RICHARD ARENA is Professor of Economics at the University of Nice-Sophia-Antipolis. He was one of the founders of the European Society for the History of Economic Thought. He has edited several books on the history of economic thought, including studies of Keynes, Sraffa and Schumpeter. - MICHEL QUERE is Research Professor in Economics at the French National Centre for Scientific Research (CNRS-IDEFI). His research interests include the history of economic thought, theory of the firm and the economics of innovation. He has written several works on the economics of Alfred Marshall.