The article aims to throw light on the place of social contract theory in the legitimation theories of political power. More specifically, it aims to highlight the place of the Rousseau's theory among important contractualist theories during the Hobbbesian and the Lockeian period. This place is characterized by the definition proposed by Isaiah Berlin. In his article, he positions Rousseau with the partisans of positive liberty, while Locke and Hobbes are given precedence in negative liberty. After comparing and commenting on the critical formulations of the contracts by all three philosophers, which are in line with Berlin's position, the article ends up mentioning the concepts of civic education, civic religion, and the lawgiver as inherent threats to the coherence of Rousseau's social contract theory and to the priority of its inherent right before duty. PUBLICATION ABSTRACT