Wicked Company: Freethinkers and Friendship in Pre-Revolutionary Paris, By Philipp Blom

The fathers of the Revolution

Wicked Company is a group biography centred around the salon of a now little-known figure, Baron d'Holbach. It opens with a comic interlude, as Philipp Blom goes in search of the bones of the (other) great men of the European Enlightenment. Rousseau and Voltaire are interred in the Pantheon; Holbach and Denis Diderot, the Jesuit-turned-atheist philosopher and leader of the vast Encyclopédie project, lie in unmarked graves in a Paris church whose priest politely disavows all knowledge of them. "They have still not been forgiven for their unpalatably radical ideas," Blom observes, characterising those ideas in a lovely phrase: "A ... phantom ship in the history of philosophy."

Seemingly every radical intellectual in Europe was aboard. In a city full of salons, Holbach's was the toughest-minded, and the most male, though Blom also traces the lives of the women behind the philosophers: Holbach's two amiable wives, Diderot's long-term mistress, Sophie Volland, and the captivating and very intellectual Louise d'Epinay, among others. (Diderot's religious wife remained horrified by her husband's principles.)

Blom skilfully weaves his story around a large cast of characters, including Laurence Sterne, who influenced Diderot's sceptical novel Jacques le fataliste, David Hume, Adam Smith, the radical MP John Wilkes and Jean-Jacques Rousseau. The latter's embrace of the circle and final betrayal forms the emotional core of the narrative.

Blom teases out the nuances of the group's ideas with considerable finesse. Hardcore atheists they might have been, but he shows that they were no blind followers of reason. To the end of his life, Diderot continued his investigation into the human heart. He wanted life to be rich and full, moral and pleasurable, not a meaningless whirl of atoms. He wrote fiercely against slavery and colonialism and gave his beloved daughter a superlative education.

But Rousseau the apostate won the battle of ideas, thanks to good PR. His sensational Confessions presented him as a simple, natural man, whose touchstone was emotional truth. His accusations against his old friends were widely accepted rather than dismissed as the paranoid fantasies of an ingrate. The rationalists seemed like cold-hearted monsters next to passionate, self-righteous Jean-Jacques. Yet his totalitarian "Social Contract", as Blom shows, paved the way for Robespierre.

Holbach, Diderot and Rousseau died before the Revolution. There is one howler: the Marquis de Sade was not one of the prisoners freed from the Bastille when it fell on 14 July 1789. He had already been moved to a more secure jail for inciting the crowds with an improvised megaphone. Holbach and Diderot's wise, humanist voices were even more effectively silenced, and in a final indignity, their remains were violated and scattered by a Revolutionary mob.