Dissatisfied with earlier attempts by Gottlob Frege and Bertrand Russell, Ludwig Wittgenstein (1889-1951) attempted to elucidate the nature of logical truth in his Tractatus Logico-Philosophicus (1922). Wittgenstein was concerned with the relation between language and the world and the logical and mathematical ramifications of this relation (Blackburn 390, Bunnin and Yu 739). In the Tractatus, Wittgenstein asserted that in order to describe reality, logic is necessary, but not sufficient and, in so doing, put forth what has come to be known as the picture theory of meaning (Rohmann 430). In his picture theory of meaning, Wittgenstein argued that language mirrors reality. Whether the picture theory of meaning collapses with Wittgenstein’s rejection of the metaphysics of logical atomism of the Tractatus is disputed among philosophers, but there is a consensus that Wittgenstein abandoned the theory in his later philosophy (Bunnin and Yu 531).
Wittgenstein’s exposition of his later philosophy appears in his posthumously published Philosophical Investigations (1953.) In the Philsophical Investigations, Wittgenstein turns his attention from the subject matter of the Tractatus to the workings of ordinary language, the philosophy of psychology and the philosophy of mathematics. The later Wittgenstein rejects his earlier unified theory of meaning in favor of an explanation based on a diversity of “language games” governed by rules and constituting a form of life. His later approach did not insist on an account of meaning as a psychological or abstract entity, but instead focused on the use of words and sentences (Bunnin and Yu 738-739).