The article explains the intellectual excursus of Jean-François Lyotard. In La condition postmoderne Lyotard addresses the problem of scientific knowledge and the problem of legitimacy of political practices. The author's aim is to demonstrate the existence of different "linguistic games" and consequently the impossibility for one of them to legitimise the others; hence the need to admit an incommensurable area, which is not covered by any language game. After 1979, with the growing interest for the Kant's Critic of Judgment, Lyotard found the possibility of communication between different linguistic games in the "reflexive judgment" and he identified the incommensurable with the sentiment of sublime. The an-aesthetic of sublime is at the origin of nihilism; nevertheless, at the same time, it is also the sentiment which can open a new way -versus the techno-scientific homologation of aesthetic experience -for a new pact that could revive in the sharing immediacy of the sentiment of beauty, immediacy which allows to grasp the sense of belonging to the same aesthetic experience. The transubjective sentiment is at the base of the community and of its origin, but in order to reach it, it is necessary to break the dominance of techno-science. From this point of view we can find Habermas having a nearer position to Lyotard; Habermas shows in his interest for the sentiment of life and love, present in Hegel's Spirit of Cristianism, his propensity towards the sentiment which is at the base of intersubjectivity forming the subject.