Sheldon: Yeah, I have to say, it is nice to share this experience with someone who's on the same journey. Although right now ours is testing off the charts while yours is floating around in its own waste.
Bernadette: Are you actually comparing my human baby to your brain in a bowl?
Sheldon: Well, I didn't make you waddle up four flights of stairs for the heck of it.
Bernadette: You do realize my baby has functioning organs and can recognize voices.
Sheldon: Yeah, but ours can recognize a specific data stream among background noise.
Bernadette: Mine has a fully developed immune system.
Sheldon: Ours doesn't need an immune system because it lives in a state-of-the-art German incubator.

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: Still, I can't believe you can turn ordinary skin cells into functioning brain cells.
Amy: Well, I turned this one into a functioning boyfriend, so sky's the limit.

Raj: Well, I can't eat like a ten-year-old all the time.
Penny: You're dating somebody! Who is it?
Raj: What? What are you talking about?
Penny: You only watch what you eat when you're afraid you might have to take your shirt off.

Raj: Maybe there are other things we have in common. Come dinner-time, do you enjoy eating food?