Of all the critiques of the Enlightenment, the most telling may be found in the life and writings of Jean-Jacques Rousseau. This searching, long overlooked auto critique receives its first full treatment by Mark Hulliung. Here he restores Rousseau to his historical context, the world of the philosophes, and shows how he employed the arsenal of Voltaire, Diderot, and others to launch a powerful attack on their version of the Enlightenment. With great intellectual skill and rhetorical force, Rousseau exposed the inconsistencies and shortcomings of the Enlightenment: the psychology of Locke, the genre of philosophical and conjectural history, the latest applications of science to the study of society and politics, and the growing interest in materialist modes of thought. As the century moved on, Hulliung shows, the most advanced philosophes found themselves drawn to conclusions that paralleled Rousseau's-an agreement that went unacknowledged at the time. The Enlightenment that emerges here is richer, more nuanced, and more self-critical than the one reflected in many interpretations.By extracting Rousseau from personal entangle-ments that stymied debate in his time and that mislead critics to this day, Hulliung reveals the remarkable-and remarkably unacknowledged-force of Rousseau's accomplishment. This edition includes a brilliant new introduction by the author.