 As Cudd sees it, the most difficult and interesting question that an analysis of oppression must confront is the “endurance question: how does oppression endure over time in spite of humans’ rough natural equality?” (Cudd 2006, 25). Any satisfactory answer to this question must draw on a combination of empirical, social-scientific research and normative philosophical theorizing, inasmuch as a theory of oppression is an explanatory theory of a normative concept (Cudd 2006, 26). (That oppression is a normative – rather than a purely descriptive – concept is evident from the fact that it is defined as an unjust or unfair set of power relations). Cudd argues that social-theoretical frameworks such as functionalism, psychoanalysis, and evolutionary psychology are inadequate for theorizing oppression (Cudd 2006, 39–45). Structural rational choice theory, in her view, best meets reasonable criteria of explanatory adequacy and therefore provides the best social-theoretical framework for analyzing oppression. By appealing to a  structural  theory of rational choice, Cudd’s analysis of oppression avoids relying on assumptions about the psychology of individual agents. Rather, as Cudd puts it, “the structural theory of rational choice assesses the objective social rewards and penalties that are consequent on” the interactions and social status of specific group members and “uses these assessments to impute preferences and beliefs to individuals based purely on their social group memberships” (Cudd 2006, 45). But, as a structural theory of rational choice, the framework assumes “that agents behave rationally in the sense that they choose actions that maximize their (induced) expected utilities” (Cudd 2006, 46). In other words, structural rational choice theory models human actions as “(basically instrumentally rational) individual choice constrained within socially structured payoffs” (Cudd 2006, 37). When utilized to analyze oppression, structural rational choice theory suggests that the key to answering the endurance question lies in the fact that “the oppressed are co-opted through their own short-run rational choices to reinforce the long-run oppression of their social group” (Cudd 2006, 21–22).