In this study, we explored cultural differences in subjective well-being and decision-making. Firstly, we examined the Japanese conceptions of happiness and risk by means of a word association task and a questionnaire, and discussed the dialectical nature of happiness in East Asia compared with Euro-American cultures. Secondly, we conducted a cross-cultural survey and found that scores on life satisfaction, self-esteem, maximization, and regret in the Japanese sample are significantly lower than in 12 other countries. Thirdly, we conducted a survey in Japan and found that the negative relationship between critical thinking attitude and life satisfaction was mediated partially by assessment tendency, maximization, and regret. On the other hand, the positive relationship between critical thinking attitude and life-satisfaction is mediated by locomotion tendency. Finally, we discussed the effect of wisdom on critical thinking and practical intelligence in solving problems in life, referring to our Japanese survey data.