Samuelson's social welfare function and Buchanan's critique: the struggle with normative science

A history of the transformation of public finance into public economics necessarily involves an understanding of the tension between positive and normative statements, that is a history of how public economists dealt with Robbins's requirements that economists should not make normative statements. In this paper, we propose to contribute to this history by discussing and comparing the works of two major economists of the 20th century, Paul Samuelson and James Buchanan. We show that they both use the same strategy to deal with the positive/normative tension: they adopt a reduced scale of analysis to escape normative judgements - the family for Samuelson and small groups (clubs) for Buchanan. What they do manage at this level is to create examples or models which remove that normative response from the theorist, and ascribe it to the participants. The normative views of the theorist are not involved. Yet, when one shifts back to a larger scale, the positive element of the analysis is less clear, at least in Samuelson's work.