Voltaire, as a young man, had spent time in England. There, he had seen for himself how faith, in the transformative potency of enlightenment, from aristocratic salons to the meeting halls of Quakers, had resulted in what appeared to him an enviable degree of tolerance. ‘If there were only one religion in England, there would be danger of tyranny; if there were two, they would cut each other’s throats; but there are thirty, and they live happily together in peace.’