Karl-Otto Apel
Authors: Mendieta Eduardo 
Published: January 2021

Karl-Otto Apel (b. 1922–d. 2017) was one of the most original, influential, and renowned German philosophers of the post–World War II generation. He is credited with what is known as the linguistification of Kantian transcendental philosophy, in general, and the linguistic transformation of philosophy in Germany, in particular. His name is closely associated with that of Jürgen Habermas, his junior colleague, whom he met as a graduate student in Bonn in the 1950s, and with whom he maintained a lengthy philosophical collaboration. He received his doctorate in 1950 with a dissertation titled Dasein und Erkennen: Eine erkenntnistheoretische Interpretation der Philosophie Martin Heideggers (translated as: “Dasein and knowledge: An epistemological interpretation of Martin Heidegger’s philosophy”). However, as early as the 1950s, Apel had become increasingly critical of the relativistic and historicist consequences of his phenomenological and hermeneutical work. In 1962, he presented his Habilitation at the University of Mainz, which was published in 1963 as Die Idee der Sprache in der Tradition des Humanismus von Dante bis Vico (translated as: “The idea of language in the traditions of humanism from Dante to Vico”). This book is a pioneering reconstruction of the Italian philosophy of language and how it laid the foundations for the different currents of the philosophy of language that would branch out in the modern philosophies of language. In 1965, Apel published “Die Entfaltung der ‘sprachanalytischen’ Philosophie und das Problem der ‘Geisteswissenchaften,’” which was translated into English as Analytic Philosophy of Language and the “Geisteswissenschaften” in 1967. This was the first work of Apel to be translated into English, but it is also emblematic of Apel’s pioneering engagement with “analytic” philosophy. In 1973, at the urging of Habermas, Apel published Transformation der Philosophie (Transformation of philosophy) in two volumes. A selection, mostly from the second volume, appeared in 1983 under the title Towards a Transformation of Philosophy. In this work Apel introduced the idea that would become the hallmark of his thinking: The Apriori of the Community of Communication, by which he meant that the conditions of possibility of all knowledge and interaction are already given in every natural language that belongs to a community of speakers, who are per force already entangled in normative relations, that can never be circumvented or negated lest one commit a performative self-contradiction. In 1975, Apel published Der Denkweg von Charles S. Peirce: Eine Einführung in den amerikanischen Pragmatismus (The intellectual path of Charles S. Peirce: An introduction to American pragmatism), which is made up of the lengthy introduction he had written for his two-volume German selection and translation of Peirce’s writings. His next most important book was Diskurs und Verantwortung: Das Problem des Übergangs zur postkonventionellen Moral (translated as: “Discourse and responsibility: The problem of the transition to a postconventional morality”), from 1988, a collection of essays in which Apel develops his own version of discourse ethics. Apel’s last three books are collections of essays: Auseinandersetzungen in Erprobung des transzendentalpragmatischen Ansatzes (1998) [Confrontations: Testing the transcendental-pragmatic proposal) (It should be noted that Auseinandersetzungen, one of Apel’s favorite words, could also be translated as “coming to terms” with a particular thinker. This is an important volume as in three extensive essays Apel discusses his differences with and departures from Habermas’s version of universal pragamatics.); Paradigmen der Ersten Philosophie: Zur reflexiven–transzendentalpragmatischen Rekonstruktion der Philosophiegeschichte (2011) (translated as: “Paradigms of first philosophy: Toward a reflexive-transcendental-pragmatic reconstruction of the history of philosophy”), and Transzendentale Reflexion und Geschichte (2017) (translated as: Transcendental reflection and history”).