Clifford W(illiam) K(ingdon) (1845–79), British mathematician and philosopher. Educated at King’s College, London, and Trinity College, Cambridge, he began giving public lectures in 1868, when he was appointed a fellow of Trinity, and in 1870 became professor of applied mathematics at University College, London. His academic career ended prematurely when he died of tuberculosis. Clifford is best known for his rigorous view on the relation between belief and evidence, which, in ‘The Ethics of Belief,’ he summarized thus: ‘It is wrong always, everywhere, and for anyone, to believe anything on insufficient evidence.’ He gives this example. Imagine a shipowner who sends to sea an emigrant ship, although the evidence raises strong suspicions as to the vessel’s seaworthiness. Ignoring this evidence, he convinces himself that the ship’s condition is good enough and, after it sinks and all the passengers die, collects his insurance money without a trace of guilt. Clifford maintains that the owner had no right to believe in the soundness of the ship. ‘He had acquired his belief not by honestly earning it in patient investigation, but by stifling his doubts.’ The right Clifford is alluding to is moral, for what one believes is not a private but a public affair and may have grave consequences for others. He regards us as morally obliged to investigate the evidence thoroughly on any occasion, and to withhold belief if evidential support is lacking. This obligation must be fulfilled however trivial and insignificant a belief may seem, for a violation of it may ‘leave its stamp upon our character forever.’ Clifford thus rejected Catholicism, to which he had subscribed originally, and became an agnostic. James’s famous essay ‘The Will to Believe’ criticizes Clifford’s view. According to James, insufficient evidence need not stand in the way of religious belief, for we have a right to hold beliefs that go beyond the evidence provided they serve the pursuit of a legitimate goal. See also EPISTE- MOLOGY, EVIDENTIALIS. M.St.