Discourse Ethics beyond Apel and Habermas. A Realistic Relaunch

Karl-Otto Apel, not Jürgen Habermas (as is often wrongly supposed) is the philosophical originator of discourse ethics (“Diskursethik”).The central contention of a discourse ethics, according to Apel’s lectures in the mid-sixties, is that some necessary presuppositions of discourse have universally valid moral content, or at least some content that is morally relevant, i.e. relevant for outlining a morality the principles of which have unassailable rational credentials. If any such presuppositions can be identified as governing the practice of rational argumentation, then for any interlocutor’s communicative intention in a debate, waiving such presuppositions will clash with the construal of that debate as rationally meaningful debate, since it involves the interlocutor in a kind of inconsistency that Apel (like Habermas), drawing on speech-act theory, conceptualizes as a “performative self-contradiction”.