Raj: I came here for your support.
Leonard: Well, then, you just walked up three flights of stairs for nothing.
Penny: Wait, don't you mean four flights?
Leonard: No, it's actually three.
Penny: But we're on the fourth floor. I mean, you have the lobby, first floor, second, third, fourth.
Leonard: The lobby's the first floor, so lobby, second, third, fourth.
Penny: That does not seem right.

Howard: Hey, have you checked the dates on these? They're all expired.
Stuart: You buy candy in a comic book store, you get what you get.

Amy: Okay, imagine you're looking in a mirror. The image you see looks just like you. That's called symmetrical.
Sheldon: Now imagine you have a billion mirrors, and each of them reflects one thing about you correctly and a billion things about you incorrectly. And imagine the set of incorrect things are floating in an abstract n-dimensional hyperspace. Now imagine there was never a mirror to begin with.

Bernadette: My dad and I watched you win back-to-back championships.
Kareem Abdul-Jabbar: And I watched you sniff Joe's hair when he wasn't looking.

Bert: I don't really have dreams, when I sleep or in life.

Amy: Really, Sheldon? You want to do it again?
Sheldon: Don't act surprised. It's clearly marked on the schedule. Now, shall we steam the wrinkles out of our wizard robes, or make vigorous, socially sanctioned love? Either way, I can check something off my to-do list.
Amy: [reading Sheldon's to-do list on his phone] Socially sanc-- Oh, wow. Yeah, there it is right there.

Sheldon: You know, spending time with Michael and Halley today really made me think about our future children.
Amy: Huh, what an interesting and completely unforeseen development.

Sheldon: Yes. And a reminder, Penny, there's free alcohol in business class, don't abuse it.
Penny: Relax. I'm not gonna drink.
Bernadette: Why? You pregnant?
Penny: Wha-? [laughs] No. No, I just, you know, I don't like to drink when I fly.
Bernadette: Please. I've seen you drink in the shower.
Howard: You guys have showered together?
Bernadette: Sometimes you're just ech.

Leonard: Don't make it sound childish. It's the scientific word for dust.
Penny: What was wrong with "dust"?

Howard: All right, got his enemies list. Ooh, he updated the interface. You can search by first name, last name or length of grudge.
Raj: Is Tam on it?
Howard: Let's see. Yep. Right here. Tam Nguyen.
Leonard: Oh, great. What did he do?
Howard: Hold on. I have to agree to the terms of service. No, I'm not a robot. Okay.
"Which of these are plants?" And we're in.

Mrs. Fowler: I can't believe it. All this time I've been angry at you when I should have been angry at Amy.
Sheldon: Look at that. We're both angry at Amy. Maybe that's something we could bond over. Let me ask you this: how do you feel about Howard?
Mrs. Fowler: Oh, is he that odd little friend you have with the haircut?
Sheldon: I may have married the wrong Fowler.

Sheldon: It's so funny, we did all these experiments on them and they didn't even notice.
Amy: I know, I was worried it would be obvious, but it wasn't.

Penny: So when was the last time you saw Howard in his astronaut uniform?
Bernadette: About a week ago.
Penny: Really? What was the occasion?
Bernadette: Date night. We do a little role-playing.
Penny: What role do you play?
Bernadette: (Russian accent) I am Ykatarina Nazdorovya, lonely Russian cosmonaut who is expert at physics and making love.
Penny: Okay, that just made the next hour really weird.

Raj: Wait, wait, so you don't know what their fight was about?
Georgie: I wish I could help you, boys. But, you know, Sheldon used to keep an enemies list when he was a kid.
Leonard: Oh, he still does.
Georgie: Really? I figured that went the same way as his bathroom schedule.
Howard: If you mean digitized, annotated and put online, it did.
Georgie: Maybe that'll tell you something. Hey, while you're looking at it, if I'm still on there for peeing in his shampoo bottle - Eh, you know what, just leave it.

Leonard: Okay, what would you do?
President Siebert: I'd find some sap and put him in charge so I wouldn't have to be the bad guy.
Leonard: That's a really good id-- Oh.