William Stanley Jevons 1835 – 1882

William Stanley Jevons was an English economist, logician, and philosopher of science and one of the chief figures of the marginal revolution in economics. Trained at University College London, he held chairs at Owens College, Manchester, and later at his old university. His Theory of Political Economy, published in 1871, advanced the marginal utility theory of value, while The Principles of Science set out a Boolean logic of propositions and a probabilistic account of inductive inference. He drowned at forty-six while bathing on the south coast of England.

William Stanley Jevons was born at Liverpool in September 1835, the son of an iron merchant whose firm went bankrupt in the panic of 1848. He read mathematics and chemistry at University College London, interrupted his studies to serve as assayer at the new Sydney Mint from 1854 to 1859, and returned to take his bachelor's and master's at UCL. He was tutor and then professor of logic and political economy at Owens College, Manchester, from 1865 to 1876, and finally professor of political economy at UCL until his retirement from teaching in 1880.

His principal works are Pure Logic (1864), 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), and the posthumous Investigations in Currency and Finance. He built a 'logical piano', a mechanical inference engine still preserved at Oxford, and in The Coal Question gave an early formulation of what is now called the Jevons paradox.

Jevons reduced economic value to a calculus of marginal or 'final' utility and so, simultaneously with Carl Menger and Léon Walras, founded the marginalist revolution that displaced classical Ricardian theory. He also developed an equational logic of identity and proposed a controversial sunspot theory of the trade cycle. He drowned while bathing at Bulverhythe near Hastings in August 1882, aged forty-six.