This thesis maintains that Jürgen Habermas‘s moral and political theories rely on a modified version of Kant‘s notion of normativity. Taking this as a starting point, it examines this component in light of criticisms inspired by Hegel‘s critique of Kant. The thesis shows that Habermas can answer most of the criticisms that could arise from Hegel‘s critique. That said, Hegel‘s criticism of the will as a tester of maxims does apply to Habermas. This criticism states that Kant cannot connect the universal will of morality and the particular will of the empirical subject because he rules out particular contents as susceptible of being universalized. And it can apply to Habermas because he set strict limits to what can count as a content which may bleed into the justification of moral norms and, following Kenneth Baynes – in his interpretation of Habermas‘s theory –, of legal and political norms. To be justifiable, – according to Habermas – these norms need to embody generalizable interests and they cannot be based on particular interests. However, Habermas infers from this that norms can only be justified with impartial, that is agent-neutral reasons, and cannot be justified with agent-relative reasons. From this, emerges the question whether and to what extent a theory of this sort can successfully include particular contents (for example a particular agents‘ real interests, inclinations and needs). The strict version of the generalizability of norms seems to occlude this possibility. Nonetheless, it is possible to rebut this criticism by slackening the strong version of normative justification that Habermas has built into the theory. By means of an analysis of two elements that he incorporates into his reconstruction of the normative point of view, namely, the concept of ideal role taking and the notion of mutual recognition, it is possible to argue that the loosening of the strict notion of generalizability is a modification that does not contradict and actually coheres with Habermas‘s Kantian concept of moral reason, and this operation fortifies the theory in the face of the Hegelian criticism of the will as a tester of maxims. To develop these issues, this work is divided in two parts with two chapters each part. Part I is an analysis of Habermas‘s notion of moral reason and autonomy and it reconstructs its normative Kantianism. After that, it discusses Hegelian criticisms of Habermas‘s moral theory. Part II focuses on Habermas‘s political Kantianism in Between Facts and Norms and in the debate with Rawls and it examines Hegelian criticisms of that Kantianism.

This thesis examines the “postsecular turn” taken by the philosophy of Jürgen Habermas since 2001, with a particular focus on his political theory. It argues that the postsecular turn was motivated primarily by the limitations of Habermas' philosophical paradigm of postmetaphysical thinking. It then analyses his model of postsecular deliberative democracy, and argues that the model should be rejected due to its reliance on an unworkable procedure of sacred-to-secular translation. The thesis is divided into three parts. Part 1 is an analysis of the place of religion in Habermas' writings on social theory from the 1970s and 1980s. It outlines his original account of religious language, and of the “linguistification of the sacred” which accompanies the transition from traditional to modern societies. Part 2 focuses on Habermas' paradigm of postmetaphysical thinking, and shows that the paradigm creates the conditions for postmetaphysical thinkers to appropriate religious concepts. It also argues that Habermas' inability to address the “anthropic problem” in postmetaphysical terms led to his turn to postsecularism. Part 3 examines the model of postsecular deliberative democracy which Habermas has argued for since 2001. Drawing on the accounts of religious language from Part 1 and of appropriation from Part 2, it concludes that the procedure of sacred-to-secular translation on which the model relies is unworkable.