In the opening lines of his Eighteenth Brumaire of Louis Bonaparte, Karl Marx writes: The tradition of all the dead generations weighs like a nightmare on the brain of the living. And just when they seem engaged in revolutionizing themselves and things, in creating something that has never yet existed, precisely in such periods of revolutionary crisis they anxiously conjure up the spirits of the past to their service and borrow from them names, battle cries, and costumes on order to present the new scene of world history in this time-honored disguise and this borrowed language.