This study "Philosophie im Konjunktiv. Nichtidentität als Ort der Möglichkeit des Utopischen in der negativen Dialektik Theodor W. Adornos" (Subjunctive Philosophy. Nonidentity as the Place for the Possibility of the Utopian in the Negative Dialectics of Theodor W. Adorno) deals with Adorno’s utopian thinking and asks on what it depends and on what it is founded. Moreover, the study asks the question wherein the possibility of fundamental societal change can be found and on what it can be founded. This study develops an answer to these questions through the analysis of the concepts of the nonidentity and the nonidentical – central concepts in Negative Dialectics –, which in the theory of Adorno constitute a place at which thinking and human beings are not fully absorbed by and integrated in philosophical and scientific systems or in the structure of society. Within the nonidentical the subsuming identities of philosophy and society are broken up. Therefore, the possibility of the utopian appears in this break of the identical. Here, the emancipation of the nonidentical could be realized: an emancipation, however, which is made possible in the nonidentical. The utopian thinking and the possibility of the utopian on the one hand, and nonidentity and the nonidentical on the other hand, are – this is the main claim of the study – inseparable. In developing this answer the study also tries to solve a certain problem in the discussion of Adorno’s philosophy, namely the difficulty in connecting the critical dimensions of his thinking - which are dominating his work and directed against the tradition of philosophy (and science) and capitalist society - with its utopian motives, through which he is calling for change in different ways. Finally, it is argued that Adornos’s thinking, which attempts to realize the utopian and to transcend reality on the basis of nonidentity, must be understood as a subjunctive philosophy.