You can't just boss bacteria around like that," said the younger Mrs. Hempstock. "They don't like it." "Stuff and silliness," said the old lady. "You leave wigglers alone and they'll be carrying on like anything. Show them who's boss and they can't do enough for you. You've tasted my cheese.

There are some dogs which, when you meet them, remind you that, despite thousands of years of man-made evolution, every dog is still only two meals away from being a wolf. These dogs advance deliberately, purposefully, the wilderness made flesh, their teeth yellow, their breath a-stink, while in the distance their owners witter, "He's an old soppy really, just poke him if he's a nuisance," and in the green of their eyes the red campfires of the Pleistocene gleam and flicker.

You're always you, and that don't change, and you're always changing, and there's nothing you can do about it.

I love the auditioning process. I love working with the technical guys. I absolutely love the editing room. That was completely fascinating to me, working with an editor in crafting the thing into something you had in your head.

Idris: Are all people like this? The Doctor: Like what? Idris: So much bigger on the inside.

When the first living thing existed, I was there waiting. When the last living thing dies, my job will be finished. I'll put the chairs on the tables, turn out the lights and lock the universe behind me when I leave.

Each person who ever was or is or will be has a song. It isn't a song that anybody else wrote. It has its own melody, it has its own words. Very few people get to sing their song. Most of us fear that we cannot do it justice with our voices, or that our words are too foolish or too honest, or too odd. So people live their song instead.