The Nth Doctor/Quotes

Third Doctor: Jo, it's all quite simple - I am he as he is me.
Jo Grant: (bemused) "And we are all together, coo coo cachoo?"

Third Doctor: What?

Jo Grant: It's a song by The Beatles.

Second Doctor: Oh, really? How does it go?

Third Doctor: Oh, please be quiet!

The Three Doctors

First Doctor: So you're my replacements...a dandy and a clown.

The Three Doctors (again)

Harriet Jones: Well, what happened to my Doctor? Or is it just a title that's passed on?

Tenth Doctor: I'm him. I'm literally him. Same man, new face. Well, new everything!

The Christmas Invasion