It may seem indeed that our dreams are composed of the coarsest stuff of life, but that stuff is treated, kneaded so thoroughly, with a protraction due to the fact that none of the temporal limitations of the waking state is there to prevent it from spinning itself out to heights so vast that we fail to recognise it. On the mornings after this good fortune had befallen me, after the sponge of sleep had obliterated from my brain the signs of everyday occupations that are traced upon it as upon a blackboard, I was obliged to bring my memory back to life; by the exercise of our will we can recapture what the amnesia of sleep or of a stroke has made us forget, what gradually returns to us as our eyes open or our paralysis disappears.