Patterns of moral judgment derive from nonmoral psychological representations.

Ordinary people often make moral judgments that are consistent with philosophical principles and legal distinctions. For example, they judge killing as worse than letting die, and harm caused as a necessary means to a greater good as worse than harm caused as a side-effect (Cushman, Young, & Hauser, 2006). Are these patterns of judgment produced by mechanisms specific to the moral domain, or do they derive from other psychological domains? We show that the action/omission and means/side-effect distinctions affect nonmoral representations and provide evidence that their role in moral judgment is mediated by these nonmoral psychological representations. Specifically, the action/omission distinction affects moral judgment primarily via causal attribution, while the means/side-effect distinction affects moral judgment via intentional attribution. We suggest that many of the specific patterns evident in our moral judgments in fact derive from nonmoral psychological mechanisms, and especially from the processes of causal and intentional attribution.