Frank Ramsey 1903 – 1930

Frank Plumpton Ramsey was a British mathematician, logician, and philosopher of extraordinary precocity who, in a career cut short by his death at twenty-six, made foundational contributions to mathematical logic, the philosophy of probability, the philosophy of language, and economics. His paper Truth and Probability set out the first comprehensive subjectivist theory of probability and a pragmatist account of belief, while his work on the foundations of mathematics and on Wittgenstein's Tractatus shaped Cambridge analytic philosophy in his lifetime. His influence has only grown since his early death.

Frank Plumpton Ramsey was born in 1903 in Cambridge, the elder son of A. S. Ramsey, master of Magdalene College and a mathematician. He went up to Trinity College in 1920 and in his undergraduate years translated Wittgenstein's Tractatus Logico-Philosophicus into English with C. K. Ogden, contributing notes that Wittgenstein later said had set him thinking again. Elected a fellow of King's at twenty-one, he held the post until his sudden death.

His extraordinary output was confined to half a dozen papers, most of them written in his late twenties: 'The Foundations of Mathematics' (1925), 'Universals' (1925), 'Truth and Probability' (1926), 'Facts and Propositions' (1927), 'A Mathematical Theory of Saving' (1928), and 'On a Problem of Formal Logic' (1930), which founded what is now called Ramsey theory. He converted Keynes from a logical to a subjective theory of probability, did pioneering work on optimal taxation and the rate of saving, and drafted but did not finish the projected book On Truth.

Ramsey gave subjective Bayesianism its first rigorous axiomatic basis, framed truth deflationism in the redundancy theory, formulated the device now called Ramsey-sentencing for the elimination of theoretical terms, and re-analyzed Russell's theory of universals. He died at Guy's Hospital in London in January 1930 at the age of twenty-six, after surgery for a liver infection.