Swiss philosopher, specialised in philosophical psychology, philosophy of language and cultural philosophy. After a PhD on Husserl written in Leuven, he worked with Roman Jakobson at Harvard and Joseph Greenberg at Stanford. He was professor of philosophy at the Ruhr University in Bochum (1977-1990) and the ETH Zürich (1990-2002). He is known in particular for his interpretation of Jakobson's linguistics as a "phenomenological structuralism" and for his visual "Atlas of Philosophy".