In Part III we showed that discrimination makes a substantial and pervasive contribution to the unequal distribution of social resources and the subsequent establishment or maintenance of group-based hierarchy. However, there is another source of inequality besides discrimination. In this chapter we will argue that group-based social hierarchy is also maintained because people from dominant and subordinate groups actually behave differently. These behavioral differences are both a consequence of social hierarchy and a proximal cause of it.

Our analysis of group differences in behavior stems not from the assumption that there are basic or normal human proclivities that go awry in subordinate groups, or from the notion that people in dominant and subordinate groups have inherently different qualities or capacities. Rather, we argue that the behavioral differences between dominant and subordinate groups result from the fact that people within these groups live in profoundly different circumstances. Group-hierarchical societies are set up in ways that make life relatively easy for dominants and relatively difficult for subordinates. We saw clear evidence of this in Part III dealing with the “circle of oppression” and the pervasive group-based discrimination faced by subordinates. Less obvious, but still influential, are the ways that the most basic cultural, social, economic, and psychological tasks of life are made more difficult for subordinates and easier for dominants. These social conditions influence the psychological states and local social conditions of everyone in the society, causing, we argue, group differences in behavior, particularly in behavior that influences how well people do in life.