Part 1 of this paper discusses some uses of arguments from radical moral disagreement—in particular, as directed against absolutist cognitivism—and surveys some semantic issues thus made salient. It may be argued that parties to such a disagreement cannot be using the relevant moral claims with exactly the same absolutist cognitive content. That challenges the absolutist element of absolutist cognitivism, which, combined with the intractable nature of radical moral disagreement, in turn challenges the viability of a purely cognitivist account of moral judgments. Such a conclusion could be staved off if it could be held that a sufficient condition for commonality of cognitive content in moral judgments could consist, despite the presence of radical moral disagreement, in the parties’ acceptance of a common set of fundamental moral principles. Part 1 begins, and Part 2 further develops, a destructive critique of that idea, leading thereby to a skeptical appraisal of the important role sometimes assigned, in metaethical theorizing, to moral rules. Inter alia the paper is intended to suggest the possibility of overlap between relativist and particularist agendas.