The paper addresses the main issue of political theory: legitimacy. The theme is developed beginning with the basic concepts of the political philosophy of the Enlightenment: individualism, liberalism and philosophy of history, with the help of the conceptual historiography of Reinhart Koselleck, to point out a political aporia. The specific articulation between those concepts is then used to read the main works of Friedrich August von Hayek, as an example of the adaptation of that framework to neoliberalism and, on the other hand, to read the core of the work of Jürgen Habermas, as an example of the social-democratic version. The conclusion points to the systems theory of Niklas Luhmann as a possible alternative to the political aporia inherited from the basic conceptual framework of the Enlightenment.
Individualism and Liberalism; Philosophy of History; R. Koselleck; Neoliberalism and Social Democracy; A. Smith; F. Hayek; J. Habermas