In this article, I reflect on the Warsaw school of the history of ideas (WSHI), a loose collective of people that formed after the birth of the communist system in Poland. First, I analyse the biographical factors that determined the political and intellectual choices of the WSHI members. Next, I attempt to show the nature of their public attitudes, which can be seen as part of the habitus of post-war Marxist intellectuals in Poland. My aim is to investigate how it happened that the WSHI, while was an element of Polish state at the beginning, became, in the 1960s, one of the primary points of contestation in Poland and an indicator of the collapse of the project of institutionalising Marxism-Leninism in Polish universities. I assume that the transformation did not entail a simple transmission from the nineteenth century to post-war revisionism but instead implied a series of breaks with, and migrations of, ideological models. Therefore, this analysis does not trace the line that separated the Polish leftist tradition from post-war communism, but rather describes their relationship, showing how the ethos of the socially engaged intelligentsia in Poland fitted into scholarly post-war biographies. My hypothesis is the following: in the case of the WSHI, the element of connection was a feature that Andrzej Mencwel refers to as “culturalism”—an ethical attitude inherited from earlier generations of leftist humanists.