Unavailable for thirty years, this volume presents the original English / German edition of Wittgenstein’s Philosophical Investigations — one of the most influential philosophical works of the twentieth-century. The last product of intensive work by Wittgenstein during the period 1929-49, Philosophical Investigations explores the concept of meaning; of understanding; of propositions; of logic; of states of consciousness; and of many other topics. The fundamental ideas of the Tractatus are both expounded and criticized. This edition is the gold standard, preferred by students and scholars alike. Also recommended is “The Wittgenstein Reader” (Edited by Anthony Kenny; Blackwell Publishers, 1994, 0631-193626) — which is the only selection of the essential works of Wittgenstein ever published.