The Social Contract by Jean-Jacques Rousseau (1762)

"Man is born free, and everywhere he is in chains." Rousseau opens with the sentence that would help topple a monarchy, then spends the rest of the book asking the question buried inside it: not how to break the chains, but how to make them just. His answer is the general will, the idea that a people can author the laws they live under and so obey only themselves, that authority drawn from the consent of the governed is the one authority that does not enslave. It is a thrilling, dangerous, impossibly hopeful proposition, that a crowd of strangers might become a single body politic and govern itself without a master. Read it knowing the Bastille fell within Rousseau's century and the men who stormed it carried his sentences in their heads. Few books have argued, this fiercely, that freedom and obedience could be the same act.