A statue isn't built from the ground up -- it's chiseled out of a block of marble -- and I often wonder if we aren't likewise shaped by the qualities we lack, outlined by the empty space where the marble used to be. I'll be sitting on a train. I'll be lying awake in bed. I'll be watching a movie; I'll be laughing. And then, all of a sudden, I'll be struck with the paralyzing truth: It's not what we do that makes us who are. It's what we don't do that defines us.