The study aimed to examine several assumptions of dual process theories of reasoning by employing individual difference approach. A set of categorical syllogisms was administered to a relatively large sample of participants (N = 247) along with attached confidence rating scales, and measures of intelligence and cognitive reflection. As expected, response accuracy on syllogistic reasoning tasks highly depended on task complexity and the status of belief-logic conflict, thus demonstrating beliefbias on the group level. Individual difference analyses showed that more biased subject also performed poorer on Raven's Matrices (r = .25) and Cognitive Reflection Test (r = .27), which is in line with assumptions that willingness to engage and capacities to carry out type 2 processes both contribute to understanding of rational thinking. Moreover, measures of cognitive decoupling were significantly correlated with the performance on conflict syllogisms (r = .20). Individual differences in sensitivity to conflict detection, on the other side, were not related to reasoning accuracy in general (r = .02). Yet, additional analyses showed that noteworthy correlation between these two can be observed for easier syllogistic reasoning tasks (r = .26). Such results indicate that boundary conditions of conflict detection should be viewed as a function of both tasks' and participants' characteristics.
