Abstract

People usually fail the Wason selection task, choosing P and Q cases, when attempting to validate descriptive rules having the form “If P, then Q.” Yet they solve it, selecting P and not-Q cases, when validating deontic rules of the form “If P, then must Q.” The field of evolutionary psychology has overwhelmingly interpreted deontic versions of the selection task in terms of a naturally-selected, domain-specific social-contract or cheating algorithm. This work has done much to promote evolutionary psychology as an alternative to a mindblind sociobiology that ignores the computational structure of cognitive mechanisms in producing people's behaviors. Nevertheless, evolution-minded researchers outside cognitive psychology know little of the ample literature challenging this interpretation and uncritically cite the “cheater-detection module” as a key insight into human cognition. Although a priori arguments for a specially evolved cheater-detection module are plausible, the selection task provides no direct evidence for such a module.