A User's Guide to Thought and Meaning is Jackendoff's most important book since his groundbreaking Foundations of Language. Written with an informality that belies the originality of its insights, it presents a radical new account of the relation between language, meaning, rationality, perception, consciousness, and thought, and, extraordinarily, does this in terms a non-specialist will grasp with ease. Jackendoff starts out by looking at languages and what the meanings of words and sentences actually do.