In reading Sophie's Choice
George Steiner says it so much better than I did:
One of the things I cannot grasp, though I have often written about them, trying to get them into some kind of bearable perspective, is the time relation...Precisely at the same hour in which [two Jews at the Treblinka extermination camp] Mehring and Langer were being done to death, the overwhelming plurality of human beings, two miles away on the Polish farms, five thousand miles away in New York, were sleeping or eating or going to a film or making love or worrying about the dentist. This is where my imagination balks.