Abstract

The paper defends the idea that strong reciprocity, although it accounts for the existence of deep cooperation among humans, has difficulty explaining why humans lived for most of their history in band-size groups and why the emergence of larger societies was accompanied by increased social differentiation and political centralization. The paper argues that the costs of incurring an altruistic punishment rise in large groups and that the emergence of large-scale societies depends on the creation of institutions that render control of these costs possible through a social division of sanction. Key Words: cooperation • strong reciprocity • cultural evolution • political evolution.