Wittgenstein's first published work. Should be as famous for Russell's misunderstanding of it, made obvious in his introduction, as for it's effect on the positivists and modern philosophical logic. Absolutely essential reading for studying Wittgenstein's later work. The Investigations can be read as a refutation of the Tractatus, and thereby, as a refutation of much of contemporary philosophy of language. While Wittgenstein doesn't help his readers with either references or explanatory preamble, the effort of reading this book will be well rewarded to anybody studying contemporary issues in philosophical logic, philosophy of language or philosophy of science. Whatismore, Wittgenstein's poetic style is a joy to read and many of his aphorisms will come back to you in other studies.