John Maynard Keynes was the most influential economist, and one of the most influential thinkers, of the twentieth century. He overturned the orthodoxy that markets were optimally self-regulating, and instead argued for state intervention to ensure full employment and economic stability. This new selection is the first comprehensive single-volume edition of Keynes's writings on economics, philosophy, social theory and policy, including several pieces never before published. Full of irony and wit, they offer a dazzling introduction to a figure whose ideas still have urgent relevance today.