Madness is just what a genius looks like to a tiny mind.

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.

I know this is going to sound very self-serving, and I apologize for it, but if you can write comedy, you can pretty much write anything, because it's the hardest. It's the most technically demanding, the most precisely evaluated form of writing. People know if it works or not. There's a big button marked 'fail,' and that's when nobody laughs.

The Doctor: I've seen bigger. Clara: Really? The Doctor: Are you joking? It's massive!

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!

If it’s time to go, remember what you’re leaving. Remember the best.

When writing comedy, you have to have the confidence to believe that there is only one type of relationship in the world, and we are all having it, that all men behave in the same way and so do all women.