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Jevons, William Stanley

Jevons, William Stanley

WORKS BY JEVONS

SUPPLEMENTARY BIBLIOGRAPHY

William Stanley Jevons (1835–1882), one of the greatest and most original of English economists, was born in Liverpool. His father was an iron merchant and engineer who constructed one of the first iron boats and also wrote on economics and legal subjects; his mother was a daughter of the historian William Roscoe. Both parents were Unitarians. At the age of 15 Jevons was sent as a boarder to University College School, London, and a year later he entered University College. Although he studied chemistry and botany there, it was during these London years that his interests, always wide-ranging, first turned to the study of society. “It was in 1851,” he later wrote, “that I first began, at the age of sixteen, to study the industrial mechanism of society” (1905, p. vii). He used to go for long walks through the poorest parts of Dickensian London, observing the condition of the people—as Alfred Marshall was later to do in the great industrial cities. At 17 he wrote of “wanting very much to get Mayhew’s London Labour & London Poor,as that is the only book I know of to learn a little about the real condition of the poor in London” (1886, p. 29). Already he was imbued with a sense of mission: “I began to think that I could and ought to do more than others. A vague desire and determination grew upon me” (1886, pp. 12–13). He later described this as a determination “to be powerfully good, that is to be good, not towards one, or a dozen, or a hundred, but towards a nation or the world” (1886, p. 96).

In 1853, when still under 19, Jevons was offered a very responsible and well-paid post as assayer at the newly established mint at Sydney, Australia. The collapse of the family firm in the 1847–1848 crisis had left his family in straitened circumstances, and he reluctantly, through a sense of duty, accepted the offer. The combination of leisure and solitude during his five years in Sydney provided, for one as powerfully inner-directed as Jevons, ideal conditions for the development of his great intellectual originality and capacity for independent thought. Meteorology became a main interest, and a paper on the climate of Australia was one of his first publications (1859). He also continued his early interests in urban problems and in conducting social surveys; he planned a work entitled “Notes and Researches on Social Statistics or the Science of Towns.” He completed some sections on Sydney, but he did not publish anything, nor did he ever return to his “science of towns.”

In 1857 political economy began to become his main interest. As an economist, Jevons was entirely self-taught and the originality of his thought is apparent from his first work. He had no reverence for the prevailing classical orthodoxies and from the beginning saw economic problems in what was to be the characteristically neoclassical manner, that is, as problems of valuation and optimal allocation. In a letter of February 1858 he wrote to his sister:

I am glad you find political economy tolerable. The Wealth of Nations is perhaps one of the driest on the subject. You will perceive that economy, scientifically speaking, is a very contracted science; it is in fact a sort of vague mathematics which calculates the causes and effects of man’s industry, and shows how it may best be applied. … I have an idea, which I do not object to mention to you, that my insight into the foundations and nature of the knowledge of man is deeper than that of most men or writers. In fact, I think that it is my mission to apply myself to such subjects, and it is my intention to do so. … Thoroughly to understand the principles of society appears to me now the most cogent business. (1886, p. 101)

Jevons’ first articles were concerned with railway and land problems in New South Wales (1857a; 1857b). One of the books he read in 1857 was Dionysius Lardner’s Railway Economy. Lardner knew Cournot’s work, and his analysis of the profit-maximizing rates for railways had close similarities with Cournot’s treatment of monopoly. Some elements of Cournot’s pioneering marginal analysis presumably filtered through to Jevons. However, Jevons was not to be concerned with the theory of the firm, the great achievement of Cournot, but with utility and the consumer. In fact, though Jevons doubtless owed a little to Bentham and to one or two other lesser-known English utility theorists, such as Richard Jennings, there can be no doubt as to the high and substantial degree of independent originality in his marginal utility theory.

Jevons’ academic career . Jevons returned to England in 1859 and resumed his studies at University College for his B.A. and M.A. degrees. He came back from Australia not only with the means to carry on his studies but also with a stock of ideas, which he was to develop in his next few years of remarkable pioneering achievement in London and Manchester.

In October 1863 he took up a post as tutor at Owens College, Manchester (later, the University of Manchester), and was thus launched on an academic career, being appointed in 1866 as professor of logic and mental and moral philosophy and of political economy. The range of his official titles was no wider than his interests and contributions to knowledge. He married a daughter of the founder of the Manchester Guardian in 1867 and stayed in Manchester until 1876, when he moved to University College, London. He always found lecturing a great strain and resigned his chair in 1880.

Writings, 1859–1871 . Jevons’ work between the time he returned to England and the publication of his fully developed theory of value, The Theory of Political Economy (1871), can be roughly divided into three categories: the first formulation of his theory of value, a group of papers on monetary statistics, and a full-length book on public policy, The Coal Question (1865).

In 1860 he wrote his brother that “in the last few months I have fortunately struck out what I have no doubt is the true Theory of Economy, so thorough-going and consistent, that I cannot now read other books on the subject without indignation. … One of the most important axioms is, that as the quantity of any commodity, for instance, plain food, which a man has to consume, increases, so the utility or benefit derived from the last portion used decreases in degree” (1886, p. 151). Jevons wrote up his theory of value in a paper to the British Association for the Advancement of Science in 1862; it was entitled “Notice of a General Mathematical Theory of Political Economy” and was first printed four years later. Little or no recognition was given to this first statement of Jevons’ theory of value—and, indeed, his later, much fuller, statement in The Theory of Political Economy (1871) was at first also neglected.

Jevons’ early and finest papers in monetary statistics were published in this period: “On the Study of Periodic Commercial Fluctuations” (1884), also submitted to the British Association in 1862, which included a pioneering analysis of seasonal variations; and perhaps the greatest of all his works, “A Serious Fall in the Value of Gold Ascertained, and Its Social Effects Set Forth” (1863). In the decade or so following the mid-century gold discoveries in California and Australia, there had been much controversy regarding their effects on the level of prices. Some economists, John Ramsey McCulloch and William Newmarch, for example, held that no significant rise in the general level of prices had taken place. Jevons, in his 1863 pamphlet, provided a precise estimate of the fall in the value of gold, that is, 9 per cent between 1848 and 1860, which was later shown to have been remarkably accurate. In so doing he made one of the greatest single contributions to the technique of constructing price index numbers [seeIndex Numbers]. Indeed, according to Keynes, on the subject of index numbers Jevons “made as much progress in this brief pamphlet as has been made by all succeeding authors put together” (Keynes [1933] 1951, p. 269). Jevons also touched, in this work, on the subject of economic crises, which he then seemed inclined to explain in terms of periodically excessive and disproportional investment—along similar lines as James Wilson. But when he returned to the problem in subsequent essays, he developed his theory that periodic sunspots cause bad harvests and hence economic depressions. His statistical evidence for this theory was never very convincing, but the theory may have had more plausibility for explaining Britain’s depressions in the middle decades of the nineteenth century than it would seem to have had for subsequent periods.

Jevons’ mainly statistical papers in the fields of money, prices, and fluctuations were collected posthumously in Investigations in Currency and Finance. They indicate that he was a pioneer in the graphic presentation of economic and financial statistics, adapting for the charting of the economic “weather” the methods used in his meteorological studies. Like Marshall and Pareto, Jevons was one of the few leading late nineteenth-century neoclassical exponents of deductive marginal analysis who also made valuable contributions to statistical and descriptive economics, in “an attempt”—as he put it in some notes for an introduction to theInvestigations —“to substitute exact inquiries, exact numerical calculations, for guess-work and groundless argument” ([1863–1884] 1964, p. xxiv).

The Coal Question (1865), Jevons’ first full-length book, brought him a wider measure of fame and certainly succeeded in its aim of rousing public opinion. In it he warned his countrymen that British coal deposits were exhaustible and that the cost of coal would rise as the best and easiest seams were used up. Jevons did not foresee the development of other major sources of power—just as Malthus had not foreseen the development of great overseas supplies of food. But the book certainly shows prophetic insight into the inevitably temporary nature of Britain’s coal-based industrial leadership, then at its peak. He also foresaw the rising industrial power of the United States. The work is a masterly tract in applied economics and an achievement in a quite different genre from his contributions to economic theory and monetary statistics.

Jevons’ theory of political economy . Jevons had conceived the essentials of his theory of value by 1860 and had written them up briefly in his 1862 paper to the British Association; little notice, however, was taken. For some years he turned to a wide range of other subjects and from 1866 to 1870 was absorbed in problems of logic and scientific method.

The publication in 1870 of Fleeming Jenkin’s “The Graphic Representation of the Laws of Supply and Demand,” and subsequent correspondence with Jenkin, seems to have stimulated Jevons to publish more fully his ideas on the theory of value and so to establish his priority with regard to the new approach. The Theory of Political Economy was rapidly written (though not perhaps as rapidly as John Stuart Mill’s Principles) and published in October 1871. Although it was not fully appreciated when it was first published, this book opened a new epoch in the history of economic thought, and it is the work for which Jevons is best known. Though it has many brilliantly original and challenging passages, its argument is imperfectly or incompletely developed at various important points. Much was left to be worked out in subsequent decades, and even the central concept of utility was soon to be fundamentally called in question. Nevertheless, Jevons did in fact provide a new point of departure for economic analysis.

Jevons’ theory of utility and value was subjectively highly original. Compared with the other two pioneers of the marginal utility theory in the early 1870s, Carl Menger and Léon Walras, Jevons had much less to build on. Menger knew the works of Friedrich Hermann, Albert Schäffie, and Hans Mangoldt, and Walras had behind him the whole French tradition of utility and scarcity theory. When Jevons came in 1879 to write the preface to the second edition of his Theory, he too had become acquainted with this literature and gave a masterly survey—itself a pioneer achievement in economic scholarship—of the contributions to marginal analysis and utility theory by his predecessors and contemporaries. Of course, neither the marginal concept nor the analysis of the relation of utility to value was absolutely novel in 1871. It was simply that the coincidence in the early 1870s of Jevons, Menger, and Walras, each almost simultaneously publishing his version of the theory, could, in due course, be seen as the opening of a new period in economic theorizing. As Walras wrote to Cournot in 1874: “M. Jevons et moi avons amené la question à un point tel, qu’elle ne pourra bientôt plus ätre écartée par les économistes” (“Jevons and I have brought the matter to the point where economists will soon be unable to ignore it”; Walras & Cournot 1873–1875).

The Theory of Political Economy begins on a note of revolutionary challenge to classical orthodoxy, and particularly to John Stuart Mill’s Principles. Jevons expressed complete confidence in the substantial correctness of his proposition that “value depends entirely on utility.” At the same time, he made enthusiastic claims for mathematical methods that were then highly controversial. He started on markedly Benthamite lines with the theory of pleasure and pain, then proceeded to the theory of utility. For Jevons, as for Menger, Walras, and Marshall, but not for Edgeworth, the utility function for a commodity is related to the quantity of that commodity only. He formulated the law of diminishing utility and then proceeded to deduce the utility-maximizing allocation formula for the consumer, establishing the pattern for much of the subsequent neoclassical theorizing. Jevons did not use the concept of marginal utility but rather that of “the final degree of utility,” or marginal utility (that is, the utility of the marginal increment) divided by the size of the marginal increment. In his words: “The keystone of the whole Theory of Exchange, and of the principal problems of Economics, lies in this proposition—The ratio of exchange of any two commodities will be the reciprocal of the ratio of the final degrees of utility of the quantities of commodity available for consumption after the exchange is completed” ([1871] 1957, p. 95).

Jevons’ analysis of market exchanges, however, is highly unsatisfactory. He attempted to generalize the analysis of two-party, two-commodity barter to apply to a competitive market. Although he contributed to the development of a precise definition of competitive conditions through his “law of indifference,” his use of the concept of trading bodies, with their collective marginal utilities, was mistaken.

Jevons concluded his chapter on exchange with an eloquent attack on labor and cost-of-production theories of value:

The fact is, that labour once spent has no influence on the future value of any article: it is gone and lost for ever. In commerce bygones are for ever bygones; and we are always starting clear at each moment, judging the values of things with a view to future utility. Industry is essentially prospective, not retrospective; and seldom does the result of any undertaking exactly coincide with the first intentions of its promoters, (ibid., p. 164)

He then provided his own summary of the determination of values:

But though labour is never the cause of value, it is in a large proportion of cases the determining circumstance, and in the following way: Value depends solely on the final degree of utility. How can we vary this degree of utility×By having more or less of the commodity to consume. And how shall we get more or less of it×By spending more or less labour in obtaining a supply. According to this view, then, there are two steps between labour and value. Labour affects supply, and supply affects the degree of utility, which governs value, or the ratio of exchange. In order that there may be no possible mistake about this all-important series of relations, I will re-state it in a tabular form, as follows:

Cost of production determines supply;
Supply determines final degree of utility;
Final degree of utility determines value
. (ibid., p. 165)

This typically and brilliantly incisive summary led Keynes to comment that Jevons chiseled in stone while Marshall knitted in wool. Nevertheless, two criticisms of Jevons’ conclusion—both actually first suggested by Marshall—can be made. The first is that it does not seem consistent with Jevons’ basic proposition that value depends solely on final degree of utility; in fact, as traced back by Jevons, it is the classical cost of production that is the first determinant. Second, the determinants of value have, in any case, to be sought not in one-way causal chains but in mutual determination and interdependence.

Jevons’ Theory of Political Economy provides a sketch of only one half of the field of microeconomic analysis—the theory of the consumer. Jevorfs attempted no theory of the firm. But his theories of labor and capital are both significant. That of labor supply states an allocation principle according to which the marginal disutility of labor, which after a point increases, is balanced against the diminishing marginal utility of the product. The free laborer “will cease to labour just at the point when the pain becomes equal to the corresponding pleasure gained. … In this, as in the other questions of Economics, all depends upon the final increments, and we have expressed in the above formula the final equivalence of labour and utility” (ibid., pp. 176–177). The concept of “the free laborer” involves the often unrealistic assumption that the individual can continuously adjust his supply of labor and does not have to supply it in large, indivisible units.

Jevons’ theory of capital or “capitalization” anticipates in important respects the theory expounded so voluminously in 1889 by Böhm-Bawerk [seeBÖhm-Bawerk]. Jevons stated that capital has two dimensions, the quantity and the period of time for which it is invested, and that, in Böhm-Bawerk’s terminology, an increase in capital amounts to “a lengthening of the period of production”: “Whatever improvements in the supply of commodities lengthen the average interval between the moment when labour is exerted and its ultimate result or purpose accomplished, such improvements depend upon the use of capital” ([1871] 1957, pp. 228–229). It is in his theory of capital that Jevons came nearest to stating a marginal productivity theory: “The rate of interest depends on the advantage of the last increment of capital, and the advantages of previous increments may be greater in almost any ratio” (ibid., p. 256).

In the preface to the second edition Jevons hinted at a marginal productivity theory by remarking that distribution is entirely subject to the principles of value. Except in his theory of capital and interest, however, he did not work out this idea.

Jevons’ ideas met with little acceptance in his lifetime. Cairnes, Marshall, and Sidgwick were all in various ways coolly skeptical. Simon Newcomb in the United States was one of the few to give them some recognition, although he justifiably felt that Jevons’ Theory was not as outstanding an achievement as Cournot’s Recherches. Nor was Jevons the founder of a school of disciples, as were Menger and Marshall, although P. H. Wicksteed later emerged as an enthusiastic propagator of what he regarded as Jevons’ theoretical revolution.

Nevertheless, from 1871, as we can now see, a new pattern had been set for economic theorizing. Exchange and allocation became the central problem in a much more exclusive way than previously. Economic analysis was built up logically on the foundation of the maximizing individual. This permitted much more precision and a great development of mathematical formulation; but it made also for greater abstraction and a narrowing of focus, compared with classical political economy.

Economic and social reform.

In his Lecture Notes on Types of Economic Theory (1949), Wesley C. Mitchell described Jevons as primarily an economic “scientist,” more interested in developing detachedly the methods and criteria of the natural sciences in the social and economic field than in immediate practical reforms. It is true that his great contributions both to statistical and analytical economics have this scientific emphasis. But in his youth he certainly showed a deeply “engaged” reforming approach to social problems, and he continued throughout his tragically abbreviated career to contribute to the discussion of the practical problems of social reform. He concerned himself especially with questions of state control and management, supporting the nationalization of telegraphs but opposing that of the railways.

Considering his temperament, upbringing, and family and social background, it is not surprising that Jevons was a sturdy individualist. Indeed, the opening words of his first article on political economy (published in Australia in 1857), were: “Freedom for all commercial transactions is the spirit of improved legislation.” In his inaugural lecture at Manchester (1866) he warned that the greatest danger was that the “working classes, with their growing numbers and powers of combination, may be led by ignorance to arrest the true growth of our liberty, political and commercial.” A trade union, he held, could benefit its members only at the expense of their fellow workers outside the union and of consumers generally. Jevons was critical also of both public and private charity, and of the incipient social services, as weakening the initiative and self-reliance of the people. In his presidential address to the British Association for the Advancement of Science in 1870, he welcomed the great Education Act of that year, which established elementary education in Britain, but he complained that pauperism was “almost as prevalent as ever,” holding that that was “precisely what Malthus would have predicted of a population which, while supplied with easily earned wealth, … [is] bribed by the mistaken benevolence of the richer classes into a neglect of the future” ([1870] 1962, p. 27). He argued that although, according to his calculations, the tax burden then was spread roughly in proportion to incomes, those poorer families who consumed only “moderate quantities of tobacco and spirituous liquor” were not contributing proportionally or sufficiently. He therefore recommended that it would be “inexpedient to proceed further in the reduction of the customs and excise duties” ([1870] 1962, p. 34).

It seems that Jevons may have somewhat modified these rigorous views in his later years. At any rate, like Cairnes and Sidgwick, he rejected the laissez-faire maxim, then widely regarded as the orthodox lesson of political economy, and he called for a systematic analysis of economic policy:

While population grows more numerous and dense, while industry becomes more complex and interdependent, as we travel faster and make use of more intense forces, we shall necessarily need more legislative supervision. If such a thing is possible, we need a new branch of political and statistical science which shall carefully investigate the limits to the laissez-faire principle, and show where we want greater freedom and where less. … Instead of one dictum, laissez-faire, laissez-passer, we must have at least one science, one new branch of the old political economy. ([1876] 1905, pp. 203–206)

Jevons’ main contribution to economic policy lies in The State in Relation to Labour (1882), published in the year of his death. Here he reasserted his proposition that trade unions can improve the position of their members only at the expense of the rest of the community. But he recognized that “one result which clearly emerges from a calm review is that all classes of society are trades-unionists at heart, and differ chiefly in the boldness, ability and secrecy with which they push their respective interests” (1882, p. vi). He placed his hopes for the future, perhaps rather optimistically, in industrial partnership, which would bind the interests of the employer and workman more closely together. In The State in Relation to Labour, Jevons developed a much more cautious, empirical, and antidogmatic approach to the principles of policy than was suggested by some of his earlier attitudes. In fact, in his conclusion to that work he gives us one of the finest and most eloquent statements of English empiricism:

It is clear that there can be no royal road to legislation in such matters. We cannot expect to agree in utilitarian estimates, at least without much debate. We must agree to differ, and though we are bound to argue fearlessly, it should be with the consciousness that there is room for wide and bona fide difference of opinion. We must consent to advance cautiously, step by step, feeling our way, adopting no foregone conclusions, trusting no single science, expecting no infallible guide. We must neither maximise the functions of government at the beck of quasi-military officials, nor minimise them according to the theories of the very best philosophers. We must learn to judge each case upon its merits, interpreting with painful care all experience which can be brought to bear upon the matter. (1882, p. 166)

Logic and the principles of science . The wide range not only of Jevons’ interests but of his important contributions to knowledge is as remarkable as his path-breaking, fundamental originality of thought. He wrote almost as much on logic and scientific method as on political economy, in both fields publishing valuable, widely read textbooks as well as major original works. The Principles of Science (1874) has been recognized as a pioneer work, in important respects well ahead of its time. Especially notable was his development of the fundamentals of formal logic on the lines of George Boole, and his construction of a machine, still extant (a “logical piano,” as Ernest Nagel called it) for the mechanical solution of deductive problems—an anticipation of modern computing machines (see Jevons [1874] 1958, p. xlix). Jevons also developed the hypothetico-deductive approach, expounded more recently by Karl Popper, in that he rejected the Baconian conception of scientific enquiry as starting from the accumulation of facts and stressed the role of conjectures and hypotheses. “Inductive investigation,” he wrote, “consists in the union of hypothesis and experiment” (ibid., p. 525).

Jevons was drowned in a swimming accident at an age (46) when many great thinkers—for example, Marshall—had not completed a fraction of the work for which they were subsequently renowned. Among the books he left unfinished are a treatise on religion and science, in which he stressed their complete compatibility, an edition of The Wealth of Nations, to be prefaced by a survey of the history of economic thought, and an examination of Mill’s philosophy. But the greatest loss, certainly for economists, was the unfinished Principles of Economics, some fragments of which were subsequently published under the editorship of Henry Higgs (1905). In this comprehensive work he would almost certainly have worked out further the marginal analysis of which he had been the pioneer, combining it with his essential contributions to the explanation of commercial fluctuations and with a treatment of that new branch of the subject, which he had called for, dealing with the principles of economic policy. Keynes, on first meeting Jevons’ work at the age of 22, wrote: “I am convinced that he was one of the minds of the century. He has the curiously exciting style of writing which one gets if one is good enough” (Harrod 1951, pp. 106–107). This is no overstatement of the case. For breadth, variety, originality, and incisive penetration, Jevons’ work as economist, statistician, logician, and philosopher is among the greatest of modern times.

T. W. Hutchison

[See alsoUtility; andthe biographies of Mangoldt; Marshall; Menger; Mill, article oneconomic contributions; Newcomb; Walras; Wlcksteed.]

WORKS BY JEVONS

1857a The Public Lands of New South Wales. Empire (Sydney) June 23.

1857b Comparison of the Land and Railway Policy of New South Wales. Empire (Sydney) April 7.

1859 Climates of Australia and New Zealand. Waugh’s Australian Almanack (Sydney) [1859]: 1–52.

1862 Notice of a General Mathematical Theory of Political Economy. British Association for the Advancement of Science, Reports 32:158–159.

(1863) 1964 A Serious Fall in the Value of Gold Ascertained, and Its Social Effects Set Forth. Pages 13–111 in W. Stanley Jevons, Investigations in Currency and Finance. New York: Kelley.

(1863–1884) 1964 Investigations in Currency and Finance. With a preface by Stanley H. Jevons. New York: Kelley. → Published posthumously.

(1865) 1906 The Coal Question: An Inquiry Concerning the Progress of the Nation, and the Probable Exhaustion of Our Coal-mines. 3d ed., rev. Edited by A. W. Flux. London and New York: Macmillan.

1866 An Introductory Lecture on the Importance of Diffusing a Knowledge of Political Economy. Manchester (England): No publisher given.

(1870) 1962 Economic Policy. Pages 25–40 in British Association for the Advancement of Science, Economic Science and Statistics Section, Essays in Economic Method: Selected Papers … 1860–1913. London: Duckworth. → First published as “Address to the Section of Economic Science and Statistics” in Volume 40 of the Association’s Reports.

(1871) 1957 The Theory of Political Economy. 5th ed. New York: Kelley. → Pages xi-lii contain the preface to the second edition. A list of Jevons’ economic writings appears on pages 315–321.

(1874) 1958 The Principles of Science: A Treatise on Logic and Scientific Method. With a new introduction by Ernest Nagel. New York: Dover.

(1876) 1905 The Future of Political Economy. Pages 185–206 in W. Stanley Jevons, The Principles of Economics: A Fragment of a Treatise on the Industrial Mechanism of Society and Other Papers. London and New York: Macmillan.

(1882) 1910 The State in Relation to Labour. 4th ed. With an introduction by Francis W. Hirst. London: Macmillan.

(1884) 1964 On the Study of Periodic Commercial Fluctuations. Pages 1–11 in W. Stanley Jevons, Investigations in Currency and Finance. New York: Kelley.

1886 Letters & Journal of W. Stanley Jevons. Edited by his wife, H. A. Jevons. London: Macmillan. → Published posthumously. A remarkable Victorian document, showing Jevons’ intellectual development.

1905 The Principles of Economics: A Fragment of a Treatise on the Industrial Mechanism of Society and Other Papers. With an introduction by Henry Higgs. London and New York: Macmillan. → Published posthumously.

SUPPLEMENTARY BIBLIOGRAPHY

Black, R. D. Collison 1962 W. S. Jevons and the Economists of His Time. Manchester School of Economic and Social Studies 30:203–221.

Harrod, Roy Forbes 1951 The Life of John Maynard Keynes. London: Macmillan. → A paperback edition was published in 1963 by St. Martins.

Keynes, John Maynard (1933) 1951 William Stanley Jevons. Pages 225–309 in John Maynard Keynes, Essays in Biography. New York: Horizon. → A paper-back edition was published in 1963 by Norton.

Könekamp, Rosamond 1962 William Stanley Jevons (1835–1882): Some Biographical Notes. Manchester School of Economic and Social Studies 30:251–273.

Mays, Wolfe 1962 Jevons’ Conception of Scientific Method. Manchester School of Economic and Social Studies 30:223–249.

Mitchell, Wesley C. 1949 Lecture Notes on Types of Economic Theory. 2 vols. New York: Kelley. → See especially Chapters 2–8 in Volume 2.

Walras, Léon; and Cournot, A. (1873–1875) 1952 La correspondance complete de Cournot et Walras. ÉEconomic appliquée 5:5–33.

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Jevons, William Stanley

Jevons, William Stanley

(b. Liverpool, England, 1 September 1835; d. Hastings, England, 13 August 1882)

logic, economics, philosophy of science.

Jevon’s name is purportedly of Welsh origin, akin to Evans. His father, Thomas, was a notable iron merchant with an inventive trait, and his mother, Mary Anne Roscoe, belonged to an old Liverpool family of bankers and lawyers with a literary bent. The ninth of elevan children, Jevons was brought up, and always in spirit remained, a Unitarian. He was a timid, clever boy and not narrowly studious, showing unusual mechanical aptitude. At University College, London, he took science courses, and his prowess in chemistry was such that he was recommended, while still an undergraduate and only eighteen years of age, for the job of assayer at the newly established Australian mint. In part to help ease a shrunken family budget, he decided to interrupt his education and to accept the post, which carried the handsome remuneration of over £600 a year. In Sydney he cultivated his interests in meteorology, botany, and geology and published papers in these fields. After five years he renounced a prosperous future in Australia and went back to England to further, his education with a view to becoming an academic;he was already saying that “my forte will be found to lie. . .in the moral and logical sciences.”

The first subject Jevons concentrated on was political economy, which he felt he could transform. His early and sustained interest in economics must have owed something to two disjoint features of his youth: a family bankruptcy caused by a trade slump, and his having been involved in the physical creation of money. The fluctuations of the national economy always fascinated him.

Having earned his master’s degree at University College in 1863, Jevons was appointed junior lecturer at Owens College, Manchester, thus beginning a long association with that city. Two years later he became a part-time professor of logic and political economy at Queen’ College, Liverpool, and in 1866 the Manchester institution raised him to a full-time double professorship of “logic and mental and moral philosophy,” and of political economy. The following year Jevons married Harriet Ann Taylor, daughter of the founder and first editor of the Manchester Guardian, and the couple was soon enjoying the lively intellectual atmosphere of Victorian Manchester. They had three children, of whom one, Herbert stanley, became a well-known economist. Jevons was made a fellow of the royal society in 1872.

In 1876, tired of his teaching chores (he was a poor lecturer and hated to speak in public), Jevons moved to a less onerous but more prestigious professorship at University college, Four years later, he resigned, anxious to spend all his time writing, but his health had begun to deteriorate, despite many long recuperative vacations in England and Norway. A few weeks before his forty-seventh birthday he drowned (possibly as the result of a seizure) while swimming off the Sussex coast.

Jevons had a strong and almost visionary sense of his own destiny as a thinker, and he worried about its fulfillment. A prodigious worker, he sustained many side interests and was passionately fond of music. Among his tributary writings are articles on the Brownian movement, the spectrum, communications, muscular exertion, pollution, skating, and popular entertainment. He tried hard and successfully to improve his literary style, and his later writings are more concise and readable than his earlier ones.

Whether economics or the rationale of scientific methodology benefited more from Jevon’attention is still arguable, but it was certainly as an economist that he became a public figure. Ironically, his popular fame rested on two achievements that now seem slight or even misguided. The first was his book The Coal Question (1865), a homily about dwindling English fuel supplies in relation to rocketing future demands The work was Malthusian in the sense that he discussed industry and coal in much the terms that the earlier author had discussed population and food. It was a tract and obviously, as Keynes remarked, épatant. Gladstone, then chancellor of the Exchequer, was deeply impressed by the book, whose“grave conclusions” influenced his fiscal policy. A royal commission was subsequently appointed to look into the matter. Jevon’second achievement was the thesis, developed in the late 1870’ from tentative suggestions made by earlier writers, that trade cycles could be correlated with sunspot activity through agrometeorology and, at a further remove, through the price of wheat. It was an ingenous and inherently plausible argument, but the data could not be mainpulated pulated to yield convincing evidence and the theory has no standing today.

Jevons brought to economic theory a fruitful insistence on a mathematical framework with an abundance of statistical material to fill out the structure. He was a diligent collector and sifter of statistics, and his methods of presenting quantitative data showed insight and skill. He strongly advocated the use og good charts and diagrams (colored, if possible), which he said, were to the economist what fine maps are to the geographer. (At one time he toyed with a project to sell illustrated statistical information bulletins to businessmen.) He clarified certain concepts, particularly that of value, which he regarded as a function of utility, a property he wrote about with luminance. Indeed, this was his major contribution, and one that led to the explicit use of the calculus and other mathematical tools by economists.

Utility, said Jevons, “is a circumstance of things arising out of their relation to man’s requirements and that normally diminishes,” One of his favorite examples concerns bread, a daily pound of which, for a given person, has the “highest conceivable utility,” and he went on to show that extra pounds have progressively smaller utilities, illustrating that the “final degree of utility”declines as consumption rises. In effect he was arguing that the second derivative of the function Ua = U (Qa) where Ua is the total utility or satisfaction derived from the consumption of a in the amount Qa, is negative. This simple prrposition was quite new, for the classical theorists, including Marx, had analyzed value from the supply side only, whereas Jevon’analysis was from demand. Later writers were to recognize the necessity of both approaches. Incidentally, Jevons’approach was the forerunner of the idea of“marginal utility,” the first of the“marginal”concepts on which modern economics may be said to rest.

Jevons’work on price index-numbers deserves mention, as his setting them on a sound statistical footing enormously advanced understanding of changes in price and in the all-important value of gold.

Although some of Jevons’ ideas can be found inchoate in the works of his predeccessors Augustus Cournot and H. H. Gossen, and of his contemporaries Karal Menger and Léon Walras, he arrived at his theories independently and can be seen as a pathbreaker in modern economics. His stress on the subject as essentially a mathematical science was judicious, and he held no exaggerated notions about the role of mathematics-he had observed, he said slyly, that mathematical students were no better than any others when faced with real-life problems.

Economics and logic have traditionally been associated in England, and Jevons belongs to the chain of distinguished thinkers, from John Stuart Mill to Frank Ramsey, who are linked to both disciplines. He was opposed to Mill in divers particulars, and at times he looked upon the older man’s deep influence on the teaching of logic as hardly short of disastrous. Mill’s mind, he once averred, was “essentially illogical,” and Jevons eagerly seized on Boole’s remarkable new symbolic logic to show up what he deemed the vastly inferior warmed-over classical logic of Mill. Jevons actually improved on Boole in some important details, as, for instance, in showing that the Boolean operations of subtraction and division were superfluous. Whereas Boole had stuck to the mutually exclusive “either-or,” Jevons redefined the symbol+ to mean “either one, or the other, or both,”This change, which was at once accepted and became permanent, made for greater consistency and flexibility. The expression a+a, which was an uninterpretable nuisance in the Boolean scheme, now fell into place, the sum being a.

At the same time Jevons deprecated certain aspects of Boole’s work. He thought it too starkly symbolic and declared that “the mathematical dress into which he [Boole] threw his discoveries is not proper to them, and his quasi-mathematical processes are vastly more complicated than they need have been”mdash;an extravagant statement, even in the light of Jevons’ own logic. Indeed, some of Javons’ writings about Boole’s system, and especially his worries about the discrepancies between orthodox and Boolean algebras, suggest that he did not fully grasp Boole’s originality, potential, and abstractness. Nevertheless, he can certainly be reckoned a leading propagandist for Boole, Particularly among those who could not understand, or who would not brook, Boole’s logic. Moreover, Jevons was led through Boole’s ideas to some original work on a logical calculus.

Jevons’logic of inference was dominated by what he called the substitution of similars, which expressed “the capacity of mutual replacement existing in any two objects which are like or equivalent to a sufficient degree.” This became for him “the great and universal principle of reasoning” from which “all logical processes seem to arrange themselves in simple and luminous order.”It also allowed him to develop a special equational logic, with which he constructed various truth-tablelike device for handling logical problems. He did not foresee that a truth-table calculus could be developed as a self-contained entity, but he was able to devise a logic machine—a sort of motional from of the later digrammatic scheme of John Venn. Jevons’’ “logical piano”(as he eventually called it in preference to his earlier terms “abacus,”“abecedarium” and “alphabet”) was built for him by a Salfford clockmaker. It resembled a small upright piano, with twenty-one;-keys for classes and operations in an equational logic. Four terms, A, B, C, and D, with their negations, in binary combinations, were displayed in slots in front and in back of the piano; and the mechanism allowed for classification, retention, or rejection, depending upon what the player fed in via the keyboard. The keyboard was arranged in an equational form, with all eight terms on both left and right and a “copula”key between them. The remaining four keys were, on the extreme left, “finis” (clearance) and the inclusive “or,” and, on the extreme right, “full stop”(output) and the inclusive “or again,”, In all 216 (65, 536) logical selections were possible.

The machine earned much acclaim, especially after its exhibition at the Royal Society in 1870. At present it is on display in the Oxford Museum of the History of Science. Although its principal value was as an aid to the teaching of the new logic of classes and propositions, it actually solved problems with superhuman speed and accuracy, and some of its features can be traced in modern computer designs.

Jevons’various textbooks on logic sold widely for many decades, and his Elementary Lessons in Logic (London, 1870) was still in print in 1972. Moreover, he considered his ambitious work on the rationale of science to be an extension of his logic into a special field of human endeavor. His biggest and most celebrated book, The Principles of Science, is firmly rooted in Jevonian logic and contains practically all his ideas on, and contributions to, the subject. Inescapably, the matter of induction, the basis of scientific method and the bugbear of scientific philosophy is lengthily explored and analyzed. Jevons confidently declared the “induction is, in fact, the inverse operation of deduction.” Such a statement—in one sense a truism and in another a travesty—might be thought a feeble beginning for a study of the how and why of science, but Jevons acquits himself admirably. He does not confuse the formal logic of induction with the problems of inductive inference in the laboratory, and he is obviously under no illusions about the provisional nature of all scientific “truth.”

Nineteenth-century English scholars, inspired by the phenomenal explicatory and material success of science, had been taking an increasing interest in its philosophy. John Stuart Mill and William Whewell are particularly associated with these early studies; and in Jevons’view their work contained serious flaws. He thought that Mill, first, expected too much of science as a key to knowledge of all kinds and, second that he was overly respectful of Bacon’view of science as primarily the collection and sortation of data. His criticism of Whewell centered on that writer’apparent assumption that exact knowledge is a reality attainable by scientific patience.

Jevons was perhaps the first writer to insist that absolute precision, whether of observation or of correspondence between theory and practice, is necessarily beyond human reach. Taking a thoroughly modern position, Jevons held that approximation was of the essence, adding that “in the measure of continuous quantity, perfect correspondence must be accidental, and should give rise to suspicion rather than to satisfaction.” He also felt that causation was an overrated if not dangerous concept in science, and that what we seek are logically significant interrelations. All the while, he said, the scientist is farming hypotheses, checking them against existing information, and then designing experiments for further support. There can be no cut-and hyphen;dried conclusion to most investigations and no guarantee that correct answers can be issued. The scientist must act in accordance with the probabilities associable with rival hypotheses, which probabilities or, as many would prefer to say today, likelihoods, constitute the decision data. Thus “the theory of probability is an essential part of logical method, so that the logical value of every inductive result must be determined consciously or unconsciously, according to the principles of the inverse method of probability.” An entire chapter of The Principles is devoted to direct probability and another to inverse probability.

As a probabilist Jevons was fundamentally a disciple of Laplace, or at least of Laplace as reshaped by Jevons’ own college teacher and mentor Augustus De Morgan—that is to say, he was a subjectivist. Probability, he maintained, “belongs wholly to the mind” and “deals with quantity of knowledge.” Yet he was careful to emphasize that probability is to be taken as a measure, not of an individual’s belief, but of rational belief—of what the perfectly logical man would believe in the light of the available evidence. In espousing this view, Jevons sidestepped Boole’s disturbing reservations about subjectivism—mainly because he had difficulty grasping them. Writing to Herschel, he stated, frankly: “I got involved in Boole’s probabilites, which I did not thoroughly understand. . . . The most difficult points ran in my mind, day and night, till I got alarmed. The result was considerable distress of head a few days later, and some sings of indigestions.” In general Jevons was silent about the movement toward a frequential theory of probability that was growing out of the work of Leslie, Ellis, and Poisson, as well as that of his contemporary, Venn.

To the modern reader, however, Jevons may seem altogether too self-assured in this notoriously treacherous field. For example, he wholeheartedly accepted Laplace’s controversial rule of succession and offered a naive illustration of its applicability: Observing that of the sixty-four chemical elements known to date (Jevons was writing in 1873) fifty are metallic, we say that the quantity (50+1)-(61+2) equil 17-22is the probability that the next elements discovered will be a metal. To the frequentist, insistent on a clearly delineated sample space, this statement is almost wholly devoid of meaning. Another, more bizarre example of his naive Laplaceanism is his contention that the proposition “a platythliptic coefficient is positive” has, because of our complete ignorance, a probability of correctness of 1aol-2. Boole had rightly objected to this sort of thing and would agree with Charles Terrot that such a probability has the numeric but wholly indeterminate value of 0-0. To understand Jevons’ position, however, we must bear in mind that the prestige of Laplace, especially in this area, was then enormous.

Curiously, in discoursing on what he calls“the grand object of seeking to estimate the probability of future events from past experience,”Jevons made only one casual and unenlightening reference to Thomas Bayes, who, a century earlier, had been the first to attempt a coherent theory of inverse probability. Today the implication of Bayes’s work from the subject of lively discussion among probabilists.

Some of the most illuminating sections of The Principles of Science are those dealing with technical matters, such as the methodology of measurement, the theory of errors and means, and the principle of least squares. Yet the books offers only a shallow treatment of the logic of numbers and arithmetic, and it has been criticized for the absence of any serious discussion of the social and biological science. By and large, however, The Principles is something of a landmark in the bleak country of nineteenth-century philosophy of science.

BIBLIOGRAPHY

I. Original Works. According to Harriet Jevons’ bibliography (see below), Jevons’ first appearance in print was a weather report (24 Aug. 1856) in the Empire, a Sydney, Australia, newspaper, for which he wrote weekly reports until 1858. His first publication in a scholarly journal was “On the Cirrus Form of Cloud, With Remarks on Other Forms of Cloud,” in London, Edinburgh and Dublin Philosophical Magazine,14 (July 1857), 22-35. His account of the logical piano is “On the Mechanical performance of Logical Inference,” in Philosophical Transactions of the Royal Society,160 (1870), 497-518.

His books, all published in London, include Pure Logic (1863); The Coal Question (1865); The Theory of Political Economy (1871); The Principles of Science (1874); Studies in Deductive Logic (1880); The State in Relation to Labour (1882); Methods of Social Re-Form (1883); Investigations in Currency and Finance (1884); and Principles of Economics (1905). The last three were published posthumously, and the very last is a fragment of a large work that he was writing at the time of his death.The Principles of Science, A Treatise on Logic and Scientific Method the frontispiece of which is an engraving of the logical piano, is available as a paperback reprint (New York, 1958).

For information on the 1952 exhibition of Jevons’ works at the University of Manchester, see Nature,170 (1952), 696. The library of that university has Jevons’ economic and general MSS, and Wolfe Mays of the Department of Philosophy owns the philosophic and scientific MSS; much of this material is still unpublished.

II. Seconndary Literature. No full biography exists. The primary source is Harriet A. Jevons, Letters and Journal of W. Stanley Jevons (London, 1886), with portrain and bibliography. See also the obituary by the Reverend Robert Harley in Proceedings of The Royal Society,35 (1883), i-xii. Jevons’ granddaughter, Rosamund Köne-kamp, contributed “Some Biographical Notes” to Manchester School of Economics and Social Studies,30 (1962), 250-273. For a modern view of his logic, see W. Mays and D. P. Henry, “Jevons and Logic,” in Mind, 62 (1953), 484-505. The logic contrivances are described and placed in historic perspective in Martin Gardner, Logic Machines and Diagrams (New York, 1958). Jevonsrsquo; economics is reviewed in J. M. Keynes, Essays in Biography, 2nd ed. (London, 1951); and, more formally, in E. W. Eckard, Economics of W. S. Jevons (Washington, D.C., 1940); both of the foregoing also contain biographical material. His contemporary influence is discussed in R.D.C. Black, “W. S. Jevons and the Economists of His Time,” in Manchester School of Economics and Social Studies,30 (1962), 203-221. Ernest Nagel has written a preface on Jevons’ philosophy of science for the paperback ed. of Principles of Science. See also W. Mays, “Jevons’s Conception of Scientific Method,” in Manchester School of Economics and Social Studies, 30 (1962), 223-249.

Norman T. Gridgeman

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William Stanley Jevons

William Stanley Jevons

The English economist, logician, and statistician William Stanley Jevons (1835-1882) did pioneering work in marginalist economics, index numbers of prices, and economic fluctuations.

The son of a merchant, W. S. Jevons was born in Liverpool on Sept. 1, 1835. At age 15 he went to secondary school in London and then to the University of London. His excellent record in chemistry led to an offer as assayer to the Royal Mint in Sydney, Australia. While there, from 1854 to 1859, he read widely and showed increasing concern for social problems. On his return to England, he resumed his studies, receiving the bachelor's and master's degrees from the University of London.

Jevons taught at Owens College, Manchester, from 1863 to 1876, when he became professor of political economy at University College, London. He resigned in 1880 to devote all of his energies to writing. He married Harriet Ann Taylor, daughter of the founder of the Manchester Guardian, in 1867. Despite ill health, his accomplishments, before he drowned at the age of 46, were highly impressive. However, he did not receive the recognition which the originality and quality of his work merited.

Two scholarly papers presented in 1862 foreshadowed Jevons's later work on the mathematical theory of economics and on business fluctuations. His first important publication, A Serious Fall in the Value of Gold (1863), was followed by Pure Logic (1864), The Coal Question (1865), Elementary Lessons in Logic (1870), The Theory of Political Economy (1871), Principles of Science (2 vols., 1874 and 1877), Money and the Mechanism of Exchange (1875), and The State in Relation to Labour (1882). At the time of his death he was working on Principles of Economics; it was published in incomplete form in 1905 and does not represent what would have been the full fruition of his thought.

Jevons was a utilitarian, treating economics as a calculus of pleasure and pain. The degree of utility of a commodity is some continuous mathematical function of the quantity available. The more one has, the less the utility of the additional unit. Here was the solution of the paradox that had troubled classical economists as well as Karl Marx—diamonds bring a higher price than water, even though water seems more useful. The marginal utility of a gallon of water is slight because much other water is available. The labor theory of value no longer ruled. But labor as a cost of production influences the quantity supplied and thereby affects the final degree of utility of amounts offered on the market.

Jevons found the economic theory of David Ricardo and John Stuart Mill, that value rests upon cost of production, to be unacceptable, but he did not succeed in getting wide acceptance of his own advances in economic theory. As a writer on practical problems of the time and on issues of social reform, however, he received considerable recognition for his work on applied economics and statistics: fluctuations of prices, business crises, and money and banking. Jevons developed concepts of market processes and economic equilibrium, using diagrams of the general type familiar to students of economics. He was a free-trader, doubting the effectiveness of trade unionism to raise the earnings of labor, and placed hope in cooperation.

Further Reading

Letters and Journal of W. S. Jevons was edited by his wife (1886).E. W. Eckard, Economics of W. S. Jevons (1940), includes a biography as well as a description of Jevons's theories.

Additional Sources

Peart, Sandra, The economics of W.S. Jevons, New York: Routledge, 1996. □

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Jevons, W. S.

Jevons, W. S. (1835–82). Distinguished neo-classical economist. Jevons was born in Liverpool, and educated in Liverpool and London. After studying chemistry at University College, London, and working as an assayer in Australia, he returned to University College in 1859 to study political economy, philosophy, and mathematics. From 1863 he was tutor, lecturer, and then professor at Owens College, Manchester, moving, in 1876, to a chair at University College, London (until 1880). He married the daughter of the founder of the Manchester Guardian, and drowned in the sea near Hastings. Jevons had wide interests in political economy, from currency and finance to the relation of sunspots to business cycles. His principal contribution, however, is his work on the marginal utility theory of value (Theory of Political Economy, 1872), the introduction of marginal analysis marking ‘the true dividing line between classical theory and modern economics’.

Margaret Wilkinson

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JOHN CANNON. "Jevons, W. S." The Oxford Companion to British History. 2002. Encyclopedia.com. 28 Jul. 2016 <http://www.encyclopedia.com>.

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Jevons, William Stanley

William Stanley Jevons (jĕv´ənz), 1835–82, English economist and logician. After working in Australia as assayer to the mint, he taught at Owens College, Manchester, and University College, London. His major contribution to economics was his marginal utility theory of value; Jevons held that value was determined by utility, and he demonstrated the relationship in mathematical terms. The Theory of Political Economy (1871) was his chief theoretical work. His practical application of economics in The Coal Question (1865) influenced government action. In General Mathematical Theory of Political Economy (1862), he demonstrated his belief in the application of mathematics to economic theory. His several texts include Pure Logic (1863) and The Principles of Science (1874).

See his Letters and Journal (ed. by his wife, 1886).

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