David Hume is, arguably, the most important philosopher ever to have written in English. Although best known for his contributions to epistemology, metaphysics, and the philosophy of religion, Hume also made substantial and influential contributions to psychology and the philosophy of mind, ethics, the philosophy of science, political and economic theory, political and social history, and, to a lesser extent, aesthetic and literary theory. All facets of Hume's output are discussed in this volume, the first genuinely comprehensive overview of his work. The picture that emerges is of a thinker who, though critical to the point of scepticism, was nonetheless able to build on that scepticism a profoundly important, and still viable, constructive philosophy.