Abstract

The disagreement between Binmore and the “behaviouralists” concerns mainly the kind of reciprocity mechanisms that sustain cooperation in and out of the experimental laboratory. Although Binmore’s scepticism concerning Strong Reciprocity is justified, his case for Weak Reciprocity and the long-run convergence to Nash equilibria is unsupported by laboratory evidence. Part of the reason is that laboratory evidence alone cannot solve the reciprocity controversy, and researchers should pay more attention to field data. As an example, I briefly illustrate a historical case suggesting that the institutions that foster cooperation in the real world rely on Weak Reciprocity mechanisms such as those that feature prominently in Binmore’s story