“Never run when you're scared. Rule 7.”

“Never knowingly be serious. Rule 27.”

“The Doctor: This is bad, I don't like this. [kicks console and yells in pain] Never use force, you just embarrass yourself. Unless you're cross, in which case... always use force! Amy: Shall I run and get the manual? The Doctor: I threw it in a supernova. Amy: You threw the manual in a supernova? Why? The Doctor: Because I disagreed with it! Now stop talking to me when I'm cross!”

“You should always waste time when you don't have any. Time is not the boss of you. Rule 408.”

“Demons run when a good man goes to warNight will fall and drown the sunWhen a good man goes to warFriendship dies and true love liesNight will fall and the dark will riseWhen a good man goes to warDemons run, but count the costThe battle's won, but the child is lost”

“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]”