Francis Ysidro Edgeworth
Born(1845-02-08)8 February 1845
Died13 February 1926(1926-02-13) (aged 81)
Oxford, Oxfordshire, England
Alma materTrinity College Dublin
Balliol College, Oxford
AwardsGuy Medal (Gold, 1907)
Scientific career
FieldsPhilosophy, political economist

Francis Ysidro Edgeworth FBA (8 February 1845 – 13 February 1926) was an Anglo-Irish philosopher and political economist who made significant contributions to the methods of statistics during the 1880s. From 1891 onward, he was appointed the founding editor of The Economic Journal.


Ysidro Francis Edgeworth – the order of his forenames later reversed – was born in Edgeworthstown, County Longford, Ireland, the son of Francis Beaufort Edgeworth and his wife, Rosa Florentina, daughter of exiled Catalan general Antonio Eroles.[1][page needed] Francis Beaufort Edgeworth, when "a restless philosophy student at Cambridge on his way to Germany", had met Rosa, a teenage Spanish refugee, on the steps of the British Museum, and they subsequently eloped. Francis Beaufort Edgeworth was the son of politician, writer, and inventor Richard Lovell Edgeworth (father also of the writer Maria Edgeworth), by his fourth wife, the botanical artist and memoirist Frances Anne, daughter of the Anglican clergyman and geographer Daniel Augustus Beaufort, of French Huguenot origin. The Edgeworth family, which settled in Ireland in the 1580s, was distinguished, descending from Francis Edgeworth, joint Clerk of the Crown and Hanaper in 1606, who inherited a fortune from his brother Edward Edgeworth, Bishop of Down and Connor. Richard Lovell Edgeworth was a descendant, through his mother, of the English judge Sir Salathiel Lovell.

The youngest of seven children, Edgeworth did not attend school, but was educated by private tutors at the Edgeworthstown estate until he reached the age to enter university.[2]

As a student at Trinity College Dublin he studied classics getting a scholarship in 1863 and graduating in 1865, and at Balliol College, Oxford, Edgeworth studied ancient and modern languages. A voracious autodidact, he studied mathematics and economics only after he had completed university. He qualified as a barrister in London in 1877 but did not practise.[3]

On the basis of his publications in economics and mathematical statistics in the 1880s, Edgeworth was appointed to a chair in economics at King's College London in 1888, and in 1891, he was appointed Drummond Professor of Political Economy at Oxford University. In 1891, he was also appointed the founding editor of The Economic Journal. He continued as editor or joint-editor until his death 35 years later.[4]

The Royal Statistical Society awarded him the Guy Medal in Gold in 1907. Edgeworth served as the president of the Royal Statistical Society, 1912–14. In 1928, Arthur Lyon Bowley published a book entitled and devoted to F. Y. Edgeworth's Contributions to Mathematical Statistics.

Contributions to economics

Edgeworth was a highly influential figure in the development of neo-classical economics. He was the first to apply certain formal mathematical techniques to individual decision making in economics. He developed utility theory, introducing the indifference curve and the famous Edgeworth box, which is now familiar to undergraduate students of microeconomics. He is also known for the Edgeworth conjecture, which states that the core of an economy shrinks to the set of competitive equilibria as the number of agents in the economy gets larger. In statistics, Edgeworth is most prominently remembered by having his name on the Edgeworth series.

Though Edgeworth's economic ideas were original and in depth, his contemporaries frequently complained of his manner of expression for lack of clarity. He was prone to verbosity and coining obscure words without providing definition for the reader.[5]

Mathematical Psychics (1881)

His most original and creative book on economics was Mathematical Psychics: An Essay on the Application of Mathematics to the Moral Sciences, published in 1881 at the beginning of his long career in the subject.

In the book, he criticised Jevons's theory of barter exchange, showing that under a system of "recontracting" there will be, in fact, many solutions, an "indeterminacy of contract". Edgeworth's "range of final settlements" was later resurrected by Martin Shubik (1959) to be the game-theoretic concept of "the core".[6] The book contained the first instance of the indifference curve, as level sets of the generalised utility function, U(xyz, ...).[6]

The book was notoriously difficult to read. He frequently referenced literary sources and interspersed the writing with passages in a number of languages, including Latin, French and Ancient Greek. The mathematics was similarly difficult, and a number of his creative applications of mathematics to economic or moral issues were judged as incomprehensible. However, one of the most influential economists of the time, Alfred Marshall, commented in his review of Mathematical Psychics:[7]

This book shows clear signs of genius, and is a promise of great things to come... His readers may sometimes wish that he had kept his work by him a little longer till he had worked it out a little more fully, and obtained that simplicity which comes only through long labour. But taking it as what it claims to be, 'a tentative study', we can only admire its brilliancy, force, and originality.

Edgeworth's close friend, William Stanley Jevons, said of Mathematical Psychics:[8]

Whatever else readers of this book may think about it, they would probably all agree that it is a very remarkable one.... There can be no doubt that in the style of his composition Mr. Edgeworth does not do justice to his matter. His style, if not obscure, is implicit, so that the reader is left to puzzle out every important sentence like an enigma.
Papers relating to political economy, 1925

Edgeworth's limit theorem

Main article: Edgeworth's limit theorem

When the number of agents in an economy increases, the degree of indeterminacy is reduced. In the limit case of an infinite number of agents (perfect competition), the set of possible contract becomes fully determinate and identical to the 'equilibrium' of economists. The only way of resolving this indeterminacy of contract would be to appeal to the utilitarian principle of maximising the sum of the utilities of traders over the range of final settlements.

International trade

He was the first one to use offer curves and community indifference curves to illustrate its main propositions, including the "optimal tariff".

Taxation paradox

Taxation of a good may actually result in a decrease in price.

He set the utilitarian foundations for highly progressive taxation, arguing that the optimal distribution of taxes should be such that 'the marginal disutility incurred by each taxpayer should be the same' (Edgeworth, 1897).

Monopoly pricing

In 1897, in an article on monopoly pricing, Edgeworth criticised Cournot's exact solution to the duopoly problem with quantity adjustments as well as Bertrand's "instantly competitive" result in a duopoly model with price adjustment. At the same time, Edgeworth showed how price competition between two firms with capacity constraints and/or rising marginal cost curves resulted in indeterminacy. This gave rise to the Bertrand–Edgeworth model of oligopoly.

Marginal productivity theory

Edgeworth criticised the marginal productivity theory in several articles (1904, 1911), and tried to refine the neo-classical theory of distribution on a more solid basis. Although his work in questions of war finance during World War I was original, they were a bit too theoretical and did not achieve the practical influence he had hoped.



Individual works

Also available as: Edgeworth, F.Y. (1995), "Women's Wages in Relation to Economic Welfare", in Humphries, Jane (ed.), Gender and economics, Aldershot, England Brookfield, Vermont, USA: Edward Elgar, pp. 99–112, ISBN 9781852788438.


  1. ^ Barbe 2010.
  2. ^ Barbe, Lluis (2010), Francis Ysidro Edgeworth: A Portrait With Family and Friends, Edward Elgar Publishing, p. 1, ISBN 9781849803229, His name was actually Ysidro Francis Edgeworth, but his family and friends called him Francis or Frank, and when he started publishing in 1876 he transposed his Christian names.
  3. ^ Barbe (2010), p. 85: "The year 1877 was a productive year for Edgeworth in earning titles. He acquired the degree of Master of Arts from Oxford and was called to the bar by the Inner Temple. This means that he had successfully completed his studies at the professional level. However, by then he had decided not to pursue a legal career."
  4. ^ O'Connor, John J.; Robertson, Edmund F., "Francis Ysidro Edgeworth", MacTutor History of Mathematics Archive, University of St Andrews
  5. ^ Stigler, Stephen M. (1978), "Francis Ysidro Edgeworth, Statistician", Journal of the Royal Statistical Society, Series A, 141 (3): 287–322, doi:10.2307/2344804, JSTOR 2344804. See in particular Section 3, "Edgeworth's Style", pp. 292–293.
  6. ^ a b "Francis Ysidro Edgeworth". Archived from the original on 9 February 2005. Retrieved 9 February 2005.
  7. ^ "Alfred Marshall (1881) "Review of Edgeworth's Mathematical Psychics"". Archived from the original on 10 August 2012. Retrieved 20 June 2010.
  8. ^ W.S. Jevons's "Review of Mathematical Psychics", 1881 Archived 1 February 2016 at the Wayback Machine at

Further reading