Logical Positivismalso called Logical Empiricisma philosophical doctrine formulated in Vienna in the 1920s, according to which scientific knowledge is the only kind of factual knowledge and all traditional metaphysical doctrines are to be rejected as meaningless. A brief treatment of Logical Positivism follows. For full treatment, see Positivism: Logical Positivism and Logical Empiricism.



In England, however, the direct influence of Wittgenstein proved much more powerful. Wittgenstein had visited England before World War I and had spent some time at Cambridge; while there he discussed logic with Bertrand Russell. The Tractatus Logico-Philosophicus expresses and generalizes the conclusions that he had reached upon philosophical questions. In 1929 Wittgenstein returned to Cambridge and worked there (with a few intermissions) until 1947. During this later period Wittgenstein himself subjected the doctrines of the Tractatus to fundamental criticism and produced what was in effect a new account of philosophy. His Philosophical Investigations (German text with English trans., 1953) appeared posthumously.