Reinette: One may tolerate a world of demons for the sake of an angel.

Time travel is always more magical somehow when you go into the past. Traveling into the future is something you do, every day. You're just not going to get very far. So, I rather like the past travel.

All lives end. All hearts are broken. Caring is not an advantage.

Always take a banana to a party.

Rule 1: The Doctor lies.

The Doctor: [aiming gun at the ceiling] Didn't anyone ever tell you? There's one thing you never put in a trap if you're smart. If you value your continued existence, if you have any plans about seeing tomorrow, there's one thing you never, ever put in a trap. Angel Bob: And what would that be, sir? The Doctor: Me. [fires]

Don't play games with me! You just killed someone I like, that is not a safe place to stand! I'm the Doctor, and you're in the biggest library in the Universe. Look me up.