Amy: Well, it sounds like a nice night. We should go.
Sheldon: Wine again? Yeah, no, thank you. I like my grapes the old-fashioned way, in a juice box.

Raj: I don't like bugs, okay. They freak me out.
Sheldon: Interesting. You're afraid of insects and women. Ladybugs must render you catatonic.

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.

Sheldon: Why are you crying?
Penny: Because I'm stupid.
Sheldon: That's no reason to cry. One cries because one is sad. For example, I cry because others are stupid, and that makes me sad.

Leonard: Hey, did you ever think about the military applications for the guidance system?
Sheldon: Of course.
Leonard: Does it bother you?
Sheldon: No, it did at first. But then I talked it through with Frank and Alicia, and they really helped put things into perspective.
Leonard: Who are these people?
Sheldon: Leonard, friends are like toilet paper. It's good to have extras under the sink.

Zack: I see what you're saying. She's not so great.
Raj: Don't listen to him. He says crazy things all the time. Uh, watch. Marco.
Zack: Polo.

Raj: Yeah, okay, just do me a favor and stop talking about how great Claire is.
Zack: Anything for you, my little foreign friend.