Abstract

Karl-Otto Apel occupies a pre-eminent place among the German philosophers of the first post-war generation. His groundbreaking achievement, which has been unjustly overshadowed by the tenacious debate over the ‘ultimate justification’ of ethics, consisted in disclosing a new dimension in the philosophy of language and thereby completing the ‘linguistic turn’. He made the transition from formal semantics, which concentrates on the structure of propositions, to ‘transcendental’ pragmatics of language, which focuses on the formal aspects of the use and interpretation of linguistic expressions. In pursuing this path, he also laid the foundations for discourse ethics. The essay traces the stages of this ‘transformation of transcendental philosophy’ leading from the late Heidegger to Apel’s conception of ‘transcendental hermeneutics’ inspired by Peirce. Continuing the lifelong discourse with my friend Karl-Otto, I will conclude by addressing some problems raised by his justification of discourse ethics.