Dispositional measures of actively open-minded thinking and cognitive reflection both predict reasoning accuracy on conflict problems. Here we investigated their relative impact on meta-reasoning. To this end, we measured reasoning accuracy and two indices of meta-reasoning performance – conflict detection sensitivity and meta-reasoning discrimination – using a ratio-bias task. Our key predictors were actively open-minded thinking and cognitive reflection, and numeracy, cognitive ability, and mindware instantiation were controlled for. Actively open-minded thinking was a better predictor of reasoning accuracy and meta-reasoning (...) discrimination than cognitive reflection, and was the only dispositional measure to significantly predict conflict detection sensitivity. Thus, susceptibility to biased reasoning and meta-reasoning may be better captured by a reasoner’s ability to engage in open-minded thinking than by their ability to engage in reflective thinking. (shrink)