metaethics

Metaethics is the branch of ethics that investigates the nature, status, and meaning of moral judgments and moral language rather than prescribing specific actions. It asks what moral terms such as good, right, and ought mean, whether moral statements express beliefs about objective moral facts, emotions, or prescriptions, and whether moral truths exist at all.

Central issues include moral realism versus anti-realism (are there objective moral facts?), cognitivism versus non-cognitivism (do moral statements express truth-apt beliefs or attitudes and commands?), naturalism versus non-naturalism (are moral properties natural properties accessible to science, or non-natural and sui generis?), and positions such as constructivism and relativism. Prominent theories include moral realism (with naturalistic and non-naturalistic variants), emotivism and expressivism (moral talk expresses approvals or disapprovals rather than beliefs), prescriptivism (moral language functions as universalizable prescriptions), and error theory (all moral claims are false). The open question argument, advanced by G. E. Moore, challenges defining “good” in natural terms, while the is–ought distinction highlighted by David Hume cautions against deriving moral conclusions from factual premises.

Moral epistemology within metaethics explores how we know or justify moral beliefs, the roles of reason and moral psychology, and the prospects for moral knowledge or certainty. Metaethics is distinct from normative ethics, which asks what we ought to do, and from applied ethics, which considers concrete moral problems.