Leonard: Thank you for seeing me on such short notice.
Dr. Gallo: Ah, it's my pleasure. I'm curious, are you related to Dr. Beverly Hofstadter?
Leonard: Uh, she's my mother. You know her?
Dr. Gallo: No, not personally, but I have read all of her books.
Leonard: Well, then you know her better than I do.
Dr. Gallo: Well, I'm not so sure about that. But I can tell you I do not agree with her theories on child rearing at all.
Leonard: Really? Any chance you find them cold, cruel and unsuitable for innocent little boys who just want to be happy?
Dr. Gallo: Well, I didn't want to say it-
Leonard: No, no, say it. Sing it. Rent a plane, write it in the sky.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Sheldon: Perhaps I should explain. While working with Koothrappali, we discovered an asteroid, and I named it after you.
Amy: Oh, Sheldon, thank you. That's so romantic. But what about Rajesh? He was okay with you choosing the name?
Sheldon: Well, it took a little negotiating, but I wore him down. Uh, we get the asteroid, and if you and I have children, they all have to be named Rajesh.
Amy: All of them?
Sheldon: Even the girls.
Amy: Okay, I think I know what to say now.

Howard: You know, once we get the house back to ourselves, we can be romantic in any room we want.
Bernadette: Great. I can finally show you where the laundry room is.

Raj: Come on, a medium-sized asteroid is still an interesting discovery.
Sheldon: I suppose it could end up on a collision course with Earth and destroy life as we know it.
Raj: You dream different than me.