The promise and perils of hybrid moral semantics for naturalistic moral realism

In recent years, several philosophers have recommended to moral realists that they adopt a hybrid cognitivist–expressivist moral semantics. Adopting a hybrid semantics enables the realist to account for the action-guiding character of moral discourse, and to account for the possibility of moral (dis)agreement between speakers whose moral sentences express different cognitive contents. I argue that realists should resist the temptation to embrace a hybrid moral semantics. In granting that moral judgments are partly constituted by conative attitudes, the realist concedes too much to her anti-realist opponents: she concedes that, at its most fundamental level, moral disagreement is disagreement in attitude, and the resolution of deep moral disagreement is best guided by non-epistemic norms of inquiry. Furthermore, on a hybrid semantics, moral thought and truth ascriptions turn out to be more responsive to the conative contents of moral judgments than to the supposed propositional contents. Finally, a hybrid semantics makes it difficult to preserve the realist’s claim that moral truths are in a certain sense independent of appraisers’ attitudes