The death of welfare economics : history of a controversy

The death of welfare economics has been declared several times. One of the reasons cited for these plural obituaries is that Kenneth Arrow's impossibility theorem, as set out in his path-breaking Social Choice and Individual Values in 1951, has shown that the social welfare function - one of the main concepts of the new welfare economics as defined by Abram Bergson (Burk) in 1938 and clarified by Paul Samuelson in the Foundations of Economic Analysis (1947, ch. VIII) - does not exist under reasonable conditions. Indeed, from the very start, Arrow kept asserting that his famous impossibility result has direct and devastating consequences for the Bergson-Samuelson Social Welfare Function (1948, 1950, 1951a, 1963), though he seemed to soften his position in the early eighties. On his side, especially from the seventies on, Samuelson remained active on this issue and continued to defend the concept he had devised with Bergson, tooth and nail, against Arrow's attacks (1967, 1977, 1981, 1987, 2005). The aim of this paper is precisely to examine this rather strange controversy, which is almost unknown in the scientific community, even though it lasted more than fifty years and saw a conflict between two economic giants, Arrow and Samuelson, and behind them two distinct communities - the fading welfare economics against the emerging social choice theory -, two conflicting ways of dealing with mathematical tools in welfare economics and, above all, two different conceptions of social welfare. By relying on different kinds of material, I attempt to grasp what the exchanges between Arrow, Samuelson and others, both overtly and behind the scenes, reveal regarding the motivations of my two main actors.