F.Y. Edgeworth’s Mathematical Psychics and his Utilitarianism: The Derivation from the ‘Sidgwick-Barratt Controversy’*

The purpose of this article is to demonstrate that Edgeworth’s Mathematical Psychics (1881) has been influenced by various intellectual contemporaries through the ‘Sidgwick-Barratt Controversy’. Under the influence of Barratt, Edgeworth admitted the physical methods of ethics; which is clear from his adoption of the ‘Fechner’s Law’ to measure the quantity of pleasure. Through the analysis of the contract between egoistic agents, Edgeworth also attempted to prove the need of utilitarianism as the solution to Sicgwick’s ‘Dualism of Practical Reasons’. Since Edgeworth asserted that the capacity for pleasure is different among people, criticizing ‘equality’ tacitly implied in utilitarianism, he admitted ‘exact Utilitarianism’ which allowed unequal distribution as the ‘distributive justice’ for the greatest happiness of the society. Thus Edgeworth’s Mathematical Psychics is not only the economic but also ethical work influenced by ‘Sidgwick-Barratt Controversy’.