This book examines Keynes's philosophical thinking as it developed from his earliest works through to The General Theory. It explains the role of philosophy in Keynes's later economics, showing how development and change in Keynes's philosophical thinking affected the development of his later economic thinking. The book represents a case study in the philosophy of economics, and unlike other books on the topic of Keynes and philosophy, argues that Keynes changed his philosophical views as he came to think about economics.