Which French philosopher is known for his ideas on social contract theory?

The French philosopher recognized for his contributions to social contract theory is Rousseau. His seminal work, "The Social Contract," published in 1762, posits that legitimate political authority derives from a social agreement among individuals. Rousseau argues that individuals must collectively agree to form a society and adhere to its rules, establishing a framework in which personal freedom is reconciled with social order. This concept profoundly influenced political thought, shaping ideas about democracy, citizenship, and human rights.

In contrast, Voltaire is primarily known for his advocacy of civil liberties and critique of organized religion, while Descartes is celebrated for his impact on philosophy and mathematics, particularly in rationalism. Hobbes, although also a key figure in social contract theory, is English and presented a more authoritarian view in his work, "Leviathan," where he argued for a strong centralized power to avoid chaos, differing significantly from Rousseau’s ideas of collective governance.