The evolution of economic thought can be traced back from its beginnings in classical antiquity up to the present day. In this book, Professor Alessandro Roncaglia offers a clear, concise and updated version of his award-winning The Wealth of Ideas, studying the development of economic thought through perspectives and debates on the economy and society over time. With chapters on prominent economic theorists, including William Petty, Karl Marx, and John Maynard Keynes, as well as on other important figures and key debates of each period, Roncaglia critically evaluates the foundations of the marginalist-neoclassical (scarcity-utility) approach in comparison to the Classical-Keynes approach. A comprehensive guide to the history of economic thought, this book will be of value not only to undergraduate and postgraduate students studying economic thought, but also to any readers desiring to study how economics has evolved up to the present day.