Jürgen Habermas’ discourse theory of morality should be understood, in metaethical terms, as a constructivist theory. All constructivist theories face a Euthyphro-like dilemma arising from how they classify the constraints on their metaethical construction procedures: are they moral or non-moral? Many varieties of Kantian constructivism, such as Christine Korsgaard’s, classify the constraints as moral, albeit constitutive of human reason and agency in general. However, this constitutivist strategy is vulnerable to David Enoch’s ‘shmagency’ objection. The discourse theory of morality, by classifying the constraints on the metaethical construction procedure (principles (D) and (U)) as non-moral, can avoid this problem.
