"[I]t is impossible, through reading alone, to interpret the past. Nor is emotion enough. The historian must have a third quality as well: some conception of how men who are not historians behave. Otherwise he will move in a world of the dead. He can only gain that conception through personal experience, and he can only use his personal experiences when he is a genius. In Gibbon, as in no other English historian, this tenuous circle was complete. He was a genius who read, dreamed, and also knew — knew, by direct contact, a fragment of the rough stuff of society, and extended his knowledge through the ages."