Nice Strategies in a World of Relative Gains

Abstract

The debate between neoliberals and realists in the field of international relations draws heavily on the findings offered in Robert Axelrod's Evolution of Cooperation. Axelrod's well-known argument is that cooperation can emerge among egoists despite the absence of a central authority. This article assesses the robustness of Axelrod's findings in light of the realist critique that relative gains concerns make cooperation less likely than neoliberals contend. We build on an amended prisoner's dilemma (PD) game and conduct a computer simulation tournament in which we vary (1) the payoff structure and (2) Axelrod's population of strategies. The results indicate that cooperation can emerge even under strong relative gains concerns, so long as the population of strategies is sufficiently retaliatory. On the basis of this finding, we argue that the realist critique is overstated: the introduction of greater relative gains concerns does not necessarily limit the prospects for cooperation among states.