Present study is conceived as a contribution to the development of Czech humanistic Marxism and is devoted to the philosophers Karel Kosík, Robert Kalivoda and Ivan Sviták during the Czechoslovak spring of 1968. The author considers their philosophical positions, their social critique and their vision of a future democratic socialism as well as their distinctive political commitment inseparable from their philosophical development. For all three, those were long term concerns culminating in the political thaw of 1968. The study deals with their successive texts, written intentionally as contributions to a society-wide discussion or even as programmatic proclamations, showing the moments with which they contended at the time and what goals they followed. At the same time it points to quite evident difference between the thought of I. Sviták on the one hand and K. Kosík and R. Kalivoda on the other, while also attempting a more detailed sketch of differences in their views as well as of the agreements not evident at first glance.