter in an
insignificant degree.
If I am right in supposing it to be comparatively easy to make
capital-goods so abundant that the marginal efficiency of capital is
zero, this may be the most sensible way of gradually getting rid of
many of the objectionable features of capitalism. For a little
reflection will show what enormous social changes would result from a
gradual disappearance of a rate of return on accumulated wealth. A man
would still be free to accumulate his earned income with a view to
spending it at a later date. But his accumulation would not grow. He
would simply be in the position of Pope's father, who, when he retired
from business, carried a chest of guineas with him to his villa at
Twickenham and met his household expenses from it as required.
Though the rentier would disappear, there would still be room,
nevertheless, for enterprise and skill in the estimation of prospective
yields about which opinions could differ. For the above relates
primarily to the pure rate of interest apart from any allowance for
risk and the like, and not to the gross yield of assets including the
return in respect of risk. Thus unless the pure rate of interest were
to be held at a negative figure, there would still be a positive yield
to skilled investment in individual assets having a doubtful
prospective
yield（純粋利子率が負に維持されることがないかぎり、不確かな予想収益を持つ個々の資産に対する熟練した投資には、依然として正の収益が存在するで
あろう）. Provided there was some measurable unwillingness to undertake
risk, there would also be a positive net yield from the aggregate of
such assets over a period of time. But it is not unlikely that, in such
circumstances, the eagerness to obtain a yield from doubtful
investments might be such that they would show in the aggregate a
negative net yield.
利子生活者は消えるとしても、それにもかかわらず、人によって意見の異なる予想収益の評価という技術と冒険心の余地はのこるだろう。というのは、上記の事
実はリスクの要素を排除した純粋利子率に関することで、リスクによる報酬を含めた資産の粗利益に関するものではない。つまり、純粋利子率がマイナスに維持
されることがない限り、不確かな予想収益を持つ個別の資産に対する熟練した投資にはプラスの収益が得られるだろう。さらに、リスクを引き受けることへの明
白な抵抗感があるかぎり、そのような資産を一定期間の後に集計するとプラスの最終収益が生まれていることもある。しかしながら、そのような状況で不確かな
投資から収益をあげようと熱を上げるということは、そのような投資が全体としてマイナスの最終収益を示している可能性があるのが普通である。
Author's Footnotes
[1]. Cf. Marshall's note on Bo"hm-Bawerk, Principles, p. 593.
Chapter 17. The Essential Properties of Interest and Money
I
IT seems, then, that the rate of interest on money plays a
peculiar part in setting a limit to the level of employment, since it
sets a standard to which the marginal efficiency of a capital-asset
must attain if it is to be newly produced. That this should be so, is,
at first sight, most perplexing. It is natural to enquire wherein the
peculiarity of money lies as distinct from other assets, whether it is
only money which has a rate of interest, and what would happen in a
non-monetary economy. Until we have answered these questions, the full
significance of our theory will not be clear.
The money-rate of interest ― we may remind the reader ― is nothing more
than the percentage excess of a sum of money contracted for forward
delivery, e.g. a year hence, over what we may call the “spot” or cash
price of the sum thus contracted for forward delivery. It would seem,
therefore, that for every kind of capital-asset there must be an
analogue of the rate of interest on money. For there is a definite
quantity of (e.g.) wheat to be delivered a year hence which has the
same exchange value to-day as 1000 quarters of wheat for “spot”
delivery. If the former quantity is 105 quarters, we may say that the
wheat-rate of interest is 5 per cent. per annum; and if it is 95
quarters, that it is minus 5 per cent. per annum. Thus for every
durable commodity we have a rate of interest in terms of itself, ― a
wheat-rate of interest, a copper-rate of interest, a house-rate of
interest, even a steel-plant-rate of interest.
The difference between the “future” and “spot” contracts for a
commodity, such as wheat, which are quoted in the market, bears a
definite relation to the wheat-rate of interest, but, since the future
contract is quoted in terms of money for forward delivery and not in
terms of wheat for spot delivery, it also brings in the money-rate of
interest. The exact relationship is as follows:
Let us suppose that the spot price of wheat is ￡100 per 100 quarters,
that the price of the “future” contract for wheat for delivery a year
hence is ￡107 per 100 quarters, and that the money-rate of interest is
5 per cent; what is the wheat-rate of interest? ￡100 spot will buy ￡105
for forward delivery, and ￡105 for forward delivery will buy
(105/107).100 (=98) quarters for forward-delivery. Alternatively ￡100
spot will buy 100 quarters of wheat for spot delivery. Thus 100
quarters of wheat for spot delivery will buy 98 quarters for forward
delivery. It follows that the wheat-rate of interest is minus 2 per
cent. per annum.[1]
It follows from this that there is no reason why their rates of
interest should be the same for different commodities, ― why the
wheat-rate of interest should be equal to the copper-rate of interest.
For the relation between the “spot” and “future” contracts, as quoted
in the market, is notoriously different for different commodities.
This, we shall find, will lead us to the clue we are seeking. For it
may be that it is the greatest of the own-rates of interest (as we may
call them) which rules the roost (because it is the greatest of these
rates that the marginal efficiency of a capital-asset must attain if it
is to be newly produced); and that there are reasons why it is the
money-rate of interest which is often the greatest (because, as we
shall find, certain forces, which operate to reduce the own-rates of
interest of other assets, do not operate in the case of money).
It may be added that, just as there are differing
commodity-rates of interest at any time, so also exchange dealers are
familiar with the fact that the rate of interest is not even the same
in terms of two different moneys, e.g. sterling and dollars. For here
also the difference between the “spot” and “future” contracts for a
foreign money in terms of sterling are not, as a rule, the same for
different foreign moneys.
Now each of these commodity standards offers us the same facility as
money for measuring the marginal efficiency of capital. For we can take
any commodity we choose, eg. wheat; calculate the wheat-value of the
prospective yields of any capital asset; and the rate of discount which
makes the present value of this series of wheat annuities equal to the
present supply price of the asset in terms of wheat gives us the
marginal efficiency of the asset in terms of wheat. If no change is
expected in the relative value of two alternative standards, then the
marginal efficiency of a capital-asset will be the same in whichever of
the two standards it is measured, since the numerator and denominator
of the fraction which leads up to the marginal efficiency will be
changed in the same proportion. If, however, one of the alternative
standards is expected to change in value in terms of the other, the
marginal efficiencies of capital-assets will be changed by the same
percentage, according to which standard they are measured in. To
illustrate this let us take the simplest case where wheat, one of the
alternative standards, is expected to appreciate at a steady rate of a
per cent. per annum in terms of money; the marginal efficiency of an
asset, which is x per cent. in terms of money, will then be x - a per
cent. in terms of wheat. Since the marginal efficiencies of all
capital-assets will be altered by the same amount, it follows that
their order of magnitude will be the same irrespective of the standard
which is selected.
If there were some composite commodity which could be regarded
strictly speaking as representative, we could regard the rate of
interest and the marginal efficiency of capital in terms of this
commodity as being, in a sense, uniquely the rate of interest and the
marginal efficiency of capital. But there are, of course, the same
obstacles in the way of this as there are to setting up a unique
standard of value.
So far, therefore, the money-rate of interest has no uniqueness
compared with other rates of interest, but is on precisely the same
footing. Wherein, then, lies the peculiarity of the money-rate of
interest which gives it the predominating practical importance
attributed to it in the preceding chapters? Why should the volume of
output and employment be more intimately bound up with the money-rate
of interest than with the wheat-rate of interest or the house-rate of
interest?
II
Let us consider what the various commodity-rates of interest over a
period of (say) a year are likely to be for different types of assets.
Since we are taking each commodity in turn as the standard, the returns
on each commodity must be reckoned in this context as being measured in
terms of itself.
There are three attributes which different types of assets possess in different degrees; namely, as follows:
(i) Some assets produce a yield or output q, measured in terms of
themselves, by assisting some process of production or supplying
services to a consumer.
(ii) Most assets, except money, suffer some wastage or involve some
cost through the mere passage of time (apart from any change in their
relative value), irrespective of their being used to produce a yield;
i.e. they involve a carrying-cost c measured in terms of themselves. It
does not matter for our present purpose exactly where we draw the line
between the costs which we deduct before calculating q and those which
we include in c, since in what follows we shall be exclusively
concerned with q - c.
(iii) Finally, the power of disposal over an asset during a period may
offer a potential convenience or security, which is not equal for
assets of different kinds, though the assets themselves are of equal
initial value. There is, so to speak, nothing to show for this at the
end of the period in the shape of output; yet it is something for which
people are ready to pay something. The amount (measured in terms of
itself) which they are willing to pay for the potential convenience or
security given by this power of disposal (exclusive of yield or
carrying-cost attaching to the asset), we shall call its
liquidity-premium（流動性打分、流動性プレミアム） l.
It follows that the total return expected from the ownership of
an asset over a period is equal to its yield minus its carrying-cost
plus its liquidity-premium, i.e. to q - c + l. That is to say, q - c +
l is the own-rate of interest（自己利子率） of any commodity, where q, c and l
are measured in terms of itself as the standard.
It is characteristic of instrumental capital (eg. a machine) or
of consumption capital (eg. a house) which is in use, that its yield
should normally exceed its carrying-cost, whilst its liquidity-premium
is probably negligible; of a stock of liquid goods or of surplus
laid-up instrumental or consumption capital that it should incur a
carrying-cost in terms of itself without any yield to set off against
it（それを相殺する収益を産まないということである）, the liquidity-premium in this case also
being usually negligible as soon as stocks exceed a moderate level,
though capable of being significant in special circumstances; and of
money that its yield is nil, and its carrying-cost negligible, but its
liquidity-premium substantial. Different commodities may, indeed, have
differing degrees of liquidity-premium amongst themselves, and money
may incur some degree of carrying-costs, eg. for safe custody. But it
is an essential difference between money and all (or most) other assets
that in the case of money its liquidity-premium much exceeds its
carrying-cost, whereas in the case of other assets their carrying-cost
much exceeds their liquidity-premium. Let us, for purposes of
illustration, assume that on houses the yield is q1 and the
carrying-cost and liquidity-premium negligible; that on wheat the
carrying-cost is c2 and the yield and liquidity-premium negligible; and
that on money the liquidity-premium is l3 and the yield and
carrying-cost negligible. That is to say, q1 is the house-rate of
interest, -c2 the wheat-rate of interest, and l3 the money-rate of
interest.
To determine the relationships between the expected returns on
different types of assets which are consistent with equilibrium, we
must also know what the changes in relative values during the year are
expected to be. Taking money (which need only be a money of account for
this purpose, and we could equally well take wheat) as our standard of
measurement, let the expected percentage appreciation (or depreciation)
of houses be a1 and of wheat a2. ql, -c2 and l3 we have called the
own-rates of interest of houses, wheat and money in terms of themselves
as the standard of value; i.e. q1 is the house-rate of interest in
terms of houses, -c2 is the wheat-rate of interest in terms of wheat,
and l3 is the money-rate of interest in terms of money. It will also be
useful to call a1 + ql, a2 - c2, and l3, which stand for the same
quantities reduced to money as the standard of value, the house-rate of
money-interest, the wheat-rate of money-interest and the money-rate of
money-interest respectively. With this notation it is easy to see that
the demand of wealth-owners will be directed to houses, to wheat or to
money, according as a1 + q1 or a2 - c2, or l3, is greatest. Thus in
equilibrium the demand-prices of houses and wheat in terms of money
will be such that there is nothing to choose in the way of advantage
between the alternatives; ― i.e. a1 + q1, a2 - c2 and l3 will be equal.
The choice of the standard of value will make no difference to this
result because a shift from one standard to another will change all the
terms equally, i.e. by an amount equal to the expected rate of
appreciation (or depreciation) of the new standard in terms of the old.
Now those assets of which the normal supply-price is less than the
demand-price will be newly produced, and these will be those assets of
which the marginal efficiency would be greater (on the basis of their
normal supply-price) than the rate of interest (both being measured in
the same standard of value whatever it is). As the stock of the assets,
which begin by having a marginal efficiency at least equal to the rate
of interest, is increased, their marginal efficiency (for reasons,
sufficiently obvious, already given) tends to fall. Thus a point will
come at which it no longer pays to produce them, unless the rate of
interest falls pari passu. When there is no asset of which the marginal
efficiency reaches the rate of interest, the further production of
capital-assets will come to a standstill.
Let us suppose (as a mere hypothesis at this stage of the argument)
that there is some asset (eg. money) of which the rate of interest is
fixed (or declines more slowly as output increases than does any other
commodity's rate of interest); how is the position adjusted? Since a1 +
q1, a2 - c2 and l3, are necessarily equal, and since l3 by hypothesis
is either fixed or falling more slowly than q1 or -c2, it follows that
a1 and a2, must be rising. In other words, the present money-price of
every commodity other than money tends to fall relatively to its
expected future price. Hence, if q1 and -c2, continue to fall, a point
comes at which it is not profitable to produce any of the commodities,
unless the cost of production at some future date is expected to rise
above the present cost by an amount which will cover the cost of
carrying a stock produced now to the date of the prospective higher
price.
It is now apparent that our previous statement to the effect
that it is the money-rate of interest which sets a limit to the rate of
output, is not strictly correct. We should have said that it is that
asset's rate of interest which declines most slowly as the stock of
assets in general increases, which eventually knocks out the profitable
production of each of the others, ― except in the contingency, just
mentioned, of a special relationship between the present and
prospective costs of production. As output increases, own-rates of
interest decline to levels at which one asset after another falls below
the standard of profitable production; ― until, finally, one or more
own-rates of interest remain at a level which is above that of the
marginal efficiency of any asset whatever.
If by money we mean the standard of value, it is clear that it
is not necessarily the money-rate of interest which makes the trouble.
We could not get out of our difficulties (as some have supposed) merely
by decreeing that wheat or houses shall be the standard of value
instead of gold or sterling. For, it now appears that the same
difficulties will ensue if there continues to exist any asset of which
the own-rate of interest is reluctant to decline as output increases.
It may be, for example, that gold will continue to fill this role in a
country which has gone over to an inconvertible paper standard.
III
In attributing, therefore, a peculiar significance to the
money-rate of interest, we have been tacitly assuming that the kind of
money to which we are accustomed has some special characteristics which
lead to its own rate of interest in terms of itself as standard being
more reluctant to fall as output increases than the own-rates of
interest of any other assets in terms of themselves. Is this assumption
justified? Reflection shows, I think, that the following peculiarities,
which commonly characterise money as we know it, are capable of
justifying it. To the extent that the established standard of value has
these peculiarities, the summary statement, that it is the money-rate
of interest which is the significant rate of interest, will hold good.
(i) The first characteristic which tends towards the above conclusion
is the fact that money has, both in the long and in the short period, a
zero, or at any rate a very small, elasticity of production, so far as
the power of private enterprise is concerned, as distinct from the
monetary authority; ― elasticity of production[2] meaning, in this
context, the response of the quantity of labour applied to producing it
to a rise in the quantity of labour which a unit of it will command.
Money, that is to say, cannot be readily produced; ― labour cannot be
turned on at will by entrepreneurs to produce money in increasing
quantities as its price rises in terms of the wage-unit. In the case of
an inconvertible managed currency this condition is strictly satisfied.
But in the case of a gold-standard currency it is also approximately
so, in the sense that the maximum proportional addition to the quantity
of labour which can be thus employed is very small, except indeed in a
country of which gold-mining is the major industry.
Now, in the case of assets having an elasticity of production, the
reason why we assumed their own-rate of interest to decline was because
we assumed the stock of them to increase as the result of a higher rate
of output. In the case of money, however ― postponing, for the moment,
our consideration of the effects of reducing the wage-unit or of a
deliberate increase in its supply by the monetary authority ― the
supply is fixed. Thus the characteristic that money cannot be readily
produced by labour gives at once some prima facie presumption for the
view that its own-rate of interest will be relatively reluctant to
fall; whereas if money could be grown like a crop or manufactured like
a motor-car, depressions would be avoided or mitigated because, if the
price of other assets was tending to fall in terms of money, more
labour would be diverted into the production of money; ― as we see to
be the case in gold-mining countries, though for the world as a whole
the maximum diversion in this way is almost negligible.
(ii) Obviously, however, the above condition is satisfied, not only by
money, but by all pure rent-factors, the production of which is
completely inelastic. A second condition, therefore, is required to
distinguish money from other rent elements.
The second differentia of money is that it has an elasticity of
substitution equal, or nearly equal, to zero; which means that as the
exchange value of money rises there is no tendency to substitute some
other factor for it; ― except, perhaps, to some trifling extent, where
the money-commodity is also used in manufacture or the arts. This
follows from the peculiarity of money that its utility is solely
derived from its exchange-value, so that the two rise and fall pari
passu, with the result that as the exchange value of money rises there
is no motive or tendency, as in the case of rent-factors, to substitute
some other factor for it.
Thus, not only is it impossible to turn more labour on to producing
money when its labour-price rises, but money is a bottomless sink for
purchasing power, when the demand for it increases, since there is no
value for it at which demand is diverted ― as in the case of other
rent-factors ― so as to slop over into a demand for other things.
The only qualification to this arises when the rise in the value of
money leads to uncertainty as to the future maintenance of this rise;
in which event, a1 and a2 are increased, which is tantamount to an
increase in the commodity-rates of money-interest and is, therefore,
stimulating to the output of other assets.
(iii) Thirdly, we must consider whether these conclusions are upset by
the fact that, even though the quantity of money cannot be increased by
diverting labour into producing it, nevertheless an assumption that its
effective supply is rigidly fixed would be inaccurate. In particular, a
reduction of the wage-unit will release cash from its other uses for
the satisfaction of the liquidity-motive; whilst, in addition to this,
as money-values fall, the stock of money will bear a higher proportion
to the total wealth of the community.
It is not possible to dispute on purely theoretical grounds that
this reaction might be capable of allowing an adequate decline in the
money-rate of interest. There are, however, several reasons, which
taken in combination are of compelling force, why in an economy of the
type to which we are accustomed it is very probable that the money-rate
of interest will often prove reluctant to decline adequately:
(a) We have to allow, first of all, for the reactions of a fall in the
wage-unit on the marginal efficiencies of other assets in terms of
money; ― for it is the difference between these and the money-rate of
interest with which we are concerned. If the effect of the fall in the
wage-unit is to produce an expectation that it will subsequently rise
again, the result will be wholly favourable. If, on the contrary, the
effect is to produce an expectation of a further fall, the reaction on
the marginal efficiency of capital may offset the decline in the rate
of interest.[4]
(b) The fact that wages tend to be sticky in terms of money, the
money-wage being more stable than the real wage, tends to limit the
readiness of the wage-unit to fall in terms of money. Moreover, if this
were not so, the position might be worse rather than better; because,
if money-wages were to fall easily, this might often tend to create an
expectation of a further fall with unfavourable reactions on the
marginal efficiency of capital. Furthermore, if wages were to be fixed
in terms of some other commodity, eg. wheat, it is improbable that they
would continue to be sticky. It is because of money's other
characteristics ― those, especially, which make it liquid ― that wages,
when fixed in terms of it, tend to be sticky.[4]
(c) Thirdly, we come to what is the most fundamental consideration in
this context, namely, the characteristics of money which satisfy
liquidity-preference. For, in certain circumstances such as will often
occur, these will cause the rate of interest to be insensitive,
particularly below a certain figure,[5] even to a substantial increase
in the quantity of money in proportion to other forms of wealth. In
other words, beyond a certain point money's yield from liquidity does
not fall in response to an increase in its quantity to anything
approaching the extent to which the yield from other types of assets
falls when their quantity is comparably increased.
In this connection the low (or negligible) carrying-costs of
money play an essential part. For if its carrying-costs were material,
they would offset the effect of expectations as to the prospective
value of money at future dates. The readiness of the public to increase
their stock of money in response to a comparatively small stimulus is
due to the advantages of liquidity (real or supposed) having no offset
to contend with in the shape of carrying-costs mounting steeply with
the lapse of time. In the case of a commodity other than money a modest
stock of it may offer some convenience to users of the commodity. But
even though a larger stock might have some attractions as representing
a store of wealth of stable value, this would be offset by its
carrying-costs in the shape of storage, wastage, etc. Hence, after a
certain point is reached, there is necessarily a loss in holding a
greater stock.
In the case of money, however, this, as we have seen, is not so,
― and for a variety of reasons, namely, those which constitute money as
being, in the estimation of the public, par excellence “liquid.” Thus
those reformers, who look for a remedy by creating artificial
carrying-costs for money through the device of requiring legal-tender
currency to be periodically stamped at a prescribed cost in order to
retain its quality as money, or in analogous ways, have been on the
right track; and the practical value of their proposals deserves
consideration.
The significance of the money-rate of interest arises, therefore, out
of the combination of the characteristics that, through the working of
the liquidity-motive, this rate of interest may be somewhat
unresponsive to a change in the proportion which the quantity of money
bears to other forms of wealth measured in money, and that money has
(or may have) zero (or negligible) elasticities both of production and
of substitution. The first condition means that demand may be
predominantly directed to money, the second that when this occurs
labour cannot be employed in producing more money, and the third that
there is no mitigation at any point through some other factor being
capable, if it is sufficiently cheap, of doing money's duty equally
well. The only relief ― apart from changes in the marginal efficiency
of capital ― can come (so long as the propensity towards liquidity is
unchanged) from an increase in the quantity of money, or ― which is
formally the same thing ― a rise in the value of money which enables a
given quantity to provide increased money-services.
Thus a rise in the money-rate of interest retards the output of all the
objects of which the production is elastic without being capable of
stimulating the output of money (the production of which is, by
hypothesis, perfectly inelastic). The money-rate of interest, by
setting the pace for all the other commodity-rates of interest, holds
back investment in the production of these other commodities without
being capable of stimulating investment for the production of money,
which by hypothesis cannot be produced. Moreover, owing to the
elasticity of demand for liquid cash in terms of debts, a small change
in the conditions governing this demand may not much alter the
money-rate of interest, whilst (apart from official action) it is also
impracticable, owing to the inelasticity of the production of money,
for natural forces to bring the money-rate of interest down by
affecting the supply side. In the case of an ordinary commodity, the
inelasticity of the demand for liquid stocks of it would enable small
changes on the demand side to bring its rate of interest up or down
with a rush, whilst the elasticity of its supply would also tend to
prevent a high premium on spot over forward delivery. Thus with other
commodities left to themselves, “natural forces,” i.e. the ordinary
forces of the market, would tend to bring their rate of interest down
until the emergence of full employment had brought about for
commodities generally the inelasticity of supply which we have
postulated as a normal characteristic of money. Thus in the absence of
money and in the absence ― we must, of course, also suppose ― of any
other commodity with the assumed characteristics of money, the rates of
interest would only reach equilibrium when there is full employment.
Unemployment develops, that is to say, because people want the moon; ―
men cannot be employed when the object of desire (i.e. money) is
something which cannot be produced and the demand for which cannot be
readily choked off. There is no remedy but to persuade the public that
green cheese is practically the same thing and to have a green cheese
factory (i.e. a central bank) under public control.
It is interesting to notice that the characteristic which has
been traditionally supposed to render gold especially suitable for use
as the standard of value, namely, its inelasticity of supply, turns out
to be precisely the characteristic which is at the bottom of the
trouble.
Our conclusion can be stated in the most general form (taking the
propensity to consume as given) as follows. No further increase in the
rate of investment is possible when the greatest amongst the own-rates
of own-interest of all available assets is equal to the greatest
amongst the marginal efficiencies of all assets, measured in terms of
the asset whose own-rate of own-interest is greatest.
In a position of full employment this condition is necessarily
satisfied. But it may also be satisfied before full employment is
reached, if there exists some asset, having zero (or relatively small)
elasticities of production and substitution,[6] whose rate of interest
declines more slowly, as output increases, than the marginal
efficiencies of capital-assets measured in terms of it.
IV
We have shown above that for a commodity to be the standard of value is
not a sufficient condition for that commodity's rate of interest to be
the significant rate of interest. It is, however, interesting to
consider how far those characteristics of money as we know it, which
make the money-rate of interest the significant rate, are bound up with
money being the standard in which debts and wages are usually fixed.
The matter requires consideration under two aspects.
In the first place, the fact that contracts are fixed, and wages
are usually somewhat stable, in terms of money unquestionably plays a
large part in attracting to money so high a liquidity-premium. The
convenience of holding assets in the same standard as that in which
future liabilities may fall due and in a standard in terms of which the
future cost of living is expected to be relatively stable, is obvious.
At the same time the expectation of relative stability in the future
money-cost of output might not be entertained with much confidence（確信度）
ff the standard of value were a commodity with a high elasticity of
production. Moreover, the low carrying-costs of money as we know it
play quite as large a part as a high liquidity-premium in making the
money-rate of interest the significant rate. For what matters is the
difference between the liquidity-premium and the carrying-costs; and in
the case of most commodities, other than such assets as gold and silver
and bank-notes, the carrying-costs are at least as high as the
liquidity-premium ordinarily attaching to the standard in which
contracts and wages are fixed, so that, even if the liquidity-premium
now attaching to (e.g.) sterling-money were to be transferred to (eg.)
wheat, the wheat-rate of interest would still be unlikely to rise above
zero. It remains the case, therefore, that, whilst the fact of
contracts and wages being fixed in terms of money considerably enhances
the significance of the money-rate of interest, this circumstance is,
nevertheless, probably insufficient by itself to produce the observed
characteristics of the money-rate of interest.
The second point to be considered is more subtle. The normal
expectation that the value of output will be more stable in terms of
money than in terms of any other commodity, depends of course, not on
wages being arranged in terms of money, but on wages being relatively
sticky in terms of money. What, then, would the position be if wages
were expected to be more sticky (i.e. more stable) in terms of some one
or more commodities other than money, than in terms of money itself?
Such an expectation requires, not only that the costs of the commodity
in question are expected to be relatively constant in terms of the
wage-unit for a greater or smaller scale of output both in the short
and in the long period, but also that any surplus over the current
demand at cost-price can be taken into stock without cost, i.e. that
its liquidity-premium exceeds its carrying-costs (for, otherwise, since
there is no hope of profit from a higher price, the carrying of a stock
must necessarily involve a loss). If a commodity can be found to
satisfy these conditions, then, assuredly, it might be set up as a
rival to money. Thus it is not logically impossible that there should
be a commodity in terms of which the value of output is expected to be
more stable than in terms of money. But it does not seem probable that
any such commodity exists.
I conclude, therefore, that the commodity, in terms of which
wages are expected to be most sticky, cannot be one whose elasticity of
production is not least, and for which the excess of carrying-costs
over liquidity-premium is not least. In other words, the expectation of
a relative stickiness of wages in terms of money is a corollary of the
excess of liquidity-premium over carrying-costs being greater for money
than for any other asset.
Thus we see that the various characteristics, which combine to make the
money-rate of interest significant, interact with one another in a
cumulative fashion. The fact that money has low elasticities of
production and substitution and low carrying-costs tends to raise the
expectation that will be relatively stable; and this expectation
enhances money's liquidity-premium and prevents the exceptional
correlation between the money-rate of interest and the marginal
efficiencies of other assets which might, if it could exist, rob the
money-rate of interest of its sting.
Professor Pigou (with others) has been accustomed to assume that there
is a presumption in favour of real wages being more stable than
money-wages. But this could only be the case if there were a
presumption in favour of stability of employment. Moreover, there is
also the difficulty that wage-goods have a high carrying-cost. If,
indeed, some attempt were made to stabilise real wages by fixing wages
in terms of wage-goods, the effect could only be to cause a violent
oscillation of money-prices. For every small fluctuation in the
propensity to consume and the inducement to invest would cause
money-prices to rush violently between zero and infinity. That
money-wages should be more stable than real wages is a condition of the
system possessing inherent stability.
Thus the attribution of relative stability to real wages is not merely
a mistake in fact and experience. It is also a mistake in logic, if we
are supposing that the system in view is stable, in the sense that
small changes in the propensity to consume and the inducement to invest
do not produce violent effects on prices.
V
As a footnote to the above, it may be worth emphasising what has been
already stated above, namely, that “liquidity” and “carrying-costs” are
both a matter of degree; and that it is only in having the former high
relatively to the latter that the peculiarity of “money” consists.
Consider, for example, an economy in which there is no asset for which
the liquidity-premium is always in excess of the carrying-costs; which
is the best definition I can give of a so-called “non-monetary”
economy. There exists nothing, that is to say, but particular
consumables and particular capital equipments more or less
differentiated according to the character of the consumables which they
can yield up, or assist to yield up, over a greater or a shorter period
of time; all of which, unlike cash, deteriorate or involve expense, if
they are kept in stock, to a value in excess of any liquidity-premium
which may attach to them.
In such an economy capital equipments will differ from one
another (a) in the variety of the consumables in the production of
which they are capable of assisting, (b) in the stability of value of
their output (in the sense in which the value of bread is more stable
through time than the value of fashionable novelties), and (c) in the
rapidity with which the wealth embodied in them can become “liquid”, in
the sense of producing output, the proceeds of which can be re-embodied
if desired in quite a different form.
The owners of wealth will then weigh the lack of “liquidity” of
different capital equipments in the above sense as a medium in which to
hold wealth against the best available actuarial estimate of their
prospective yields after allowing for risk. The liquidity-premium, it
will be observed, is partly similar to the risk-premium, but partly
different; ― the difference corresponding to the difference between the
best estimates we can make of probabilities and the confidence with
which we make them.[7] When we were dealing, in earlier chapters, with
the estimation of prospective yield, we did not enter into detail as to
how the estimation is made: and to avoid complicating the argument, we
did not distinguish differences in liquidity from differences in risk
proper. It is evident, however, that in calculating the own-rate of
interest we must allow for both.
There is, clearly, no absolute standard of “liquidity” but
merely a scale of liquidity ― a varying premium of which account has to
be taken, in addition to the yield of use and the carrying-costs, in
estimating the comparative attractions of holding different forms of
wealth. The conception of what contributes to “liquidity” is a partly
vague one, changing from time to time and depending on social practices
and institutions. The order of preference in the minds of owners of
wealth in which at any given time they express their feelings about
liquidity is, however, definite and is all we require for our analysis
of the behaviour of the economic system.
It may be that in certain historic environments the possession
of land has been characterised by a high liquidity-premium in the minds
of owners of wealth; and since land resembles money in that its
elasticities of production and substitution may be very low,[8] it is
conceivable that there have been occasions in history in which the
desire to hold land has played the same role in keeping up the rate of
interest at too high a level which money has played in recent times. It
is difficult to trace this influence quantitatively owing to the
absence of a forward price for land in terms of itself which is
strictly comparable with the rate of interest on a money debt. We have,
however, something which has, at times, been closely analogous, in the
shape of high rates of interest on mortgages.[9] The high rates of
interest from mortgages on land, often exceeding the probable net yield
from cultivating the land, have been a familiar feature of many
agricultural economies. Usury laws have been directed primarily against
encumbrances of this character. And rightly so. For in earlier social
organisations where long-term bonds in the modern sense were
non-existent, the competition of a high interest-rate on mortgages may
well have had the same effect in retarding the growth of wealth from
current investment in newly produced capital-assets, as high interest
rates on long-term debts have had in more recent times.
That the world after several millennia of steady individual
saving, is so poor as it is in accumulated capital-assets, is to be
explained, in my opinion, neither by the improvident propensities of
mankind, nor even by the destruction of war, but by the high
liquidity-premiums formerly attaching to the ownership of land and now
attaching to money. I differ in this from the older view as expressed
by Marshall with an unusual dogmatic force in his Principles of
Economics, p. 581: ―
Everyone is aware that the accumulation of wealth is held in
check, and the rate of interest so far sustained, by the preference
which the great mass of humanity have for present over deferred
gratifications, or, in other words, by their unwillingness to “wait”.
VI
In my Treatise on Money I defined what purported to be a unique
rate of interest, which I called the natural rate of interest ― namely,
the rate of interest which, in the terminology of my Treatise,
preserved equality between the rate of saving (as there defined) and
the rate of investment. I believed this to be a development and
clarification of Wicksell's “natural rate of interest”, which was,
according to him, the rate which would preserve the stability of some,
not quite clearly specified, price-level.
I had, however, overlooked the fact that in any given society
there is, on this definition, a different natural rate of interest for
each hypothetical level of employment. And, similarly, for every rate
of interest there is a level of employment for which that rate is the
“natural” rate, in the sense that the system will be in equilibrium
with that rate of interest and that level of employment. Thus it was a
mistake to speak of the natural rate of interest or to suggest that the
above definition would yield a unique value for the rate of interest
irrespective of the level of employment. I had not then understood
that, in certain conditions, the system could be in equilibrium with
less than full employment.
I am now no longer of the opinion that the concept of a
“natural” rate of interest, which previously seemed to me a most
promising idea, has anything very useful or significant to contribute
to our analysis. It is merely the rate of interest which will preserve
the status quo; and, in general, we have no predominant interest in the
status quo as such.
If there is any such rate of interest, which is unique and
significant, it must be the rate which we might term the neutral rate
of interest,[10] namely, the natural rate in the above sense which is
consistent with full employment, given the other parameters of the
system; though this rate might be better described, perhaps, as the
optimum rate.
The neutral rate of interest can be more strictly defined as the
rate of interest which prevails in equilibrium when output and
employment are such that the elasticity of employment as a whole is
zero.[11]
The above gives us, once again, the answer to the question as to
what tacit assumption is required to make sense of the classical theory
of the rate of interest. This theory assumes either that the actual
rate of interest is always equal to the neutral rate of interest in the
sense in which we have just defined the latter, or alternatively that
the actual rate of interest is always equal to the rate of interest
which will maintain employment at some specified constant level. If the
traditional theory is thus interpreted, there is little or nothing in
its practical conclusions to which we need take exception. The
classical theory assumes that the banking authority or natural forces
cause the market-rate of interest to satisfy one or other of the above
conditions; and it investigates what laws will govern the application
and rewards of the community's productive resources subject to this
assumption. With this limitation in force, the volume of output depends
solely on the assumed constant level of employment in conjunction with
the current equipment and technique; and we are safely ensconced in a
Ricardian world.
Author's Footnotes
[1]. This relationship was first pointed out by Mr. Sraffa, Economic Journal, March 1932, p. 50.
[2]. See Chapter 20.
[3]. This is a matter which will be examined in greater detail in Chapter 19 below.
[4]. If wages (and contracts) were fixed in terms of wheat, it might be
that wheat would acquire some of money's liquidity-premium; ― we will
return to this question in (IV) below.
[5]. See p. 172 above.
[6]. A zero elasticity is a more stringent condition than is necessarily required.
[7]. Cf. the footnote to p. 148 above.
[8]. The attribute of “liquidity” is by no means independent of the
presence of these two characteristics. For it is unlikely that an
asset, of which the supply can be easily increased or the desire for
which can be easily diverted by a change in relative price, will
possess the attribute of “liquidity” in the minds of owners of wealth.
Money itself rapidly loses the attribute of “liquidity” if its future
supply is expected to undergo sharp changes.
[9]. A mortgage and the interest thereon are, indeed, fixed in terms of
money. But the fact that the mortgagor has the option to deliver the
land itself in discharge of the debt ― and must so deliver it if he
cannot find the money on demand ― has sometimes made the mortgage
system approximate to a contract of land for future delivery against
land for spot delivery. There have been sales of lands to tenants
against mortgages effected by them, which, in fact, came very near to
being transactions of this character.
[10]. This definition does not correspond to any of the various
definitions of neutral money given by recent writers; though it may,
perhaps, have some relation to the objective which these writers have
had in mind.
[11]. Cf. Chapter 20 below.
Chapter 18. The General Theory of Employment Re-Stated
I
WE have now reached a point where we can gather together the threads of
our argument. To begin with, it may be useful to make clear which
elements in the economic system we usually take as given, which are the
independent variables of our system and which are the dependent
variables.
We take as given the existing skill and quantity of available labour,
the existing quality and quantity of available equipment, the existing
technique, the degree of competition, the tastes and habits of the
consumer, the disutility of different intensifies of labour and of the
activities of supervision and organisation, as well as the social
structure including the forces, other than our variables set forth
below, which determine the distribution of the national income. This
does not mean that we assume these factors to be constant; but merely
that, in this place and context, we are not considering or taking into
account the effects and consequences of changes in them.
Our independent variables are, in the first instance, the propensity to
consume, the schedule of the marginal efficiency of capital and the
rate of interest, though, as we have already seen, these are capable of
further analysis.
Our dependent variables are the volume of employment and the national income (or national dividend) measured in wage-units.
The factors, which we have taken as given, influence our independent
variables, but do not completely determine them. For example, the
schedule of the marginal efficiency of capital depends partly on the
existing quantity of equipment which is one of the given factors, but
partly on the state of long-term expectation which cannot be inferred
from the given factors. But there are certain other elements which the
given factors determine so completely that we can treat these
derivatives as being themselves given. For example, the given factors
allow us to infer what level of national income measured in terms of
the wage-unit will correspond to any given level of employment; so
that, within the economic framework which we take as given, the
national income depends on the volume of employment, i.e. on the
quantity of effort currently devoted to production, in the sense that
there is a unique correlation between the two.[1] Furthermore, they
allow us to infer the shape of the aggregate supply functions, which
embody the physical conditions of supply, for different types of
products; ― that is to say, the quantity of employment which will be
devoted to production corresponding to any given level of effective
demand measured in terms of wage-units. Finally, they furnish us with
the supply function of labour (or effort); so that they tell us inter
alia at what point the employment function[2] for labour as a whole
will cease to be elastic.
The schedule of the marginal efficiency of capital depends, however,
partly on the given factors and partly on the prospective yield of
capital-assets of different kinds; whilst the rate of interest depends
partly on the state of liquidity-preference (i.e. on the liquidity
function) and partly on the quantity of money measured in terms of
wage-units. Thus we can sometimes regard our ultimate independent
variables as consisting of (1) the three fundamental psychological
factors, namely, the psychological propensity to consume, the
psychological attitude to liquidity and the psychological expectation
of future yield from capital-assets, (2) the wage-unit as determined by
the bargains reached between employers and employed, and (3) the
quantity of money as determined by the action of the central bank; so
that, if we take as given the factors specified above, these variables
determine the national income (or dividend) and the quantity of
employment. But these again would be capable of being subjected to
further analysis, and are not, so to speak, our ultimate atomic
independent elements.
The division of the determinants of the economic system into the two
groups of given factors and independent variables is, of course, quite
arbitrary from any absolute standpoint. The division must be made
entirely on the basis of experience, so as to correspond on the one
hand to the factors in which the changes seem to be so slow or so
little relevant as to have only a small and comparatively negligible
short-term influence on our quaesitum; and on the other hand to those
factors in which the changes are found in practice to exercise a
dominant influence on our quaesitum. Our present object is to discover
what determines at any time the national income of a given economic
system and (which is almost the same thing) the amount of its
employment; which means in a study so complex as economics, in which we
cannot hope to make completely accurate generalisations, the factors
whose changes mainly determine our quaesitum. Our final task might be
to select those variables which can be deliberately controlled or
managed by central authority in the kind of system in which we actually
live.
II
Let us now attempt to summarise the argument of the previous chapters;
taking the factors in the reverse order to that in which we have
introduced them.
There will be an inducement to push the rate of new investment to the
point which forces the supply-price of each type of capital-asset to a
figure which, taken in conjunction with its prospective yield, brings
the marginal efficiency of capital in general to approximate equality
with the rate of interest. That is to say, the physical conditions of
supply in the capital-goods industries, the state of confidence
concerning the prospective yield, the psychological attitude to
liquidity and the quantity of money (preferably calculated in terms of
wage-units) determine, between them, the rate of new investment.
But an increase (or decrease) in the rate of investment will have to
carry with it an increase (or decrease) in the rate of consumption;
because the behaviour of the public is, in general, of such a character
that they are only willing to widen (or narrow) the gap between their
income and their consumption if their income is being increased (or
diminished). That is to say, changes in the rate of consumption are, in
general, in the same direction (though smaller in amount) as changes in
the rate of income. The relation between the increment of consumption
which has to accompany a given increment of saving is given by the
marginal propensity to consume. The ratio, thus determined, between an
increment of investment and the corresponding increment of aggregate
income, both measured in wage-units, is given by the investment
multiplier.
Finally, if we assume (as a first approximation) that the employment
multiplier is equal to the investment multiplier, we can, by applying
the multiplier to the increment (or decrement) in the rate of
investment brought about by the factors first described, infer the
increment of employment.
An increment (or decrement) of employment is liable, however, to raise
(or lower) the schedule of liquidity-preference; there being three ways
in which it will tend to increase the demand for money, inasmuch as the
value of output will rise when employment increases even if the
wage-unit and prices (in terms of the wage-unit) are unchanged, but, in
addition, the wage-unit itself will tend to rise as employment
improves, and the increase in output will be accompanied by a rise of
prices (in terms of the wage-unit) owing to increasing cost in the
short period.
Thus the position of equilibrium will be influenced by these
repercussions; and there are other repercussions also. Moreover, there
is not one of the above factors which is not liable to change without
much warning, and sometimes substantially. Hence the extreme complexity
of the actual course of events. Nevertheless, these seem to be the
factors which it is useful and convenient to isolate. If we examine any
actual problem along the lines of the above schematism, we shall find
it more manageable; and our practical intuition (which can take account
of a more detailed complex of facts than can be treated on general
principles) will be offered a less intractable material upon which to
work.
III
The above is a summary of the General Theory. But the actual phenomena
of the economic system are also coloured by certain special
characteristics of the propensity to consume, the schedule of the
marginal efficiency of capital and the rate of interest, about which we
can safely generalise from experience, but which are not logically
necessary.
In particular, it is an outstanding characteristic of the
economic system in which we live that, whilst it is subject to severe
fluctuations in respect of output and employment, it is not violently
unstable. Indeed it seems capable of remaining in a chronic condition
of sub-normal activity for a considerable period without any marked
tendency either towards recovery or towards complete collapse.
（回復へも崩壊へも明確に進むことがない）Moreover, the evidence indicates that full, or even
approximately full, employment is of rare and short-lived occurrence.
Fluctuations may start briskly but seem to wear themselves out before
they have proceeded to great extremes, and an intermediate situation
which is neither desperate nor satisfactory is our normal lot. It is
upon the fact that fluctuations tend to wear themselves out before
proceeding to extremes and eventually to reverse themselves, that the
theory of business cycles having a regular phase has been founded. The
same thing is true of prices, which, in response to an initiating cause
of disturbance, seem to be able to find a level at which they can
remain, for the time being, moderately stable.
Now, since these facts of experience do not follow of logical
necessity, one must suppose that the environment and the psychological
propensities of the modern world must be of such a character as to
produce these results. It is, therefore, useful to consider what
hypothetical psychological propensities would lead to a stable system;
and, then, whether these propensities can be plausibly ascribed, on our
general knowledge of contemporary human nature, to the world in which
we live.
The conditions of stability which the foregoing analysis suggests to us
as capable of explaining the observed results are the following:
(i) The marginal propensity to consume is such that, when the output of
a given community increases (or decreases) because more (or less)
employment is being applied to its capital equipment, the multiplier
relating the two is greater than unity but not very large.
(ii) When there is a change in the prospective yield of capital or in
the rate of interest, the schedule of the marginal efficiency of
capital will be such that the change in new investment will not be in
great disproportion to the change in the former ; i.e. moderate changes
in the prospective yield of capital or in the rate of interest will not
be associated with very great changes in the rate of investment.
(iii) When there is a change in employment, money-wages tend to change
in the same direction as, but not in great disproportion to, the change
in employment; i.e. moderate changes in employment are not associated
with very great chances in money-wages. This is a condition of the
stability of prices rather than of employment.
(iv) We may add a fourth condition, which provides not so much for the
stability of the system as for the tendency of a fluctuation in one
direction to reverse itself in due course; namely, that a rate of
investment, higher (or lower) than prevailed formerly, begins to react
unfavourably (or favourably) on the marginal efficiency of capital if
it is continued for a period which, measured in years, is not very
large.
(i) Our first condition of stability, namely, that the multiplier,
whilst greater than unity, is not very great, is highly plausible as a
psychological characteristic of human nature. As real income increases,
both the pressure of present needs diminishes and the margin over the
established standard of life is increased; and as real income
diminishes the opposite is true. Thus it is natural ― at any rate on
the average of the community ― that current consumption should be
expanded when employment increases) but by less than the full increment
of real income; and that it should be diminished when employment
diminishes, but by less than the full decrement of real income.
Moreover, what is true of the average of individuals is likely to be
also true of governments especially in an age when a progressive
increase of unemployment will usually force the State to provide relief
out of borrowed funds.
But whether or not this psychological law strikes the reader as
plausible a priori, it is certain that experience would be extremely
different from what it is if the law did not hold. For in that case an
increase of investment, however small, would set moving a cumulative
increase of effective demand until a position of full employment had
been reached; while a decrease of investment would set moving a
cumulative decrease of effective demand until no one at all was
employed. Yet experience shows that we are generally in an intermediate
position. It is not impossible that there may be a range within which
instability does in fact prevail. But, if so, it is probably a narrow
one, outside of which in either direction our psychological law must
unquestionably hold good. Furthermore, it is also evident that the
multiplier, though exceeding unity, is not, in normal circumstances,
enormously large. For, if it were, a given change in the rate of
investment would involve a great change (limited only by full or zero
employment) in the rate of consumption.
(ii) Whilst our first condition provides that a moderate change in the
rate of investment will not involve an indefinitely great change in the
demand for consumption-goods our second condition provides that a
moderate change in the prospective yield of capital-assets or in the
rate of interest will not involve an indefinitely great change in the
rate of investment. This is likely to be the case owing to the
increasing cost of producing a greatly enlarged output from the
existing equipment. If, indeed, we start from a position where there
are very large surplus resources for the production of capital-assets,
there may be considerable instability within a certain range; but this
will cease to hold good as soon as the surplus is being largely
utilised. Moreover, this condition sets a limit to the instability
resulting from rapid changes in the prospective yield of capital-assets
due to sharp fluctuations in business psychology or to epoch-making
inventions ― though more, perhaps, in the upward than in the downward
direction.
(iii) Our third condition accords with our experience of human nature.
For although the struggle for money-wages is, as we have pointed out
above, essentially a struggle to maintain a high relative wage, this
struggle is likely, as employment increases, to be intensified in each
individual case both because the bargaining position of the worker is
improved and because the diminished marginal utility of his wage and
his improved financial margin make him readier to run risks. Yet, all
the same, these motives will operate within limits, and workers will
not seek a much greater money-wage when employment improves or allow a
very great reduction rather than suffer any unemployment at all.
But here again, whether or not this conclusion is plausible a priori,
experience shows that some such psychological law must actually hold.
For if competition between unemployed workers always led to a very
great reduction of the money-wage, there would be a violent instability
in the price-level. Moreover, there might be no position of stable
equilibrium except in conditions consistent with full employment; since
the wage-unit might have to fall without limit until it reached a point
where the effect of the abundance of money in terms of the wage-unit on
the rate of interest was sufficient to restore a level of full
employment. At no other point could there be a resting-place.[3]
(iv) Our fourth condition, which is a condition not so much of
stability as of alternate recession and recovery, is merely based on
the presumption that capital-assets are of various ages, wear out with
time and are not all very long-lived; so that if the rate of investment
falls below a certain minimum level, it is merely a question of time
(failing large fluctuations in other factors) before the marginal
efficiency of capital rises sufficiently to bring about a recovery of
investment above this minimum. And similarly, of course, if investment
rises to a higher figure than formerly, it is only a question of time
before the marginal efficiency of capital falls sufficiently to bring
about a recession unless there are compensating changes in other
factors.
For this reason, even those degrees of recovery and recession, which
can occur within the limitations set by our other conditions of
stability, will be likely, if they persist for a sufficient length of
time and are not interfered with by changes in the other factors, to
cause a reverse movement in the opposite direction, until the same
forces as before again reverse the direction.
Thus our four conditions together are adequate to explain the
outstanding features of our actual experience; ― namely, that we
oscillate, avoiding the gravest extremes of fluctuation in employment
and in prices in both directions, round an intermediate position
appreciably below full employment and appreciably above the minimum
employment a decline below which would endanger life.
But we must not conclude that the mean position thus determined by
“natural” tendencies, namely, by those tendencies which are likely to
persist, failing measures expressly designed to correct them, is,
therefore, established by laws of necessity. The unimpeded rule of the
above conditions is a fact of observation concerning the world as it is
or has been, and not a necessary principle which cannot be changed.
Author's Footnotes
[1]. We are ignoring at this stage certain complications which arise
when the employment functions of different products have different
curvatures within the relevant range of employment. See Chapter 20
below.
[2]. Defined in Chapter 20 below.
[3]. The effects of changes in the wage-unit will be considered in detail in Chapter 19.
Book V Money-Wages and Prices
Chapter 19. Changes in Money-Wages
I
IT would have been an advantage if the effects of a change in
money-wages could have been discussed in an earlier chapter. For the
Classical Theory has been accustomed to rest the supposedly
self-adjusting character of the economic system on an assumed fluidity
of money-wages; and, when there is rigidity, to lay on this rigidity
the blame of maladjustment.
It was not possible, however, to discuss this matter fully until
our own theory had been developed. For the consequences of a change in
money-wages are complicated. A reduction in money-wages is quite
capable in certain circumstances of affording a stimulus to output, as
the classical theory supposes. My difference from this theory is
primarily a difference of analysis; so that it could not be set forth
clearly until the reader was acquainted with my own method.
The generally accepted explanation is, as I understand it, quite a
simple one. It does not depend on roundabout repercussions, such as we
shall discuss below. The argument simply is that a reduction in
money-wages will cet. par. stimulate demand by diminishing the price of
the finished product, and will therefore increase output and employment
up to the point where the reduction which labour has agreed to accept
in its money-wages is just offset by the diminishing marginal
efficiency of labour as output (from a given equipment) is increased.
In its crudest form, this is tantamount to assuming that the
reduction in money-wages will leave demand unaffected. There may be
some economists who would maintain that there is no reason why demand
should be affected, arguing that aggregate demand depends on the
quantity of money multiplied by the income-velocity of money and that
there is no obvious reason why a reduction in money-wages would reduce
either the quantity of money or its income-velocity. Or they may even
argue that profits will necessarily go up because wages have gone down.
But it would, I think, be more usual to degree that the reduction in
money-wages may have some effect on aggregate demand through its
reducing the purchasing power of some of the workers, but that the real
demand of other factors, whose money incomes have not been reduced,
will be stimulated by the fall in prices, and that the aggregate demand
of the workers themselves will be very likely increased as a result of
the increased volume of employment, unless the elasticity of demand for
labour in response to changes in money-wages is less than unity. Thus
in the new equilibrium there will be more employment than there would
have been otherwise except, perhaps, in some unusual limiting case
which has no reality in practice.
It is from this type of analysis that I fundamentally differ; or
rather from the analysis which seems to lie behind such observations as
the above. For whilst the above fairly represents, I think, the way in
which many economists talk and write, the underlying analysis has
seldom been written down in detail.
It appears, however, that this way of thinking is probably
reached as follows. In any given industry we have a demand schedule for
the product relating the quantities which can be sold to the prices
asked; we have a series of supply schedules relating the prices which
will be asked for the sale of different quantities on various bases of
cost; and these schedules between them lead up to a further schedule
which, on the assumption that other costs are unchanged (except as a
result of the change in output), gives us the demand schedule for
labour in the industry relating the quantity of employment to different
levels of wages, the shape of the curve at any point furnishing the
elasticity of demand for labour. This conception is then transferred
without substantial modification to industry as a whole; and it is
supposed, by a parity of reasoning, that we have a demand schedule for
labour in industry as a whole relating the quantity of employment to
different levels of wages. It is held that it makes no material
difference to this argument whether it is in terms of money-wages or of
real wages. If we are thinking in terms of money-wages, we must, of
course, correct for changes in the value of money; but this leaves the
general tendency of the argument unchanged, since prices certainly do
not change in exact proportion to changes in money-wages.
If this is the groundwork of the argument (and, if it is not, I
do not know what the groundwork is), surely it is fallacious. For the
demand schedules for particular industries can only be constructed on
some fixed assumption as to the nature of the demand and supply
schedules of other industries and as to the amount of the aggregate
effective demand. It is invalid, therefore, to transfer the argument to
industry as a whole unless we also transfer our assumption that the
aggregate effective demand is fixed. Yet this assumption reduces the
argument to an ignoratio elenchi. For, whilst no one would wish to deny
the proposition that a reduction in money-wages accompanied by the same
ggregate effective demand as before will be associated with an increase
in employment, the precise question at issue is whether the reduction
in money-wages will or will not be accompanied by the same aggregate
effective demand as before measured in money, or, at any rate, by an
aggregate effective demand which is not reduced in full proportion to
the reduction in money-wages (i.e. which is somewhat greater measured
in wage-units). But if the classical theory is not allowed to extend by
analogy its conclusions in respect of a particular industry to industry
as a whole, it is wholly unable to answer the question what effect on
employment a reduction in money-wages will have. For it has no method
of analysis wherewith to tackle the problem. Professor Pigou's Theory
of Unemployment seems to me to get out of the Classical Theory all that
can be got out of it; with the result that the book becomes a striking
demonstration that this theory has nothing to offer, when it is applied
to the problem of what determines the volume of actual employment as a
whole.[1]
II
Let us, then, apply our own method of analysis to answering the
problem. It falls into two parts. (1) Does a reduction in money-wages
have a direct tendency, cet. par., to increase employment, “cet. par.”
being taken to mean that the propensity to consume, the schedule of the
marginal efficiency of capital and the rate of interest are the same as
before for the community as a whole? And (2) does a reduction in
money-wages have a certain or probable tendency to affect employment in
a particular direction through its certain or probable repercussions on
these three factors?
The first question we have already answered in the negative in the
preceding chapters. For we have shown that the volume of employment is
uniquely correlated with the volume of effective demand measured in
wage-units, and that the effective demand, being the sum of the
expected consumption and the expected investment, cannot change, if the
propensity to consume, the schedule of marginal efficiency of capital
and the rate of interest are all unchanged. If, without any change in
these factors（これらの要素に変化がない場合には）, the entrepreneurs were to increase
employment as a whole, their proceeds will necessarily fall short of
their supply-price.
Perhaps it will help to rebut the crude conclusion that a reduction in
money-wages will increase employment “because it reduces the cost of
production”, if we follow up the course of events on the hypothesis
most favourable to this view, namely that at the outset entrepreneurs
expect the reduction in money-wages to have this effect. It is indeed
not unlikely that the individual entrepreneur, seeing his own costs
reduced, will overlook at the outset the repercussions on the demand
for his product and will act on the assumption that he will be able to
sell at a profit a larger output than before. If, then, entrepreneurs
generally act on this expectation, will they in fact succeed in
increasing their profits? Only if the community's marginal propensity
to consume is equal to unity, so that there is no gap between the
increment of income and the increment of consumption; or if there is an
increase in investment, corresponding to the gap between the increment
of income and the increment of consumption, which will only occur if
the schedule of marginal efficiencies of capital has increased
relatively to the rate of interest. Thus the proceeds realised from the
increased output will disappoint the entrepreneurs and employment will
fall back again to its previous figure, unless the marginal propensity
to consume is equal to unity or the reduction in money-wages has had
the effect of increasing the schedule of marginal efficiencies of
capital relatively to the rate of interest and hence the amount of
investment. For if entrepreneurs offer employment on a scale which, if
they could sell their output at the expected price, would provide the
public with incomes out of which they would save more than the amount
of current investment, entrepreneurs are bound to make a loss equal to
the difference; and this will be the case absolutely irrespective of
the level of money wages. At the best, the date of their disappointment
can only be delayed for the interval during which their own investment
in increased working capital is filling the gap.
Thus the reduction in money-wages will have no lasting tendency to
increase employment except by virtue of its repercussions either on the
propensity to consume for the community as a whole, or on the schedule
of marginal efficiencies of capital, or on the rate of interest. There
is no method of analysing the effect of a reduction in money-wages,
except by following up its possible effects on these three factors.
The most important repercussions on these factors are likely, in practice, to be the following:
(1) A reduction of money-wages will somewhat reduce prices. It will,
therefore, involve some redistribution of real income (a) from
wage-earners to other factors entering into marginal prime-cost whose
remuneration has not been reduced, and (b) from entrepreneurs to
rentiers to whom a certain income fixed in terms of money has been
guaranteed.
What will be the effect of this redistribution on the propensity to
consume for the community as a whole? The transfer from wage-earners to
other factors is likely to diminish the propensity to consume. The
effect of the transfer from entrepreneurs to rentiers is more open to
doubt. But if rentiers represent on the whole the richer section of the
community and those whose standard of life is least flexible, then the
effect of this also will be unfavourable. What the net result will be
on a balance of considerations, we can only guess. Probably it is more
likely to be adverse than favourable.
(2) If we are dealing with an unclosed system, and the reduction of
money-wages is a reduction relatively to money-wages abroad when both
are reduced to a common unit, it is evident that the change will be
favourable to investment, since it will tend to increase the balance of
trade. This assumes, of course, that the advantage is not offset by a
change in tariffs, quotas, etc. The greater strength of the traditional
belief in the efficacy of a reduction in money-wages as a means of
increasing employment in Great Britain, as compared with the United
States, is probably attributable to the latter being, comparatively
with ourselves, a closed system.
(3) In the case of an unclosed system, a reduction of money-wages,
though it increases the favourable balance of trade, is likely to
worsen the terms of trade. Thus there will be a reduction in real
incomes, except in the case of the newly employed, which may tend to
increase the propensity to consume.
(4) If the reduction of money-wages is expected to be a reduction
relatively to money-wages in the future, the change will be favourable
to investment, because as we have seen above, it will increase the
marginal efficiency of capital; whilst for the same reason it may be
favourable to consumption. If, on the other hand, the reduction leads
to the expectation, or even to the serious possibility, of a further
wage-reduction in prospect, it will have precisely the opposite effect.
For it will diminish the marginal efficiency of capital and will lead
to the postponement both of investment and of consumption.
(5) The reduction in the wages-bill, accompanied by some reduction in
prices and in money-incomes generally, will diminish the need for cash
for income and business purposes; and it will therefore reduce pro
tanto the schedule of liquidity-preference for the community as a
whole. Cet. par. this will reduce the rate of interest and thus prove
favourable to investment. In this case, however, the effect of
expectation concerning the future will be of an opposite tendency to
those just considered under (4). For, if wages and prices are expected
to rise again later on, the favourable reaction will be much less
pronounced in the case of long-term loans than in that of short-term
loans. If, moreover, the reduction in wages disturbs political
confidence by causing popular discontent, the increase in
Liquidity-preference due to this cause may more than offset the release
of cash from the active circulation.
(6) Since a special reduction of money-wages is always advantageous to
an individual entrepreneur or industry, a general reduction (though its
actual effects are different) may also produce an optimistic tone in
the minds of entrepreneurs, which may break through a vicious circle of
unduly pessimistic estimates of the marginal efficiency of capital and
set things moving again on a more normal basis of expectation. On the
other hand, if the workers make the same mistake as their employers
about the effects of a general reduction, labour troubles may offset
this favourable factor; apart from which, since there is, as a rule, no
means of securing a simultaneous and equal reduction of money-wages in
all industries, it is in the interest of all workers to resist a
reduction in their own particular case. In fact, a movement by
employers to revise money-wage bargains downward will be much more
strongly resisted than a gradual and automatic lowering of real wages
as a result of rising prices.
(7) On the other hand, the depressing influence on entrepreneurs of
their greater burden of debt may partly offset any cheerful reactions
from the reduction of wages. Indeed if the fall of wages and prices
goes far, the embarrassment of those entrepreneurs who are heavily
indebted may soon reach the point of insolvency, ― with severely
adverse effects on investment. Moreover the effect of the lower
price-level on the real burden of the National Debt and hence on
taxation is likely to prove very adverse to business confidence.
This is not a complete catalogue of all the possible reactions of wage
reductions in the complex real world. But the above cover, I think,
those which are usually the most important.
If, therefore, we restrict our argument to the case of a closed
system, and assume that there is nothing to be hoped, but if anything
the contrary, from the repercussions of the new distribution of real
incomes on the community's propensity to spend, it follows that we must
base any hopes of favourable results to employment from a reduction in
money-wages mainly on an improvement in investment due either to an
increased marginal efficiency of capital under (4) or a decreased rate
of interest under (5). Let us consider these two possibilities in
further detail.
The contingency, which is favourable to an increase in the marginal
efficiency of capital, is that in which money-wages are believed to
have touched bottom, so that further changes are expected to be in the
upward direction. The most unfavourable contingency is that in which
money-wages are slowly sagging downwards and each reduction in wages
serves to diminish confidence in the prospective maintenance of wages.
When we enter on a period of weakening effective demand, a sudden large
reduction of money-wages to a level so low that no one believes in its
indefinite continuance would be the event most favourable to a
strengthening of effective demand. But this could only be accomplished
by administrative decree and is scarcely practical politics under a
system of free wage-bargaining. On the other hand, it would be much
better that wages should be rigidly fixed and deemed incapable of
material changes, than that depressions should be accompanied by a
gradual downward tendency of money-wages, a further moderate wage
reduction being expected to signalize（はっきり示す） each increase of, say, 1
per cent. in the amount of unemployment. For example, the effect of an
expectation that wages are going to sag by, say, 2 per cent. in the
coming year will be roughly equivalent to the effect of a rise of 2 per
cent. in the amount of interest payable for the same period. The same
observations apply mutatis mutandis to the case of a boom.
It follows that with the actual practices and institutions of
the contemporary world it is more expedient to aim at a rigid
money-wage policy than at a flexible policy responding by easy stages
to changes in the amount of unemployment; ― so far, that is to say, as
the marginal efficiency of capital is concerned. But is this conclusion
upset when we turn to the rate of interest?
It is, therefore, on the effect of a falling wage- and
price-level on the demand for money that those who believe in the
self-adjusting quality of the economic system must rest the weight of
their argument; though I am not aware that they have done so. If the
quantity of money is itself a function of the wage- and price-level,
there is indeed, nothing to hope in this direction. But if the quantity
of money is virtually fixed, it is evident that its quantity in terms
of wage-units can be indefinitely increased by a sufficient reduction
in money-wages; and that its quantity in proportion to incomes
generally can be largely increased, the limit to this increase
depending on the proportion of wage-cost to marginal prime-cost and on
the response of other elements of marginal prime-cost to the falling
wage-unit.
We can, therefore, theoretically at least, produce precisely the same
effects on the rate of interest by reducing wages, whilst leaving the
quantity of money unchanged, that we can produce by increasing the
quantity of money whilst leaving the level of wages unchanged. It
follows that wage reductions, as a method of securing full employment,
are also subject to the same limitations as the method of increasing
the quantity of money. The same reasons as those mentioned above, which
limit the efficacy of increases in the quantity of money as a means of
increasing investment to the optimum figure, apply mutatis mutandis to
wage reductions. Just as a moderate increase in the quantity of money
may exert an inadequate influence over the long-term rate of interest,
whilst an immoderate increase may offset its other advantages by its
disturbing effect on confidence; so a moderate reduction in money-wages
may prove inadequate, whilst an immoderate reduction might shatter
confidence even if it were practicable.
There is, therefore, no ground for the belief that a flexible wage
policy is capable of maintaining a state of continuous full employment;
― any more than for the belief than an open-market monetary policy is
capable, unaided, of achieving this result. The economic system cannot
be made self-adjusting along these lines.
If, indeed, labour were always in a position to take action (and
were to do so), whenever there was less than full employment, to reduce
its money demands by concerted action to whatever point was required to
make money so abundant relatively to the wage-unit that the rate of
interest would fall to a level compatible with full employment, we
should, in effect, have monetary management by the Trade Unions, aimed
at full employment, instead of by the banking system.
Nevertheless while a flexible wage policy and a flexible money policy
come, analytically, to the same thing, inasmuch as they are alternative
means of changing the quantity of money in terms of wage-units, in
other respects there is, of course, a world of difference between them.
Let me briefly recall to the reader's mind the three outstanding
considerations.
(i) Except in a socialised community where wage-policy is settled by
decree, there is no means of securing uniform wage reductions for every
class of labour. The result can only be brought about by a series of
gradual, irregular changes, justifiable on no criterion of social
justice or economic expediency, and probably completed only after
wasteful and disastrous struggles, where those in the weakest
bargaining position will suffer relatively to the rest. A change in the
quantity of money, on the other hand, is already within the power of
most governments by open-market policy or analogous measures. Having
regard to human nature and our institutions, it can only be a foolish
person who would prefer a flexible wage policy to a flexible money
policy, unless he can point to advantages from the former which are not
obtainable from the latter. Moreover, other things being equal, a
method which it is comparatively easy to apply should be deemed
preferable to a method which is probably so difficult as to be
impracticable.
(ii) If money-wages are inflexible, such changes in prices as occur
(i.e. apart from “administered “ or monopoly prices which are
determined by other considerations besides marginal cost) will mainly
correspond to the diminishing marginal productivity of the existing
equipment as the output from it is increased. Thus the greatest
practicable fairness will be maintained between labour and the factors
whose remuneration is contractually fixed in terms of money, in
particular the rentier class and persons with fixed salaries on the
permanent establishment of a firm, an institution or the State. If
important classes are to have their remuneration fixed in terms of
money in any case, social justice and social expediency are best served
if the remunerations of all factors are somewhat inflexible in terms of
money. Having regard to the large groups of incomes which are
comparatively inflexible in terms of money, it can only be an unjust
person who would prefer a flexible wage policy to a flexible money
policy, unless he can point to advantages from the former which are not
obtainable from the latter.
(iii) The method of increasing the quantity of money in terms of
wage-units by decreasing the wage-unit increases proportionately the
burden of debt; whereas the method of producing the same result by
increasing the quantity of money whilst leaving the wage-unit unchanged
has the opposite effect. Having regard to the excessive burden of many
types of debt, it can only be an inexperienced person who would prefer
the former.
(iv) If a sagging rate of interest has to be brought about by a sagging
wage-level, there is, for the reasons given above, a double drag on the
marginal efficiency of capital and a double reason for putting off
investment and thus postponing recovery.
III
It follows, therefore, that if labour were to respond to
conditions of gradually diminishing employment by offering its services
at a gradually diminishing money-wage, this would not, as a rule, have
the effect of reducing real wages and might even have the effect of
increasing them, through its adverse influence on the volume of output.
The chief result of this policy would be to cause a great instability
of prices, so violent perhaps as to make business calculations futile
in an economic society functioning after the manner of that in which we
live. To suppose that a flexible wage policy is a right and proper
adjunct of a system which on the whole is one of laissez-faire, is the
opposite of the truth. It is only in a highly authoritarian society,
where sudden, substantial, all-round changes could be decreed that a
flexible wage-policy could function with success. One can imagine it in
operation in Italy, Germany or Russia, but not in France, the United
States or Great Britain.
If, as in Australia, an attempt were made to fix real wages by
legislation., then there would be a certain level of employment
corresponding to that level of real wages; and the actual level of
employment would, in a closed system, oscillate violently between that
level and no employment at all, according as the rate of investment was
or was not below the rate compatible with that level; whilst prices
would be in unstable equilibrium when investment was at the critical
level, racing to zero whenever investment was below it, and to infinity
whenever it was above it. The element of stability would have to be
found, if at all, in the factors controlling the quantity of money
being so determined that there always existed some level of money-wages
at which the quantity of money would be such as to establish a relation
between the rate of interest and the marginal efficiency of capital
which would maintain investment at the critical level. In this event
employment would be constant (at the level appropriate to the legal
real wage) with money-wages and prices fluctuating rapidly in the
degree just necessary to maintain this rate of investment at the
appropriate figure. In the actual case of Australia, the escape was
found, partly of course in the inevitable inefficacy of the legislation
to achieve its object, and partly in Australia not being a closed
system, so that the level of money-wages was itself a determinant of
the level of foreign investment and hence of total investment, whilst
the terms of trade were an important influence on real wages.
In the light of these considerations I am now of the opinion
that the maintenance of a stable general level of money-wages is, on a
balance of considerations, the most advisable policy for a closed
system; whilst the same conclusion will hold good for an open system,
provided that equilibrium with the rest of the world can be secured by
means of fluctuating exchanges. There are advantages in some degree of
flexibility in the wages of particular industries so as to expedite
transfers from those which are relatively declining to those which are
relatively expanding. But the money-wage level as a whole should be
maintained as stable as possible, at any rate in the short period.
This policy will result in a fair degree of stability in the
price-level;-greater stability, at least, than with a flexible wage
policy. Apart from “administered” or monopoly prices, the price-level
will only change in the short period in response to the extent that
changes in the volume of employment affect marginal prime-costs; whilst
in the long period they will only change in response to changes in the
cost of production due to new technique and new or increased equipment.
It is true that, if there are, nevertheless, large fluctuations
in employment, substantial fluctuations in the price-level will
accompany them. But the fluctuations will be less, as I have said
above, than with a flexible wage policy.
Thus with a rigid wage policy the stability of prices will be bound up
in the short period with the avoidance of fluctuations in employment.
In the long period, on the other hand, we are still left with the
choice between a policy of allowing prices to fall slowly with the
progress of technique and equipment whilst keeping wages stable, or of
allowing wages to rise slowly whilst keeping prices stable. On the
whole my preference is for the latter alternative, on account of the
fact that it is easier with an expectation of higher wages in future to
keep the actual level of employment within a given range of full
employment than with an expectation of lower wages in future, and on
account also of the social advantages of gradually diminishing the
burden of debt, the greater ease of adjustment from decaying to growing
industries, and the psychological encouragement likely to be felt from
a moderate tendency for money-wages to increase. But no essential point
of principle is involved, an it would lead me beyond the scope of my
present purpose to develop in detail the arguments on either side.
Author's Footnotes
[1]. In an appendix to this chapter Professor Pigou's Theory of Unemployment is criticised in detail.
Appendix to Chapter 19. Professor Pigou's “Theory of Unemployment”
第１９章の付録、ピグー教授の『失業の理論』
PROFESSOR PIGOU in his Theory of Unemployment makes the volume of
employment to depend on two fundamental factors, namely (1) the real
rates of wages for which workpeople stipulate（要求する）, and (2) the shape
of the Real Demand Function for Labour（実質需要関数）. The central sections of
his book are concerned with determining the shape of the latter
function. The fact that workpeople in fact stipulate, not for a real
rate of wages, but for a money-rate, is not ignored; but, in effect, it
is assumed that the actual money-rate of wages divided by the price of
wage-goods can be taken to measure the real rate demanded.
ピグー教授は『失業理論』のなかで雇用量は二つの基本的な要因に左右されると言っている。その（１）は労働者たちが要求する実質賃金率であり、その（２）
が実質労働需要関数であると。彼の本の中心部分はこの関数の形を決めることに費やされている。労働者側が実際に要求するのは実質賃金率ではなく、名目賃金
率であることは無視されてはいない。しかし、要するに、実際の名目賃金を賃金財の価格で割った値をもって、要求されている実質賃金率と見なすことが出来る
としている。
The equations which, as he says, “form the starting point of the
enquiry” into the Real Demand Function for Labour are given in his
Theory of Unemployment, p. 90. Since the tacit assumptions, which
govern the application of his analysis, slip in near the outset（初め） of
his argument, I will summarise his treatment（議論） up to the crucial
point.
実質労働需要関数に対する彼の言う「研究の出発点」となる方程式は、彼の『失業理論』の９０頁に出ている。彼の分析を支配している暗黙の前提が彼の議論のごく最初のところに忍び込んでいるので、重要な点までの彼の議論を要約してみたい。
Professor Pigou divides industries into those “engaged in making
wage-goods at home and in making exports the sale of which creates
claims to wage-goods abroad（輸出品の販売によって海外の賃金財を購入する権利が生まれる）” and the
“other” industries: which it is convenient to call the wage-goods
industries and the non-wage-goods industries respectively.
ピグー教授は産業を「国内で賃金財を作る産業と輸出品を作る産業（その販売の御陰で海外の賃金剤を買う権利が生まれる）と他の産業」に分けている。これを便宜上、賃金財産業と非賃金財産業と呼ぶことにする。
He supposes x men to be employed in the former and y men in the latter.
The output in value of wage-goods of the x men he calls F(x); and the
general rate of wages F'(x).
彼は賃金財産業にｘ人が雇われ非賃金財産業にｙ人が雇われているとする。そしてｘ人の産出量を賃金財の価値で表したものを彼はＦ(ｘ)（＝主要費用）とし、全体的な賃金率をＦ'(ｘ)（＝限界賃金費用＝限界主要費用）としている。
This, though he does not stop to mention it, is tantamount to assuming
that marginal wage-cost is equal to marginal prime-cost.[1]
ピグー教授はわざわざ言及していないが、これは限界賃金費用が限界主要費用と一致すると想定しているに等しい。
Further, he assumes that x + y = φ(x), i.e. that the number of men
employed in the wage-goods industries is a function of total
employment.
さらに彼は ｘ＋ｙ = φ(ｘ)として、賃金財産業に雇用された人の数が総雇用関数であると考える。
He then shows that the elasticity of the real demand for labour in the
aggregate (which gives us the shape of our quaesitum, namely the Real
Demand Function for Labour) can be written
Er = (φ'(x)/φ(x)) . (F'(x)/F''(x))
それから彼は「総計としての労働の実質需要の弾力性」（これは我々が求める実質労働需要関数の形そのものである）は次の式で表わせるという。
Ｅｒ ＝ （φ'（ｘ）／φ（ｘ））×（Ｆ'（ｘ）／Ｆ''（ｘ））（＝雇用の変化率÷限界賃金の変化率）
So far as notation goes, there is no significant difference between
this and my own modes of expression. In so far as we can identify
Professor Pigou's wage-goods with my consumption-goods, and his “other
goods” with my investment-goods, it follows that his (F(x)/F'(x)),
being the value of the output of the wage-goods industries in terms of
the wage-unit, is the same as my Cw.
記号に関する限り、これは私の表記法と大きな違いはない。ピグー教授の賃金財と私の消費財を、彼の他の財を私の投資財に等しいとみなせるなら、単位賃金あたりの賃金財産業の産出物の価値である彼のＦ（ｘ）／Ｆ'（ｘ）は私のＣｗと等しい。
Furthermore, his function φ is (subject to the identification of
wage-goods with consumption-goods) a function of what I have called
above the employment multiplier k'. For
Δx = k'Δy ,
so that
φ'(x) = 1 + (1/k') .
さらに、彼の関数φは（賃金財を消費財と同じとすると）私が上記で雇用定数ｋ'と呼んだものの関数である。というのは、
Δｘ＝ｋ'Δｙ
なので、（φ（ｘ）＝ｘ＋ｙ、φ'（ｘ）＝１＋Δｙ／Δｘ、Δｙ／Δｘ＝１／ｋ'だから）
φ'（ｘ）＝１＋（１／ｋ'） となる。
Thus Professor Pigou's “elasticity of the real demand for labour in the
aggregate” is a concoction similar to some of my own, depending partly
on the physical and technical conditions in industry (as given by his
function F) and partly on the propensity to consume wage-goods (as
given by his function φ); provided always that we are limiting
ourselves to the special case where marginal labour-cost is equal to
marginal prime-cost.
このように、ピグー教授の「総計としての労働の実質需要の弾力性」は私のものに似た作りで、一部は産業の物理的かつ技術的条件（彼の関数Ｆによって与えら
れる）に依存し、一部は賃金財の消費性向（彼の関数φによって与えられる）に依存している。もちろん、これは限界労働コストが限界主要費用に等しいという
特別な場合に限定した場合のことである。
To determine the quantity of employment, Professor Pigou then combines
with his “real demand for labour”, a supply function for labour. He
assumes that this is a function of the real wage and of nothing else.
But, as he has also assumed that the real wage is a function of the
number of men x who are employed in the wage-goods industries, this
amounts to assuming that the total supply of labour at the existing
real wage is a function of x and of nothing else. That is to say, n =
χ(x), where n is the supply of labour available at a real wage F'(x).
次に、ピグー教授は雇用量を決定するために、彼の「労働の実質需要」と労働の供給関数を組み合わせている。この労働の供給関数を彼は実質賃金だけの関数で
あると想定している。しかし、彼はまた実質賃金は賃金財産業に雇われている人間の数ｘの関数であるとも想定している。ということは、現行実質賃金財におけ
る総労働供給はｘだけの関数であるということになる。つまり、ｎを実質賃金Ｆ'（ｘ）において利用可能な労働供給とすると、ｎ＝
χ（ｘ）であるということである。
Thus, cleared of all complication, Professor Pigou's analysis amounts
to an attempt to discover the volume of actual employment from the
equations
x + y = φ(x) and n = χ(x) .
こうして複雑な要素を取り除いていくと、ピグー教授の分析は次の２つの方程式
ｘ＋ｙ ＝ φ（ｘ） と ｎ＝χ（ｘ） から現実の雇用量を見つける試みだと言っていい。
But there are here three unknowns and only two equations. It seems
clear that he gets round this difficulty by taking n = x + y. This
amounts, of course, to assuming that there is no involuntary
unemployment in the strict sense, i.e. that all labour available at the
existing real wage is in fact employed. In this case x has the value
which satisfies the equation
φ(x) = χ(x) ;
and when we have thus found that the value of x is equal to (say) n1, y
must be equal to χ(n1) - n1, and total employment n is equal to χ(n1).
しかし、ここには三つの未知数があるのに二つの方程式しかない。この難問を回避するために彼がｎ＝ｘ＋ｙとしていることは明らかである。これは厳密な意味
での「非自発的失業」が存在せず、現行実質賃金によって利用出来る全ての労働力が実際に雇用されている、と想定することになる。この場合、ｘは次の方程式
を満たす値を持つ。
φ（ｘ）＝χ（ｘ）
そしてｘの値を仮にｎ１とすると、ｙはχ（ｎ１）ーｎ１と等しくなり、総雇用ｎはχ（ｎ１）と等しくなる。
It is worth pausing for a moment to consider what this involves.
It means that, if the supply function of labour changes, more labour
being available at a given real wage (so that n1+dn1 is now the value
of x which satisfies the equation φ(x) =χ(x)), the demand for the
output of the non-wage-goods industries is such that employment in
these industries is bound to increase by just the amount which will
preserve equality between φ(n1 + dn1) and χ(n1+dn1). The only other way
in which it is possible for aggregate employment to change is through a
modification of the propensity to purchase wage-goods and
non-wage-goods respectively such that there is an increase of y
accompanied by a greater decrease of x.
ここでしばらく立ち止まってこの事の意味を考えてみよう。
The assumption that n = x + y means, of course, that labour is always
in a position to determine its own real wage. Thus, the assumption that
labour is in a position to determine its own real wage, means that the
demand for the output of the non-wage-goods industries obeys the above
laws. In other words, it is assumed that the rate of interest always
adjusts itself to the schedule of the marginal efficiency of capital in
such a way as to preserve full employment. Without this assumption
Professor Pigou's analysis breaks down and provides no means of
determining what the volume of employment will be. It is, indeed,
strange that Professor Pigou should have supposed that he could furnish
a theory of unemployment which involves no reference at all to changes
in the rate of investment (i.e. to changes in employment in the
non-wage-goods industries) due, not to a change in the supply function
of labour, but to changes in (e.g.) either the rate of interest or the
state of confidence.
His title the “Theory of Unemployment” is, therefore, something of a
misnomer. His book is not really concerned with this subject. It is a
discussion of how much employment there will be, given the supply
function of labour, when the conditions for full employment are
satisfied. The purpose of the concept of the elasticity of the real
demand for labour in the aggregate is to show by how much full
employment will rise or fall corresponding to a given shift in the
supply function of labour. Or ― alternatively and perhaps better ― we
may regard his book as a non-causative investigation into the
functional relationship which determines what level of real wages will
correspond to any given level of employment. But it is not capable of
telling us what determines the actual level of employment; and on the
problem of involuntary unemployment it has no direct bearing.
If Professor Pigou were to deny the possibility of involuntary
unemployment in the sense in which I have defined it above, as,
perhaps, he would, it is still difficult to see how his analysis could
be applied. For his omission to discuss what determines the connection
between x and y, i.e. between employment in the wage-goods and
non-wage-goods industries respectively, still remains fatal.
Moreover, he agrees that within certain limits labour in fact often
stipulates, not for a given real wage, but for a given money-wage. But
in this case the supply function of labour is not a function of F'(x)
alone but also of the money-price of wage-goods; ― with the result that
the previous analysis breaks down and an additional factor has to be
introduced, without there being an additional equation to provide for
this additional unknown. The pitfalls of a pseudo-mathematical method,
which can make no progress except by making everything a function of a
single variable and assuming that all the partial differentials vanish,
could not be better illustrated. For it is no good to admit later on
that there are in fact other variables, and yet to proceed without
re-writing everything that has been written up to that point. Thus if
(within limits) it is a money-wage for which labour stipulates, we
still have insufficient data, even if we assume that n = x + y, unless
we know what determines the money-price of wage-goods. For, the
money-price of wage-goods depend on the aggregate amount of employment.
Therefore, we cannot say what aggregate employment will be, until we
know the money-price of wage-goods; and we cannot know the money-price
of wage-goods until we know the aggregate amount of employment. We are,
as I have said, one equation short. Yet it might be a provisional
assumption of a rigidity of money-wages, rather than of real wages,
which would bring our theory nearest to the facts. For example,
money-wages in Great Britain during the turmoil and uncertainty and
wide price fluctuations of the decade 1924-1934 were stable within a
range of 6 per cent., whereas real wages fluctuated by more than 20 per
cent. A theory cannot claim to be a general theory, unless it is
applicable to the case where (or the range within which) money-wages
are fixed, just as much as to any other case. Politicians are entitled
to complain that money-wages ought to be highly flexible; but a
theorist must be prepared to deal indifferently with either state of
affairs. A scientific theory cannot require the facts to conform to its
own assumptions.
When Professor Pigou comes to deal expressly with the effect of a
reduction of money-wages, he again, palpably (to my mind), introduces
too few data to permit of any definite answer being obtainable. He
begins by rejecting the argument (op. cit. p. 101) that, if marginal
prime-cost is equal to marginal wage-cost, non-wage-earners' incomes
will be altered, when money-wages are reduced, in the same proportion
as wage-earners', on the ground that this is only valid, if the
quantity of employment remains unaltered ― which is the very point
under discussion. But he proceeds on the next page (op. cit. p. 102) to
make the same mistake himself by taking as his assumption that “at the
outset nothing has happened to non-wage-earners' money-income”, which,
as he has just shown, is only valid if the quantity of employment does
not remain unaltered ― which is the very point under discussion. In
fact, no answer is possible, unless other factors are included in our
data.
The manner in which the admission, that labour in fact stipulates for a
given money-wage and not for a given real wage (provided that the real
wage does not fall below a certain minimum), affects the analysis, can
also be shown by pointing out that in this case the assumption that
more labour is not available except at a greater real wage, which is
fundamental to most of the argument, breaks down. For example,
Professor Pigou rejects (Op. cit. p. 75) the theory of the
multiplier（乗数理論） by assuming that the rate of real wages is given, i.e.
that, there being already full employment, no additional labour is
forthcoming at a lower real wage. Subject to this assumption, the
argument is, of course, correct. But in this passage Professor Pigou is
criticising a proposal relating to practical policy; and it is
fantastically far removed from the facts to assume, at a time when
statistical unemployment in Great Britain exceeded 2,000,000 (i.e. when
there were 2,000,000 men willing to work at the existing money-wage),
that any rise in the cost of living, however moderate, relatively to
the money-wage would cause the withdrawal from the labour market of
more than the equivalent of all these 2,000,000 men.
労働者側が契約で明記するのは所与の名目賃金であって所与の実質賃金ではないことを認めることは、分析にどのように影響を与えるかは、この場合には実質賃
金を上げない限り労働力の供給が増えることはないという議論の根底となる前提が崩壊することを指摘することでわかる。例えば、ピグー教授は、実質賃金率は
所与である、即ち、完全雇用なので、もう実質賃金を下げても労働需要が増えることはないと想定することによって、乗数理論を拒否する。
It is important to emphasise that the whole of Professor Pigou's
book is written on the assumption that any rise in the cost of living,
however moderate, relatively to the money-wage will cause the
withdrawal from the labour market of a number of workers greater than
that of all the existing unemployed.
Moreover, Professor Pigou does not notice in this passage (Op. cit. p.
75) that the argument, which he advances against “secondary” employment
as a result of public works, is, on the same assumptions, equally fatal
to increased “primary” employment from the same policy. For if the real
rate of wages ruling in the wage-goods industries is given, no
increased employment whatever is possible except, indeed, as a result
of non-wage-earners reducing their consumption of wage-goods. For those
newly engaged in the primary employment will presumably increase their
consumption of wage-goods which will reduce the real wage and hence (on
his assumptions) lead to a withdrawal of labour previously employed
elsewhere. Yet Professor Pigou accepts, apparently, the possibility of
increased primary employment. The line between primary and secondary
employment seems to be the critical psychological point at which his
good common sense ceases to overbear his bad theory.
The difference in the conclusions to which the above differences in
assumptions and in analysis lead can be shown by the following
important passage in which Professor Pigou sums up his point of view:
“With perfectly free competition among workpeople and labour perfectly
mobile, the nature of the relation (i.e. between the real wage-rates
for which people stipulate and the demand function for labour) will be
very simple. There will always be at work a strong tendency for
wage-rates to be so related to demand that everybody is employed.
Hence, in stable conditions everyone will actually be employed. The
implication is that such unemployment as exists at any time is due
wholly to the fact that changes in demand conditions are continually
taking place and that frictional resistances prevent the appropriate
wage adjustments from being made instantaneously.”[2]
He concludes (op. cit. p. 253) that unemployment is primarily due to a
wage policy which fails to adjust itself sufficiently to changes in the
real Jemand function for labour.
Thus Professor Pigou believes that in the long run unemployment can be
cured by wage adjustments;[3] whereas I maintain that the real wage
(subject only to a minimum set by the marginal disutility of
employment) is not primarily determined by “wage adjustments” (though
these may have repercussions) but by the other forces of the system,
some of which (in particular the relation between the schedule of the
marginal efficiency of capital and the rate of interest) Professor
Pigou has failed, if I am right, to include in his formal scheme.
Finally, when Professor Pigou comes to the “Causation of Unemployment”
he speaks, it is true, of fluctuations in the state of demand, much as
I do. But he identifies the state of demand with the Real Demand
Function for Labour, forgetful of how narrow a thing the latter is on
his definition. For the Real Demand Function for Labour depends by
definition (as we have seen above) on nothing but two factors, namely
(1) the relationship in any given environment between the total number
of men employed and the number who have to be employed in the
wage-goods industries to provide them with what they consume, and (2)
the state of marginal productivity in the wage-goods industries. Yet in
Part V. of his Theory of Unemployment fluctuations in the state of “the
real demand for labour” are given a position of importance. The “real
demand for labour” is regarded as a factor which is susceptible of wide
short-period fluctuations (op. cit. Part V. chaps. vi.-xii.), and the
suggestion seems to be that swings in “the real demand for labour” are,
in combination with the failure of wage policy to respond sensitively
to such changes, largely responsible for the trade cycle. To the reader
all this seems, at first, reasonable and familiar. For, unless he goes
back to the definition, “fluctuations in the real demand for labour”
will convey to his mind the same sort of suggestion as I mean to convey
by “fluctuations in the state of aggregate demand”. But if we go back
to the definition of the “real demand for labour”, all this loses its
plausibility. For we shall find that there is nothing in the world less
likely to be subject to sharp short-period swings than this factor.
Professor Pigou's “real demand for labour” depends by definition on
nothing but F(x), which represents the physical conditions of
production in the wage-goods industries, and φ(x), which represents the
functional relationship between employment in the wage-goods industries
and total employment corresponding to any given level of the latter. It
is difficult to see a reason why either of these functions should
change, except gradually over a long period. Certainly there seems no
reason to suppose that they are likely to fluctuate during a trade
cycle. For F(x) can only change slowly, and, in a technically
progressive community, only in the forward direction; whilst φ(x) will
remain stable, unless we suppose a sudden outbreak of thrift in the
working classes, or, more generally, a sudden shift in the propensity
to consume. I should expect, therefore, that the real demand for labour
would remain virtually constant throughout a trade cycle. I repeat that
Professor Pigou has altogether omitted from his analysis the unstable
factor, namely fluctuations in the scale of investment, which is most
often at the bottom of the phenomenon of fluctuations in employment.
I have criticised at length Professor Pigou's theory of
unemployment not because he seems to me to be more open to criticism
than other economists of the classical school; but because his is the
only attempt with which I am acquainted to write down the classical
theory of unemployment, precisely. Thus it has been incumbent on me to
raise my objections to this theory in the most formidable presentment
in which it has been advanced.
Author's Footnotes
[1]. The source of the fallacious practice of equating marginal
wage-cost（賃金コスト） to marginal prime-cost（主要費用） may, perhaps, be found in
an ambiguity in the meaning of marginal wage-cost. We might mean by it
the cost of an additional unit [of output,exclusive of any other
additonal cost] except additional wage-cost; or we might mean the
additional wage-cost involved in producing an additional unit of output
in the most economical way with the help of the existing equipment and
other unemployed factors.
限界賃金コストと限界主要費用を同一視する誤った習慣の原因は、限界賃金コストの意味の曖昧さにあると思われる。
我々は、この用語によって、追加の賃金コスト以外の[あらゆるコストを除外した]追加単位[を生産するため]のコストを意味したり、既存の設備と他の未使用要素を使って最も経済的に追加単位を産出するために必要な追加の賃金コストを意味したりするからである。
In the former case we are precluded from combining with the
additional labour any additional entrepreneurship or working capital or
anything else other than labour which would add to the cost; and we are
even precluded from allowing the additional labour to wear out the
equipment any faster than the smaller labour force would have done.
前者の場合、労働以外の何んであれ追加の企業家や追加の運転資本などコスト増につながるものを追加の労働に組み合わせてはてはならないし、追加の労働力によって以前より設備の摩耗が早まることもあってはならない。
Since in the former case we have forbidden any element of cost other
than labour cost to enter into marginal prime-cost, it does, of course,
follow that marginal wage-cost and marginal prime-cost are equal.
前者の場合、限界主要費用には労働コスト以外のどんなコストの要素も含めてはならないので、当然、限界労働コストと限界主要費用は同じことになってしまう。
But the results of an analysis conducted on this premiss have almost no
application, since the assumption on which it is based is very seldom
realised in practice. For we are not so foolish in practice as to
refuse to associate with additional labour appropriate additions of
other factors, in so far as they are available, and the assumption
will, therefore, only apply if we assume that all the factors, other
than labour, are already being employed to the utmost.
この前提で行われた分析の結果はほとんど妥当性を欠いている。この分析の基礎となる想定が実際に実行されることは殆どないからである。現実には我々は（＝
後者の場合のように）追加の労働に他の適当な追加の要素を可能な限り組み合わせる事を拒否するほど愚かではない。したがって、この想定は労働以外の他の要
素が全部すでに利用されてしまっていると考えない限りは、あり得ないのである。
[2]. Op. Cit. p. 252.
[3]. There is no hint or suggestion that this comes about through reactions on the rate of interest.
Chapter 20. The Employment Function[1]
I
IN Chapter 3 (p 25) we have defined the aggregate supply
function Z = φ(N), which relates the employment N with the aggregate
supply price of the corresponding output. The employment function only
differs from the aggregate supply function in that it is, in effect,
its inverse function and is defined in terms of the wage-unit; the
object of the employment function being to relate the amount of the
effective demand, measured in terms of the wage-unit, directed to a
given firm or industry or to industry as a whole with the amount of
employment, the supply price of the output of which will compare to
that amount of effective demand. Thus if an amount of effective demand
Dwr, measured in wage-units, directed to a firm or industry calls forth
an amount of employment Nr in that firm or industry, the employment
function is given by Nr = Fr(Dwr). Or, more Generally, if we are
entitled to assume that Dwr is a unique function of the total effective
demand Dw, the employment function is given by Nr = Fr(Dw). That is to
say, Nr men will be employed in industry r when effective demand is Dw.
We shall develop in this chapter certain properties of the employment
function. But apart from any interest which these may have, there are
two reasons why the substitution of the employment function for the
ordinary supply curve is consonant with the methods and objects of this
book. In the first place, it expresses the relevant facts in terms of
the units to which we have decided to restrict ourselves, without
introducing any of the units which have a dubious quantitative
character. In the second place, it lends itself to the problems of
industry and output as a whole, as distinct from the problems of a
single industry or firm in a given environment, more easily than does
the ordinary supply curve ― for the following reasons.
The ordinary demand curve for a particular commodity is drawn on some
assumption as to the incomes of members of the public, and has to be
re-drawn if the incomes change. In the same way the ordinary supply
curve for a particular commodity is drawn on some assumption as to the
output of industry as a whole and is liable to change if the aggregate
output of industry is changed. When, therefore, we are examining the
response of individual industries to changes in aggregate employment,
we are necessarily concerned, not with a single demand curve for each
industry, in conjunction with a single supply curve, but with two
families of such curves corresponding to different assumptions as to
the aggregate employment. In the case of the employment function,
however, the task of arriving at a function for industry as a whole
which will reflect changes in employment as a whole is more practicable.
For let us assume (to begin with) that the propensity to consume is
given as well as the other factors which we have taken as given in
Chapter 18 above, and that we are considering changes in employment in
response to changes in the rate of investment. Subject to this
assumption, for every level of effective demand in terms of wage-units
there will be a corresponding aggregate employment and this effective
demand will be divided in determinate proportions between consumption
and investment. Moreover, each level of effective demand will
correspond to a given distribution of income. It is reasonable,
therefore, further to assume that corresponding to a given level of
aggregate effective demand there is a unique distribution of it between
different industries.
This enables us to determine what amount of employment in each industry
will correspond to a given level of aggregate employment. That is to
say, it gives us the amount of employment in each particular industry
corresponding to each level of aggregate effective demand measured in
terms of wage-units, so that the conditions are satisfied for the
second form of the employment function for the industry, defined above,
namely Nr = Fr(Dw). Thus we have the advantage that, in these
conditions, the individual employment functions are additive in the
sense that the employment function for industry as a whole,
corresponding to a given level of effective demand, is equal to the sum
of the employment functions for each separate industry; i.e.
F(Dw) = N = ΣNr = ΣFr(Dw).
Next, let us define the elasticity of employment. The elasticity of employment for a given industry is
eer = dNr/dDwr . Dwr/Nr,
since it measures the response of the number of labour-units employed
in the industry to changes in the number of wage-units which are
expected to be spent on purchasing its output. The elasticity of
employment for industry as a whole we shall write
ee = (dN/dDw).(Dw/N) .
Provided that we can find some sufficiently satisfactory method of
measuring output, it is also useful to define what may be called the
elasticity of output or production, which measures the rate at which
output in any industry increases when more effective demand in terms of
wage-units is directed towards it, namely
eor = dOr/dDwr . Dwr/Or,
Provided we can assume that the price is equal to the marginal prime-cost, we then have
ΔDwr = 1/(1 - eor).ΔPr
where Pr is the expected profit.[2] It follows from this that if eor =
0, i.e. if the output of the industry is perfectly inelastic, the whole
of the increased effective demand (in terms of wage-units) is expected
to accrue to the entrepreneur as profit, i.e. ΔDwr = ΔPr; whilst if eor
= 1, i.e. if the elasticity of output is unity, no part of the
increased effective demand is expected to accrue as profit, the whole
of it being absorbed by the elements entering into marginal prime-cost.
Moreover, if the output of an industry is a function φ(Nr) of the labour employed in it, we have[3]
(1 - eor)/eer = - Nrφ''(Nr) / pwr{φ'(Nr)}2 ,
where pw is the expected price of a unit of output in terms of the
wage-unit. Thus the condition eor = 1 means that φ''(Nr) = 0, i.e. that
there are constant returns in response to increased employment.
Now, in so far as the classical theory assumes that real wages are
always equal to the marginal disutility of labour and that, the latter
increases when employment increases, so that the labour supply will
fall off, cet. par., if real wages are reduced, it is assuming that in
practice it is impossible to increase expenditure in terms of
wage-units. If this were true, the concept of elasticity of employment
would have no field of application. Moreover, it would, in this event,
be impossible to increase employment by increasing expenditure in terms
of money; for money-wages would rise proportionately to the increased
money expenditures so that there would be no increase of expenditure in
terms of wage-units and consequently no increase in employment. But if
the classical assumption does not hold good, it will be possible to
increase employment by increasing expenditure in terms of money until
real wages have fallen to equality with the marginal disutility of
labour, at which point there will, by definition, be full employment.
Ordinarily, of course, eor will have a value intermediate between zero
and unity. The extent to which prices (in terms of wage-units) will
rise, i.e. the extent to which real wages will fall, when money
expenditure is increased, depends, therefore, on the elasticity of
output in response to expenditure in terms of wage-units.
Let the elasticity of the expected price pwr in response to changes in
effective demand Dwr, namely (dpwr/dDwr).(Dwr/pwr), be written e'pr.
Since Or.pwr = Dwr, we have
dOr/dDwr . Dwr/Or + dpwr/dDwr . Dwr/pwr = 1
or
e'pr + eor = 1 .
That is to say, the sum of the elasticities of price and of output in
response to changes in effective demand (measured in terms of
wage-units) is equal to unity. Effective demand spends itself, partly
in affecting output and partly in affecting price, according to this
law.
If we are dealing with industry as a whole and are prepared to
assume that we have a unit in which output as a whole can be measured,
the same line of argument applies, so that e'p + eo = 1, where the
elasticities without a suffix r apply to industry as a whole.
Let us now measure values in money instead of wage-units and extend to
this case our conclusions in respect of industry as a whole.
If W stands for the money-wages of a unit of labour and p for
the expected price of a unit of output as a whole in terms of money, we
can write ep( = Ddp/pdD) for the elasticity of money-prices in response
to changes in effective demand measured in terms of money, and ew( =
DdW/WdD) for the elasticity of money-wages in response to changes in
effective demand in terms of money. It is then easily shown that
ep = 1 - eo(1 - ew). [4]
This equation is, as we shall see in the next chapter, a first step to a generalised Quantity Theory of Money.
If eo = 0 or if ew = 1, output will be unaltered and prices will
rise in the same proportion as effective demand in terms of money.
Otherwise they will rise in a smaller proportion.
II
Let us return to the employment function. We have assumed in the
foregoing that to every level of aggregate effective demand there
corresponds a unique distribution of effective demand between the
products of each individual industry. Now, as aggregate expenditure
changes, the corresponding expenditure on the products of an individual
industry will not, in general, change in the same proportion; ― partly
because individuals will not, as their incomes rise, increase the
amount of the products of each separate industry, which they purchase,
in the same proportion, and partly because the prices of different
commodities will respond in different degrees to increases in
expenditure upon them.
It follows from this that the assumption upon which we have
worked hitherto, that changes in employment depend solely on changes in
aggregate effective demand (in terms of wage-units), is no better than
a first approximation, if we admit that there is more than one way in
which an increase of income can be spent. For the way in which we
suppose the increase in aggregate demand to be distributed between
different commodities may considerably influence the volume of
employment. If, for example, the increased demand is largely directed
towards products which have a high elasticity of employment, the
aggregate increase in employment will be greater than if it is largely
directed towards products which have a low elasticity of employment.
In the same way employment may fall off without there having
been any change in aggregate demand, if the direction of demand is
change in favour of products having a relatively low elasticity of
employment.
These considerations are particularly important if we are concerned
with short-period phenomena in the sense of changes in the amount or
direction of demand which are not foreseen some time ahead. Some
products take time to produce, so that it is practically impossible to
increase the supply of them quickly. Thus, if additional demand is
directed to them without notice, they will show a low elasticity of
employment; although it may be that, given sufficient notice, their
elasticity of employment approaches unity.
It is in this connection that I find the principal significance
of the conception of a period of production. A product, I should prefer
to say[5] has a period of production n if n time-units of notice of
changes in the demand for it have to be given if it is to offer its
maximum elasticity of employment. Obviously consumption-goods, taken as
a whole, have in this sense the longest period of production, since of
every productive process they constitute the last stage. Thus if the
first impulse towards the increase in effective demand comes from an
increase in consumption, the initial elasticity of employment will be
further below its eventual equilibrium-level than if the impulse comes
from an increase in investment. Moreover, if the increased demand is
directed to products with a relatively low elasticity of employment, a
larger proportion of it will go to swell the incomes of entrepreneurs
and a smaller proportion to swell the incomes of wage-earners and other
prime-cost factors; with the possible result that the repercussions may
be somewhat less favourable to expenditure, owing to the likelihood of
entrepreneurs saving more of their increment of income than
wage-earners would. Nevertheless the distinction between the two cases
must not be over-stated, since a large part of the reactions will be
much the same in both.[6]
However long the notice given to entrepreneurs of a prospective change
in demand, it is not possible for the initial elasticity of employment,
in response to a given increase of investment, to be as great as its
eventual equilibrium value, unless there are surplus stocks and surplus
capacity at every stage of production. On the other hand, the depletion
of the surplus stocks will have an offsetting effect on the amount by
which investment increases. If we suppose that there are initially some
surpluses at every point, the initial elasticity of employment may
approximate to unity; then after the stocks have been absorbed, but
before an increased supply is coming forward at an adequate rate from
the earlier stages of production, the elasticity will fall away; rising
again towards unity as the new position of equilibrium is approached.
This is subject, however, to some qualification in so far as there are
rent factors which absorb more expenditure as employment increases, or
if the rate of interest increases. For these reasons perfect stability
of prices is impossible in an economy subject to change ― unless,
indeed, there is some peculiar mechanism which ensures temporary
fluctuations of just the right degree in the propensity to consume. But
price-instability arising in this way does not lead to the kind of
profit stimulus which is liable to bring into existence excess
capacity. For the windfall gain will wholly accrue to those
entrepreneurs who happen to possess products at a relatively advanced
stage of production, and there is nothing which the entrepreneur, who
does not possess specialised resources of the right kind, can do to
attract this gain to himself. Thus the inevitable price-instability due
to change cannot affect the actions of entrepreneurs, but merely
directs a defacto windfall of wealth into the laps of the lucky ones
(mutatis mutandis when the supposed change is in the other direction).
This fact has, I think, been overlooked in some contemporary
discussions of a practical policy aimed at stabilising prices. It is
true that in a society liable to change such a policy cannot be
perfectly successful. But it does not follow that every small temporary
departure from price stability necessarily sets up a cumulative
disequilibrium.
III
We have shown that when effective demand is deficient there is
under-employment of labour in the sense that there are men unemployed
who would be willing to work at less than the existing real wage.
Consequently, as effective demand increases, employment increases,
though at a real wage equal to or less than the existing one, until a
point comes at which there is no surplus of labour available at the
then existing real wage; i.e. no more men (or hours of labour)
available unless money-wages rise (from this point onwards) faster than
prices. The next problem is to consider what will happen if, when this
point has been reached, expenditure still continues to increase.
Up to this point the decreasing return from applying more labour to a
given capital equipment has been offset by the acquiescence of labour
in a diminishing real wage. But after this point a unit of labour would
require the inducement of the equivalent of an increased quantity of
product, whereas the yield from applying a further unit would be a
diminished quantity of product. The conditions of strict equilibrium
require, therefore, that wages and prices, and consequently profits
also, should all rise in the same proportion as expenditure, the “real”
position, including the volume of output and employment, being left
unchanged in all respects. We have reached, that is to say, a situation
in which the crude quantity theory of money (interpreting “velocity” to
mean “income-velocity”) is fully satisfied; for output does not alter
and prices rise in exact proportion to MV.
Nevertheless there are certain practical qualifications to this
conclusion which must be borne in mind in applying it to an actual case:
(1) For a time at least, rising prices may delude entrepreneurs into
increasing employment beyond the level which maximises their individual
profits measured in terms of the product. For they are so accustomed to
regard rising sale-proceeds in terms of money as a signal for expanding
production, that they may continue to do so when this policy has in
fact ceased to be to their best advantage; i.e. they may underestimate
their marginal user cost in the new price environment.
(2) Since that part of his profit which the entrepreneur has to hand on
to the rentier is fixed in terms of money, rising prices, even though
unaccompanied by any change in output, will re-distribute incomes to
the advantage of the entrepreneur and to the disadvantage of the
rentier, which may have a reaction on the propensity to consume. This,
however, is not a process which will have only begun when full
employment has been attained; ― it will have been making steady
progress all the time that the expenditure was increasing. If the
rentier is less prone to spend than the entrepreneur, the gradual
withdrawal of real income from the former will mean that full
employment will be reached with a smaller increase in the quantity of
money and a smaller reduction in the rate of interest than will be the
case if the opposite hypothesis holds. After full employment has been
reached, a further rise of prices will, if the first hypothesis
continues to hold, mean that the rate of interest will have to rise
somewhat !o prevent prices from rising indefinitely, and that the
increase in the quantity of money will be less than in proportion to
the increase in expenditure; whilst if the second hypothesis holds, the
opposite will be the case. It may be that, as the real income of the
rentier is diminished, a point will come when, as a result of his
growing relative impoverishment, there will be a changeover from the
first hypothesis to the second, which point may be reached either
before or after full employment has been attained.
IV
There is, perhaps, something a little perplexing in the apparent
asymmetry between Inflation and Deflation. For whilst a deflation of
effective demand below the level required for full employment will
diminish employment as well as prices, an inflation of it above this
level will merely affect prices. This asymmetry is, however, merely a
reflection of the fact that, whilst labour is always in a position to
refuse to work on a scale involving a real wage which is less than the
marginal disutility of that amount of employment, it is not in a
position to insist on being offered work on a scale involving a real
wage which is not greater than the marginal disutility of that amount
of employment.
Author's Footnotes
[1]. Those who (rightly) dislike algebra will lose little by omitting the first section of this chapter.
[2]. For, if pwr is the expected price of a unit of output in terms of the wage-unit,
ΔDwr = Δ (pwrOr) = pwrΔOr + OrΔpwr
= (Dwr/Or). ΔOr + OrΔpwr ,
so that
OrΔpwr = ΔDwr (1 - eor)
or
ΔDwr = OrΔpwr/(1 - eor) .
But
OrΔpwr = ΔDwr - pwrΔOr
= ΔDwr - (marginal prime-cost) ΔOr
= ΔP.
Hence
ΔDwr = 1/(1 - eor). ΔPr .
[3]. For, since Dwr = pwrOr, we have
1 = pwr. dOr/dDwr + Or.dpwr/dDwr
= eor - (Nrφ''(Nr)/{φ'(Nr)}2).eor/pwr .
[4]. For, since p = pw.W and D = Dw.W, we have
Δp = WΔpw + (p/W) . ΔW
= W. e'p.(pw/Dw).ΔDw + (p/W).ΔW
= e'p(p/D)(ΔD - (D/W)ΔW) + (p/W)ΔW
= e'p(p/D).ΔD + ΔW(p/W)(1 - e'p) ,
so that
ep = DΔp/pΔD) = e'p +(D/pΔD).ΔW.p/W).(1 - e'p)
= e'p + ew(1 - e'p)
= 1 - eo(1 - ew) .
[5]. This is not identical with the usual definition, but it seems to me to embody what is significant in the idea.
[6]. Some further discussion of the above topic is to be found in my Treatise on Money, Book IV.
Chapter 21. The Theory of Prices
I
SO long as economists are concerned with what is called the Theory of
Value, they have been accustomed to teach that prices are governed by
the conditions of supply and demand; and, in particular, changes in
marginal cost and the elasticity of short-period supply have played a
prominent part. But when they pass in volume II, or more often in a
separate treatise, to the Theory of Money and Prices, we hear no more
of these homely but intelligible concepts and move into a world where
prices are governed by the quantity of money, by its income-velocity,
by the velocity of circulation relatively to the volume of
transactions, by hoarding, by forced saving, by inflation and deflation
et hoc genus omne; and little or no attempt is made to relate these
vaguer phrases to our former notions of the elasticities of supply and
demand. If we reflect on what we are being taught and try to
rationalize it, in the simpler discussions it seems that the elasticity
of supply must have become zero and demand proportional to the quantity
of money; whilst in the more sophisticated we are lost in a haze where
nothing is clear and everything is possible. We have all of us become
used to finding ourselves sometimes on the one side of the moon and
sometimes on the other, without knowing what route or journey connects
them, related, apparently, after the fashion of our waking and our
dreaming lives.
One of the objects of the foregoing chapters has been to escape from
this double life and to bring the theory of prices as a whole back to
close contact with the theory of value. The division of Economics
between the Theory of Value and Distribution on the one hand and the
Theory of Money on the other hand is, I think, a false division. The
right dichotomy is, I suggest, between the Theory of the Individual
Industry or Firm and of the rewards and the distribution between
different uses of a given quantity of resources on the one hand, and
the Theory of Output and Employment as a whole on the other hand. So
long as we limit ourselves to the study of the individual industry or
firm on the assumption that the aggregate quantity of employed
resources is constant, and, provisionally, that the conditions of other
industries or firms are unchanged, it is true that we are not concerned
with the significant characteristics of money. But as soon as we pass
to the problem of what determines output and employment as a whole, we
require the complete theory of a Monetary Economy.
Or, perhaps, we might make our line of division between the theory of
stationary equilibrium and the theory of shifting equilibrium-meaning
by the latter the theory of a system in which changing views about the
future are capable of influencing the present situation. For the
importance of money essentially flows from its being a link between the
present and the future. We can consider what distribution of resources
between different uses will be consistent with equilibrium under the
influence of normal economic motives in a world in which our views
concerning the future are fixed and reliable in all respects; ― with a
further division, perhaps, between an economy which is unchanging and
one subject to change, but where all things are foreseen from the
beginning. Or we can pass from this simplified propaedeutic to the
problems of the real world in which our previous expectations are
liable to disappointment and expectations concerning the future affect
what we do to-day. It is when we have made this transition that the
peculiar properties of money as a link between the present and the
future must enter into our calculations. But, although the theory of
shifting equilibrium must necessarily be pursued in terms of a monetary
economy, it remains a theory of value and distribution and not a
separate “theory of money”. Money in its significant attributes is,
above all, a subtle device for linking the present to the future; and
we cannot even begin to discuss the effect of changing expectations on
current activities except in monetary terms. We cannot get rid of money
even by abolishing gold and silver and legal tender instruments. So
long as there exists any durable asset, it is capable of possessing
monetary attributes[1] and, therefore, of giving rise to the
characteristic problems of a monetary economy.
II
In a single industry its particular price-level depends partly
on the rate of remuneration of the factors of production which enter
into its marginal cost, and partly on the scale of output. There is no
reason to modify this conclusion when we pass to industry as a whole.
The general price-level depends partly on the rate of remuneration of
the factors of production which enter into marginal cost and partly on
the scale of output as a whole, i.e. (taking equipment and technique as
given) on the volume of employment. It is true that, when we pass to
output as a whole, the costs of production in any industry partly
depend on the output of other industries. But the more significant
change, of which we have to take account, is the effect of changes in
demand both on costs and on volume. It is on the side of demand that we
have to introduce quite new ideas when we are dealing with demand as a
whole and no longer with the demand for a single product taken in
isolation, with demand as a whole assumed to be unchanged.
III
If we allow ourselves the simplification of assuming that the
rates of remuneration of the different factors of production which
enter into marginal cost all change in the same proportion, i.e. in the
same proportion as the wage-unit, it follows that the general
price-level (taking equipment and technique as given) depends partly on
the wage-unit and partly on the volume of employment. Hence the effect
of changes in the quantity of money on the price-level can be
considered as being compounded of the effect on the wage-unit and the
effect on employment.
To elucidate the ideas involved, let us simplify our assumptions still
further, and assume (1) that all unemployed resources are homogeneous
and interchangeable in their efficiency to produce what is wanted, and
(2) that the factors of production entering into marginal cost are
content with the same money-wage so long as there is a surplus of them
unemployed. In this case we have constant returns and a rigid
wage-unit, so long as there is any unemployment. It follows that an
increase in the quantity of money will have no effect whatever on
prices, so long as there is any unemployment, and that employment will
increase in exact proportion to any increase in effective demand
brought about by the increase in the quantity of money; whilst as soon
as full employment is reached, it will thenceforward be the wage-unit
and prices which will increase in exact proportion to the increase in
effective demand. Thus if there is perfectly elastic supply so long as
there is unemployment, and perfectly inelastic supply so soon as full
employment is reached, and if effective demand changes in the same
proportion as the quantity of money, the Quantity Theory of Money can
be enunciated as follows: “So long as there is unemployment, employment
will change in the same proportion as the quantity of money; and when
there is full employment, prices will change in the same proportion as
the quantity of money”.
Having, however, satisfied tradition by introducing a sufficient number
of simplifying assumptions to enable us to enunciate a Quantity Theory
of Money, let us now consider the possible complications which will in
fact influence events:
(1) Effective demand will not change in exact proportion to the quantity of money.
(2) Since resources are not homogeneous, there will be diminishing, and not constant, returns as employment gradually increases.
(3) Since resources are not interchangeable, some commodities will
reach a condition of inelastic supply whilst there are still unemployed
resources available for the production of other commodities.
(4) The wage-unit will tend to rise, before full employment has been reached.
(5) The remunerations of the factors entering into marginal cost will not all change in the same proportion.
Thus we must first consider the effect of changes in the quantity of
money on the quantity of effective demand; and the increase in
effective demand will, generally speaking, spend itself partly in
increasing the quantity of employment and partly in raising the level
of prices. Thus instead of constant prices in conditions of
unemployment, and of prices rising in proportion to the quantity of
money in conditions of full employment, we have in fact a condition of
prices rising gradually as employment increases. The Theory of Prices,
that is to say, the analysis of the relation between changes in the
quantity of money and changes in the price-level with a view to
determining the elasticity of prices in response to changes in the
quantity of money, must, therefore, direct itself to the five
complicating factors set forth above.
We will consider each of them in turn. But this procedure must not be
allowed to lead us into supposing that they are, strictly speaking,
independent. For example, the proportion, in which an increase in
effective demand is divided in its effect between increasing output and
raising prices, may affect the way in which the quantity of money is
related to the quantity of effective demand. Or, again, the differences
in the proportions, in which the remunerations of different factors
change, may influence the relation between the quantity of money and
the quantity of effective demand. The object of our analysis is, not to
provide a machine, or method of blind manipulation, which will furnish
an infallible answer, but to provide ourselves with an organised and
orderly method of thinking out particular problems; and, after we have
reached a provisional conclusion by isolating the complicating factors
one by one, we then have to go back on ourselves and allow, as well as
we can, for the probable interactions of the factors amongst
themselves. This is the nature of economic thinking. Any other way of
applying our formal principles of thought (without which, however, we
shall be lost in the wood) will lead us into error. It is a great fault
of symbolic pseudo-mathematical methods of formalising a system of
economic analysis, such as we shall set down in section vi of this
chapter, that they expressly assume strict independence between the
factors involved and lose all their cogency and authority if this
hypothesis is disallowed; whereas, in ordinary discourse, where we are
not blindly manipulating but know all the time what we are doing and
what the words mean, we can keep “at the back of our heads” the
necessary reserves and qualifications and the adjustments which we
shall have to make later on, in a way in which we cannot keep
complicated partial differentials “at the back” of several pages of
algebra which assume that they all vanish. Too large a proportion of
recent “mathematical” economics are mere concoctions, as imprecise as
the initial assumptions they rest on, which allow the author to lose
sight of the complexities and interdependencies of the real world in a
maze of pretentious and unhelpful symbols.
IV
(i) The primary effect of a change in the quantity of money on the
quantity of effective demand is through its influence on the rate of
interest. If this were the only reaction, the quantitative effect could
be derived from the three elements ― (a) the schedule of
liquidity-preference which tells us by how much the rate of interest
will have to fall in order that the new money may be absorbed by
willing holders, (b) the schedule of marginal efficiencies which tells
us by how much a given fall in the rate of interest will increase
investment, and (c) the investment multiplier which tells us by how
much a given increase in investment will increase effective demand as a
whole.
But this analysis, though it is valuable in introducing order and
method into our enquiry, presents a deceptive simplicity, if we forget
that the three elements (a), (b) and (c) are themselves partly
dependent on the complicating factors (2), (3), (4) and (5) which we
have not yet considered. For the schedule of liquidity-preference
itself depends on how much of the new money is absorbed into the income
and industrial circulations, which depends in turn on how much
effective demand increases and how the increase is divided between the
rise of prices, the rise of wages, and the volume of output and
employment. Furthermore, the schedule of marginal efficiencies will
partly depend on the effect which the circumstances attendant on the
increase in the quantity of money have on expectations of the future
monetary prospects. And finally the multiplier will be influenced by
the way in which the new income resulting from the increased effective
demand is distributed between different classes of consumers. Nor, of
course, is this list of possible interactions complete. Nevertheless,
if we have all the facts before us, we shall have enough simultaneous
equations to give us a determinate result. There will be a determinate
amount of increase in the quantity of effective demand which, after
taking everything into account, will correspond to, and be in
equilibrium with, the increase in the quantity of money. Moreover, it
is only in highly exceptional circumstances that an increase in the
quantity of money will be associated with a decrease in the quantity of
effective demand.
The ratio between the quantity of effective demand and the quantity of
money closely corresponds to what is often called the “income-velocity
of money”; ― except that effective demand corresponds to the income the
expectation of which has set production moving, not to the actually
realised income, and to gross, not net, income. But the
“income-velocity of money” is, in itself, merely a name which explains
nothing. There is no reason to expect that it will be constant. For it
depends, as the foregoing discussion has shown, on many complex and
variable factors. The use of this term obscures, I think, the real
character of the causation, and has led to nothing but confusion.
(2) As we have shown above (Chapter 4. s. III), the distinction between
diminishing and constant returns partly depends on whether workers are
remunerated in strict proportion to their efficiency. If so, we shall
have constant labour-costs (in terms of the wage-unit) when employment
increases. But if the wage of a given grade of labourers is uniform
irrespective of the efficiency of the individuals, we shall have rising
labour-costs, irrespective of the efficiency of the equipment.
Moreover, if equipment is non-homogeneous and some part of it involves
a greater prime-cost per unit of output, we shall have increasing
marginal prime-costs over and above any increase due to increasing
labour-costs.
Hence, in general, supply price will increase as output. from a given
equipment is increased. Thus increasing output will be associated with
rising prices, apart from any change in the wage-unit.
(3) Under (2) we have been contemplating the possibility of supply
being imperfectly elastic. If there is a perfect balance in the
respective quantities of specialised unemployed resources, the point of
full employment will be reached for all of them simultaneously. But, in
general, the demand for some services and commodities will reach a
level beyond which their supply is, for the time being, perfectly
inelastic, whilst in other directions there is still a substantial
surplus of resources without employment. Thus as output increases, a
series of “bottlenecks” will be successively reached, where the supply
of particular commodities ceases to be elastic and their prices have to
rise to whatever level is necessary to divert demand into other
directions.
It is probable that the general level of prices will not rise
very much as output increases, so long as there are available efficient
unemployed resources of every type. But as soon as output has increased
sufficiently to begin to reach the “bottlenecks”, there is likely to be
a sharp rise in the prices of certain commodities.
Under this heading, however, as also under heading (2), the elasticity
of supply partly depends on the elapse of time. If we assume a
sufficient interval for the quantity of equipment itself to change, the
elasticities of supply will be decidedly greater eventually. Thus a
moderate change in effective demand, coming on a situation where there
is widespread unemployment, may spend itself very little in raising
prices and mainly in increasing employment; whilst a larger change,
which, being unforeseen, causes some temporary “bottle-necks” to be
reached, will spend itself in raising prices, as distinct from
employment, to a greater extent at first than subsequently.
(4) That the wage-unit may tend to rise before full employment has been
reached, requires little comment or explanation. Since each group of
workers will gain, cet. par., by a rise in its own wages, there is
naturally for all groups a pressure in this direction, which
entrepreneurs will be more ready to meet when they are doing better
business. For this reason a proportion of any increase in effective
demand is likely to be absorbed in satisfying the upward tendency of
the wage-unit.
Thus, in addition to the final critical point of full employment at
which money-wages have to rise, in response to an increasing effective
demand in terms of money, fully in proportion to the rise in the prices
of wage-goods, we have a succession of earlier semi-critical points at
which an increasing effective demand tends to raise money-wages though
not fully in proportion to the rise in the price of wage-goods; and
similarly in the case of a decreasing effective demand. In actual
experience the wage-unit does not change continuously in terms of money
in response to every small change in effective demand; but
discontinuously. These points of discontinuity are determined by the
psychology of the workers and by the policies of employers and trade
unions. In an open system, where they mean a change relatively to
wage-costs elsewhere, and in a trade cycle, where even in a closed
system they may mean a change relatively to expected wage-costs in the
future, they can be of considerable practical significance. These
points, where a further increase in effective demand in terms of money
is liable to cause a discontinuous rise in the wage-unit, might be
deemed, from a certain point of view, to be positions of
semi-inflation, having some analogy (though a very imperfect one) to
the absolute inflation (cf. Section V below) which ensues on an
increase in effective demand in circumstances of full employment. They
have, moreover, a good deal of historical importance. But they do not
readily lend themselves to theoretical generalisations.
(5) Our first simplification consisted in assuming that the
remunerations of the various factors entering into marginal cost all
change in the same proportion. But in fact the rates of remuneration of
different factors in terms of money will show varying degrees of
rigidity and they may also have different elasticities of supply in
response to changes in the money-rewards offered. If it were not for
this, we could say that the price-level is compounded of two factors,
the wage-unit and the quantity of employment.
Perhaps the most important element in marginal cost which is likely to
change in a different proportion from the wage-unit, and also to
fluctuate within much wider limits, is marginal user cost. For marginal
user cost may increase sharply when employment begins to improve, if
(as will probably be the case) the increasing effective demand brings a
rapid change in the prevailing expectation as to the date when the
replacement of equipment will be necessary.
Whilst it is for many purposes a very useful first approximation to
assume that the rewards of all the factors entering into marginal
prime-cost change in the same proportion as the wage-unit, it might be
better, perhaps, to take a weighted average of the rewards of the
factors entering into marginal prime-cost, and call this the cost-unit.
The cost-unit, or, subject to the above approximation, the wage-unit,
can thus be regarded as the essential standard of value; and the
price-level, given the state of technique and equipment, will depend
partly on the cost-unit and partly on the scale of output, increasing,
where output increases, more than in proportion to any increase in the
cost-unit, in accordance with the principle of diminishing returns in
the short period. We have full employment when output has risen to a
level at which the marginal return from a representative unit of the
factors of production has fallen to the minimum figure at which a
quantity of the factors sufficient to produce this output is available.
V
When a further increase in the quantity of effective demand produces no
further increase in output and entirely spends itself on an increase in
the cost-unit fully proportionate to the increase in effective demand,
we have reached a condition which might be appropriately designated as
one of true inflation. Up to this point the effect of monetary
expansion is entirely a question of degree, and there is no previous
point at which we can draw a definite line and declare that conditions
of inflation have set in. Every previous increase in the quantity of
money is likely, in so far as it increases effective demand, to spend
itself partly in increasing the cost-unit and partly in increasing
output.
It appears, therefore, that we have a sort of asymmetry on the
two sides of the critical level above which true inflation sets in. For
a contraction of effective demand below the critical level will reduce
its amount measured in cost-units; whereas an expansion of effective
demand beyond this level will not, in general, have the effect of
increasing its amount in terms of cost-units. This result follows from
the assumption that the factors of production, and in particular the
workers, are disposed to resist a reduction in their money-rewards, and
that there is no corresponding motive to resist an increase. This
assumption is, however, obviously well founded in the facts, due to the
circumstance that a change, which is not an all-round change, is
beneficial to the special factors affected when it is upward and
harmful when it is downward.
If, on the contrary, money-wages were to fall without limit
whenever there was a tendency for less than full employment, the
asymmetry would, indeed, disappear. But in that case there would be no
resting-place below full employment until either the rate of interest
was incapable of falling further or wages were zero. In fact we must
have some factor, the value of which in terms of money is, if not
fixed, at least sticky, to give us any stability of values in a
monetary system.
The view that any increase in the quantity of money is inflationary
(unless we mean by inflationary merely that prices are rising) is bound
up with the underlying assumption of the classical theory that we are
always in a condition where a reduction in the real rewards of the
factors of production will lead to a curtailment in their supply.
VI
With the aid of the notation introduced in Chapter 20 we can, if we wish, express the substance of the above in symbolic form.
Let us write MV = D where M is the quantity of money, V its
income-velocity (this definition differing in the minor respects
indicated above from the usual definition) and D the effective demand.
If, then, V is constant, prices will change in the same proportion as
the quantity of money provided that ep ( = Ddp/pdD), is unity. This
condition is satisfied (see Chapter 20 §I above) if eo = 0 or if ew =
1. The condition ew = 1 means that the wage-unit in terms of money
rises in the same proportion as the effective demand, since ew =
DdW/WdD ; and the condition eo = 0 means that output no longer shows
any response to a further increase in effective demand, since eo =
DdO/OdD. Output in either case will be unaltered.
Next, we can deal with the case where income-velocity is not constant,
by introducing yet a further elasticity, namely the elasticity, of
effective demand in response to changes in the quantity of money,
ed = MdD/DdM .
This gives us
Mdp/pdM = ep.ed where ep = 1 - ee.eo (1 - ew) ;
so that
e = ed - (1 - ew)ed . ee.eo
= ed (1 - ee. eo + ee.eo.ew)
where e without suffix ( = Mdp/pdM) stands for the apex of this pyramid
and measures the response of money-prices to changes in the quantity of
money.
Since this last expression gives us the proportionate change in prices
in response to a change in the quantity of money, it can be regarded as
a generalised statement of the Quantity Theory of Money. I do not
myself attach much value to manipulations of this kind; and I would
repeat the warning, which I have given above, that they involve just as
much tacit assumption as to what variables are taken as independent
(partial differentials being ignored throughout) as does ordinary
discourse, whilst I doubt if they carry us any further than ordinary
discourse can. Perhaps the best purpose served by writing them down is
to exhibit the extreme complexity of the relationship between prices
and the quantity of money, when we attempt to express it in a formal
manner. It is, however, worth pointing out that, of the four terms ed,
ew, ee and eo upon which the effect on prices of changes in the
quantity of money depends, ed stands for the liquidity factors which
determine the demand for money in each situation, ew for the labour
factors (or, more strictly, the factors entering into prime-cost) which
determine the extent to which money-wages are raised as employment
increases, and ee and eo for the physical factors which determine the
rate of decreasing returns as more employment is applied to the
existing equipment.
If the public hold a constant proportion of their income in
money, ed = 1; if money-wages are fixed, ew = 0; if there are constant
returns throughout so that marginal return equals average return, eeeo
= 1; and if there is full employment either of labour or of equipment,
eeeo = 0.
Now e = 1, if ed = 1 and ew = 1; or if ed = 1, ew = 0 and ee.eo = 1; or
if ed = 1 and eo = 0. And obviously there is a variety of other special
cases in which e = 1. But in general e is not unity; and it is,
perhaps, safe to make the generalisation that on plausible assumptions
relating to the real world, and excluding the case of a “flight from
the currency” in which ed and ew become large, e is, as a rule, less
than unity.
VII
So far, we have been primarily concerned with the way in which changes
in the quantity of money affect prices in the short period. But in the
long run is there not some simpler relationship?
これまで我々は主に貨幣の流通量の変化がどのようにして短期においては物価に影響を与えるかについて考えてきた。それに対して、長期においては、もっと単純な関係があるのではないだろうか。
This is a question for historical generalisation rather than for pure
theory. If there is some tendency to a measure of long-run uniformity
in the state of liquidity-preference, there may well be some sort of
rough relationship between the national income and the quantity of
money required to satisfy liquidity-preference, taken as a mean over
periods of pessimism and optimism together. There may be, for example,
some fairly stable proportion of the national income more than which
people will not readily keep in the shape of idle balances or long
periods together, provided the rate of interest exceeds a certain
psychological minimum; so that if the quantity of money beyond what is
required in the active circulation is in excess of this proportion of
the national income, there will be a tendency sooner or later for the
rate of interest to fall to the neighbourhood of this minimum. The
falling rate of interest will then, cet. par., increase effective
demand, and the increasing effective demand will reach one or more of
the semi-critical points at which the wage-unit will tend to show a
discontinuous rise, with a corresponding effect on prices.
この問題は純粋な理論ではなく歴史的な一般化の問題である。流動性選好にはある程度長期間にわたって一定である傾向があるとするならば、流動性選好を満た
すために必要な貨幣量と国民所得との間には何か大雑把な関係があって、それを楽観主義と悲観主義の間の均衡状態として受け取ってよいはずである。例えば、
仮に利子率が心理的に最低水準を超えていれば人々はもはや遊休資金として長期間手元に多くの金を持とうとしなくなるので、国民が手元に置こうとする貨幣量
が国民所得に占める割合はかなり安定しているかもしれない。だから、もし貨幣の循環に必要な以上の貨幣量が流通していて、それが国民所得とのこの割合を超
えている場合には、利子率は早晩この最低レベルの近くまで低がろうとするだろう（＝お金が増えると利子率が下がる。１３章）。利子率が下がれば、他の事情
が同じなら、有効需要を増やす。増えた有効需要が危険な点に到達すると、単位賃金の上昇は不連続になるとともに、物価に影響を及ぼす。
The opposite tendencies will set in if the quantity of surplus money is
an abnormally low proportion of the national income. Thus the net
effect of fluctuations over a period of time will be to establish a
mean figure in conformity with the stable proportion between the
national income and the quantity of money to which the psychology of
the public tends sooner or later to revert.
余剰貨幣の量が国民所得の異常に小さな割合を占めるようになると、逆の傾向が発生する。つまり、変動がもたらす一定の期間の後における最終的効果は、社会の心理的な傾向が早晩戻っていく国民所得と貨幣量の安定した割合とよく調和した均衡値を確立することである。
These tendencies will probably work with less friction in the upward
than in the downward direction. But if the quantity of money remains
very deficient for a long time, the escape will be normally found in
changing the monetary standard or the monetary system so as to raise
the quantity of money, rather than in forcing down the wage-unit and
thereby increasing the burden of debt. Thus the very long-run course of
prices has almost always been upward. For when money is relatively
abundant, the wage-unit rises; and when money is relatively scarce,
some means is found to increase the effective quantity of money.
このような傾向は上向きの時のほうが下向きの時よりよりスムーズに働くと思われる。しかし、もし帰り料が長期にわたって不足状態になると、その解決策は、
単位賃金を下げさせて借金の重荷を増やすのではなくて、普通は貨幣量を増やすために通貨制度や通貨基準を変更しようとすることに見出されるだろう。つま
り、非常に長期の物価の動きは常にこれまでほぼ上向きなのである。というのは、通貨が供給過剰であるときに、単位賃金は上昇するからである。そして、通貨
が供給不足の時には、有効に通貨量を増やす何らかの方策が取られるのである。
During the nineteenth century, the growth of population and of
invention, the opening-up of new lands, the state of confidence and the
frequency of war over the average of (say) each decade seem to have
been sufficient, taken in conjunction with the propensity to consume,
to establish a schedule of the marginal efficiency of capital which
allowed a reasonably satisfactory average level of employment to be
compatible with a rate of interest high enough to be psychologically
acceptable to wealth-owners. There is evidence that for a period of
almost one hundred and fifty years the long-run typical rate of
interest in the leading financial centres was about 5 pet cent., and
the gilt-edged rate between 3 and 3 1/2 per cent.; and that these rates
of interest were modest enough to encourage a rate of investment
consistent with an average of employment which was not intolerably low.
Sometimes the wage-unit, but more often the monetary standard or the
monetary system (in particular through the development of bank-money),
would be adjusted so as to ensure that the quantity of money in terms
of wage-units was sufficient to satisfy normal liquidity-preference at
rates of interest which were seldom much below the standard rates
indicated above. The tendency of the wage-unit was, as usual, steadily
upwards on the whole, but the efficiency of labour was also increasing.
Thus the balance of forces was such as to allow a fair measure of
stability of prices; ― the highest quinquennial average for Sauerbeck's
index number between 1820 and 1914 was only 50 per cent. above the
lowest. This was not accidental. It is rightly described as due to a
balance of forces in an age when individual groups of employers were
strong enough to prevent the wage-unit from rising much faster than the
efficiency of production, and when monetary systems were at the same
time sufficiently fluid and sufficiently conservative to provide an
average supply of money in terms of wage-units which allowed to prevail
the lowest average rate of interest readily acceptable by wealth-owners
under the influence of their liquidity-preferences. The average level
of employment was, of course, substantially below full employment, but
not so intolerably below it as to provoke revolutionary changes.
To-day and presumably for the future the schedule of the marginal
efficiency of capital is, for a variety of reasons, much lower than it
was in the nineteenth century. The acuteness and the peculiarity of our
contemporary problem arises, therefore, out of the possibility that the
average rate of interest which will allow a reasonable average level of
employment is one so unacceptable to wealth-owners that it cannot be
readily established merely by manipulating the quantity of money. So
long as a tolerable level of employment could be attained on the
average of one or two or three decades merely by assuring an adequate
supply of money in terms of wage-units, even the nineteenth century
could find a way. If this was our only problem now ― if a sufficient
degree of devaluation is all we need ― we, to-day, would certainly find
a way.
But the most stable, and the least easily shifted, element in our
contemporary economy has been hitherto, and may prove to be in future,
the minimum rate of interest acceptable to the generality of
wealth-owners.[2] If a tolerable level of employment requires a rate of
interest much below the average rates which ruled in the nineteenth
century, it is most doubtful whether it can be achieved merely by
manipulating the quantity of money. From the percentage gain, which the
schedule of marginal efficiency of capital allows the borrower to
expect to earn, there has to be deducted (1) the cost of bringing
borrowers and lenders together, (2) income and surtaxes and (3) the
allowance which the lender requires to cover his risk and uncertainty,
before we arrive at the net yield available to tempt the wealth-owner
to sacrifice his liquidity. If, in conditions of tolerable average
employment, this net yield turns out to be infinitesimal, time-honoured
methods may prove unavailing.
To return to our immediate subject, the long-run relationship between
the national income and the quantity of money will depend on
liquidity-preferences. And the long-run stability or instability of
prices will depend on the strength of the upward trend or the wage-unit
(or, more precisely, of the cost-unit) compared with the rate of
increase in the efficiency of the productive system.
Author's Footnotes
[1]. Cf. Chapter 17 above.
[2]. Cf. the nineteenth-century saying, quoted by Bagehot, that “John
Bull can stand many things, but he cannot stand 2 per cent.”
Book VI
Short Notes Suggested by the General Theory
Chapter 22. Notes on the Trade Cycle
SINCE we claim to have shown in the preceding chapters what determines
the volume of employment at any time, it follows, if we are right, that
our theory must be capable of explaining the phenomena of the Trade
Cycle.
If we examine the details of any actual instance of the Trade
Cycle, we shall find that it is highly complex and that every element
in our analysis will be required for its complete explanation. In
particular we shall. find that fluctuations in the propensity to
consume, in the state of liquidity-preference, and in the marginal
efficiency of capital have all played a part. But I suggest that the
essential character of the Trade Cycle, and, especially, the regularity
of time-sequence and of duration which justifies us in calling it a
cycle, is mainly due to the way in which the marginal efficiency of
capital fluctuates. The Trade Cycle is best regarded, I think, as being
occasioned by a cyclical change in the marginal efficiency of capital,
though complicated. and often aggravated by associated changes in the
other significant short-period variables of the economic system. To
develop this thesis would occupy a book rather than a chapter, and
would require a close examination of facts. But the following short
notes will be sufficient to indicate the line of investigation which
our preceding theory suggests.
I
By a cyclical movement we mean that as the system progresses in, e.g.,
the upward direction, the forces propelling it upwards at first gather
force and have a cumulative effect on one another but gradually lose
their strength until at a certain point they tend to be replaced by
forces operating in the opposite direction; which in turn gather force
for a time and accentuate one another, until they too, having reached
their maximum development, wane and give place to their opposite. We do
not, however, merely mean by a cyclical movement that upward and
downward tendencies, once started, do not persist for ever in the same
direction but are ultimately reversed. We mean also that there is some
recognisable degree of regularity in the time sequence and duration of
the upward and downward movements.
There is, however, another characteristic of what we call the Trade
Cycle which our explanation must cover if it is to be adequate; namely,
the phenomenon of the crisis ― the fact that the substitution of a
downward for an upward tendency often takes place suddenly and
violently, whereas there is, as a rule, no such sharp turning-point
when an upward is substituted for a downward tendency.
Any fluctuation in investment not offset by a corresponding change in
the propensity to consume will, of course, result in a fluctuation in
employment. Since, therefore, the volume of investment is subject to
highly complex influences, it is highly improbable that all
fluctuations either in investment itself or in the marginal efficiency
of capital will be of a cyclical character. One special case, in
particular, namely, that which is associated with agricultural
fluctuations, will be separately considered in a later section of this
chapter. I suggest, however, that there are certain definite reasons
why, in the case of a typical industrial trade cycle in the
nineteenth-century environment, fluctuations in the marginal efficiency
of capital should have had cyclical characteristics. These reasons are
by no means unfamiliar either in themselves or as explanations of the
trade cycle. My only purpose here is to link them up with the preceding
theory.
II
I can best introduce what I have to say by beginning with the later stages of the boom and the onset of the “crisis”.
We have seen above that the marginal efficiency of capital[1] depends,
not only on the existing abundance or scarcity of capital-goods and the
current cost of production of capital-goods, but also on current
expectations as to the future yield of capital-goods. In the case of
durable assets it is, therefore, natural and reasonable that
expectations of the future should play a dominant part in determining
the scale on which new investment is deemed advisable. But, as we have
seen, the basis for such expectations is very precarious. Being based
on shifting and unreliable evidence, they are subject to sudden and
violent changes.
Now, we have been accustomed in explaining the “crisis” to lay stress
on the rising tendency of the rate of interest under the influence of
the increased demand for money both for trade and speculative purposes.
At times this factor may certainly play an aggravating and,
occasionally perhaps, an initiating part. But I suggest that a more
typical, and often the predominant, explanation of the crisis is, not
primarily a rise in the rate of interest, but a sudden collapse in the
marginal efficiency of capital.
The later stages of the boom are characterised by optimistic
expectations as to the future yield of capital-goods sufficiently
strong to offset their growing abundance and their rising costs of
production and, probably, a rise in the rate of interest also. It is of
the nature of organised investment markets, under the influence of
purchasers largely ignorant of what they are buying and of speculators
who are more concerned with forecasting the next shift of market
sentiment than with a reasonable estimate of the future yield of
capital-assets, that, when disillusion falls upon an over-optimistic
and over-bought market, it should fall with sudden and even
catastrophic force.[2] Moreover, the dismay and uncertainty as to the
future which accompanies a collapse in the marginal efficiency of
capital naturally precipitates a sharp increase in liquidity-preference
― and hence a rise in the rate of interest. Thus the fact that a
collapse in the marginal efficiency of capital tends to be associated
with a rise in the rate of interest may seriously aggravate the decline
in investment. But the essence of the situation is to be found,
nevertheless, in the collapse in the marginal efficiency of capital,
particularly in the case of those types of capital which have been
contributing most to the previous phase of heavy new investment.
Liquidity-preference, except those manifestations of it which are
associated with increasing trade and speculation, does not increase
until after the collapse in the marginal efficiency of capital.
It is this, indeed, which renders the slump so intractable.
Later on, a decline in the rate of interest will be a great aid to
recovery and, probably, a necessary condition of it. But, for the
moment, the collapse in the marginal efficiency of capital may be so
complete that no practicable reduction in the rate of interest will be
enough. If a reduction in the rate of interest was capable of proving
an effective remedy by itself, it might be possible to achieve a
recovery without the elapse of any considerable interval of time and by
means more or less directly under the control of the monetary
authority. But, in fact, this is not usually the case; and it is not so
easy to revive the marginal efficiency of capital, determined, as it
is, by the uncontrollable and disobedient psychology of the business
world. It is the return of confidence（確信）, to speak in ordinary
language, which is so insusceptible to control in an economy of
individualistic capitalism. This is the aspect of the slump which
bankers and business men have been right in emphasising, and which the
economists who have put their faith in a “purely monetary” remedy have
underestimated.
This brings me to my point. The explanation of the time-element in the
trade cycle, of the fact that an interval of time of a particular order
of magnitude must usually elapse before recovery begins, is to be
sought in the influences which govern the recovery of the marginal
efficiency of capital. There are reasons, given firstly by the length
of life of durable assets in relation to the normal rate of growth in a
given epoch, and secondly, by the carrying-costs of surplus stocks, why
the duration of the downward movement should have an order of magnitude
which is not fortuitous, which does not fluctuate between, say, one
year this time and ten years next time, but which shows some regularity
of habit between, let us say, three and five years.
Let us recur to what happens at the crisis. So long as the boom was
continuing, much of the new investment showed a not unsatisfactory
current yield. The disillusion comes because doubts suddenly arise
concerning the reliability（信頼性） of the prospective yield, perhaps
because the current yield shows signs of failing off, as the stock of
newly produced durable goods steadily increases. If current costs of
production are thought to be higher than they will be later on, that
will be a further reason for a fall in the marginal efficiency of
capital. Once doubt begins it spreads rapidly. Thus at the outset of
the slump there is probably much capital of which the marginal
efficiency has become negligible or even negative. But the interval of
time, which will have to elapse before the shortage of capital through
use, decay and obsolescence causes a sufficiently obvious scarcity to
increase the marginal efficiency, may be a somewhat stable function of
the average durability of capital in a given epoch. If the
characteristics of the epoch shift, the standard time-interval will
change. If, for example, we pass from a period of increasing population
into one of declining population, the characteristic phase of the cycle
will be lengthened. But we have in the above a substantial reason why
the duration of the slump should have a definite relationship to the
length of life of durable assets and to the normal rate of growth in a
given epoch.
The second stable time-factor is due to the carrying-costs of surplus
stocks which force their absorption within a certain period, neither
very short nor very long. The sudden cessation of new investment after
the crisis will probably lead to an accumulation of surplus stocks of
unfinished goods. The carrying-costs of these stocks will seldom be
less than 10 per cent. per annum. Thus the fall in their price needs to
be sufficient to bring about a restriction which provides for their
absorption within a period of, say, three to five years at the outside.
Now the process of absorbing the stocks represents negative investment,
which is a further deterrent to employment; and, when it is over, a
manifest relief will be experienced.
Moreover, the reduction in working capital, which is necessarily
attendant on the decline in output on the downward phase, represents a
further element of disinvestment, which may be large; and, once the
recession has begun, this exerts a strong cumulative influence in the
downward direction. In the earliest phase of a typical slump there will
probably be an investment in increasing stocks which helps to offset
disinvestment in working-capital; in the next phase there may be a
short period of disinvestment both in stocks and in working-capital;
after the lowest point has been passed there is likely to be a further
disinvestment in stocks which partially offsets reinvestment in
working-capital; and, finally, after the recovery is well on its way,
both factors will be simultaneously favourable to investment. It is
against this background that the additional and superimposed effects of
fluctuations of investment in durable goods must be examined. When a
decline in this type of investment has set a cyclical fluctuation in
motion there will be little encouragement to a recovery in such
investment until the cycle has partly run its course.[3]
Unfortunately a serious fall in the marginal efficiency of capital also
tends to affect adversely the propensity to consume. For it involves a
severe decline in the market value of Stock Exchange equities. Now, on
the class who take an active interest in their Stock Exchange
investments, especially if they are employing, borrowed funds, this
naturally exerts a very depressing influence. These people are,
perhaps, even more influenced in their readiness to spend by rises and
falls in the value of their investments than by the state of their
income. With a “stock-minded” public, as in the United States to-day, a
rising stock-market may be an almost essential condition of a
satisfactory propensity to consume; and this circumstance, generally
overlooked until lately, obviously serves to aggravate still further
the depressing effect of a decline in the marginal efficiency of
capital.
When once the recovery has been started, the manner in which it feeds
on itself and cumulates is obvious. But during the downward phase, when
both fixed capital and stocks of materials are for the time being
redundant and working-capital is being reduced, the schedule of the
marginal efficiency of capital may fall so low that it can scarcely be
corrected, so as to secure a satisfactory rate of new investment, by
any practicable reduction in the rate of interest. Thus with markets
organised and influenced as they are at present, the market estimation
of the marginal efficiency of capital may suffer such enormously wide
fluctuations that it cannot be sufficiently offset by corresponding
fluctuations in the rate of interest. Moreover, the corresponding
movements in the stock-market may, as we have seen above, depress the
propensity to consume just when it is most needed. In conditions of
laissez-faire the avoidance of wide fluctuations in employment may,
therefore, prove impossible without a far-reaching change in the
psychology of investment markets such as there is no reason to expect.
I conclude that the duty of ordering the current volume of investment
cannot safely be left in private hands.
III
The preceding analysis may appear to be in conformity with the view of
those who hold that over-investment is the characteristic of the boom,
that the avoidance of this over-investment is the only possible remedy
for the ensuing slump, and that, whilst for the reasons given above the
slump cannot be prevented by a low rate of interest, nevertheless the
boom can be avoided by a high rate of interest. There is, indeed, force
in the argument that a high rate of interest is much more effective
against a boom than a low rate of interest against a slump.
To infer these conclusions from the above would, however, misinterpret
my analysis; and would, according to my way of thinking, involve
serious error. For the term over-investment is ambiguous. It may refer
to investments which are destined to disappoint the expectations which
prompted them or for which there is no use in conditions of severe
unemployment, or it may indicate a state of affairs where every kind of
capital-goods is so abundant that there is no new investment which is
expected, even in conditions of full employment, to earn in the course
of its life more than its replacement cost. It is only the latter state
of affairs which is one of over-investment, strictly speaking, in the
sense that any further investment would be a sheer waste of
resources.[4] Moreover, even if over-investment in this sense was a
normal characteristic of the boom, the remedy would not lie in clapping
on a high rate of interest which would probably deter some useful
investments and might further diminish the propensity to consume, but
in taking drastic steps, by redistributing incomes or otherwise, to
stimulate the propensity to consume.
According to my analysis, however, it is only in the former sense that
the boom can be said to be characterised by over-investment. The
situation, which I am indicating as typical, is not one in which
capital is so abundant that the community as a whole has no reasonable
use for any more, but where investment is being made in conditions
which are unstable and cannot endure, because it is prompted by
expectations which are destined to disappointment.
It may, of course, be the case ― indeed it is likely to be ―
that the illusions of the boom cause particular types of capital-assets
to be produced in such excessive abundance that some part of the output
is, on any criterion, a waste of resources; ― which sometimes happens,
we may add, even when there is no boom. It leads, that is to say, to
misdirected investment. But over and above this it is an essential
characteristic of the boom that investments which will in fact yield,
say, 2 per cent. in conditions of full employment are made in the
expectation of a yield of, say, 6 per cent., and are valued
accordingly. When the disillusion comes, this expectation is replaced
by a contrary “error of pessimism”, with the result that the
investments, which would in fact yield 2 per cent. in conditions of
full employment, are expected to yield less than nothing; and the
resulting collapse of new investment then leads to a state of
unemployment in which the investments, which would have yielded 2 per
cent. in conditions of full employment, in fact yield less than
nothing. We reach a condition where there is a shortage of houses, but
where nevertheless no one can afford to live in the houses that there
are.
Thus the remedy for the boom is not a higher rate of interest but a
lower rate of interest![5] For that may enable the so-called boom to
last. The right remedy for the trade cycle is not to be found in
abolishing booms and thus keeping us permanently in a semi-slump; but
in abolishing slumps and thus keeping us permanently in a quasi-boom.
The boom which is destined to end in a slump is caused, therefore, by
the combination of a rate of interest, which in a correct state of
expectation would be too high for full employment, with a misguided
state of expectation which, so long as it lasts, prevents this rate of
interest from being in fact deterrent. A boom is a situation in which
over-optimism triumphs over a rate of interest which, in a cooler
light, would be seen to be excessive.
Except during the war, I doubt if we have any recent experience of a
boom so strong that it led to full employment. In the United States
employment was very satisfactory in 1928-29 on normal standards; but I
have seen no evidence of a shortage of labour, except, perhaps, in the
case of a few groups of highly specialised workers. Some “bottle-necks”
were reached, but output as a whole was still capable of further
expansion. Nor was there over-investment in the sense that the standard
and equipment of housing was so high that everyone, assuming full
employment, had all he wanted at a rate which would no more than cover
the replacement cost, without any allowance for interest, over the life
of the house; and that transport, public services and agricultural
improvement had been carried to a point where further additions could
not reasonably be expected to yield even their replacement cost. Quite
the contrary. It would be absurd to assert of the United States in 1929
the existence of over-investment in the strict sense. The true state of
affairs was of a different character. New investment during the
previous five years had been, indeed, on so enormous a scale in the
aggregate that the prospective yield of further additions was, coolly
considered, falling rapidly. Correct foresight would have brought down
the marginal efficiency of capital to an unprecedentedly low figure; so
that the “boom” could not have continued on a sound basis except with a
very low long-term rate of interest, and an avoidance of misdirected
investment in the particular directions which were in danger of being
over-exploited. In fact, the rate of interest was high enough to deter
new investment except in those particular directions which were under
the influence of speculative excitement and, therefore, in special
danger of being over-exploited; and a rate of interest, high enough to
overcome the speculative excitement, would have checked, at the same
time, every kind of reasonable new investment. Thus an increase in the
rate of interest, as a remedy for the state of affairs arising out of a
prolonged period of abnormally heavy new investment, belongs to the
species of remedy which cures the disease by killing the patient.
It is, indeed, very possible that the prolongation of
approximately full employment over a period of years would be
associated in countries so wealthy as Great Britain or the United
States with a volume of new investment, assuming the existing
propensity to consume, so great that it would eventually lead to a
state of full investment in the sense that an aggregate gross yield in
excess of replacement cost could no longer be expected on a reasonable
calculation from a further increment of durable goods of any type
whatever. Moreover, this situation might be reached comparatively soon
― say within twenty-five years or less. I must not be taken to deny
this, because I assert that a state of full investment in the strict
sense has never yet occurred, not even momentarily.
Furthermore, even if we were to suppose that contemporary booms are apt
to be associated with a momentary condition of full investment or
over-investment in the strict sense, it would still be absurd to regard
a higher rate of interest as the appropriate remedy. For in this event
the case of those who attribute the disease to under-consumption would
be wholly established. The remedy would lie in various measures
designed to increase the propensity to consume by the redistribution of
incomes or otherwise; so that a given level of employment would require
a smaller volume of current investment to support it.
IV
It may be convenient at this point to say a word about the
important schools of thought which maintain, from various points of
view, that the chronic tendency of contemporary societies to
under-employment is to be traced to under-consumption; ― that is to
say, to social practices and to a distribution of wealth which result
in a propensity to consume which is unduly low.
In existing conditions ― or, at least, in the conditions which
existed until lately ― where the volume of investment is unplanned and
uncontrolled, subject to the vagaries of the marginal efficiency of
capital as determined by the private judgment of individuals ignorant
or speculative, and to a long-term rate of interest which seldom or
never falls below a conventional level, these schools of thought are,
as guides to practical policy, undoubtedly in the right. For in such
conditions there is no other means of raising the average level of
employment to a more satisfactory level. If it is impracticable
materially to increase investment, obviously there is no means of
securing a higher level of employment except by increasing consumption.
Practically I only differ from these schools of thought in thinking
that they may lay a little too much emphasis on increased consumption
at a time when there is still much social advantage to be obtained from
increased investment. Theoretically, however, they are open to the
criticism of neglecting the fact that there are two ways to expand
output. Even if we were to decide that it would be better to increase
capital more slowly and to concentrate effort on increasing
consumption, we must decide this with open eyes, after well considering
the alternative. I am myself impressed by the great social advantages
of increasing the stock of capital until it ceases to be scarce. But
this is a practical judgment, not a theoretical imperative.
Moreover, I should readily concede that the wisest course is to advance
on both fronts at once. Whilst aiming at a socially controlled rate of
investment with a view to a progressive decline in the marginal
efficiency of capital, I should support at the same time all sorts of
policies for increasing the propensity to consume. For it is unlikely
that full employment can be maintained, whatever we may do about
investment, with the existing propensity to consume. There is room,
therefore, for both policies to operate together; ― to promote
investment and, at the same time, to promote consumption, not merely to
the level which with the existing propensity to consume would
correspond to the increased investment, but to a higher level still.
If ― to take round figures for the purpose of illustration ― the
average level of output of to-day is 15 per cent. below what it would
be with continuous full employment, and if 10 per cent. of this output
represents net investment and go per cent. of it consumption ― if,
furthermore, net investment would have to rise 50 per cent. in order to
secure full employment with the existing propensity to consume, so that
with full employment output would rise from 100 to 115, consumption
from go to 100 and net investment from 10 to 15: ― then we might aim,
perhaps, at so modifying the propensity to consume that with full
employment consumption would rise from go to 103 and net investment
from 10 to 12.
V
Another school of thought finds the solution of the trade cycle, not in
increasing either consumption or investment, but in diminishing the
supply of labour seeking employment; i.e. by redistributing the
existing volume of employment without increasing employment or output.
This seems to me to be a premature policy ― much more clearly so than
the plan of increasing consumption. A point comes where every
individual weighs the advantages of increased leisure against increased
income. But at present the evidence is, I think, strong that the great
majority of individuals would prefer increased income to increased
leisure; and I see no sufficient reason for compelling those who would
prefer more income to enjoy more leisure.
VI
It may appear extraordinary that a school of thought should
exist which finds the solution for the trade cycle in checking the boom
in its early stages by a higher rate of interest. The only line of
argument, along which any justification for this policy can be
discovered, is that put forward by Mr. D. H. Robertson, who assumes, in
effect, that full employment is an impracticable ideal and that the
best that we can hope for is a level of employment much more stable
than at present and averaging, perhaps, a little higher.
If we rule out major changes of policy affecting either the
control of investment or the propensity to consume, and assume, broadly
speaking, a continuance of the existing state of affairs, it is, I
think, arguable that a more advantageous average state of expectation
might result from a banking policy which always nipped in the bud an
incipient boom by a rate of interest high enough to deter even the most
misguided optimists. The disappointment of expectation, characteristic
of the slump, may lead to so much loss and waste that the average level
of useful investment might be higher if a deterrent is applied. It is
difficult to be sure whether or not this is correct on its own
assumptions; it is a matter for practical judgment where detailed
evidence is wanting. It may be that it overlooks the social advantage
which accrues from the increased consumption which attends even on
investment which proves to have been totally misdirected, so that even
such investment may be more beneficial than no investment at all.
Nevertheless, the most enlightened monetary control might find itself
in difficulties, faced with a boom of the 1929 type in America, and
armed with no other weapons than those possessed at that time by the
Federal Reserve System; and none of the alternatives within its power
might make much difference to the result. However this may be, such an
outlook seems to me to be dangerously and unnecessarily defeatist. It
recommends, or at least assumes, for permanent acceptance too much that
is defective in our existing economic scheme.
The austere view, which would employ a high rate of interest to check
at once any tendency in the level of employment to rise appreciably
above the average of, say, the previous decade, is, however, more
usually supported by arguments which have no foundation at all apart
from confusion of mind. It flows, in some cases, from the belief that
in a boom investment tends to outrun saving, and that a higher rate of
interest will restore equilibrium by checking investment on the one
hand and stimulating savings on the other. This implies that saving and
investment can be unequal, and has, therefore, no meaning until these
terms have been defined in some special sense. Or it is sometimes
suggested that the increased saving which accompanies increased
investment is undesirable and unjust because it is, as a rule, also
associated with rising prices. But if this were so, any upward change
in the existing level of output and employment is to be deprecated. For
the rise in prices is not essentially due to the increase in
investment; ― it is due to the fact that in the short period supply
price usually increases with increasing output, on account either of
the physical fact of diminishing return or of the tendency of the
cost-unit to rise in terms of money when output increases. If the
conditions were those of constant supply-price, there would, of course,
be no rise of prices; yet, all the same, increased saving would
accompany increased investment. It is the increased output which
produces the increased saving; and the rise of prices is, merely a
by-product of the increased output, which will occur equally if there
is no increased saving but, instead, an increased propensity to
consume. No one has a legitimate vested interest in being able to buy
at prices which are only low because output is low.
Or, again, the evil is supposed to creep in if the increased investment
has been promoted by a fall in the rate of interest engineered by an
increase in the quantity of money. Yet there is no special virtue in
the pre-existing rate of interest, and the new money is not “forced” on
anyone; ― it is created in order to satisfy the increased
liquidity-preference which corresponds to the lower rate of interest or
the increased volume of transactions, and it is held by those
individuals who prefer to hold money rather than to lend it at the
lower rate of interest. Or, once more, it is suggested that a boom is
characterised by “capital consumption”, which presumably means negative
net investment, i.e. by an excessive propensity to consume. Unless the
phenomena of the trade cycle have been confused with those of a flight
from the currency such as occurred during the post-war European
currency collapses, the evidence is wholly to the contrary. Moreover,
even if it were so, a reduction in the rate of interest would be a more
plausible remedy than a rise in the rate of interest for conditions of
under-investment. I can make no sense at all of these schools of
thought; except, perhaps, by supplying a tacit assumption that
aggregate output is incapable of change. But a theory which assumes
constant output is obviously not very serviceable for explaining the
trade cycle.
VII
In the earlier studies of the trade cycle, notably by Jevons, an
explanation was found in agricultural fluctuations due to the seasons,
rather than in the phenomena of industry. In the light of the above
theory this appears as an extremely plausible approach to the problem.
For even to-day fluctuation in the stocks of agricultural products as
between one year and another is one of the largest individual items
amongst the causes of changes in the rate of current investment; whilst
at the time when Jevons wrote ― and more particularly over the period
to which most of his statistics applied ― this factor must have far
outweighed all others.
Jevons's theory, that the trade cycle was primarily due to the
fluctuations in the bounty of the harvest, can be re-stated as follows.
When an exceptionally large harvest is gathered in, an important
addition is usually made to the quantity carried over into later years.
The proceeds of this addition are added to the current incomes of the
farmers and are treated by them as income; whereas the increased
carry-over involves no drain on the income-expenditure of other
sections of the community but is financed out of savings. That is to
say, the addition to the carry-over is an addition to current
investment. This conclusion is not invalidated even if prices fall
sharply. Similarly when there is a poor harvest, the carry-over is
drawn upon for current consumption, so that a corresponding part of the
income-expenditure of the consumers creates no current income for the
farmers. That is to say, what is taken from the carry-over involves a
corresponding reduction in current investment. Thus, if investment in
other directions is taken to be constant, the difference in aggregate
investment between a year in which there is a substantial addition to
the carry-over and a year in which there is a substantial subtraction
from it may be large; and in a community where agriculture is the
predominant industry it will be overwhelmingly large compared with any
other usual cause of investment fluctuations. Thus it is natural that
we should find the upward turning-point to be marked by bountiful
harvests and the downward turning-point by deficient harvests. The
further theory, that there are physical causes for a regular cycle of
good and bad harvests, is, of course, a different matter with which we
are not concerned here.
More recently, the theory has been advanced that it is bad harvests,
not good harvests, which are good for trade, either because bad
harvests make the population ready to work for a smaller real reward or
because the resulting redistribution of purchasing-power is held to be
favourable to consumption. Needless to say, it is not these theories
which I have in mind in the above description of harvest phenomena as
an explanation of the trade cycle.
The agricultural causes of fluctuation are, however, much less
important in the modern world for two reasons. In the first place
agricultural output is a much smaller proportion of total output. And
in the second place the development of a world market for most
agricultural products, drawing upon both hemispheres, leads to an
averaging out of the effects of good and bad seasons, the percentage
fluctuation in the amount of the world harvest being far less than the
percentage fluctuations in the harvests of individual countries. But in
old days, when a country was mainly dependent on its own harvest, it is
difficult to see any possible cause of fluctuations in investment,
except war, which was in any way comparable in magnitude with changes
in the carry-over of agricultural products.
Even to-day it is important to pay close attention to the part played
by changes in the stocks of raw materials, both agricultural and
mineral, in the determination of the rate of current investment. I
should attribute the slow rate of recovery from a slump, after the
turning-point has been reached, mainly to the deflationary effect of
the reduction of redundant stocks to a normal level. At first the
accumulation of stocks, which occurs after the boom has broken,
moderates the rate of the collapse; but we have to pay for this relief
later on in the damping-down of the subsequent rate of recovery.
Sometimes, indeed, the reduction of stocks may have to be virtually
completed before any measurable degree of recovery can be detected. For
a rate of investment in other directions, which is sufficient to
produce an upward movement when there is no current disinvestment in
stocks to set off against it, may be quite inadequate so long as such
disinvestment is still proceeding.
We have seen, I think, a signal example of this in the earlier phases
of America's “New Deal”. When President Roosevelt's substantial loan
expenditure began, stocks of all kinds ― and particularly of
agricultural products ― still stood at a very high level. The “New
Deal” partly consisted in a strenuous attempt to reduce these stocks ―
by curtailment of current output and in all sorts of ways. The
reduction of stocks to a normal level was a necessary process ― a phase
which had to be endured. But so long as it lasted, namely, about two
years, it constituted a substantial offset to the loan expenditure
which was being incurred in other directions. Only when it had been
completed was the way prepared for substantial recovery.
Recent American experience has also afforded good examples of the part
played by fluctuations in the stocks of finished and unfinished goods ―
“inventories” as it is becoming usual to call them ― in causing the
minor oscillations within the main movement of the Trade Cycle.
Manufacturers, setting industry in motion to provide for a scale of
consumption which is expected to prevail some months later, are apt to
make minor miscalculations, generally in the direction of running a
little ahead of the facts. When they discover their mistake they have
to contract for a short time to a level below that of current
consumption so as to allow for the absorption of the excess
inventories; and the difference of pace between running a little ahead
and dropping back again has proved sufficient in its effect on the
current rate of investment to display itself quite clearly against the
background of the excellently complete statistics now available in the
United States.
Author's Footnotes
[1]. It is often convenient in contexts where there is no room for
misunderstanding to write “the marginal efficiency of capital”, where
“the schedule of the marginal efficiency of capital” is meant.
[2]. I have shown above (Chapter 12) that, although the private
investor is seldom himself directly responsible for new investment,
nevertheless the entrepreneurs, who are directly responsible, will find
it financially advantageous, and often unavoidable, to fall in with the
ideas of the market, even though they themselves are better instructed.
[3]. Some part of the discussion in my Treatise on Money, Book IV, bears upon the above.
[4]. On certain assumptions, however, as to the distribution of the
propensity to consume through time, investment which yielded a negative
return might be advantageous in the sense that, for the community as a
whole, it would maximise satisfaction.
[5]. See below (p. 327) for some arguments which can be urged on the
other side. For, if we are precluded from making large changes in our
present methods, I should agree that to raise the rate of interest
during a boom may be, in conceivable circumstances, the lesser evil.
Book VI
Short Notes Suggested by the General Theory
Chapter 23.
Notes on Mercantilism) The Usury Laws, Stamped Money and Theories of Under-Consumption
I
FOR some two hundred years both economic theorists and practical men
did not doubt that there is a peculiar advantage to a country in a
favourable balance of trade, and grave danger in an unfavourable
balance, particularly if it results in an efflux of the precious
metals. But for the past one hundred years there has been a remarkable
divergence of opinion. The majority of statesmen and practical men in
most countries, and nearly half of them even in Great Britain, the home
of the opposite view, have remained faithful to the ancient doctrine;
whereas almost all economic theorists have held that anxiety concerning
such matters is absolutely groundless except on a very short view,
since the mechanism of foreign trade is self-adjusting and attempts to
interfere with it are not only futile, but greatly impoverish those who
practise them because they forfeit the advantages of the international
division of labour. It will be convenient, in accordance with
tradition, to designate the older opinion as Mercantilism and the newer
as Free Trade, though these terms, since each of them has both a
broader and a narrower signification, must be interpreted with
reference to the context.
Generally speaking, modern economists have maintained not merely that
there is, as a rule, a balance of gain from the international division
of labour sufficient to outweigh such advantages as mercantilist
practice can fairly claim, but that the mercantilist argument is based,
from start to finish, on an intellectual confusion.
Marshall,[1] for example, although his references to Mercantilism are
not altogether unsympathetic, had no regard for their central theory as
such and does not even mention those elements of truth in their
contentions which I shall examine below.[2] In the same way, the
theoretical concessions which free-trade economists have been ready to
make in contemporary controversies, relating, for example, to the
encouragement of infant industries or to the improvement of the terms
of trade, are not concerned with the real substance of the mercantilist
case. During the fiscal controversy of the first quarter of the present
century I do not remember that any concession was ever allowed by
economists to the claim that Protection might increase domestic
employment. It will be fairest, perhaps, to quote, as an example, what
I wrote myself. So lately as 1923, as a faithful pupil of the classical
school who did not at that time doubt what he had been taught and
entertained on this matter no reserves at all, I wrote: “If there is
one thing that Protection can not do, it is to cure Unemployment. ...
There are some arguments for Protection, based upon its securing
possible but improbable advantages, to which there is no simple answer.
But the claim to cure Unemployment involves the Protectionist fallacy
in its grossest and crudest form.”[3] As for earlier mercantilist
theory, no intelligible account was available; and we were brought up
to believe that it was little better than nonsense. So absolutely
overwhelming and complete has been the domination of the classical
school.
II
Let me first state in my own terms what now seems to me to be the
element of scientific truth in mercantilist doctrine. We will then
compare this with the actual arguments of the mercantilists. It should
be understood that the advantages claimed are avowedly national
advantages and are unlikely to benefit the world as a whole.
When a country is growing in wealth somewhat rapidly, the further
progress of this happy state of affairs is liable to be interrupted, in
conditions of laissez-faire, by the insufficiency of the inducements to
new investment. Given the social and political environment and the
national characteristics which determine the propensity to consume, the
well-being of a progressive state essentially depends, for the reasons
we have already explained, on the sufficiency of such inducements. They
may be found either in home investment or in foreign investment
(including in the latter the accumulation of the precious metals),
which, between them, make up aggregate investment. In conditions in
which the quantity of aggregate investment is determined by the profit
motive alone, the opportunities for home investment will be governed,
in the long run, by the domestic rate of interest; whilst the volume of
foreign investment is necessarily determined by the size of the
favourable balance of trade. Thus, in a society where there is no
question of direct investment under the aegis of public authority, the
economic objects, with which it is reasonable for the government to be
preoccupied, are the domestic rate of interest and the balance of
foreign trade.
Now, if the wage-unit is somewhat stable and not liable to spontaneous
changes of significant magnitude (a condition which is almost always
satisfied), if the state of liquidity-preference is somewhat stable,
taken as an average of its short-period fluctuations, and if banking
conventions are also stable, the rate of interest will tend to be
governed by the quantity of the precious metals, measured in terms of
the wage-unit, available to satisfy the community's desire for
liquidity. At the same time, in an age in which substantial foreign
loans and the outright ownership of wealth located abroad are scarcely
practicable, increases and decreases in the quantity of the precious
metals will largely depend on whether the balance of trade is
favourable or unfavourable.
Thus, as it happens, a preoccupation on the part of the authorities
with a favourable balance of trade served both purposes; and was,
furthermore, the only available means of promoting them. At a time when
the authorities had no direct control over the domestic rate of
interest or the other inducements to home investment, measures to
increase the favourable balance of trade were the only direct means at
their disposal for increasing foreign investment; and, at the same
time, the effect of a favourable balance of trade on the influx of the
precious metals was their only indirect means of reducing the domestic
rate of interest and so increasing the inducement to home investment.
There are, however, two limitations on the success of this policy which
must not be overlooked. If the domestic rate of interest falls so low
that the volume of investment is sufficiently stimulated to raise
employment to a level which breaks through some of the critical points
at which the wage-unit rises, the increase in the domestic level of
costs will begin to react unfavourably on the balance of foreign trade,
so that the effort to increase the latter will have overreached and
defeated itself. Again, if the domestic rate of interest falls so low
relatively to rates of interest elsewhere as to stimulate a volume of
foreign lending which is disproportionate to the favourable balance,
there may ensue an efflux of the precious metals sufficient to reverse
the advantages previously obtained. The risk of one or other of these
limitations becoming operative is increased in the case of a country
which is large and internationally important by the fact that, in
conditions where the current output of the precious metals from the
mines is on a relatively small scale, an influx of money into one
country means an efflux from another; so that the adverse effects of
rising costs and falling rates of interest at home may be accentuated
(if the mercantilist policy is pushed too far) by falling costs and
rising rates of interest abroad.
The economic history of Spain in the latter part of the fifteenth and
in the sixteenth centuries provides an example of a country whose
foreign trade was destroyed by the effect on the wage-unit of an
excessive abundance of the precious metals. Great Britain in the
pre-war years of the twentieth century provides an example of a country
in which the excessive facilities for foreign lending and the purchase
of properties abroad frequently stood in the way of the decline in the
domestic rate of interest which was required to ensure full employment
at home. The history of India at all times has provided an example of a
country impoverished by a preference for liquidity amounting to so
strong a passion that even an enormous and chronic influx of the
precious metals has been insufficient to bring down the rate of
interest to a level which was compatible with the growth of real wealth.
Nevertheless, if we contemplate a society with a somewhat stable
wage-unit, with national characteristics which determine the propensity
to consume and the preference for liquidity, and with a monetary system
which rigidly links the quantity of money to the stock of the precious
metals, it will be essential for the maintenance of prosperity that the
authorities should pay close attention to the state of the balance of
trade. For a favourable balance, provided it is not too large, will
prove extremely stimulating; whilst an unfavourable balance may soon
produce a state of persistent depression.
It does not follow from this that the maximum degree of
restriction of imports will promote the maximum favourable balance of
trade. The earlier mercantilists laid great emphasis on this and were
often to be found opposing trade restrictions because on a long view
they were liable to operate adversely to a favourable balance. It is,
indeed, arguable that in the special circumstances of
mid-nineteenth-century Great Britain an almost complete freedom of
trade was the policy most conducive to the development of a favourable
balance. Contemporary experience of trade restrictions in post-war
Europe offers manifold examples of ill-conceived impediments on freedom
which, designed to improve the favourable balance, had in fact a
contrary tendency.
For this and other reasons the reader must not reach a premature
conclusion as to the practical policy to which our argument leads up.
There are strong presumptions of a general character against trade
restrictions unless they can be justified on special grounds. The
advantages of the international division of labour are real and
substantial, even though the classical school greatly overstressed
them. The fact that the advantage which our own country gains from a
favourable balance is liable to involve an equal disadvantage to some
other country (a point to which the mercantilists were fully alive)
means not only that great moderation is necessary, so that a country
secures for itself no larger a share of the stock of the precious
metals than is fair and reasonable, but also that an immoderate policy
may lead to a senseless international competition for a favourable
balance which injures all alike.[4] And finally, a policy of trade
restrictions is a treacherous instrument even for the attainment of its
ostensible object, since private interest, administrative incompetence
and the intrinsic difficulty of the task may divert it into producing
results directly opposite to those intended.
Thus, the weight of my criticism is directed against the inadequacy of
the theoretical foundations of the laissez-faire doctrine upon which I
was brought up and which for many years I taught;― against the notion
that the rate of interest and the volume of investment are
self-adjusting at the optimum level, so that preoccupation with the
balance of trade is a waste of time. For we, the faculty of economists,
prove to have been guilty of presumptuous error in treating as a
puerile obsession what for centuries has been a prime object of
practical statecraft.
Under the influence of this faulty theory the City of London gradually
devised the most dangerous technique for the maintenance of equilibrium
which can possibly be imagined, namely, the technique of bank rate
coupled with a rigid parity of the foreign exchanges. For this meant
that the objective of maintaining a domestic rate of interest
consistent with full employment was wholly ruled out. Since, in
practice, it is impossible to neglect the balance of payments, a means
of controlling it was evolved which, instead of protecting the domestic
rate of interest, sacrificed it to the operation of blind forces.
Recently, practical bankers in London have learnt much, and one can
almost hope that in Great Britain the technique of bank rate will never
be used again to protect the foreign balance in conditions in which it
is likely to cause unemployment at home.
Regarded as the theory of the individual firm and of the distribution
of the product resulting from the employment of a given quantity of
resources, the classical theory has made a contribution to economic
thinking which cannot be impugned. It is impossible to think clearly on
the subject without this theory as a part of one's apparatus of
thought. I must not be supposed to question this in calling attention
to their neglect of what was valuable in their predecessors.
Nevertheless, as a contribution to statecraft, which is concerned with
the economic system as whole and with securing the optimum employment
of the system's entire resources, the methods of the early pioneers of
economic thinking in the sixteenth and seventeenth centuries may have
attained to fragments of practical wisdom which the unrealistic
abstractions of Ricardo first forgot and then obliterated. There was
wisdom in their intense preoccupation with keeping down the rate of
interest by means of usury laws (to which we will return later in this
chapter), by maintaining the domestic stock of money and by
discouraging rises in the wage-unit; and in their readiness in the last
resort to restore the stock of money by devaluation, if it had become
plainly deficient through an unavoidable foreign drain, a rise in the
wage-unit[5], or any other cause.
III
The early pioneers of economic thinking may have hit upon their maxims
of practical wisdom without having had much cognisance of the
underlying theoretical grounds. Let us, therefore, examine briefly the
reasons they gave as well as what they recommended. This is made easy
by reference to Professor Heckscher's great work on Mercantilism, in
which the essential characteristics of economic thought over a period
of two centuries are made available for the first time to the general
economic reader. The quotations which follow are mainly taken from his
pages.[6]
(1) Mercantilist thought never supposed that there was a self-adjusting
tendency by which the rate of interest would be established at the
appropriate level. On the contrary they were emphatic that an unduly
high rate of interest was the main obstacle to the growth of wealth;
and they were even aware that the rate of interest depended on
liquidity-preference and the quantity of money. They were concerned
both with diminishing liquidity-preference and with increasing the
quantity of money, and several of them made it clear that their
preoccupation with increasing the quantity of money was due to their
desire to diminish the rate of interest. Professor Heckscher sums up
this aspect of their theory as follows:
The position of the more perspicacious mercantilists was in this
respect, as in many others, perfectly clear within certain limits. For
them, money was ― to use the terminology of to-day ― a factor of
production, on the same footing as land, sometimes regarded as
“artificial” wealth as distinct from the “natural” wealth; interest on
capital was the payment for the renting of money similar to rent for
land. In so far as mercantilists sought to discover objective reasons
for the height of the rate of interest ― and they did so more and more
during this period ― they found such reasons in the total quantity of
money. From the abundant material available, only the most typical
examples will be selected, so as to demonstrate first and foremost how
lasting this notion was, how deep-rooted and independent of practical
considerations.
Both of the protagonists in the struggle over monetary policy and the
East India trade in the early 1620's in England were in entire
agreement on this point. Gerard Malynes stated, giving detailed reason
for his assertion, that “Plenty of money decreaseth usury in price or
rate” (Lex Mercatoria and Maintenance of Free Trade, 1622). His
truculent and rather unscrupulous adversary, Edward Misselden, replied
that “The remedy for Usury may be plenty of money” (Free Trade or the
Meanes to make Trade Florish, same year). Of the leading writers of
half a century later, Child, the omnipotent leader of the East India
Company and its most skilful advocate, discussed (1668) the question of
how far the legal maximum rate of interest, which he emphatically
demanded, would result in drawing “the money” of the Dutch away from
England. He found a remedy for this dreaded disadvantage in the easier
transference of bills of debt, if these were used as currency, for
this, he said, “will certainly supply the defect of at least one-half
of all the ready money we have in use in the nation”. Petty, the other
writer, who was entirely unaffected by the clash of interests, was in
agreement with the rest when he explained the “natural” fall in the
rate of interest from 10 per cent to 6 per cent by the increase in the
amount of money (Political Arithmetick, 1676), and advised lending at
interest as an appropriate remedy for a country with too much “Coin”
(Quantulumcunque concerning Money, 1682).
This reasoning, naturally enough, was by no means confined to England.
Several years later (1701 and 1706), for example, French merchants and
statesmen complained of the prevailing scarcity of coin (disette des
espe`ces) as the cause of the high interest rates, and they were
anxious to lower the rate of usury by increasing the circulation of
money.[7]
The great Locke was, perhaps, the first to express in abstract terms
the relationship between the rate of interest and the quantity of money
in his controversy with Petty.[8] He was opposing Petty's proposal of a
maximum rate of interest on the ground that it was as impracticable as
to fix a maximum rent for land, since “the natural Value of Money, as
it is apt to yield such an yearly Income by Interest, depends on the
whole quantity of the then passing Money of the Kingdom, in proportion
to the whole Trade of the Kingdom (i.e. the general Vent of all the
commodities)”.[9] Locke explains that Money has two values: (1) its
value in use which is given by the rate of interest “and in this it has
the Nature of Land, the Income of one being called Rent, of the other,
Use[10]”, and (2) its value in exchange “and in this it has the Nature
of a Commodity”, its value in exchange “depending only on the Plenty or
Scarcity of Money in proportion to the Plenty or Scarcity of those
things and not on what Interest shall be”. Thus Locke was the parent of
twin quantity theories. In the first place he held that the rate of
interest depended on the proportion of the quantity of money (allowing
for the velocity of circulation) to the total value of trade. In the
second place he held that the value of money in exchange depended on
the proportion of the quantity of money to the total volume of goods in
the market. But ― standing with one foot in the mercantilist world and
with one foot in the classical world[11] ― he was confused concerning
the relation between these two proportions, and he overlooked
altogether the possibility of fluctuations in liquidity-preference. He
was, however, eager to explain that a reduction in the rate of interest
has no direct effect on the price-level and affects prices “only as the
Change of Interest in Trade conduces to the bringing in or carrying out
Money or Commodity, and so in time varying their Proportion here in
England from what it was before”, i.e. if the reduction in the rate of
interest leads to the export of cash or an increase in output. But he
never, I think, proceeds to a genuine synthesis.[12]
How easily the mercantilist mind distinguished between the rate of
interest and the marginal efficiency of capital is illustrated by a
passage (printed in 1621) which Locke quotes from A Letter to a Friend
concerning Usury: “High Interest decays Trade. The advantage from
Interest is greater than the Profit from Trade, which makes the rich
Merchants give over, and put out their Stock to Interest, and the
lesser Merchants Break.” Fortrey (England's Interest and
Improvement（社会改良）, 1663) affords another example of the stress laid on
a low rate of interest as a means of increasing wealth.
The mercantilists did not overlook the point that, if an excessive
liquidity-preference were to withdraw the influx of precious metals
into hoards, the advantage to the rate of interest would be lost. In
some cases (e.g. Mun) the object of enhancing the power of the State
led them, nevertheless, to advocate the accumulation of state treasure.
But others frankly opposed this policy:
Schro"tter, for instance, employed the usual mercantilist arguments in
drawing a lurid picture of how the circulation in the country would be
robbed of all its money through a greatly increasing state treasury ...
he, too, drew a perfectly logical parallel between the accumulation of
treasure by the monasteries and the export surplus of precious metals,
which, to him, was indeed the worst possible thing which he could think
of. Davenant explained the extreme poverty of many Eastern nations ―
who were believed to have more gold and silver than any other countries
in the world ― by the fact that treasure “is suffered to stagnate in
the Princes' Coffers”. ... If hoarding by the state was considered, at
best, a doubtful boon, and often a great danger, it goes without saying
that private hoarding was to be shunned like the pest. It was one of
the tendencies against which innumerable mercantilist writers
thundered, and I do not think it would be possible to find a single
dissentient voice.[13]
(2) The mercantilists were aware of the fallacy of cheapness and the
danger that excessive competition may turn the terms of trade against a
country. Thus Malynes wrote in his Lex Mereatoria (1622): “Strive not
to undersell others to the hurt of the Commonwealth, under colour to
increase trade: for trade doth not increase when commodities are good
cheap, because the cheapness proceedeth of the small request and
scarcity of money, which maketh things cheap: so that the contrary
augmenteth trade, when there is plenty of money, and commodities become
dearer being in request”.[14] Professor Heckscher sums up as follows
this strand in mercantilist thought:
In the course of a century and a half the standpoint was
formulated again and again in this way, that a country with relatively
less money than other countries must “sell cheap and buy dear...”
Even in the original edition of the Discourse of the Common Weal, that
is in the middle of the 16th century, this attitude was already
manifested. Hales said, in fact, “And yet if strangers should be
content to take but our wares for theirs, what should let them to
advance the price of other things (meaning: among others, such as we
buy from them), though ours were good cheap unto them? And then shall
we be still losers, and they at the winning hand with us, while they
sell dear and yet buy ours good cheap, and consequently enrich
themselves and impoverish us. Yet had I rather advance our wares in
price, as they advance theirs, as we now do; though some be losers
thereby, and yet not so many as should be the other way.” On this point
he had the Unqualified approval of his editor several decades later
(1581). In the 17th century, this attitude recurred again without any
fundamental change in significance（根本的な変化がなく繰り返されている）. Thus, Malynes
believed this unfortunate position to be the result of what he dreaded
above all things, i.e. a foreign under-valuation of the English
exchange.... The same conception then recurred continually. In his
Verbum Sapienti (written 1665, published 1691), Petty believed that the
violent efforts to increase the quantity of money could only cease
“when we have certainly more money than any of our Neighbour States
(though never so little), both in Arithmetical and Geometrical
proportion”. During the period between the writing and the publication
of this work, Coke declared, “If our Treasure were more than our
Neighbouring Nations, I did not care whether we had one fifth part of
the Treasure we now have” (1675).[15]
(3) The mercantilists were the originals of “the fear of goods” and the
scarcity of money as causes of unemployment which the classicals were
to denounce two centuries later as an absurdity:
One of the earliest instances of the application of the Unemployment
argument as a reason for the prohibition of imports is to be found in
Florence in the year 1426.... The English legislation on the matter
goes back to at least 1455 .... An almost contemporary French decree of
1466, forming the basis of the silk industry of Lyons, later to become
so famous, was less interesting in so far as it was not actually
directed against foreign goods. But it, too, mentioned the possibility
of giving work to tens of thousands of unemployed men and women. It is
seen how very much this argument was in the air at the time...
The first great discussion of this matter, as of nearly all social and
economic problems, occurred in England in the middle of the 16th
century or rather earlier, during the reigns of Henry VIII and Edward
VI. In this connection we cannot but mention a series of writings,
written apparently at the latest in the 1530's, two of which at any
rate are believed to have been by Clement Armstrong.... He formulates
it, for example, in the following terms: “By reason of great abundance
of strange merchandises and wares brought yearly into England hath not
only caused scarcity of money, but hath destroyed all handicrafts,
whereby great number of common people should have works to get money to
pay for their meat and drink, which of very necessity must live idly
and beg and steal”
The best instance to my knowledge of a typically mercantilist
discussion of a state of affairs of this kind is the debates in the
English House of Commons concerning the scarcity of money, which
occurred in 1621, when a serious depression had set in, particularly in
the cloth export. The conditions were described very clearly by one of
the most influential members of parliament, Sir Edwin Sandys. He stated
that the farmer and the artificer had to suffer almost everywhere; that
looms were standing idle for want of money in the country, and that
peasants were forced to repudiate their contracts, “not (thanks be to
God) for want of fruits of the earth, but for want of money”. The
situation led to detailed enquiries into where the money could have got
to, the want of which was felt so bitterly. Numerous attacks were
directed against all persons who were supposed to have contributed
either to an export (export surplus) of precious metals, or to their
disappearance on account of corresponding activities within the
country.[17]
Mercantilists were conscious that their policy, as Professor Heckscher
puts it, “killed two birds with one stone”. “On the one hand the
country was rid of an unwelcome surplus of goods, which was believed to
result in unemployment, while on the other the total stock of money in
the country was increased”[18] with the resulting advantages of a fall
in the rate of interest.
It is impossible to study the notions to which the mercantilists
were led by their actual experiences, without perceiving that there has
been a chronic tendency throughout human history for the propensity to
save to be stronger than the inducement to invest. The weakness of the
inducement to invest has been at all times the key to the economic
problem. To-day the explanation of the weakness of this inducement may
chiefly lie in the extent of existing accumulations; whereas, formerly,
risks and hazards of all kinds may have played a larger part. But the
result is the same. The desire of the individual to augment his
personal wealth by abstaining from consumption has usually been
stronger than the inducement to the entrepreneur to augment the
national wealth by employing labour on the construction of durable
assets.
(4) The mercantilists were under no illusions as to the nationalistic
character of their policies and their tendency to promote war. It was
national advantage and relative strength at which they were admittedly
aiming.[19]
We may criticise them for the apparent indifference with which they
accepted this inevitable consequence of an international monetary
system. But intellectually their realism is much preferable to the
confused thinking of contemporary advocates of an international fixed
gold standard and laissez-faire in international lending, who believe
that it is precisely these policies which will best promote peace.
For in an economy subject to money contracts and customs more or less
fixed over an appreciable period of time, where the quantity of the
domestic circulation and the domestic rate of interest are primarily
determined by the balance of payments, as they were in Great Britain
before the war, there is no orthodox means open to the authorities for
countering unemployment at home except by struggling for an export
surplus and an import of the monetary metal at the expense of their
neighbours. Never in history was there a method devised of such
efficacy for setting each country's advantage at variance with its
neighbours' as the international gold (or, formerly, silver) standard.
For it made domestic prosperity directly dependent on a competitive
pursuit of markets and a competitive appetite for the precious metals.
When by happy accident the new supplies of gold and silver were
comparatively abundant, the struggle might be somewhat abated. But with
the growth of wealth and the diminishing marginal propensity to
consume, it has tended to become increasingly internecine. The part
played by orthodox economists, whose common sense has been insufficient
to check their faulty logic, has been disastrous to the latest act. For
when in their blind struggle for an escape, some countries have thrown
off the obligations which had previously rendered impossible an
autonomous rate of interest, these economists have taught that a
restoration of the former shackles is a necessary first step to a
general recovery.
In truth the opposite holds good. It is the policy of an
autonomous rate of interest, unimpeded by international preoccupations,
and of a national investment programme directed to an optimum level of
domestic employment which is twice blessed in the sense that it helps
ourselves and our neighbours at the same time. And it is the
simultaneous pursuit of these policies by all countries together which
is capable of restoring economic health and strength internationally,
whether we measure it by the level of domestic employment or by the
volume of international trade.[20]
IV
The mercantilists perceived the existence of the problem without being
able to push their analysis to the point of solving it. But the
classical school ignored the problem, as a consequence of introducing
into their premisses conditions which involved its non-existence; with
the result of creating a cleavage between the conclusions of economic
theory and those of common sense. The extraordinary achievement of the
classical theory was to overcome the beliefs of the “natural man” and,
at the same time, to be wrong. As Professor Heckscher expresses it:
If, then, the underlying attitude towards money and the material
from which money was created did not alter in the period between the
Crusades and the 18th century, it follows that we are dealing with
deep-rooted notions. Perhaps the same notions have persisted even
beyond the 500 years included in that period, even though not nearly to
the same degree as the “fear of goods”. ... With the exception of the
period of laissez-faire, no age has been free from these ideas. It was
only the unique intellectual tenacity of laissez-faire that for a time
overcame the beliefs of the “natural man” on this point.[21]
It required the unqualified faith of doctrinaire laissez-faire
to wipe out the “fear of goods” ... [which] is the most natural
attitude of the “natural man” in a money economy. Free Trade denied the
existence of factors which appeared to be obvious, and was doomed to be
discredited in the eyes of the man in the street as soon as
laissez-faire could no longer hold the minds of men enchained in its
ideology.[22]
I remember Bonar Law's mingled rage and perplexity in face of
the economists, because they were denying what was obvious. He was
deeply troubled for an explanation. One recurs to the analogy between
the sway of the classical school of economic theory and that of certain
religions. For it is a far greater exercise of the potency of an idea
to exorcise the obvious than to introduce into men's common notions the
recondite and the remote.
V
There remains an allied, but distinct, matter where for centuries,
indeed for several millenniums, enlightened opinion held for certain
and obvious a doctrine which the classical school has repudiated as
childish, but which deserves rehabilitation and honour. I mean the
doctrine that the rate of interest is not self-adjusting at a level
best suited to the social advantage but constantly tends to rise too
high, so that a wise Government is concerned to curb it by statute and
custom and even by invoking the sanctions of the moral law.
Provisions against usury are amongst the most ancient economic
practices of which we have record. The destruction of the inducement to
invest by an excessive liquidity-preference was the outstanding evil,
the prime impediment to the growth of wealth, in the ancient and
medieval worlds. And naturally so, since certain of the risks and
hazards of economic life diminish the marginal efficiency of capital
whilst others serve to increase the preference for liquidity. In a
world, therefore, which no one reckoned to be safe, it was almost
inevitable that the rate of interest, unless it was curbed by every
instrument at the disposal of society, would rise too high to permit of
an adequate inducement to invest.
I was brought up to believe that the attitude of the Medieval
Church to the rate of interest was inherently absurd, and that the
subtle discussions aimed at distinguishing the return on money-loans
from the return to active investment were merely Jesuitical attempts to
find a practical escape from a foolish theory. But I now read these
discussions as an honest intellectual effort to keep separate what the
classical theory has inextricably confused together, namely, the rate
of interest and the marginal efficiency of capital. For it now seems
clear that the disquisitions of the schoolmen were directed towards the
elucidation of a formula which should allow the schedule of the
marginal efficiency of capital to be high, whilst using rule and custom
and the moral law to keep down the rate of interest.
Even Adam Smith was extremely moderate in his attitude to the usury
laws. For he was well aware that individual savings may be absorbed
either by investment or by debts, and that there is no security that
they will find an outlet in the former. Furthermore, he favoured a low
rate of interest as increasing the chance of savings finding their
outlet in new investment rather than in debts; and for this reason, in
a passage for which he was severely taken to task by Bentham,[23] he
defended a moderate application of the usury laws.[24] Moreover,
Bentham's criticisms were mainly on the ground that Adam Smith's Scotch
caution was too severe on “projectors” and that a maximum rate of
interest would leave too little margin for the reward of legitimate and
socially advisable risks. For Bentham understood by projectors “all
such persons, as, in the pursuit of wealth, or even of any other
object, endeavour, by the assistance of wealth, to strike into any
channel of invention ... upon all such persons as, in the line of any
of their pursuits, aim at anything that can be called improvement（改良）.
... It falls, in short, upon every application of the human powers, in
which ingenuity stands in need of wealth for its assistance.” Of course
Bentham is right in protesting against laws which stand in the way of
taking legitimate risks. “A prudent man”, Bentham continues, “will not,
in these circumstances, pick out the good projects from the bad, for he
will not meddle with projects at all.”[25]
It may be doubted, perhaps, whether the above is just what Adam
Smith intended by his term. Or is it that we are hearing in Bentham
(though writing in March 1787 from “Crichoff in White Russia”) the
voice of nineteenth-century England speaking to the eighteenth? For
nothing short of the exuberance of the greatest age of the inducement
to investment could have made it possible to lose sight of the
theoretical possibility of its insufficiency.
VI
It is convenient to mention at this point the strange, unduly
neglected prophet Silvio Gesell (1862-1930), whose work contains
flashes of deep insight and who only just failed to reach down to the
essence of the matter. In the post-war years his devotees bombarded me
with copies of his works; yet, owing to certain palpable defects in the
argument, I entirely failed to discover their merit. As is often the
case with imperfectly analysed intuitions, their significance only
became apparent after I had reached my own conclusions in my own way.
Meanwhile, like other academic economists, I treated his profoundly
original strivings as being no better than those of a crank. Since few
of the readers of this book are likely to be well acquainted with the
significance of Gesell, I will give to him what would be otherwise a
disproportionate space.
Gesell was a successful German[26] merchant in Buenos Aires who was led
to the study of monetary problems by the crisis of the late 'eighties,
which was especially violent in the Argentine, his first work, Die
Reformation im Mu"nzwesen als Bru"cke zum socialen Staat, being
published in Buenos Aires in 1891. His fundamental ideas on money were
published in Buenos Aires in the same year under the title Nervus
rerum, and many books and pamphlets followed until he retired to
Switzerland in 1906 as a man of some means, able to devote the last
decades of his life to the two most delightful occupations open to
those who do not have to earn their living, authorship and experimental
farming.
The first section of his standard work was published in 1906 at Les
Hauts Geneveys, Switzerland, under the title Die Verwirklichung des
Rechtes auf dem vollen Arbeitsertrag, and the second section in 1911 at
Berlin under the title Die neue Lehre vom Zins. The two together were
published in Berlin and in Switzerland during the war (1916) and
reached a sixth edition during his lifetime under the title Die
natu"rliche Wirtschaftsordnung durch Freiland und Freigeld, the English
version (translated by Mr. Philip Pye) being called The Natural
Economic Order. In April 1919 Gesell joined the short-lived Soviet
cabinet of Bavaria as their Minister of Finance, being subsequently
tried by court-martial. The last decade of his life was spent in Berlin
and Switzerland and devoted to propaganda. Gesell, drawing to himself
the semi-religious fervour which had formerly centred round Henry
George, became the revered prophet of a cult with many thousand
disciples throughout the world. The first international convention of
the Swiss and German Freiland-Freigeld Bund and similar organisations
from many countries was held in Basle in 1923. Since his death in 1930
much of the peculiar type of fervour which doctrines such as his are
capable of exciting has been diverted to other (in my opinion less
eminent) prophets. Dr. Bu"chi is the leader of the movement in England,
but its literature seems to be distributed from San Antonio, Texas, its
main strength lying to-day in the United States, where Professor Irving
Fisher, alone amongst academic economists, has recognised its
significance.
In spite of the prophetic trappings with which his devotees have
decorated him, Gesell's main book is written in cool, scientific
language; though it is suffused throughout by a more passionate, a more
emotional devotion to social justice than some think decent in a
scientist. The part which derives from Henry George,[27] though
doubtless an important source of the movement's strength, is of
altogether secondary interest. The purpose of the book as a whole may
be described as the establishment of an anti-Marxian socialism, a
reaction against laissez-faire built on theoretical foundations totally
unlike those of Marx in being based on a repudiation instead of on an
acceptance of the classical hypotheses, and on an unfettering of
competition instead of its abolition. I believe that the future will
learn more from the spirit of Gesell than from that of Marx. The
preface to The Natural Economic Order will indicate to the reader, if
he will refer to it, the moral quality of Gesell. The answer to Marxism
is, I think, to be found along the lines of this preface.
Gesell's specific contribution to the theory of money and interest is
as follows. In the first place, he distinguishes clearly between the
rate of interest and the marginal efficiency of capital, and he argues
that it is the rate of interest which sets a limit to the rate of
growth of real capital. Next, he points out that the rate of interest
is a purely monetary phenomenon and that the peculiarity of money, from
which flows the significance of the money rate of interest, lies in the
fact that its ownership as a means of storing wealth involves the
holder in negligible carrying charges, and that forms of wealth, such
as stocks of commodities which do involve carrying charges, in fact
yield a return because of the standard set by money. He cites the
comparative stability of the rate of interest throughout the ages as
evidence that it cannot depend on purely physical characters, inasmuch
as the variation of the latter from one epoch to another must have been
incalculably greater than the observed changes in the rate of interest;
i.e. (in my terminology) the rate of interest, which depends on
constant psychological characters, has remained stable, whilst the
widely fluctuating characters, which primarily determine the schedule
of the marginal efficiency of capital, have determined not the rate of
interest but the rate at which the (more or less) given rate of
interest allows the stock of real capital to grow.
But there is a great defect in Gesell's theory. He shows how it is only
the existence of a rate of money interest which allows a yield to be
obtained from lending out stocks of commodities. His dialogue between
Robinson Crusoe and a stranger[28] is a most excellent economic parable
― as good as anything of the kind that has been written ― to
demonstrate this point. But, having given the reason why the money-rate
of interest unlike most commodity rates of interest cannot be negative,
he altogether overlooks the need of an explanation why the money-rate
of interest is positive, and he fails to explain why the money-rate of
interest is not governed (as the classical school maintains) by the
standard set by the yield on productive capital. This is because the
notion of liquidity-preference had escaped him. He has constructed only
half a theory of the rate of interest.
The incompleteness of his theory is doubtless the explanation of his
work having suffered neglect at the hands of the academic world.
Nevertheless he had carried his theory far enough to lead him to a
practical recommendation, which may carry with it the essence of what
is needed, though it is not feasible in the form in which he proposed
it. He argues that the growth of real capital is held back by the
money-rate of interest, and that if this brake were removed the growth
of real capital would be, in the modern world, so rapid that a zero
money-rate of interest would probably be justified, not indeed
forthwith, but within a comparatively short period of time. Thus the
prime necessity is to reduce the money-rate of interest, and this, he
pointed out, can be effected by causing money to incur carrying-costs
just like other stocks of barren goods. This led him to the famous
prescription of “stamped” money, with which his name is chiefly
associated and which has received the blessing of Professor Irving
Fisher. According to this proposal currency notes (though it would
clearly need to apply as well to some forms at least of bank-money)
would only retain their value by being stamped each month, like an
insurance card, with stamps purchased at a post office. The cost of the
stamps could, of course, be fixed at any appropriate figure. According
to my theory it should be roughly equal to the excess of the money-rate
of interest (apart from the stamps) over the marginal efficiency of
capital corresponding to a rate of new investment compatible with full
employment. The actual charge suggested by Gesell was 1 per mil. per
month, equivalent to 5.4 per cent. per annum. This would be too high in
existing conditions, but the correct figure, which would have to be
changed from time to time, could only be reached by trial and error.
The idea behind stamped money is sound. It is, indeed, possible that
means might be found to apply it in practice on a modest scale. But
there are many difficulties which Gesell did not face. In particular,
he was unaware that money was not unique in having a liquidity-premium
attached to it, but differed only in degree from many other articles,
deriving its importance from having a greater liquidity-premium than
any other article. Thus if currency notes were to be deprived of their
liquidity-premium by the stamping system, a long series of substitutes
would step into their shoes ― bank-money, debts at call, foreign money,
jewellery and the precious metals generally, and so forth. As I have
mentioned above, there have been times when it was probably the craving
for the ownership of land, independently of its yield, which served to
keep up the rate of interest; ― though under Gesell's system this
possibility would have been eliminated by land nationalisation.
VII
The theories which we have examined above are directed, in substance,
to the constituent of effective demand which depends on the sufficiency
of the inducement to invest. It is no new thing, however, to ascribe
the evils of unemployment to the insufficiency of the other
constituent, namely, the insufficiency of the propensity to consume.
But this alternative explanation of the economic evils of the day ―
equally unpopular with the classical economists ― played a much smaller
part in sixteenth- and seventeenth-century thinking and has only
gathered force in comparatively recent times.
Though complaints of under-consumption were a very subsidiary aspect of
mercantilist thought, Professor Heckscher quotes a number of examples
of what he calls “the deep-rooted belief in the utility of luxury and
the evil of thrift. Thrift, in fact, was regarded as the cause of
unemployment, and for two reasons: in the first place, because real
income was believed to diminish by the amount of money which did not
enter into exchange, and secondly, because saving was believed to
withdraw money from circulation."[29] In 1598 Laffemas (Les Tre'sors et
richesses pour mettre l'Estat en Splendeur) denounced the objectors to
the use of French silks on the ground that all purchasers of French
luxury goods created a livelihood for the poor, whereas the miser
caused them to die in distress.[30] In 1662 Petty justified
“entertainments, magnificent shews, triumphal arches, etc.”, on the
ground that their costs flowed back into the pockets of brewers,
bakers, tailors, shoemakers and so forth. Fortrey justified “excess of
apparel”. Von Schro"tter (1686) deprecated sumptuary regulations and
declared that he would wish that display in clothing and the like were
even greater. Barbon (1690) wrote that “Prodigality is a vice that is
prejudicial to the Man, but not to trade. ... Covetousness is a Vice,
prejudicial both to Man and Trade.” [31] In 1695 Cary argued that if
everybody spent more, all would obtain larger incomes “and might then
live more plentifully”.[32]
But it was by Bernard Mandeville's Fable of the Bees that Barbon's
opinion was mainly popularised, a book convicted as a nuisance by the
grand jury of Middlesex in 1723, which stands out in the history of the
moral sciences for its scandalous reputation. Only one man is recorded
as having spoken a good word for it, namely Dr. Johnson, who declared
that it did not puzzle him, but “opened his eyes into real life very
much”. The nature of the book's wickedness can be best conveyed by
Leslie Stephen's summary in the Dictionary of National Biography:
Mandeville gave great offence by this book, in which a cynical system
of morality was made attractive by ingenious paradoxes. ... His
doctrine that prosperity was increased by expenditure rather than by
saving fell in with many current economic fallacies not yet
extinct.[33] Assuming with the ascetics that human desires were
essentially evil and therefore produced “private vices” and assuming
with the common view that wealth was a “public benefit”, he easily
showed that all civilisation implied the development of vicious
propensities....
The text of the Fable of the Bees is an allegorical poem ― “The
Grumbling Hive, or Knaves turned honest”, in which is set forth the
appalling plight of a prosperous community in which all the citizens
suddenly take it into their heads to abandon luxurious living, and the
State to cut down armaments, in the interests of Saving:
No Honour now could be content,
To live and owe for what was spent,
Liv'ries in Broker's shops are hung;
They part with Coaches for a song;
Sell stately Horses by whole sets;
And Country-Houses to pay debts.
Vain cost is shunn'd as moral Fraud;
They have no Forces kept Abroad;
Laugh at th' Esteem of Foreigners,
And empty Glory got by Wars;
They fight, but for their Country's sake,
When Right or Liberty's at Stake.
The haughty Chloe
Contracts th' expensive Bill of Fare,
And wears her strong Suit a whole Year.
And what is the result? ―
Now mind the glorious Hive, and see
How Honesty and Trade agree:
The Shew is gone, it thins apace;
And looks with quite another Face,
For 'twas not only they that went,
By whom vast sums were yearly spent;
But Multitudes that lived on them,
Were daily forc'd to do the same.
In vain to other Trades they'd fly;
All were o'er-stocked accordingly.
The price of Land and Houses falls;
Mirac'lous Palaces whose Walls,
Like those of Thebes, were rais'd by Play,
Are to be let ...
The Building Trade is quite destroy'd,
Artificers are not employ'd;
No limner for his Art is fam'd,
Stone-cutters, Carvers are not nam'd.
So “The Moral” is:
are Virtue can't make Nations live
In Splendour. They that would revive
A Golden Age, must be as free,
For Acorns as for Honesty.
Two extracts from the commentary which follows the allegory will show that the above was not without a theoretical basis:
As this prudent economy, which some people call Saving, is in private
families the most certain method to increase an estate, so some imagine
that, whether a country be barren or fruitful, the same method if
generally pursued (which they think practicable) will have the same
effect upon a whole nation, and that, for example, the English might be
much richer than they are, if they would be as frugal as some of their
neighbours. This, I think, is an error.[34]
On the contrary, Mandeville concludes:
The great art to make a nation happy, and what we call flourishing,
consists in giving everybody an opportunity of being employed; which to
compass, let a Government's first care be to promote as great a variety
of Manufactures, Arts and Handicrafts as human wit can invent; and the
second to encourage Agriculture and Fishery in all their branches, that
the whole Earth may be forced to exert itself as well as Man. It is
from this Policy and not from the trifling regulations of Lavishness
and Frugality that the greatness and felicity of Nations must be
expected; for let the value of Gold and Silver rise or fall, the
enjoyment of all Societies will ever depend upon the Fruits of the
Earth and the Labour of the People; both which joined together are a
more certain, a more inexhaustible and a more real Treasure than the
Gold of Brazil or the Silver of Potosi.
No wonder that such wicked sentiments called down the opprobrium of two
centuries of moralists and economists who felt much more virtuous in
possession of their austere doctrine that no sound remedy was
discoverable except in the utmost of thrift and economy both by the
individual and by the state. Petty's “entertainments, magnificent
shews, triumphal arches, etc.” gave place to the penny-wisdom of
Gladstonian finance and to a state system which “could not afford”
hospitals, open spaces, noble buildings, even the preservation of its
ancient monuments, far less the splendours of music and the drama, all
of which were consigned to the private charity or magnanimity of
improvident individuals.
The doctrine did not reappear in respectable circles for another
century, until in the later phase of Malthus the notion of the
insufficiency of effective demand takes a definite place as a
scientific explanation of unemployment. Since I have already dealt with
this somewhat fully in my essay on Malthus,[35] it will be sufficient
if I repeat here one or two characteristic passages which I have
already quoted in my essay:
We see in almost every part of the world vast powers of production
which are not put into action, and I explain this phenomenon by saying
that from the want of a proper distribution of the actual produce
adequate motives are not furnished to continued production. ... I
distinctly maintain that an attempt to accumulate very rapidly, which
necessarily implies a considerable diminution of unproductive
consumption, by greatly impairing the usual motives to production must
prematurely check the progress of wealth. ... But if it be true that an
attempt to accumulate very rapidly will occasion such a division
between labour and profits as almost to destroy both the motive and the
power of future accumulation and consequently the power of maintaining
and employing an increasing population, must it not be acknowledged
that such an attempt to accumulate, or that saving too much, may be
really prejudicial to a country? [36]
The question is whether this stagnation of capital, and subsequent
stagnation in the demand for labour arising from increased production
without an adequate proportion of unproductive consumption on the part
of the landlords and capitalists, could take place without prejudice to
the country, without occasioning a less degree both of happiness and
wealth than would have occurred if the unproductive consumption of the
landlords and capitalists had been so proportioned to the natural
surplus of the society as to have continued uninterrupted the motives
to production, and prevented first an unnatural demand for labour and
then a necessary and sudden diminution of such demand. But if this be
so, how can it be said with truth that parsimony, though it may be
prejudicial to the producers, cannot be prejudicial to the state; or
that an increase of unproductive consumption among landlords and
capitalists may not sometimes be the proper remedy for a state of
things in which the motives to production fails?[37]
Adam Smith has stated that capitals are increased by parsimony, that
every frugal man is a public benefactor, and that the increase of
wealth depends upon the balance of produce above consumption. That
these propositions are true to a great extent is perfectly
unquestionable. ... But it is quite obvious that they are not true to
an indefinite extent, and that the principles of saving, pushed to
excess, would destroy the motive to production. If every person were
satisfied with the simplest food, the poorest clothing and the meanest
houses, it is certain that no other sort of food, clothing, and lodging
would be in existence. ... The two extremes are obvious; and it follows
that there must be some intermediate point, though the resources of
political economy may not be able to ascertain it, where, taking into
consideration both the power to produce and the will to consume, the
encouragement to the increase of wealth is the greatest.[38]
Of all the opinions advanced by able and ingenious men, which I have
ever met with, the opinion of M. Say, which states that: un product
consomme' ou de'truit est un de'bouche' ferme' (I. i. ch. 15), appears
to me to be the most directly opposed to just theory, and the most
uniformly contradicted by experience. Yet it directly follows from the
new doctrine, that commodities are to be considered only in their
relation to each other, ― not to the consumers. What, I would ask,
would become of the demand for commodities, if all consumption except
bread and water were suspended for the next half-year? What an
accumulation of commodities! Quels de'bouche's! What a prodigious
market would this event occasion![39]
Ricardo, however, was stone-deaf to what Malthus was saying. The last
echo of the controversy is to be found in John Stuart Mill's discussion
of his Wages-Fund Theory, [40] which in his own mind played a vital
part in his rejection of the later phase of Malthus, amidst the
discussions of which he had, of course, been brought up. Mill's
successors rejected his Wages-Fund Theory but overlooked the fact that
Mill's refutation of Malthus depended on it. Their method was to
dismiss the problem from the corpus of Economics not by solving it but
by not mentioning it. It altogether disappeared from controversy. Mr.
Cairncross, searching recently for traces of it amongst the minor
Victorians, [41] has found even less, perhaps, than might have been
expected. [42] Theories of under-consumption hibernated until the
appearance in 1889 of The Physiology of Industry, by J. A. Hobson and
A. F. Mummery, the first and most significant of many volumes in which
for nearly fifty years Mr. Hobson has flung himself with unflagging,
but almost unavailing, ardour and courage against the ranks of
orthodoxy. Though it is so completely forgotten to-day, the publication
of this book marks, in a sense, an epoch in economic thought.[43]
The Physiology of Industry was written in collaboration with A. F.
Mummery. Mr. Hobson has told how the book came to be written as
follows: [44]
It was not until the middle 'eighties that my economic
heterodoxy began to take shape. Though the Henry George campaign
against land values and the early agitation of various socialist groups
against the visible oppression of the working classes, coupled with the
revelations of the two Booths regarding the poverty of London, made a
deep impression on my feelings, they did not destroy my faith in
Political Economy. That came from what may be called an accidental
contact. While teaching at a school in Exeter I came into personal
relations with a business man named Mummery, known then and afterwards
as a great mountaineer who had discovered another way up the Matterhorn
and who, in 1895, was killed in an attempt to climb the famous
Himalayan mountain Nanga Parbat. My intercourse with him, I need hardly
say did not lie on this physical plane. But he was a mental climber as
well, with a natural eye for a path of his own finding and a sublime
disregard of intellectual authority. This man entangled me in a
controversy about excessive saving, which he regarded as responsible
for the under-employment of capital and labour in periods of bad trade.
For a long time I sought to counter his arguments by the use of the
orthodox economic weapons. But at length he convinced me and I went in
with him to elaborate the over-saving argument in a book entitled The
Physiology of Industry, which was published in 1889. This was the first
open step in my heretical career, and I did not in the least realise
its momentous consequences. For just at that time I had given up my
scholastic post and was opening a new line of work as University
Extension Lecturer in Economics and Literature. The first shock came in
a refusal of the London Extension Board to allow me to offer courses of
Political Economy. This was due, I learned, to the intervention of an
Economic Professor who had read my book and considered it as equivalent
in rationality to an attempt to prove the flatness of the earth. How
could there be any limit to the amount of useful saving when every item
of saving went to increase the capital structure and the fund for
paying wages? Sound economists could not fail to view with horror an
argument which sought to check the source of all industrial
progress.[45] Another interesting personal experience helped to bring
home to me the sense of my iniquity. Though prevented from lecturing on
economics in London, I had been allowed by the greater liberality of
the Oxford University Extension Movement to address audiences in the
Provinces, confining myself to practical issues relating to
working-class life. Now it happened at this time that the Charity
Organisation Society was planning a lecture campaign upon economic
subjects and invited me to prepare a course. I had expressed a
willingness to undertake this new lecture work, when suddenly, without
explanation, the invitation was withdrawn. Even then I hardly realised
that in appearing to question the virtue of unlimited thrift I had
committed the unpardonable sin.
In this early work Mr. Hobson with his collaborator expressed
himself with more direct reference to the classical economics (in which
he had been brought up) than in his later writings; and for this
reason, as well as because it is the first expression of his theory, I
will quote from it to show how significant and well-founded were the
authors' criticisms and intuitions. They point out in their preface as
follows the nature of the conclusions which they attack:
Saving enriches and spending impoverishes the community along with the
individual, and it may be generally defined as an assertion that the
effective love of money is the root of all economic good. Not merely
does it enrich the thrifty individual himself, but it raises wages,
gives work to the unemployed, and scatters blessings on every side.
From the daily papers to the latest economic treatise, from the pulpit
to the House of Commons, this conclusion is reiterated and re-stated
till it appears positively impious to question it. Yet the educated
world, supported by the majority of economic thinkers, up to the
publication of Ricardo's work strenuously denied this doctrine, and its
ultimate acceptance was exclusively due to their inability to meet the
now exploded wages-fund doctrine. That the conclusion should have
survived the argument on which it logically stood, can be explained on
no other hypothesis than the commanding authority of the great men who
asserted it. Economic critics have ventured to attack the theory in
detail, but they have shrunk appalled from touching its main
conclusions. Our purpose is to show that these conclusions are not
tenable, that an undue exercise of the habit of saving is possible, and
that such undue exercise impoverishes the Community, throws labourers
out of work, drives down wages, and spreads that gloom and prostration
through the commercial world which is known as Depression in Trade. ...
The object of production is to provide “utilities and conveniences” for
consumers, and the process is a continuous one from the first handling
of the raw material to the moment when it is finally consumed as a
utility or a convenience. The only use of Capital being to aid the
production of these utilities and conveniences, the total used will
necessarily vary with the total of utilities and conveniences daily or
weekly consumed. Now saving, while it increases the existing aggregate
of Capital, simultaneously reduces the quantity of utilities and
conveniences consumed; any undue exercise of this habit must,
therefore, cause an accumulation of Capital in excess of that which is
required for use, and this excess will exist in the form of general
over-production.[46]
In the last sentence of this passage there appears the root of
Hobson's mistake, namely, his supposing that it is a case of excessive
saving causing the actual accumulation of capital in excess of what is
required, which is, in fact, a secondary evil which only occurs through
mistakes of foresight; whereas the primary evil is a propensity to save
in conditions of full employment more than the equivalent of the
capital which is required, thus preventing full employment except when
there is a mistake of foresight. A page or two later, however, he puts
one half of the matter, as it seems to me, with absolute precision,
though still overlooking the possible role of changes in the rate of
interest and in the state of business confidence, factors which he
presumably takes as given:
We are thus brought to the conclusion that the basis on which all
economic teaching since Adam Smith has stood, viz. that the quantity
annually produced is determined by the aggregates of Natural Agents,
Capital, and Labour available, is erroneous, and that, on the contrary,
the quantity produced, while it can never exceed the limits imposed by
these aggregates, may be, and actually is, reduced far below this
maximum by the check that undue saving and the consequent accumulation
of over-supply exerts on production; i.e. that in the normal state of
modern industrial Communities, consumption limits production and not
production consumption.[47]
Finally he notices the bearing of his theory on the validity of the orthodox Free Trade arguments:
We also note that the charge of commercial imbecility, so freely
launched by orthodox economists against our American cousins and other
Protectionist Communities, can no longer be maintained by any of the
Free Trade arguments hitherto adduced, since all these are based on the
assumption that over-supply is impossible.[48]
The subsequent argument is, admittedly, incomplete. But it is the first
explicit statement of the fact that capital is brought into existence
not by the propensity to save but in response to the demand resulting
from actual and prospective consumption. The following portmanteau
quotation indicates the line of thought:
It should be clear that the capital of a community cannot be
advantageously increased without a subsequent increase in consumption
of commodities. ... Every increase in saving and in capital requires,
in order to be effectual, a corresponding increase in immediately
future consumption.[49] ... And when we say future consumption, we do
not refer to a future of ten, twenty, or fifty years hence, but to a
future that is but little removed he present. ... If increased thrift
or caution induces people to save more in the present, they must
consent to consume more in the future.[50] ... No more capital can
economically exist at any point in the productive process than is
required to furnish commodities for the current rate of
consumption.[51] ... It is clear that my thrift in no wise affects the
total economic thrift of the community, but only determines whether a
particular portion of the total thrift shall have been exercised by
myself or by somebody else. We shall show how the thrift of one part of
the community has power to force another part to live beyond their
income.[52] ... Most modern economists deny that consumption could by
any possibility be insufficient. Can we find any economic force at work
which might incite a community to this excess, and if there be any such
forces are there not efficient checks provided by the mechanism of
commerce? It will be shown, firstly, that in every highly organised
industrial society there is constantly at work a force which naturally
operates to induce excess of thrift; secondly, that the checks alleged
to be provided by the mechanism of commerce are either wholly
inoperative or are inadequate to prevent grave commercial evil.[53] ...
The brief answer which Ricardo gave to the contentions of Malthus and
Chalmers seems to have been accepted as sufficient by most later
economists. “Productions are always bought by productions or by
services; money is only the medium by which the exchange is effected.
Hence the increased production being always accompanied by a
correspondingly increased ability to get and consume, there is no
possibility of Overproduction” (Ricardo, Prin. of Pol. Econ. p.
362).[54]
Hobson and Mummery were aware that interest was nothing whatever except
payment for the use of money.[55] They also knew well enough that their
opponents would claim that there would be “such a fall in the rate of
interest (or profit) as will act as a check upon Saving, and restore
the proper relation between production and consumption”.[56] They point
out in reply that “if a fall of Profit is to induce people to save
less, it must operate in one of two ways, either by inducing them to
spend more or by inducing them to produce less”.[57] As regards the
former they argue that when profits fall the aggregate income of the
community is reduced, and “we cannot suppose that when the average rate
of incomes is falling, individuals will be induced to increase their
rate of consumption by the fact that the premium upon thrift is
correspondingly diminished”; whilst as for the second alternative, “it
is so far from being our intention to deny that a fall of profit, due
to over-supply, will check production, that the admission of the
operation of this check forms the very centre of our argument”.[58]
Nevertheless, their theory failed of completeness, essentially on
account of their having no independent theory of the rate of interest;
with the result that Mr. Hobson laid too much emphasis (especially in
his later books) on under-consumption leading to over-investment, in
the sense of unprofitable investment, instead of explaining that a
relatively weak propensity to consume helps to cause unemployment by
requiring and not receiving the accompaniment of a compensating volume
of new investment, which, even if it may sometimes occur temporarily
through errors of optimism, is in general prevented from happening at
all by the prospective profit falling below the standard set by the
rate of interest.
Since the war there has been a spate of heretical theories of
under-consumption, of which those of Major Douglas are the most famous.
The strength of Major Douglas's advocacy has, of course, largely
depended on orthodoxy having no valid reply to much of his destructive
criticism. On the other hand, the detail of his diagnosis, in
particular the so-called A + B theorem, includes much mere
mystification. If Major Douglas had limited his B-items to the
financial provisions made by entrepreneurs to which no current
expenditure on replacements and renewals corresponds, he would be
nearer the truth. But even in that case it is necessary to allow for
the possibility of these provisions being offset by new investment in
other directions as well as by increased expenditure on consumption.
Major Douglas is entitled to claim, as against some of his orthodox
adversaries, that he at least has not been wholly oblivious of the
outstanding problem of our economic system. Yet he has scarcely
established an equal claim to rank ― a private, perhaps, but not a
major in the brave army of heretics ― with Mandeville, Malthus, Gesell
and Hobson, who, following their intuitions, have preferred to see the
truth obscurely and imperfectly rather than to maintain error, reached
indeed with clearness and consistency and by easy logic, but on
hypotheses inappropriate to the facts.
Author's Footnotes
[1]. Vide his Industry and Trade, Appendix D; Money, Credit and Commerce, p. 130; and Principles of Economics, Appendix I.
[2]. His view of them is well summed up in a footnote to the first
edition of his Principles, p. 51: “Much study has been given both in
England and Germany to medieval opinions as to the relation of money to
national wealth. On the whole they are to be regarded as confused
through want of a clear understanding of the functions of money, rather
than as wrong in consequence of a deliberate assumption that the
increase in the net wealth of a nation can be effected only by an
increase of the stores of the precious metals in her.”
[3]. The Nation and the Athenaeum, November 24, 1923.
[4]. The remedy of an elastic wage-unit, so that a depression is met by
a reduction of wages, is liable, for the same reason, to be a means of
benefiting ourselves at the expense of our neighbours.
[5]. Experience since the age of Solon at least, and probably, if we
had the statistics, for many centuries before that, indicates what a
knowledge of human nature would lead us to expect, namely, that there
is a steady tendency for the wage-unit to rise over long periods of
time and that it can be reduced only amidst the decay and dissolution
of economic society. Thus, apart altogether from progress and
increasing population, a gradually increasing stock of money has proved
imperative.
[6]. They are the more suitable for my purpose because Prof. Heckscher
is himself an adherent, on the whole, of the classical theory and much
less sympathetic to the mercantilist theories than I am. Thus there is
no risk that his choice of quotations has been biased in any way by a
desire to illustrate their wisdom.
[7]. Heckscher, Mercantilism, vol. ii. pp. 200, 201, very slightly abridged.
[8]. Some Considerations of the Consequences of the Lowering of
Interest and Raising the Value of Money, 1692, but written some years
previously.
[9]. He adds: “not barely on the quantity of money but the quickness of its circulation”.
[10]. “Use” being, of course, old-fashioned English for “interest”.
[11]. Hume a little later had a foot and a half in the classical world.
For Hume began the practice amongst economists of stressing the
importance of the equilibrium position as compared with the
ever-shifting transition towards it, though he was still enough of a
mercantilist not to overlook the fact that it is in the transition that
we actually have our being: “It is only in this interval or
intermediate situation, between the acquisition of money and a rise of
prices, that the increasing quantity of gold and silver is favourable
to industry. ... It is of no manner of consequence, with regard to the
domestic happiness of a state, whether money be in a greater or less
quantity. The good policy of the magistrate consists only in keeping
it, if possible, still increasing; because by that means he keeps alive
a spirit of industry in the nation, and increases the state of labour
in which consists all real power and riches. A nation, whose money
decreases, is actually, at that time, weaker and more miserable than
another nation, which possesses no more money but is on the increasing
trend.” (Essay On Money, 1752).
[12].. It illustrates the completeness with which the mercantilist
view, that interest means interest on money (the view which is, as it
now seems to me, indubitably correct), has dropt out, that Prof.
Heckscher, as a good classical economist, sums up his account of
Locke's theory with the comment ― “Locke's argument would be
irrefutable ... if interest really were synonymous with the price for
the loan of money; as this is not so, it is entirely irrelevant” (op.
cit. vol. ii. p. 204).
[13]. Heckscher, op. cit. vol. ii. pp. 210, 21I.
[14]. Heckscher, op. cit. vol. ii. p. 228.
[15]. Heckscher, op. cit. vol. ii. p. 235.
[16]. Heckscher, op. cit. vol. ii. p. 122.
[17]. Heckscher, op. cit. vol. ii. P. 223.
[18]. Heckscher, op. cit. vol. ii. p. 178.
[19]. “Within the state, mercantilism pursued thoroughgoing dynamic
ends. But the important thing is that this was bound up with a static
conception of the total economic resources in the world; for this it
was that created that fundamental disharmony which sustained the
endless commercial wars.... This was the tragedy of mercantilism. Both
the Middle Ages with their universal static ideal and laissez-faire
with its universal dynamic ideal avoided this consequence” (Heckscher,
op. cit. vol. ii. pp. 25, 26).
[20]. The consistent appreciation of this truth by the International
Labour Office, first under Albert Thomas and subsequently under Mr. H.
B. Butler, has stood out conspicuously amongst the pronouncements of
the numerous post-war international bodies.
[21]. Heckscher, op. cit. vol. ii. pp. 176-7.
[22]. Op. cit. vol. ii. p. 335.
[23]. In his Letter to Adam Smith appended to his Defence of Usury.
[24]. Wealth of Nations, Book II, chap. 4.
[25]. Having started to quote Bentham in this context, I must remind
the reader of his finest passage: “The career of art, the great road
which receives the footsteps of projectors, may be considered as a
vast, and perhaps un-bounded, plain, bestrewed with gulphs, such as
Curtius was swallowed up in. Each requires a human victim to fall into
it ere it can close, but when it once closes, it closes to open no
more, and so much of the path is safe to those who follow.”
[26]. Born near the Luxembourg frontier of a German father and a French mother.
[27]. Gesell differed from George in recommending the payment of compensation when the land is nationalised.
[28]. The Natural Economic Order, pp. 297 et seq.
[29]. Heckscher, op. cit. vol. ii. p. 208.
[30]. Op. cit. vol. ii. p. 290.
[31]. Op. cit. vol. ii. p. 209.
[32]. Op. cit. vol. ii. p. 291.
[33]. In his History of English Thought in the Eighteenth Century
Stephen wrote (p. 297) in speaking of “the fallacy made celebrated by
Mandeville” that ..the complete confutation of it lies in the doctrine
― so rarely understood that its complete apprehension is, perhaps, the
best test of an economist ― that demand for commodities is not demand
for labour”.
[34]. Compare Adam Smith, the forerunner of the classical school, who
wrote, “What is prudence in the conduct of every private family can
scarce be folly in that of a great Kingdom” ― probably with reference
to the above passage from Mandeville.
[35]. Essays in Biography, pp. 139-47.
[36]. A letter from Malthus to Ricardo, dated July 7, 1821.
[37]. A letter from Malthus to Ricardo, dated July 16, 1822.
[38]. Preface to Malthus's Principles of Political Economy, pp. 8, 9.
[39]. Malthus's Principles of Political Economy, p. 363, footnote.
[40]. J. S. Mill, Political Economy, Book I. chapter v. Them is a most
important and penetrating discussion of this aspect of Mill's theory in
Mummery and Hobson's Physiology of Industry? pp. 38 et seq., and, in
particular, of his doctrine (which Marshall, in his very unsatisfactory
discussion of the Wages-Fund Theory, endeavoured to explain away) that
“a demand for commodities is not a demand for labour”.
[41]. “The Victorians and Investment”, Economic History, 1936.
[42]. Fullarton's tract On the Regulation of Currencies (1844) is the most interesting of his references.
[43]. J. M. Robertson's The Fallacy of Saving, published in 1892,
supported the heresy of Mummery and Hobson. But it is not a book of
much value or significance, being entirety lacking in the penetrating
intuitions of The Physiology of Industry.
[44]. In an address called “Confessions of an Economic Heretic”,
delivered before the London Ethical Society at Conway Hall on Sunday,
July 14, 1935. I reproduce it here by Mr. Hobson's permission.
[45]. Hobson had written disrespectfully in The Physiology of Industry,
p. 26: “Thrift is the source of national wealth, and the more thrifty a
nation is the more wealthy it becomes. Such is the common teaching of
almost all economists; many of them assume a tone of ethical dignity as
they plead the infinite value of thrift; this note alone in all their
dreary song has caught the favour of the public ear.”
[46]. Hobson and Mummery, Physiology of Industry, pp. iii-v.
[47]. Hobson and Mummery, Physiology of Industry, p. vi.
[48]. Op. cit. p. ix.
[49]. Op. cit. p. 27
[50]. Op. cit. pp. 50, 51
[51]. Op. cit. p. 69
[52]. Op. cit. p. 113
[53]. Op. cit. p. 100
[54]. Op. cit. p. 101
[55]. Op. cit. p. 79
[56]. Op. cit. p. 117.
[57]. Op. cit. P. 130.
[58]. Hobson and Mummery, Physiology of Industry, p. 131.
Chapter 24. Concluding Notes on the Social Philosophy towards which the General Theory might Lead
I
THE outstanding faults of the economic society in which we live are its
failure to provide for full employment and its arbitrary and
inequitable distribution of wealth and incomes. The bearing of the
foregoing theory on the first of these is obvious. But there are also
two important respects in which it is relevant to the second.
現代の経済社会の大きな欠点は完全雇用ができないこと、そして富と所得の偏在である。本書のこれまでの議論は明らかに完全雇用に関するものであるが、この理論は二つの重要な点で富の偏在にも関係している。
Since the end of the nineteenth century significant progress
towards the removal of very great disparities of wealth and income has
been achieved through the instrument of direct taxation ― income tax
and surtax（累進課税） and death duties（相続税） ― especially in Great Britain.
Many people would wish to see this process carried much further, but
they are deterred by two considerations; partly by the fear of making
skilful evasions（資本逃避、資金の国外流出） too much worth while and also of
diminishing unduly the motive towards
risk-taking（リスクの受け入れ、過度な課税は起業家の投資意欲を削ぐ）, but mainly, I think, by the
belief that the growth of capital depends upon the strength of the
motive towards individual saving and that for a large proportion of
this growth we are dependent on the savings of the rich out of their
superfluity.
19世紀末から富の偏在を直接税ー所得税、累進課税、相続税ーによって取り除くことが特に英国では行われてきたので、これをもっと推し進めるべきだという
考え方が強くなってる。しかし、これをやると資本逃避を助長したり投資意欲を削いでしまうのではないかという懸念がある。もう一つの懸念は、資本の成長は
貯蓄の個人的な動機の強さに依存し、その成長の大部分は金持ちがあり余る財産の中から回す貯蓄に依存するという考え方があって、そのために直接税の税率を
上げることには躊躇するのである。
Our argument does not affect the first of these considerations. But it
may considerably modify our attitude towards the second. For we have
seen that, up to the point where full employment prevails, the growth
of capital depends not at all on a low propensity to consume but is, on
the contrary, held back by it; and only in conditions of full
employment is a low propensity to consume conducive to the growth of
capital. Moreover, experience suggests that in existing conditions
saving by institutions and through sinking funds is more than adequate,
and that measures for the redistribution of incomes in a way likely to
raise the propensity to consume may prove positively favourable to the
growth of capital.
これまでの我々の議論は一つ目の懸念に答えるものではないが、これまでの議論によって２つ目の懸念に対する我々お対応は大きく変わってきた。というのは、
完全雇用に達するまでは、資本の成長は低い消費性向によって促進されるどころか、反対に阻止されることが分かったのである。そして、唯一完全雇用状況にお
いてのみ、低い消費性向が資本の成長に寄与するのである。さらに、現状においては、機関による貯蓄と減債基金は必要以上に充実しているし、消費を活発化さ
せるような所得の再分配化策が資本の成長を促すことは、経験的に分かっているのだ。
The existing confusion of the public mind on the matter is well
illustrated by the very common belief that the death duties are
responsible for a reduction in the capital wealth of the
country.<But> Assuming（仮定すれば） that the State applies the proceeds
of these duties to its ordinary outgoings so that taxes on incomes and
consumption are correspondingly reduced or avoided, it is, of course,
true that a fiscal policy of heavy death duties has the effect of
increasing the community's propensity to consume. But inasmuch as an
increase in the habitual propensity to consume will in general (i.e.
except in conditions of full employment) serve to increase at the same
time the inducement to invest, the inference commonly
drawn（一般に導かれる結論は真実とは正反対なのである） is the exact opposite of the truth.
この問題に関して一般世間の考え方が混乱していることは、相続税が一国の資本資産を減少させる原因だと一般に思われていることによく表れている。しかし、
仮に国が相続税収を一般財源にして所得税や消費課税をゼロにすれば、政策的に相続税を重くすれば消費性向を増加させる効果があることは当然確実である。一
方、一般的に（完全雇用状況を除けば）習慣的な消費性向が上昇すれば投資誘引は増加するのだから、一般に導かれている結論（＝相続税が資本を減少させる）
は間違っているのである。
Thus our argument leads towards the conclusion that in contemporary
conditions the growth of wealth, so far from being dependent on the
abstinence of the rich, as is commonly supposed, is more likely to be
impeded by it. One of the chief social justifications of great
inequality of wealth is, therefore, removed. I am not saying that there
are no other reasons, unaffected by our theory, capable of justifying
some measure of inequality in some circumstances. But it does dispose
of the most important of the reasons why hitherto we have thought it
prudent to move carefully（軽率な行動を取らない、浪費しない）. This particularly affects
our attitude towards death duties: for there are certain justifications
for inequality of incomes which do not apply equally to inequality of
inheritances.
一国の資本資産は人が金持ちになるための節約から生まれるのではない。それは逆に資本の成長を阻害する。だから、この面では、人が金持ちになるのはよいこ
とではない。別の面から見れば人が金持ちになることはよいこともあるだろう、しかし、浪費をしないことが賢明だと考える最大の理由はこれでなくなったので
ある。とくに金持ちの存在が経済に良くないとするこの考え方は、相続税に対する我々の態度に影響する。つまり、収入によって金持ちになる人があるのを正し
いとする理由があるとしても、相続によって人が金持ちになるのをよいとする理由はないのだ。
For my own part, I believe that there is social and psychological
justification for significant inequalities of incomes and wealth, but
not for such large disparities as exist today. There are valuable human
activities which require the motive of money-making and the environment
of private wealth-ownership for their full fruition. Moreover,
dangerous human proclivities can be canalised into comparatively
harmless channels by the existence of opportunities for money-making
and private wealth, which, if they cannot be satisfied in this way, may
find their outlet in cruelty, the reckless pursuit of personal power
and authority, and other forms of self-aggrandisement（増大）. It is better
that a man should tyrannise over his bank balance than over his
fellow-citizens; and whilst the former is sometimes denounced as being
but a means to the latter, sometimes at least it is an
alternative（選択肢、代替）.
私としては、社会の一部の人間だけが金持ちになることはそれほど心情的にも社会的にも悪いことだとは思わないが、現代のような大きな格差は良くないと思
う。価値ある事業の中には蓄財が必要なものもあるし、最後まで達成するためには個人的な資産の蓄積が欠かせない事業というものがある。さらには、人間の危
険な性癖が、比較的危険度の少ない蓄財という活動にはけ口を見出すということもある。その性癖は金儲けで満たされないと、残忍な行為や権力の獲得に走るこ
とがあるからである。誰かが仲間の国民の上に君臨して独裁者になるよりも銀行口座の上に君臨して大金持ちになる方がましだし、仮に大金持ちになることが独
裁者になるための手段として非難されることはあっても、少なくとも大金持ちになるだけで独裁者にはならないこともある。
But it is not necessary for the stimulation of these activities
and the satisfaction of these proclivities(性癖) that the game should be
played for such high stakes as at present. Much lower stakes will serve
the purpose equally well, as soon as the players are accustomed to
them. The task of transmuting human nature must not be confused with
the task of managing it. Though in the ideal commonwealth men may have
been taught or inspired or bred to take no interest in the stakes, it
may still be wise and prudent statesmanship to allow the game to be
played, subject to rules and limitations, so long as the average man,
or even a significant section of the community, is in fact strongly
addicted to the money-making passion.
しかしながら、単に蓄財を促すためやこのような人間の性癖を満たすために、この蓄財というゲームは今のような高い掛け率で行われる必要はない。この目的の
ためならもっと低い掛け率で充分である。プレーヤーはその掛け率に慣れればいいのである。人間の本姓を変えられないのなら人間の本姓を管理すればいいので
ある。理想国家では人は賭け事に興味が無いように教育することができるだろうが、ルールと規制のもとにゲームを許すのが賢明な政治である。普通の人間、そ
れも社会のかなり優秀な人間でも金儲け熱に取り付かれるものだからである。
II
There is, however, a second, much more fundamental inference from our
argument which has a bearing on the future of inequalities of wealth;
namely, our theory of the rate of interest.
富の偏在を税によって取り除くことは、我々の消費の理論から言えば、資本主義の発展を阻害するどころか助長するものであるというのが第一の結論だとすれ
ば、富の偏在の未来に関係する我々の理論、すなわち利子率に関する我々の理論からは第二のもっと根本的な結論を導き出すことが出来る。
The justification for a moderately high rate of interest has been found
hitherto in the necessity of providing a sufficient inducement to save.
But we have shown that the extent of effective saving is necessarily
determined by the scale of investment and that the scale of investment
is promoted by a low rate of interest, provided that we do not attempt
to stimulate it in this way beyond the point which corresponds to full
employment. Thus it is to our best advantage to reduce the rate of
interest to that point relatively to the schedule of the marginal
efficiency of capital at which there is full employment.
貯蓄を促進するには利子率はどちらと言えば高い方が良いとする考え方がある。ところが我々のこれまでの議論で見てきたように、適正な貯蓄の規模は必然的に
投資の規模によって決まるのであり、完全雇用を超えるまでは、投資は低い利子率によって促進されるのである。つまり、資本の限界効率のグラフが完全雇用に
対応する点までは、利子率は下げたほうがいいのである。
There can be no doubt that this criterion will lead to a much lower
rate of interest than has ruled hitherto; and, so far as one can guess
at the schedules of the marginal efficiency of capital corresponding to
increasing amounts of capital, the rate of interest is likely to fall
steadily, if it should be practicable to maintain conditions of more or
less continuous full employment unless, indeed, there is an excessive
change in the aggregate propensity to consume (including the State).
この考え方でいくと利子率はこれまで考えられてきたよりも大きく下がるのは疑いがない。だから、資本の規模が上昇過程にあると推測される場合には、利子率は確実に下がり続けるだろう。もちろん、それで消費性向が維持されて完全雇用の状態が維持できるのが条件である。
I feel sure that the demand for capital is strictly limited in
the sense that it would not be difficult to increase the stock of
capital up to a point where its marginal efficiency had fallen to a
very low figure. This would not mean that the use of capital
instruments would cost almost nothing, but only that the return from
them would have to cover little more than their exhaustion by wastage
and obsolescence together with some margin to cover risk and the
exercise of skill and judgment. In short, the aggregate return from
durable goods in the course of their life would, as in the case of
short-lived goods, just cover their labour costs of production plus an
allowance for risk and the costs of skill and supervision.
資本に対する需要（＝中古機械の購入）は限られてる。資本の限界効率（＝予想収益率）が非常に低い状態に至るまでは資本ストックが増加させるの（＝新品の
機械の購入）は困難ではないことだからである（新品の機械を買うのが簡単なので中古機械はなかなか売れない）。
Now, though this state of affairs would be quite compatible with some
measure of individualism, yet it would mean the euthanasia of the
rentier, and, consequently, the euthanasia of the cumulative oppressive
power of the capitalist to exploit the scarcity-value of capital.
Interest today rewards no genuine sacrifice, any more than does the
rent of land. The owner of capital can obtain interest because capital
is scarce, just as the owner of land can obtain rent because land is
scarce. But whilst there may be intrinsic reasons for the scarcity of
land, there are no intrinsic reasons for the scarcity of capital. An
intrinsic reason for such scarcity, in the sense of a genuine sacrifice
which could only be called forth by the offer of a reward in the shape
of interest, would not exist, in the long run, except in the event of
the individual propensity to consume proving to be of such a character
that net saving in conditions of full employment comes to an end before
capital has become sufficiently abundant. But even so, it will still be
possible for communal saving through the agency of the State to be
maintained at a level which will allow the growth of capital up to the
point where it ceases to be scarce.
I see, therefore, the rentier aspect of capitalism as a
transitional phase which will disappear when it has done its work. And
with the disappearance of its rentier aspect much else in it besides
will suffer a sea-change. It will be, moreover, a great advantage of
the order of events which I am advocating, that the euthanasia of the
rentier, of the functionless investor, will be nothing sudden, merely a
gradual but prolonged continuance of what we have seen recently in
Great Britain, and will need no revolution.
Thus we might aim in practice (there being nothing in this which is
unattainable) at an increase in the volume of capital until it ceases
to be scarce, so that the functionless investor will no longer receive
a bonus; and at a scheme of direct taxation which allows the
intelligence and determination and executive skill of the financier,
the entrepreneur et hoc genus omne (who are certainly so fond of their
craft that their labour could be obtained much cheaper than at
present), to be harnessed to the service of the community on reasonable
terms of reward.
At the same time we must recognise that only experience can show how
far the common will, embodied in the policy of the State, ought to be
directed to increasing and supplementing the inducement to invest; and
how far it is safe to stimulate the average propensity to consume,
without foregoing our aim of depriving capital of its scarcity-value
within one or two generations. It may turn out that the propensity to
consume will be so easily strengthened by the effects of a falling rate
of interest, that full employment can be reached with a rate of
accumulation little greater than at present. In this event a scheme for
the higher taxation of large incomes and inheritances might be open to
the objection that it would lead to full employment with a rate of
accumulation which was reduced considerably below the current level. I
must not be supposed to deny the possibility, or even the probability,
of this outcome. For in such matters it is rash to predict how the
average man will react to a changed environment. If, however, it should
prove easy to secure an approximation to full employment with a rate of
accumulation not much greater than at present, an outstanding problem
will at least have been solved. And it would remain for separate
decision on what scale and by what means it is right and reasonable to
call on the living generation to restrict their consumption, so as to
establish in course of time, a state of full investment for their
successors.
III
In some other respects the foregoing theory is moderately
conservative in its implications. For whilst it indicates the vital
importance of establishing certain central controls in matters which
are now left in the main to individual initiative, there are wide
fields of activity which are unaffected. The State will have to
exercise a guiding influence on the propensity to consume partly
through its scheme of taxation, partly by fixing the rate of interest,
and partly, perhaps, in other ways. Furthermore, it seems unlikely that
the influence of banking policy on the rate of interest will be
sufficient by itself to determine an optimum rate of investment. I
conceive, therefore, that a somewhat comprehensive socialisation of
investment will prove the only means of securing an approximation to
full employment; though this need not exclude all manner of compromises
and of devices by which public authority will co-operate with private
initiative. But beyond this no obvious case is made out for a system of
State Socialism which would embrace most of the economic life of the
community. It is not the ownership of the instruments of production
which it is important for the State to assume. If the State is able to
determine the aggregate amount of resources devoted to augmenting the
instruments and the basic rate of reward to those who own them, it will
have accomplished all that is necessary. Moreover, the necessary
measures of socialisation can be introduced gradually and without a
break in the general traditions of society.
Our criticism of the accepted classical theory of economics has
consisted not so much in finding logical flaws in its analysis as in
pointing out that its tacit assumptions are seldom or never satisfied,
with the result that it cannot solve the economic problems of the
actual world. But if our central controls succeed in establishing an
aggregate volume of output corresponding to full employment as nearly
as is practicable, the classical theory comes into its own again from
this point onwards. If we suppose the volume of output to be given,
i.e. to be determined by forces outside the classical scheme of
thought, then there is no objection to be raised against the classical
analysis of the manner in which private self-interest will determine
what in particular is produced, in what proportions the factors of
production will be combined to produce it, and how the value of the
final product will be distributed between them. Again, if we have dealt
otherwise with the problem of thrift, there is no objection to be
raised against the modern classical theory as to the degree of
consilience between private and public advantage in conditions of
perfect and imperfect competition respectively. Thus, apart from the
necessity of central controls to bring about an adjustment between the
propensity to consume and the inducement to invest, there is no more
reason to socialise economic life than there was before.
To put the point concretely, I see no reason to suppose that the
existing system seriously misemploys the factors of production which
are in use. There are, of course, errors of foresight; but these would
not be avoided by centralising decisions. When 9,000,000 men are
employed out of 10,000,000 willing and able to work, there is no
evidence that the labour of these 9,000,000 men is misdirected. The
complaint against the present system is not that these 9,000,000 men
ought to be employed on different tasks, but that tasks should be
available for the remaining 1,000,000 men. It is in determining the
volume, not the direction, of actual employment that the existing
system has broken down.
Thus I agree with Gesell that the result of filling in the gaps in the
classical theory is not to dispose of the 'Manchester System', but to
indicate the nature of the environment which the free play of economic
forces requires if it is to realise the full potentialities of
production. The central controls necessary to ensure full employment
will, of course, involve a large extension of the traditional functions
of government. Furthermore, the modern classical theory has itself
called attention to various conditions in which the free play of
economic forces may need to be curbed or guided. But there will still
remain a wide field for the exercise of private initiative and
responsibility. Within this field the traditional advantages of
individualism will still hold good.
Let us stop for a moment to remind ourselves what these advantages are.
They are partly advantages of efficiency ― the advantages of
decentralisation and of the play of self-interest. The advantage to
efficiency of the decentralisation of decisions and of individual
responsibility is even greater, perhaps, than the nineteenth century
supposed; and the reaction against the appeal to self-interest may have
gone too far. But, above all, individualism, if it can be purged of its
defects and its abuses, is the best safeguard of personal liberty in
the sense that, compared with any other system, it greatly widens the
field for the exercise of personal choice. It is also the best
safeguard of the variety of life, which emerges precisely from this
extended field of personal choice, and the loss of which is the
greatest of all the losses of the homogeneous or totalitarian state.
For this variety preserves the traditions which embody the most secure
and successful choices of former generations; it colours the present
with the diversification of its fancy; and, being the handmaid of
experiment as well as of tradition and of fancy, it is the most
powerful instrument to better the future.
Whilst, therefore, the enlargement of the functions of government,
involved in the task of adjusting to one another the propensity to
consume and the inducement to invest, would seem to a
nineteenth-century publicist or to a contemporary American financier to
be a terrific encroachment on individualism. I defend it, on the
contrary, both as the only practicable means of avoiding the
destruction of existing economic forms in their entirety and as the
condition of the successful functioning of individual initiative.
For if effective demand is deficient, not only is the public scandal of
wasted resources intolerable, but the individual enterpriser who seeks
to bring these resources into action is operating with the odds loaded
against him. The game of hazard which he plays is furnished with many
zeros, so that the players as a whole will lose if they have the energy
and hope to deal all the cards. Hitherto the increment of the world's
wealth has fallen short of the aggregate of positive individual
savings; and the difference has been made up by the losses of those
whose courage and initiative have not been supplemented by exceptional
skill or unusual good fortune. But if effective demand is adequate,
average skill and average good fortune will be enough.
The authoritarian state systems of today seem to solve the problem of
unemployment at the expense of efficiency and of freedom. It is certain
that the world will not much longer tolerate the unemployment which,
apart from brief intervals of excitement, is associated and in my
opinion, inevitably associated with present-day capitalistic
individualism. But it may be possible by a right analysis of the
problem to cure the disease whilst preserving efficiency and freedom.
IV
I have mentioned in passing that the new system might be more
favourable to peace than the old has been. It is worth while to repeat
and emphasise that aspect.
War has several causes. Dictators and others such, to whom war offers,
in expectation at least, a pleasurable excitement, find it easy to work
on the natural bellicosity of their peoples. But, over and above this,
facilitating their task of fanning the popular flame, are the economic
causes of war, namely, the pressure of population and the competitive
struggle for markets. It is the second factor, which probably played a
predominant part in the nineteenth century, and might again, that is
germane to this discussion.
I have pointed out in the preceding chapter that, under the
system of domestic laissez-faire and an international gold standard
such as was orthodox in the latter half of the nineteenth century,
there was no means open to a government whereby to mitigate economic
distress at home except through the competitive struggle for markets.
For all measures helpful to a state of chronic or intermittent
under-employment were ruled out, except measures to improve the balance
of trade on income account.
Thus, whilst economists were accustomed to applaud the prevailing
international system as furnishing the fruits of the international
division of labour and harmonising at the same time the interests of
different nations, there lay concealed a less benign influence; and
those statesmen were moved by common sense and a correct apprehension
of the true course of events, who believed that if a rich, old country
were to neglect the struggle for markets its prosperity would droop and
fail. But if nations can learn to provide themselves with full
employment by their domestic policy (and, we must add, if they can also
attain equilibrium in the trend of their population), there need be no
important economic forces calculated to set the interest of one country
against that of its neighbours. There would still be room for the
international division of labour and for international lending in
appropriate conditions. But there would no longer be a pressing motive
why one country need force its wares on another or repulse the
offerings of its neighbour, not because this was necessary to enable it
to pay for what it wished to purchase, but with the express object of
upsetting the equilibrium of payments so as to develop a balance of
trade in its own favour. International trade would cease to be what it
is, namely, a desperate expedient to maintain employment at home by
forcing sales on foreign markets and restricting purchases, which, if
successful, will merely shift the problem of unemployment to the
neighbour which is worsted in the struggle, but a willing and unimpeded
exchange of goods and services in conditions of mutual advantage.
V
Is the fulfilment of these ideas a visionary hope? Have they
insufficient roots in the motives which govern the evolution of
political society? Are the interests which they will thwart stronger
and more obvious than those which they will serve?
このような考え方の実現は単なる夢物語だろうか。それは政治の世界の発展を左右する動機の中には不充分は根しか持っていないだろうか。このような考えがもたらす利益は、それが打ち壊す利益よりも大きなものではないだろうか。
I do not attempt an answer in this place. It would need a volume
of a different character from this one to indicate even in outline the
practical measures in which they might be gradually clothed. But if the
ideas are correct ― an hypothesis on which the author himself must
necessarily base what he writes ― it would be a mistake, I predict, to
dispute their potency over a period of time. At the present moment
people are unusually expectant of a more fundamental diagnosis; more
particularly ready to receive it; eager to try it out, if it should be
even plausible. But apart from this contemporary mood, the ideas of
economists and political philosophers, both when they are right and
when they are wrong, are more powerful than is commonly understood.
Indeed the world is ruled by little else.
ここで私はその答えを出そうとは思わない。この考え方を実現するための実際的な方法の概略を示すだけでもこの本とは性格をことにした書物が必要だろう。し
かしながら、あらかじめ言っておくが、もしこの考え方が正しければ、― 物書きは自分の書いたものが必ずや正しいと仮定している―その実現可能性を長時間
かけて議論していると失敗するだろう。現時点で人々はもっと根本的な診断を異常なほどに待ち望んでいるし、それがもっともらしくありさせすれば、今すぐに
でも受け入れて、試そうとしているからである。そもそも、この現代の雰囲気は別としても、経済学者と政治哲学者たちの考え方すなわち思想は、それが正しく
ても間違っていても、普通考えられている以上に強力である。実際、世界を支配しているのは他ならぬ思想なのだ。
Practical men, who believe themselves to be quite exempt from
any intellectual influences, are usually the slaves of some defunct
economist. Madmen in authority, who hear voices in the air, are
distilling their frenzy from some academic scribbler of a few years
back. I am sure that the power of vested interests is vastly
exaggerated compared with the gradual encroachment of ideas. Not,
indeed, immediately, but after a certain interval; for in the field of
economic and political philosophy there are not many who are influenced
by new theories after they are twenty-five or thirty years of age, so
that the ideas which civil servants and politicians and even agitators
apply to current events are not likely to be the newest. But, soon or
late, it is ideas, not vested interests, which are dangerous for good
or evil.
Translated into Japanese by （c） Tomokazu Hanafusa 2010.6.13-2012.9.15