DOCTOR: Humans. I think you forget how powerful you are. Lives change worlds. People can save planets, or wreck them. That's the choice. Be the best of humanity.

KANE: You can't build an ionic membrane from scratch.

DOCTOR: If I had crayons and half a can of Spam, I could build you from scratch.

BELLA: You've got a plan, right?

DOCTOR: Oh, it's brewing. At least three-eighths of a plan right here... Two-eighths... I'll be honest, all I've got is the letter P, but sometimes that's all I need.

DOCTOR: Oh, come on. This is not the way to resolve a family dispute. How about good old-fashioned passive-aggressive discussion?