Dr who forth doctor quotes The Invisible Enemy

The Doctor: Sometimes my brilliance astonishes even me.

Leela: Eugh, what's that?

The Doctor: That is why my brain is so much superior to yours!

The Doctor: What do you know about brains, anyway?

Leela: All right, all right, don't get excited!

The Doctor: I'll get excited if I want to! It's my brain! I'll tell you something about brains-- do you want to know something?

Leela: Not much.

The Doctor: I'll tell you anyway. Someone once tried to build a machine as efficient as the brain. The only problem was, it would have had to be bigger than London-- do you remember London?-- and powered by the entire European grid. And that was just a human brain. Mine's much more complex.

The Doctor: OW!

Leela: What did you do?

The Doctor: I think I told them my liver was disintegrating, I think.

The Doctor: Who are you?

The Nucleus: I am the Nucleus.

The Doctor: You're trespassing, you know. Treading on my unconscious, affecting my metabol... Nucleus of what?

The Nucleus: The Nucleus of the Swarm.

The Doctor: Oh. Oh, I see. Why did you choose my brain?

The Nucleus: Because of your intelligence.

The Doctor: Oh well, I can understand that, but you realise you have no right-

The Nucleus: I have every right! It is the right of every creature across the universe to survive, multiply and perpetuate its species. How else does the predator exist? We are all predators, Doctor. We kill, we devour to live! Survival is all, you agree?

The Doctor: Oh yes, I do, I do. And on your argument - I have the perfect right to dispose of you.

Leela: Don't worry, Doctor. I found the answer: knife them in the neck!

The Doctor: Hahahaha! That was a good idea of mine, K-9, to blow it up!

K-9: Affirmative!

Leela: What do you mean, it was a good idea of yours? It was my idea!

The Doctor: What was?

Leela: To blow it up!

The Doctor: Then you should be feeling very happy.