Choi and Nisbett (2000) reported that Koreans showed stronger hindsight bias than Americans. The purpose of this study was to see whether hindsight bias is stronger among Easterners than among Westerners using a probability judgment task, and to test an eexplicit-implicitf hypothesis and a erule-dialecticsf hypothesis. We predict that the implicit process is more active among Easterners to generate hindsight bias, and that Easterners are more dialectical thinkers, whereas Westerners are more rule-based thinkers. French, British, Japanese, and Korean participants were asked to make probabilistic judgments in a scenario including conditional probabilistic judgment (Experiment 1) and in a Good Samaritan scenario (Experiment 2). In the results, Easterners showed greater hindsight bias generally, and their cognition was more implicit and dialectic.