The papers discusses the philosophically relevant issues in the work of M. Kusý during the normalization period in Slovakia (1969 – 1989). This period had two distinctive parts: the pre-Charter and Charter ones. The paper focuses on the latter: At that time M. Kusý was especially concerned with critical analysis of the ideology and practice of the so called “real socialism”, and revealing of the totalitarian nature of the communist regime. The author pays attention also to M. Kusý’s principled approach to the resolution of several other topics: Charter 77 and human rights, the position of an intellectual and civil courage, the problem of nationalism and the Slovak phenomenon, marxism and the ecological crisis, philosophy and social transformation etc. The author stresses the fact, that at that time M. Kusý´s views could be presented only in the underground an exile publications.