Amy: Then why I am here?
Doctor: Because, because I can't see it any more.
Amy: See what?
Doctor: I'm 907. After a while you just can't see it.
Amy: Seeing what?
Doctor: Everything. I look at a star. It is just a big ball of burning gas. I know how it began, how it ends and I was probably there both times. And after a while everything is just stuff. That's a problem. You make all the space and time your backyard and what do you have a backyard? But you, you can see it. And when you see it, I see it.
