This is a history of economic thought from Adam Smith to John Maynard Keynes--but it is a history with a difference. Firstly, it is history of economic theory, not of economic doctrines. Secondly, it includes detailed Reader's Guides to nine of the major texts of economics in the effort to encourage students to become acquainted at first hand with the writings of all the great economists. This fifth edition adds new Reader's Guides to Walras' Elements of Pure Economics and Keynes' General Theory of Employment, Interest and Money as well as major additions to the chapters on marginal productivity theory, general equilibrium theory and welfare economics.