German philosopher of language, born in Düsseldorf and Professor at the University of Frankfurt, has specialized in the history of the notion of language. Clear neokantiana training, has been proposed, in collaboration with J. Habermas, a "semiotic transformation of the kantismo". According to him, it is clear that the "a priori" that Kant had to depend on the possibility of knowledge and of the universality of science is not a deep structure of reason, but of the language. The language, says, can be operated by the "a priori" of the unlimited community (i.e., ideally open to all speakers) of the communication, which is justified by the fact that no one can use a language, and therefore make experience, if not well used certain rules of a language to a particular community of speakers. This unlimited communication community is often impeded by the social, economic and psychological circumstances, etc. The Elimination of these obstacles is delineated, according to him, as ethical task, which may concretize in the critique of ideology, in psychoanalysis, or the policy as such either.
Main works: Nicolás de Cusa language (1955), the idea of language in the tradition of humanism of Dante to Vico (1963), transformation of philosophy (two vols., 1973), the controversy between explanation and understanding (1979), think Habermas (1990), theory of truth and ethics of speech (1991).