Pierre Bayle

A Huguenot driven from France by religious persecution, Bayle settled in Rotterdam and wrote the Historical and Critical Dictionary, a sprawling work whose real arguments hide in the footnotes. There he set reason against faith, exposed contradictions in every system, and argued that morality does not depend on belief — that a society of atheists could be more virtuous than one of fanatics. His relentless doubt and his case for toleration made him, in Voltaire's phrase, the arsenal of the Enlightenment; the philosophes raided his pages for a generation. He doubted not to destroy but to clear the ground.