  With the turn to language and reconstructive science, Habermas undermines both of the traditional Kantian roles for philosophy: philosophy as the sole judge in normative matters and as the methodological authority that assigns the various domains of inquiry to their proper questions. In Habermas's view, philosophy must engage in a fully cooperative relationship with the social sciences and the empirical disciplines in general. This step is completed in The Theory of Communicative Action, to which we now turn.