Horkheimer’s philosophy expresses in all its facets and new approaches that bourgeois society cannot be humane and free because its internal contradiction leads to a decay that appears as more or less continuous change. The internal contradiction manifests itself as an antagonism between the owners and non-owners of the means of production. As a competitive relationship among people in the state and as a competitive relationship among states, it continues and manifests itself in various forms of intellectual and cultural expressions. As an internal contradiction, it is to be reconstructed dialectically, that is, described as a historical-social event, in the course of which tendencies towards humanity and freedom only become reality by simultaneously realizing their own opposite. However, anyone who looks at university teaching and research today may get the impression that only the Dialectic of Enlightenment, co-authored with Adorno, is of interest from Horkheimer’s work. This may not least be due to certain dominant interpretations of Horkheimer’s complete works, which are presented in this chapter.