The bright homunculus in our head: individual differences in intuitive sensitivity to logical validity

Classical dual process theories of human reasoning attribute explicit reasoning to effortful, deliberative thinking. Lacking any access to the formal rules of logic and probability, according to these models, intuitive processes rely exclusively on superficial features of the problem. In recent years, however, researchers have demonstrated that reasoners are able to solve simple logical or probabilistic problems relatively automatically, a capability which has been called logical intuition. In two experiments, we examined the existence of this capability by instructing participants to rate their judgment of likeability (Experiment 1) and brightness (Experiment 2) of several reasoning problems. In order to investigate individual differences in these measures of logical intuition, participants were also asked to complete two scales of cognitive ability and cognitive style. The results showed that participants rated the conclusion to logically valid statements more likable and more physically bright. Although participants with higher cognitive ability showed greater logical intuition in their liking judgment, this effect, however, was absent when the brightness task, as another measure of logical intuition, was used. We discuss the implications of our findings for recent dual process theories of human reasoning.