Abstract: Liberty and dictatorship are two respects of the French Revolution，the political culture of which was branded with radicalism. But there is also a school of moderate French political thinkers，including Montesquieu，Benjamin Constant，Mme de Stal and Tocqueville，who tried to seek a balance point among various radical tendencies，and whose common point was to emphasis the social dimension while discussing the political issues.As for Montesquieu，he divided the state nature into three different types according to the social pattern in different historical stages，and his discussion of the relationship between the nature and the principle underlined the interactive mode between the politic and the society. As an heir to Montesquieu’s discussion on the differences between the ancient social pattern and the modern one，Benjamin Constant clarified the difference between “the Liberty of Ancients” and “the Liberty of Moderns”，the connotation of which should be discussed in a Republic built in a great country，and the fundamental principle of which is Popular Sovereignty. Mme de Stal，soul mate of Constant，investigated on how to construct a republican system，with which people can realize the Liberty of Moderns，and which she named “the Dictatorship of Institutions”，the aim of which was to satisfy the circumstantial demands，and at the same time to influence the mores consciously，and to erect a solid social infrastructure for the consolidation of republican system. However，far from entering into the stability，the French Republic failed into depotism again and again due to the fragile social infrastructure.With regards to Tocqueville，who no longer confined himself to influencing the mores with the aid of state construction，approached the topic directly from the respective of mores，and tried to explore how to improve the democratic society，and how French Republic could get rid of the despotism.

Key words: politicsociety , liberty , dictatorship , French Revolution