Ludwig Wittgenstein

(Austrian-born philosopher, 1889–1951). Wittgenstein was a central figure for the development of British analytic and ordinary language philosophy, though some elements of his thought situate him uneasily within that tradition. A distinction is commonly made (not least by Wittgenstein himself) between the austere, early Wittgenstein of the Tractatus Logico-Philosophicus, whose picture theory of meaning has it strictly as a function of propositional logic, and the later Wittgenstein of the posthumously published Philosophical Investigations, who famously proposed "meaning is use". More recent scholarship has tended to emphasize the continuity of Wittgenstein's thought, particularly with reference to his view of the essentially "therapeutic" nature of philosophy, and the implied ethics held to be consistent across his philosophical work. Wittgenstein kept extensive philosophical notes that have led to several posthumously published works, such as the Blue and Brown Books, Philosophical Grammar, Philosophical Remarks, and On Certainty.