Abstract

Questions regarding the nature of moral judgment loom large in moral philosophy. Perhaps the most basic of these questions asks how, exactly, moral judgments and moral rules are to be defined; what features distinguish them from other sorts of rules and judgments? A related question concerns the extent to which emotion and reason guide moral judgment. Are moral judgments made mainly on the basis of reason, or are they primarily the products of emotion? As an example of the former view, Kant held all moral requirements to be derived from a principle of rationality (the categorical imperative). As an example of the latter, Hume famously claimed that reason is “the slave of the passions” and that moral judgments stem from the moral emotions. When addressing these issues, philosophers have largely relied on the traditional tools of philosophical analysis, along with introspection, anecdotal evidence and armchair speculation. In recent years, however, a rich body experimental psychology has emerged which, in the view of a growing number of philosophers, casts important new light on these venerable questions. Our aim, in this chapter, is to illustrate how empirical methods can help move traditional philosophical debates forward in interesting and important ways. Since space does not permit an exhaustive survey of the relevant experimental work, we will focus on a few of the most compelling examples.