Making Psychology Normatively Significant

The debate between proponents and opponents of a role for empirical psychology in ethical theory seems to be deadlocked. This paper aims to clarify the terms of that debate, and to defend a principled middle position. I argue against extreme views, which see empirical psychology either as irrelevant to, or as wholly displacing, reflective moral inquiry. Instead, I argue that moral theorists of all stripes are committed to a certain conception of moral thought-as aimed at abstracting away from individual inclinations and toward interpersonal norms-and that this conception tells against both extremes. Since we cannot always know introspectively whether our particular moral judgments achieve this interpersonal standard, we must seek the sort of self-knowledge offered by empirical psychology. Yet reflective assessment of this new information remains a matter of substantive normative theorizing, rather than an immediate consequence of empirical findings themselves.