Sheldon: Is there some problem?
Leonard: Yeah. Listen, I have to kinda sneak out for a while.
Sheldon: All right, goodbye.
Leonard: No, wait. If anyone asks you where I went, you don't know.
Sheldon: Where are you going?
Leonard: I can't tell you that.
Sheldon: Who would ask me?
Leonard: I can't tell you that, either.
Sheldon: So you brought me in here to inform me that you can't tell me where you're going and you can't tell me who might ask?
Leonard: Yeah, I really didn't think this through.

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.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

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.

Sheldon: Scissors cuts paper, paper covers rock, rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitates lizard, lizard eats paper, paper disproves Spock, Spock vaporizes rock, and as it always has, rock crushes scissors.

Mrs. Wolowitz Tell her we're going to the Olive Garden. I have a coupon from the paper.
Howard: We're not going to the Olive Garden, ma!
Mrs. Wolowitz Oh, Mr. Big Shot with his Red Lobster.

Stephanie: So, how was your day?
Leonard: You know, I'm a physicist, I thought about stuff.
Stephanie: That's it?
Leonard: I wrote some of it down.