Penny: So it's fine with you if I'm not smart.
Leonard: Absolutely. [Penny closes the door on him] Okay, this time I know where I went wrong

Leonard: [Sheldon] says he's moving out.
Raj: What did you do? Did you change the contrast or brightness settings on the television?
Leonard: No.
Raj: Did you take a Band-Aid off in front of him?
Leonard: No.
Wolowitz: Did you buy generic ketchup? Forget to rinse the sink? Talk to him through the bathroom door?

Penny: Has [Leonard] ever been involved with someone who wasn't a brainiac?
Sheldon: Oh, well, a few years ago, he did go out with someone who had a Ph.D. in French Literature.
Penny: How is that not a brainiac?
Sheldon: Well, for one thing, she was French. For another, it was literature

Howard. You do not have a PhD. Your cologne is an assault on the senses, and you're not available for video games during the Jewish high holidays

Sheldon [on weighing which friends to keep]

What part of an inverse tangent approaching an asymptote don't you understand?

Sheldon

A fear of heights is illogical. A fear of falling, on the other hand, is prudent and evolutionary

Sheldon

Sheldon [looking at the women's book in a bookstore]: "Coping with the Death of a Loved One." My condolences
Woman: Thank you
Sheldon: Family or friend?
Woman: Family
Sheldon: Too bad. If it had been a friend, I'm available to fill the void

Penny [referring to Sheldon]: What's up with Ichabod?
Leonard: Oh, he's trying to make a new friend
Penny: Well good for him
Leonard: Unless he makes one out of wood like Geppetto, I don't think it's going to happen

Don't get the wrong idea; the way I see it, I'm halfway to pity sex

Wolowitz

We're all pathetic and creepy and can't get girls, that's why we fight robots

Kripke

Sheldon [to Kripke]: Also, I am given to understand that your mother is overweight.
Raj: Oh, snap.
Sheldon: Now of course, if that is the result of a glandular condition and not sloth and gluttony then I withdraw that comment.

How is "doable" anything but a compliment?

Wolowitz

The Big Bang Theory Season 2 Quotes

Sheldon [to Kripke]: Also, I am given to understand that your mother is overweight.
Raj: Oh, snap.
Sheldon: Now of course, if that is the result of a glandular condition and not sloth and gluttony then I withdraw that comment.

How is "doable" anything but a compliment?

Wolowitz