Austrian-born British philosopher, regarded by many as the greatest philosopher of the 20th century. Wittgenstein’s two major works, Logisch-philosophische Abhandlung (1921; Tractatus Logico-Philosophicus, 1922) and Philosophische Untersuchungen (published posthumously in 1953; Philosophical Investigations), have inspired a vast secondary literature and have done much to shape subsequent developments in philosophy, especially within the analytic tradition. His charismatic personality has, in addition, exerted a powerful fascination upon artists, playwrights, poets, novelists, musicians, and even filmmakers, so that his fame has spread far beyond the confines of academic life.