a1 University of Amsterdam and Erasmus University Rotterdam, The Netherlands.
Something happened to economics in the decade of the 1950s that is little appreciated by most economists and even by professional historians of economic thought. The subject went through an intellectual revolution as profound in its impact as the so-called Keynesian Revolution of pre-war years. I call it the Formalist Revolution after Ward (1972, pp. 40–41), who was the first to recognize the profound intellectual transformation of economics in the years after World War II.