Sociobiologists often underestimate the distance between genes and culture. Previous works have argued that cultural traits often reduce rather than enhance the biological fitness of their participants and that individuals frequently make fitness-reducing decisions. This article adds the argument that interpreting culturally patterned behaviors as amplified inclusive fitness strategies requires specification of the individual-level behavior traits originally selected for, whose presence has permitted social interaction to generate, over historical time, the aspects of culture in question. Making explicit the psychological assumptions that a sociobiological interpretation of culture traits necessarily entails can produce important and testable hypotheses. Unfortunately those sociobiologists who keep their psychological assumptions implicit, and hence unexamined, unwittingly repeat many of the errors of the old culture-and-personality school.