British philosopher, a leading figure in modern analytic philosophy.
Born in London, the son of a doctor, Moore was educated at Dulwich College and Trinity College, Cambridge, where he served as a fellow from 1898 to 1904. As a man of independent means he worked privately at philosophy before returning to Cambridge as a lecturer (1911–25) and later as professor (1925–39) of philosophy.
It was Moore, Bertrand Russell declared, who in 1903 forced him to change his mind on ‘fundamental questions’. He led the revolt against the prevalent Hegelianism of their student days, objecting that it was inapplicable to the familiar world of ‘tables and chairs’. With Moore, philosophical problems arose not from his contemplation of the world, from the work of scientists, or even from his own imagination but, he confessed, exclusively from the puzzling writings of other philosophers. What could they have meant, he repeatedly asked himself, when, like J. E. McTaggart (1866–1925), they proclaimed time to be unreal? Or, like George Berkeley (1685–1753), when they insisted that matter was unreal? In response Moore offered two of his best-known papers, ‘A Defence of Common Sense’ (1923) and ‘A Proof of an External World’ (1939). Moore pioneered the techniques of philosophical analysis, in which he was followed by many of his younger colleagues. He also wrote extensively on problems of perception, insisting throughout his life that sense data are directly perceived.
Moore's best-known work, Principia Ethica (1903), exercised, through his contact with the Bloomsbury group, more than a strictly philosophical influence. He argued that good was a simple, indefinable, unanalysable, and non-natural property. Thus, any attempt to define it would lead to some form of the naturalistic fallacy. It was still possible, he insisted, to identify certain things as pre-eminently good. These he declared to be ‘personal affection and aesthetic enjoyments’, values seized upon and deployed in unexpected ways by several of his more worldly Bloomsbury friends.
Moore's personality was marked by a passionate commitment to philosophy, a remarkable honesty, and a simplicity bordering on innocence. Only once, Russell declared, had he known Moore to lie, when he had asked him if he always spoke the truth. ‘No’, Moore replied. Russell also described the familiar sight of Moore unavailingly attempting to light his pipe while engaging in philosophical discussion. Match after match would be struck, leaving Moore eventually still talking but holding an unlit pipe, an empty matchbox, and several burnt fingers.