" The neurons that do expire are the ones that made imitation possible. When you are capable of skillful imitation, the sweep of choices before you is too large; but when your brain loses its spare capacity, and along with it some agility, some joy in winging it, and the ambition to do things that don't suit it, then you finally have to settle down to do well the few things that your brain really can do well--the rest no longer seems pressing and distracting, because it is now permanently out of reach. The feeling that you are stupider than you were is what finally interests you in the really complex subjects of life: in change, in experience, in the ways other people have adjusted to disappointment and narrowed ability. You realize that you are no prodigy, your shoulders relax, and you begin to look around you, seeing local color unrivaled by blue glows of algebra and abstraction. "

― Nicholson Baker , The Mezzanine