We begin, with a short presentation of Cosmides’s social contract hypothesis, of Wason selection task, and of Cosmides’s reasons to use the task in order to test the theory. In a second section, we present the relevance-theoretic analysis of the selection task proposed by Sperber, Cara and Girotto (1995) which cast doubts on the appropriateness of the task to study reasoning. In a third section, we present Fiddick, Cosmides and Tooby’s (2000) defense of the use of the selection task as a tool to test evolutionary theories of reasoning, and argue that it is methodologically flawed. In a fourth section, we present three experiments designed to test contrasting predictions deriving from the two approaches. In the conclusion, we come back to Cosmides’s hypothesis and reflect on how it might be really tested…”