In this paper we study selected argument forms involving counterfactuals and
indicative conditionals under uncertainty. We selected argument forms to
explore whether people with an Eastern cultural background reason differently
about conditionals compared to Westerners, because of the differences in the
location of negations. In a 2x2 between-participants design, 63 Japanese
university students were allocated to four groups, crossing indicative
conditionals and counterfactuals, and each presented in two random task orders.
The data show close agreement between the responses of Easterners and
Westerners. The modal responses provide strong support for the hypothesis that
conditional probability is the best predictor for counterfactuals and
indicative conditionals. Finally, the grand majority of the responses are
probabilistically coherent, which endorses the psychological plausibility of
choosing coherence-based probability logic as a rationality framework for
psychological reasoning research
