Hume is one of the greatest of all British philosophers, and even in his own lifetime was celebrated as one of the pivotal figures of the Enlightenment. A central theme of his philosophy is the conviction that questions traditionally thought of as completely independent of the scientific realmDSquestions about the mind, about morality, and about God, for exampleDSare actually best explained using the experimental methods characteristic of the natural sciences. Hume's 'naturalist' approach to a wide variety of philosophical topics resulted in highly original theories about perception, self-identity, causation, morality, politics, and religion, all of which are discussed in this stimulating introduction by A J Ayer, himself one of the twentieth century's most important philosophers. Ayer also gives an account of Hume's fascinating life and character, and includes generous quotations from Hume's lucid and often witty writings.