When you wake up from a half-dream, and you can’t remember a thing about it, so you begin to examine your brain, trying to think of all the things you could’ve been dreaming about: work, school, literature, past relationships, comic books, friends, seafaring, geography, sex, films, history, cats, death, and so on and so on—and not a single thing you think about reminds you of that half-dream. You find it impossible to conceive the idea that there are so many things in the world to think about, and yet it must be true because you’ve just exhausted your brain and still you cannot find the subject of that one elusive dream.