Abstract

Difference in performance in Wason selection tasks between descriptive and deontic sentences - or specific subclasses of deontic sentences - has been interpreted by some scholars as an experimental evidence of the domain-specificity of human reasoning and of the mind's massive modularity hypotheses. An alternative explanation of this difference is that the two tasks are incomparable because they are structurally different and therefore require different cognitive processes. In a between-subject study we presented four selection tasks with analogous structure that differed only for the rule content (descriptive, deontic, social contract and precaution). Results showed no difference between the experimental conditions and suggest that the difference between descriptive and deontic tasks, found in other studies, was due to the type of reasoning required by the experimental instructions rather than to the specific content of the conditional sentences.