This work examines what it means to be a philosopher and attacks the sterility of modern philosophy. Philosophy, the authors insist, is not contemplation, reflection or communication, but the creation of concepts. Part One explores the nature and scope of philosophy and its relation to social and economic development. It explores the concept, the plane of immanence in which it can be born and the conceptual personae which activate it. It concludes with an account of philsophy's relation to social and economic development, from ancient Greece to the modern capitalist state. Part Two sets out to illuminate the distinctiveness of philosophy by considering other forms of thought: science, art, literature and music.