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. (shrink)