Authoritarianism, Religiousness and Conservatism are among the most studied social attitudes in modern psychology . Measures of the three attitudes consistently correlate between 0.50 and 0.70. These strong correlations suggest that they form a higher order factor that I call Traditionalism. I review evidence that supports the idea of such a higher order factor distinct from other attitude factors and comparable higher order personality traits. I propose that an underlying cause of Traditionalism is the disposition to obey authority and more broadly to respond positively to symbols of authority. Contemporary research shows that variance in this trait is due to genetic factors and not due to patterns of childrearing. There is suggestive evidence that this trait facilitates reproductive fitness , but the evidence is very indirect and appropriately designed studies are needed to answer the question. The predisposition to obey authority is consistent with constructs in two other major evolutionary theories: Haidt’s theory of the evolution of moral intuition and Simon’s theory of “docility.” I further argue that while obedience to religious authorities can be seen as a form of exploitation, and may well be in some cases, the disposition to obey authority probably evolved in the context of reciprocity .