Proceedings of the Annual Meeting of the Cognitive Science Society

In this paper we study selected argument forms involvingcounterfactuals and indicative conditionals under uncertainty.We selected argument forms to explore whether people withan Eastern cultural background reason differently about con-ditionals compared to Westerners, because of the differencesin the location of negations. In a 2 × 2 between-participantsdesign, 63 Japanese university students were allocated to fourgroups, crossing indicative conditionals and counterfactuals,and each presented in two random task orders. The datashow close agreement between the responses of Easterners andWesterners. The modal responses provide strong support forthe hypothesis that conditional probability is the best predic-tor for counterfactuals and indicative conditionals. Finally,the grand majority of the responses are probabilistically coher-ent, which endorses the psychological plausibility of choosingcoherence-based probability logic as a rationality frameworkfor psychological reasoning research.