Evidence for some form of abstract logical intuition.

Logical reasoning is often presumed to require effortful cognition. However, there is evidence that reasoners may have some form of "logical intuition" that generates rapid, intuitive logical responses to arguments. Previous studies have shown that intuitive logical judgments for some forms of inference can be generated by matching strategies or by activation of semantic information, leaving the existence of any form of purely logical intuition an open question. In this paper, we examined the possibility that once these effects are controlled for, at least some people are able to make rapid, intuitive logical inferences that reflect only logical structure. In two studies, participants were given 5 s to make a series of inferences, which included semi-abstract syllogisms of the form "All A are B, X is B, X is A," where the B term was abstract (meaningless), and for which both matching and semantic activation were controlled. Results show that about 15% of participants were able to consistently respond logically to these inferences. These indicate that there is a clear, although limited, form of abstract logical intuition.