Sheldon: What are you listening to?
Amy: Nothing.
Sheldon: Oh, come on, I want to hear.
Sheldon: (on a recording) We don't need GPS. Let's just see where the road takes us.
Sheldon: I see why you turned it off. That guy sounds like an idiot.
Penny: Honey, that's you.
Sheldon: Don't be silly. My voice is deep and sonorous. Like a Caucasian James Earl Jones. "Luke, I am your father." See?

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.

Bernadette: One of the great things about being pregnant is drinking cranberry juice out of a wineglass and watching people freak out.

Penny: Is it possible that you're stressed because you're scared about getting married? I mean, it is a big change, and you're not good with little changes.
Sheldon: Well, that's nonsense. You name one little change I was upset with.
Penny: Uh, when they changed the green Skittle from lime to apple.
Sheldon: That is not the rainbow I grew up tasting.

Howard: It's a date. Just pick one.
Sheldon: It's not just a date, it's a textbook optimization problem. There is a perfect date. Just like there's a perfect room temperature and a perfect dessert.
Penny: Mm. There's no perfect dessert.
Sheldon: Yellow cake in the shape of a dinosaur with chocolate frosting, a scoop of vanilla ice cream on the side, not touching. You'll see. You'll have it at our wedding.
Amy: You wanna bet?