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

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

Penny: Yes, I will go out with you.
Leonard: Really?
Penny: Yeah. Why not? I mean, what do I have to lose?
Leonard: Yeah. That's the spirit

Penny: Leonard isn't the kind of guy I usually go out with.
Sheldon: Leonard isn't the kind of guy anyone usually goes out with

Leonard: What happened?
Penny: Well, I went over to Mike's to make up with him.
Leonard: Yeah. No, I know that part.
Penny: But he had already moved on.
Leonard: Already? That was quick.
Penny [crying]: That's what I said to the woman who had her legs wrapped around his neck!

Penny: I swear to God, I am done with guys like that. You know, macho with the perfect body and hair, and money.
Leonard: Yeah, that must get old quick

Penny: I was just wondering if I could talk to you. It's about Leonard.
Sheldon: Why me? Why not Koothrappali or Wolowitz?
Penny: Well, Raj can't talk to me unless he is drunk, and Wolowitz is, you know, disgusting

Penny: Maybe we should talk first.
Leonard: Okay, but before you say anything, have you ever heard of Schrödinger's cat?
Penny: Actually, I've heard far too much about Schrödinger's cat.
Leonard: Good.
[Leonard kisses Penny]
Penny: Alright, the cat's alive. Let's go to dinner

Sheldon: Leonard made it very clear, he doesn't want a party.
Wolowitz: Did someone say party?
Penny: He just doesn't know he wants one because he never had one.
Wolowitz: I suppose that's possible, but for the record I've never had a threesome and yet I still know I want one.
Penny: Howard here's a difference: the possibility exists that Leonard could have a birthday party before hell freezes over.
Wolowitz: Fine, if I do have a threesome you can't be part of it... I'm just kidding. Yes, you can. Can you bring a friend?

Penny: Well, Sheldon you are his friend. Friends give each other presents.
Sheldon: I accept your premise; I reject your conclusion.
Wolowitz [whispers]: Try telling him it's a non-optional social convention.
Penny: What?
Wolowitz: Just do it.
Penny: It's a non-optional social convention.
Sheldon: Ahh, fair enough.
Wolowitz: He came with a manual

Leonard: I don't celebrate my birthday.
Penny: Shut up. Yeah, you do.
Leonard: It's no big deal. It's just the way I was raised. My parents focused on celebrating achievements and being expelled from a birth canal was not considered one of them

Leonard: How did you know my birthday's Saturday?
Penny: I did your horoscope, remember? I was going to do everybody's until Sheldon went on one of his typical psychotic rants.
Sheldon: For the record, that psychotic rant was a concise summation of the research of Bertram Forer, who, in 1948, proved conclusively through meticulously designed experiments that astrology is nothing but pseudoscientific hokum.
Penny: Blah, blah, a typical Taurus

TBBT Quotes

Penny: Here's a question-- as an alien pretending to be human, are you planning to engage in any post-prom mating rituals with Amy?
Sheldon: There are post-prom mating rituals?
Penny: Not always. Unless your date drives a van with an air mattress, then always.
Sheldon: Well, if it's part of the prom experience, then I'm open to it.
Penny: You're kidding.
Sheldon: I may be an alien, but I have urges.If Amy wants to copulate by firing her eggs into space, well, then, I will happily catch them with the reproductive sac on my upper flermin. I'm not the best at reading facial cues, but I can see that you're a little turned on.

Sheldon: If you could wake up tomorrow having gained any one quality or ability, what would it be?
Penny: Well, not to steal from the Bible, but turning water into wine sounds pretty good.