In the aftermath of the Paris atrocities, intellectuals have turned to enlightenment thinkers to refute religious orthodoxy. “I kept thinking of Voltaire,” writes scholar Robert Darnton in an essay for NYRB, “And calling up his famous grin — lips curled and lower jaw stuck out, as if to defy anyone who might dare to pull a punch.” That impish, thin-lipped smile is now on view at the Château de Versailles. In response to the attacks, the palace has rehung a portrait of the revolutionary 18th-century French writer in a central hall, the New York Times reports. “What is Tolerance?” reads a nearby quote by the philosopher in French and English. “It is the consequence of humanity.”