What's wrong with my humor? It's funny... Rose laughed, so did Martha and Donna... What's wrong with it?
[The Doctor laughs at the comment] I'm a baby? You're me, you know. I'm you. We're the same. And who knows, you ended up here, didn't you? We some how always managed to end up somewhere exciting.
[When the other moves to poke him in the chest, the Doctor tries to jump back but he's too slow. He stares, bewildered] How did you... You could have just killed us both! You could have just destroyed the whole universe! It's bad enough we're in the same time line, but you touched me! [He blinks a few times before pulling out his glasses, popping them on, and poking the other one back] Oh, well that's not fair. Rose touched herself as a baby and nearly wiped out the entire human race.