On the Viability of Vengeance

by Daniel Friedman and Nirvikar Singh Economics Department UC Santa Cruz May 21, 1999 Abstract Using a simple symmetric game to illustrate, we point out shortcomings in previous theoretical accounts of how the human vengeance motive survives despite a free rider problem. We offer a new theoretical explanation involving the coevolution of genes that determine the capacity for vengeance and memes that regulate its expression. The main result, illustrated in a simple parametric example, is that coevolution in a fixed environment circumvents the free rider problem and that the prevailing vengeance level will efficiently serve groups of individuals.