George Berkeley (1685-1753) is, with John Locke and David Hume, one of the three major figures in the British empiricist school of philosophy. He has been the centre of much attention recently and his philosophical profile has gradually changed. In the 20th century he was almost exclusively known for his denial of the existence of matter (as this term was defined in those days), but today it is no longer reasonable to confine an account of Berkeley to the challenging philosophical inventions that he published when he was a young fellow at Trinity College in Dublin. This is a welcome trend. It shows Berkeley as a contributor not only to epistemology, metaphysics and moral and social philosophy, but also to a wide range of subjects including mathematics, philosophy of science, empirical psychology, political economy and monetary policy. The present collection aims at meeting this new trend by presenting a broad and comprehensive picture of Berkeley's works in their historical context. The contributors are some of the finest international experts in the field. The editors hope that this collection will show George Berkeley as he was: a wide-ranging, widely influential and courageous philosophical innovator. This volume has been published to celebrate the 300th anniversary of George Berkeley's Principles.