Leda Cosmides
(University of California, Santa Barbara)
Cognitive adaptations for social exchange

Social exchange ? cooperation for mutual benefit ? is rare in the animal kingdom. Yet it is as characteristic of human beings as language and tool use. There are good reasons to think that the human cognitive architecture contains cognitive machinery that is specialized for reasoning about social exchange. I will present evidence ? cognitive, cross-cultural, and neuropsychological ? that our brains contain cognitive adaptations for reasoning about social exchange, which include a subroutine designed for detecting cheaters. Because social exchange allows trade, this evolved competence provides a cognitive foundation for human economic activity and other forms of cooperation. The results presented challenge the view that the mind is a blank slate, and cast new light on debates about human rationality.