The logic sense: exploring the role of executive functioning in belief and logic-based judgments

Illusory intuitions: Challenging the claim of non-exclusivity

A person who arrives at correct solutions via false premises is right and wrong simultaneously. Similarly, a person who generates "logical intuitions" through superficial heuristics can likewise be right and wrong at the same time. However, heuristics aren't guaranteed to deliver the logical solution, so the claim that system 1 can routinely produce the alleged system 2 response is unfounded.

Illusory intuitive inferences: Matching heuristics explain logical intuitions

The capacity to evaluate logical arguments intuitively is a fundamental assumption of recent dual-process theories. One observation supporting this effect is the standard conflict effect on incongruent arguments under belief instruction. Conflict arguments are evaluated less accurately than non-conflict arguments, arguably because logic is intuitive and automatic enough to interfere with belief judgments. However, recent studies have challenged this interpretation by finding the same conflict effects when a matching heuristic cues the same response as logic, even on arguments with no logically valid structures. In this study, we test the matching heuristic hypothesis across 4 experiments (total N = 409) by manipulating the arguments propositions so that matching cues a response that is either (1) aligned or (2) misaligned with logic, or (3) cues no response at all. Consistent with the predictions of the matching heuristic, standard, reversed, and no conflict effects were found in those conditions, respectively. These results indicate that intuitively correct inferences which are assumed as evidence of logical intuitions are actually driven by a matching heuristic that cues responses aligned with logic. Alleged intuitive logic effects are reversed when the matching heuristic cues an opposing logical response or disappears when there are no matching cues. Therefore, it appears as though the operation of a matching heuristic, rather than an intuitive access to logic, drives logical intuitions.

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

Classic dual process theories of human reasoning attribute explicit reasoning to effortful, deliberative thinking. According to these models, intuitive processes lack any access to the formal rules of logic and probability and hence rely exclusively on superficial problem features to determine a response. However, in recent years, 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 four experiments, we instructed participants to judge the validity (Experiments 1 and 4), likeability (Experiments 1, 2, and 3), and physical brightness (Experiments 2, 3, and 4) of the conclusion to several reasoning problems. Brightness judgements were made by evaluating the font shade brightness of the argument's conclusion. Participants were also asked to complete a range of individual differences measures, drawing on cognitive ability and cognitive style, to evaluate the extent to which "logical intuitions" were linked to measures of deliberative reasoning. The results showed that participants judged the conclusion of logically valid statements to be more valid, more likable, and more physically bright than invalid statements. Participants with higher cognitive ability and unlimited processing time showed greater effects of logical validity in their liking judgements (varied across experiments). However, these effects were absent in the brightness tasks, suggesting that logic effects observed under instructions to judge conclusion brightness are a purer measure of "logical intuition." We discuss the implications of our findings for recent dual process theories of human reasoning.