Edgeworth, Francis Ysidro [originally Ysidro Francis] 1845-1926, economist and statistician, was born at Edgeworthstown, co. Longford, 8 February 1845, the fifth son of Francis Beaufort Edgeworth, by his Spanish wife, Rosa Florentina Eroles. His father was the sixth son of the author Richard Lovell Edgeworth [qv.], and half-brother of the novelist Maria Edgeworth [qv.] and of Anna Edgeworth, who married Thomas Beddoes [qv.]. Francis Ysidro Edgeworth thus had an aunt (Maria) born in 1767 and already well known in the eighteenth century, and a first cousin—Thomas Lovell Beddoes, the poet [qv.]—born in 1803. Apart from descendants of the eldest son of Richard Lovell Edgeworth living in the United States, Edgeworth, who was himself unmarried, was the last representative of his grandfather in the male line, and succeeded in 1911 to the family estate of Edgeworthstown.
     Edgeworth, whose father died when he was two years old, was educated at home until he went, at the age of seventeen, to Trinity College, Dublin. Thence he passed to Oxford as a scholar of Magdalen Hall, proceeding from there to Balliol College, where he obtained a first class in literae humaniores in 1869. After taking his degree, he spent some years in London with straitened means, studying and writing and lecturing on the moral sciences at King's College, London, where, in 1888, he was appointed professor of political economy, becoming Tooke professor of economic science and statistics in 1890. Meanwhile, he had been called to the bar by the Inner Temple in 1877, but never practised. In 1891 he succeeded J. E. Thorold Rogers [qv.] as Drummond professor of political economy at Oxford and was elected a fellow of All Souls College, which became his principal home for the rest of his life. He resigned his chair in 1922, and was then made emeritus professor.
     It seems likely that Edgeworth's interest in the moral sciences was first stimulated at Balliol by Benjamin Jowett, of whom he had been a favourite pupil. But the most important and definite influences on his economic thought were first of all William Stanley Jevons [qv.], who was a near neighbour in Hampstead in Edgeworth's early years in London, and subsequently Alfred Marshall [qv.].
     Edgeworth approached the moral sciences with a strong mathematical bias, and his main contributions to these subjects were along formal and highly abstract lines. His first book, New and Old Methods of Ethics, mainly a commentary on Henry Sidgwick's Methods of Ethics (1874), was published in 1877. His second volume, entitled Mathematical Psychics, an Essay on the Application of Mathematics to the Moral Sciences (1881), was not only one of his most original and important contributions to science, but indicated in its title the field to be occupied by nearly all his work. Apart from Metretike, or the Method of Measuring Probability and Utility (1887), Edgeworth published no book during the remaining thirty-nine years of his life, but contented himself with a long series of contributions to learned journals and some pamphlets published during the European War. A list of twenty-five publications between 1877 and 1887 is given in an appendix to Metretike; twenty-nine items bearing on the theory of probability, published between 1883 and 1921, are given in the bibliographical appendix to J. M. Keynes's Treatise on Probability (1921). His principal contributions to economics, amounting to thirty-four papers and seventy-five reviews, were reprinted in his Papers relating to Political Economy, published by the Royal Economic Society in 1925; and seventy-four papers and nine reviews on statistical theory are cited in A. L. Bowley's memoir entitled Edgeworth's Contributions to Mathematical Statistics, published after his death by the Royal Statistical Society (1928).
     A great part of Edgeworth's time for the last thirty-five years of his life was occupied with the editorship of the Economic Journal, the quarterly organ of the Royal Economic Society. He was its first editor from its commencement in 1891, and designed and moulded the form which the Journal took during subsequent years. He was continuously connected with it, first as editor, then as chairman of the editorial board, and finally as joint editor with J. M. Keynes, from the first issue in March 1891 down to the day of his death, which took place at Oxford, 13 February 1926. This work kept him in close touch not only with English but also with continental and American economists. For many years he played a large part in maintaining the contacts of the world of economic science in various countries. He was president of the economics section of the British Association in 1889 and president of the Royal Statistical Society from 1912 to 1914. He was elected F.B.A. in 1903.
     Since Edgeworth never attempted a systematic treatise on economics, his influence was overshadowed by that of Alfred Marshall. But, whereas Marshall deliberately shrank from highly abstract attempts to formalize the main propositions of the subject, Edgeworth became in many directions the parent of the strictly formal and mathematical treatment of economic theory in English-speaking countries. He was principally interested in those parts of the subject which were susceptible to development somewhat on the lines of symbolic logic, and in the metrical aspects of the moral sciences which seemed to lend themselves to a quasi-mathematical treatment. He was very fond of elaborate arithmetical illustrations, drawn so far as possible from actual facts, of highly abstract economic and statistical theories. The greater part of his work can be classified under five applications of mathematical psychics (to use his own term): to the measurement of utility or ethical value; to the algebraic or diagrammatic determination of economic equilibriums; to the measurement of belief or probability; to the measurement of evidence or statistics; and to the measurement of economic value or index numbers.
     That Edgeworth never systematized his numerous and important contributions to these various subjects may perhaps be attributed not wholly to his temperament, but also to a gradually growing doubt as to the validity of pushing too far the analogy between psychics and physics which had seemed to him so attractive and fruitful at the opening of his scientific life.
     Edgeworth spent most of his life in college and in clubs. Although much in the company of his fellow men, he was essentially reserved and recluse. He mingled an old-fashioned classical culture with his highly abstract technique, and his style of writing, although sometimes eccentric and sometimes obscure, often has much aesthetic attraction. He was fond of appealing to authority and preferred to state his opinions inconclusively. This inconclusiveness, together with his reserve and his obscurity, detracted from his value as a teacher, and he developed no school of economists during his long tenure of the Oxford chair. He was a man of the highest gifts and greatness of nature which failed in some way of complete fruition.

     J. M. Keynes, Memoir of F. Y. Edgeworth, first published in the Economic Journal, March 1926, and republished with some revision in Essays in Biography, 1933
     A. L. Bowley, Francis Ysidro Edgeworth in Econometrica, April 1934
     personal knowledge.

Contributor: J. M. Keynes.

Published: 1937