Sheldon: (Playing hackey sack) One, two, three, four, five, six, seven, eight. Drat. I'm never going to get to forty-three again. One, two, three, four. Rats.

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.

Sheldon: You may not realize it, but I have difficulty navigating certain aspects of daily life. You know, understanding sarcasm, feigning interest in others, not talking about trains as much as I want. It's exhausting!

Leonard: It's hard sometimes. Everywhere you go, guys hit on you, even if I'm standing right there. And they're all taller than me. Why is everyone taller than me? You know what, this is all in my head. It's my problem, not yours.
Penny: Leonard, why do you always do this? Listen to me, you're the one I'm with. You know I love you. So will you please relax, because you're driving me crazy.
Leonard: You know that's the first time you ever said you love me.
Penny: Yeah.
Leonard: We're just supposed to pretend it's not a big deal?
Penny: That's exactly what we're gonna do, because you're about to make me cry. And we both know if I start crying, you're gonna start crying.
Leonard: You're right, I should go.

Penny: What am I supposed to say?
Leonard: Say "Can't talk right now, hanging with my boyfriend. England sucks. You suck. USA number one."