The short (and sometimes aphoristic) observations in Philosophical Investigations allow the reader to ponder basic questions on what describes a category, how language works in everyday situations, and how symbols function to represent our world.
Originally a series of notes to himself as he lectured on philosophy, the book is a brilliant grab bag of thought and example. Often framed as a question ("How do I recognize that this is red?"), the philosopher provides short answers in a sentence or two, never more than a paragraph. (The second part of the book uses longer answers of several pages to develop its arguments.) An index lets the reader browse on topics of interest--such as language, concept, games, or naming.
Any artificial intelligence researcher looking to understand human language will be intrigued by Wittgenstein's ideas on how symbols and language operate. And for anyone who designs software with objects, this book's careful attention to thinking about what makes a good category demonstrates rigorous thinking about everyday objects and things. Philosophical Investigations is at times a strange and often wonderful book that reveals the thought processes of one of history's finest minds. It exposes the fundamental problems of using language as a means of teaching machines to think using words. --Richard Dragan
Topics covered: Theory of language and language games, meaning and symbols, concepts and categories, behavior, games (including chess), color, images and perception, grammar and language, sensations, theory of mind and thinking.