A man brings up a Discovery Channel special he recently saw on astronomy. He says that he and his wife are sitting in bed watching it, and as a diagram of the solar system flashes onto the screen, his wife remarks that she didn't know the earth revolved around the sun. "How could you not know that?" he asks, incredulously. "Oh, shut up!" she snaps. "You don't know how to get to Neiman Marcus! Which do you think is going to be more useful?"