When Beaumarchais let the major antagonist of his play The Barber of Seville voice his contempt of the siècle des lumières, he was not just introducing the character as an insufferable bigot, but also ironically characterizing the movement that he himself championed: the Enlightenment. For many European intellectuals, the Enlightenment heralded the loss of the stability and structure that were regained only a century earlier over the chaos of the reformation.1 This loss of structure not only became apparent in the realm of the political, where republicanism soon ran rampant through various social strata and classes, but also in the hallowed halls of epistemology and metaphysics. If the Enlightenment was the Age of Reason, it was so only in a very peculiar sense2 : all that the seventeenth century had recognized as rational – systematic structure, deductive order, unshakable foundation and certainty – was now disdained and scorned as oppression and hierarchy, barren tautology, superstition and a headstrong insensitivity to the one truly productive force in human reasoning: doubt. It was, then, the age of Reason’s self-deprecation and self-castigation.