Proceedings of the Annual Meeting of the Cognitive Science Society

Complex reasoning, such as that elicited by GRE 'logical' reasoning problems, is demanding for human reasoners and beyond the competence of any existing computer program. We report four experiments carried out to investigate the question of what makes these problems difficult. The experiments established three causes of difficulty: the nature of the logical task (Experiment 1), the nature of the incorrect foils (Experiment 2), and the nature of the correct conclusions (Experiments 3 and 4).