Peter Hacker's Insight and Illusion is a thoroughly comprehensive examination of the evolution of Wittgenstein's thought from the Tractatus to his later 'mature' phase. This is a reprint of the revised and corrected 1989 edition, with a new foreword by Constantine Sandis. Hacker's book is now widely regarded as the best single volume study covering both the 'early' and the 'later' Wittgenstein. Until this third edition, the book had been out of print for 25 years.