This is a study on the creation process of the new mode of thinking Brazil and underdevelopment which is instituted by Florestan Fernandes (his problematics). The paper is specially concerned with the construction of the concept of dependent capitalism as a form of capitalism itself. It shows how Florestan Fernandes, since 1959-60, breaking away from the dominant ideology and departing from the conceptual pair autonomy/ heteronomy, characterizes the heteronomous situation: externally, as economic, social, political, ideological, and moral dependency; and internally, through the social class system, classes which support such dependence but which, under certain conditions, may as well oppose it. It also shows how Florestan Fernandes believes that the social revolution against the dependent capitalistic order is a condition for development.