Alternative examples stored in memory are fundamental for the correct interpretation of the conditional proposition "If P, then Q". This paper proposes that associative strength and set size of semantic categories have a critical role in activation of alternative models. Also, the more the number of alternative models generated as a function of inference type, the greater the difficulty of the task due to information overload in working memory. Experiment 1 confirmed significant effects of associative strength, category set size, type of inference and interaction effects. Experiment 2 showed that the effects of associative strength are context-dependent determined by the reduction of semantic field. These findings are consistent with the hypothesis that knowledge stored in memory plays an important role in conditional reasoning.
conditional reasoning; mental models; associative strength; category set size