Hahn, Frank Horace – A German economist (Berlin, 1925 - Cambridge, 2013), with British nationality, professor of economics at the University of Cambridge since 1972, from 1992 Emeritus professor. He has taught also at Birmingham University (1948-60) and at the London School of Economics (1967-72). He was Chief Editor of the Review of Economic Studies (1965-68) and President of the Royal Economic Society (1986-89). From 1990 until 1996 he was professor at the University of Siena, where he coordinated the doctorate program; in Italy he then established his main residence. He has proposed a penetrating interpretation of the problems emerging in the theory of general equilibrium. In particular, he studied problems related to the existence and stability of the equilibrium, as well as within the Non-Walrasian economics framework of imperfect competition. These findings provided the basis for a lively critique to monetarism. Some of his main works have been: General Competitive Analysis (with K. Arrow, 1971); On the Notion of Equilibrium in Economics (1973); Money and Inflation (1982); Money, Growth, and Stability (1985). In 1995 he published (with R. M. Solow) A Critical Essay on Modern Macroeconomic Theory, were he introduced a new macroeconomic model to explain the fluctuations in the labour market, the relation between wages and employment and the role of monetary policy.