HABERMAS, JÜRGEN (1929-) German social philosopher best known for his work on the project of Enlightenment and communicative theory in the public sphere. Habermas is perhaps the best known of the so-called second-generation Frankfurt School critical theorists. He was a student and assistant of Theodor Adorno and signi cant in uences on his early work and thought, which was more concerned with sociology rather than philosophy, included Karl Marx and Max Weber. However, from the 1960s his work has become more concerned with philosophical issues. His most important texts include Knowledge and Human Interests (1968), The Theory of Communicative Action (1981) and The Philosophical Discourse of Modernity (1987).