Our discussion of the commentaries begins, at the evolutionary level, with issues raised by our account of the evolution of morality in terms of partner-choice mutualism. We then turn to the cognitive level and the characterization and workings of fairness. In a final section, we discuss the degree to which our fairness-based approach to morality extends to norms that are commonly considered moral even though they are distinct from fairness.

Social dilemmas, in which individually selfish behavior leads to collectively deficient outcomes, continue to be an important topic of research because of their ubiquity. The present research with Japanese participants replicates, with slight modifications, public goods games previously run in the United States. In contrast to recent work showing profound cross-cultural differences, the results of two studies reported here show remarkable cross-cultural similarities. Specifically, results suggest that (1) as in the U.S., allowing incremental commitment to a public good is effective (...) at eliciting contributions, (2) individual differences in trust affect contributions, (3) the distribution of player types in the U.S. and Japan are very similar, and (4) the dynamics of play in the public goods games used here are strikingly parallel. These results are discussed in the context of the relationship between cross-cultural differences and economic institutional environments. (shrink)