Rousseau's explosive cry for human liberty helped to spark the French Revolution and has haunted our discussions of how we should rule one another ever since - seen as both a blue-print for political terror and as a fundamental statement of democracy.

Rousseau's explosive cry for human liberty helped to spark the French Revolution and has haunted our discussions of how we should rule one another ever since - seen as both a blue-print for political terror and as a fundamental statement of democracy.