Herrade Igersheim, 2015-16 HOPE Center Fellow

Two economists disagreeing about something is hardly news—unless they happen to be two of the most famous economists of the twentieth century who kept up a running debate with each other for no less than half a century.

As Herrade Igersheim explains, the two economists, Paul Samuelson and Kenneth Arrow, could not agree about the so-called social welfare function, which ranks the priorities that a society has as a whole.

Samuelson maintained that such a function existed; Arrow did not.

“I want to understand just what was behind the controversy, and why it was so important to Samuelson and Arrow,” Herrade says.

For Herrade, who is on the faculty at the University of Strasbourg, Duke University is the ideal place to pursue her questions: both Samuelson’s and Arrow’s papers are housed in the David M. Rubenstein Rare Book and Manuscript Library, as part of the Economists’ Papers Project.

“The papers, and especially the correspondence, has cast a whole new light on the subject. I came here thinking that the disagreement between Samuelson and Arrow was a matter of technical conditions and particular axioms. But the unpublished records help us to understand that what was at stake were two different and conflicting styles of reasoning, and thus they allow us to go beyond the formal aspects of the controversy."

As Herrade explains, Samuelson represented what, by the early 1950s, had become a fading tradition of welfare economics, the branch of economics that considers how a society should arrange its economic activities and allocate its resources. Arrow, in contrast, was a leader in the emerging social choice theory, which deals with collective decision-making or the process by which individual preferences can—or cannot—be aggregated to represent collective preferences.

“The debate between Samuelson and Arrow is surprisingly little known in the scientific community, probably because on the surface it was so technical. But as the archives show, there was a lot going on under the surface.”

This is Herrade’s first visit to Duke. She became interested in applying for a HOPE Center fellowship after hearing about former fellow Michael Assous’s time here. Michael was a fellow in 2012–13.

Herrade and her family have been living in Chapel Hill. “But we really live in a forest. There are deer in our garden morning and evening. That’s a far cry from our usual life in the middle of Strasbourg.”

She says that Chapel Hill has been a perfect community for her family. “The neighbors have been great, inviting us for potlucks and to Halloween parties and even a Super Bowl party.”

Herrade and her family will return to Strasbourg this summer.

--Paul Dudenhefer