The systematic study of the physical world had its orgins in philosophy; two-and-a-half millennia later, the scientific advances of the twentieth century are bringing the two fields closer together again. In this brilliant new textbook, Lawrence Sklar gives a broad overview of contemporary philosophy of physics which readers at all levels, especially students, should find accessible and engaging. Professor Sklar provides a clear and accurate guide to the key topics: the nature of space and time, the problems of probability and irreversibility in statistical mechanics, and, of course, the many notorious problems raised by quantum mechanics. He discusses sophisticated scientific questions, but avoids the use of technical formalism, so that the discussion will be accessible to those without a training in philosophy or physics.