Rousseau's 1762 treatise opens with one of the most famous sentences in political philosophy: Man is born free, and everywhere he is in chains. What followed was a theory of legitimate government based on the general will, the collective decision of the people to live under laws they have chosen together. The book influenced the French Revolution, Kant, and virtually all subsequent political thought. Rousseau did not invent democracy, but he gave it a philosophical foundation that still structures our debates about freedom and obligation.