Raj: For God's sake, just drive in the knife, why don't you!
Stuart: What's your problem?
Raj: Well, you're all thinking that I'm the only one who hasn't done anything worthwhile.
Sheldon: I was not thinking it. Although, now that you point it out, it is undeniable.

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.

Amy: What is this?
Sheldon: A functional MRI of my brain. I did Sudoku before they took it so I'd be ripped.
Amy: I love it. Thank you.
Sheldon: And it's not just an MRI. The orbitofrontal cortex is lit up because I was thinking of you.

Penny: Howard and Bernadette's kid might be born on your birthday. How cool is that?
Amy: Yeah, but I thought this baby was supposed to ruin their sex life, not mine.

Raj: Don't come to the hospital. We're headed home.
Penny: Oh, that was fast. Did she sneeze the baby out?