Because of the extent and evidence of political participation of intellectuals in France of the thirties, the latter may be considered as full actors of the political life and debates of these years. The historical circumstances are however not sufficient to explain the political role they then assumed. More precisely, the article is intended to show that in order to explain the peculiarity of the phenomenon, one must necessarily turn to the cultural data, i.e. the set of values and representations that found the social recognition of intellectuals in France and that account for the believe according to which those who, because of their intellectual activity, arenotorious, have an authorized opinion on political matters. In this perspective, one may conclude that the commitment of intellectuals in France of the thirties may not be reduced to a political fact. It also constitutes a cultural fact, resulting from the combination of a value crisis and the system of political attitudes attached, in this country, to the status of intellectuals.