Leonard: Thought you were getting us dinner.
Penny: Sorry. I had to stop at Sheldon's and help him solve string theory.
Amy: What?
Penny: Yeah, turns out the answer's knots.
Leonard: That's cute, but you can't have knots in more than four dimensions.
Penny: Mmm ... you can if you consider them sheets. [chuckling] Good night.

Mary Cooper: Oh, Shelly. I have bad news. Mr. Watkins passed this morning.
Sheldon: Oh. Oh, I'm-I'm sorry.
Mary Cooper: I know. What are the odds of that?
Sheldon: Call you back.

Howard: Why would the military want Sheldon?
Leonard: I don't know. Target practice?

Bernadette: What about this?
Raj: Uh, okay. Uh, pull off the skirt, slap a lightning bolt on the front, and you got baby Flash. Ooh, stick a long sleeve under it. Boom, Baby Sheldon!

Penny: Is it possible that you're stressed because you're scared about getting married? I mean, it is a big change, and you're not good with little changes.
Sheldon: Well, that's nonsense. You name one little change I was upset with.
Penny: Uh, when they changed the green Skittle from lime to apple.
Sheldon: That is not the rainbow I grew up tasting.

Penny: No, I've been reading Bernadette's parenting book. It's like the answer key to the Sheldon test.

Sheldon: Neither of them will be the actual cake. I'm just using it as a bargaining chip to get Amy to agree to the whole wedding party getting rings and us getting one ring to rule them all.
Howard: I forget, which mental hospital are you guys registered at?

Howard: Look, I I can see you're upset, but I'm gonna need some ground rules. I mean, while we're apart, can I see other needy Indian men?

Sheldon: Sorry, but when you make a discovery like this, you don't just take it down to City Hall. You tell the whole world. And so I'll say it in Latin or Klingon or smoke signals, if that's not cultural appropriation.
Amy: It is.
Sheldon: Okay, so not smoke signals.

Sheldon: Amy, I usually know exactly what to say. But in this moment I have no words.
I guess I'm overwhelmed by you. In a good way. Not in the elevator in the Haunted Mansion way. Even if I can't tell you now how I feel, I will spend my life showing you how much I love you.

Barry Kripke: At wast, my wove has come awong, my wonewy days are over, and wife is wike a song, oh, yeah.

Leonard: Come on. You can build things. You were an astronaut.
Howard: That's true. You know, as a kid, I used to make model rockets. That'd be pretty cool to do with a son.
Sheldon: Model rockets. Finally, something interesting! What is your preferred mode of recovery?
Amy: Sheldon, we're helping our friends.
Sheldon: And we got to model rockets, yeah? It was a tedious road, but well worth the effort.
Amy: So, have you thought of any names?
Sheldon: Amy, we finally got to model rockets. Why are you turning back?

Penny: Leonard thinks when we broke up, it didn't bother me.
Zack: That's crazy. When we were going out, she used to talk about you all the time. In fact, I think she only dated me because I reminded her of you.
Leonard: Sure. Because we're both people?
Zack: Damn right we are.

Penny: I'm not leaving you for Bill Gates.
Leonard: You sure? I bet his Internet's really fast.

Sheldon: So with this level of high-power laser array, we would actually be able to solve the black hole information paradox once and for all.
President Siebert: That's impressive, and how much funding were you looking for?
Sheldon: $20 million.
President Siebert: Really? You think you can build that for $20 million?
Sheldon: Not a chance.
President Siebert: I'm sorry, then why are you asking me for it?
Sheldon: Because once you've spent $20 million, you're much more likely to give me an additional 50.
President Siebert: So actually, what you're saying is with $70 million, you can build this.
Sheldon: I can see why you'd think that, but no. You can't go to the board of trustees and say you gave Sheldon Cooper $70 million and have nothing to show for it. No, the only way you'd be able to save face is to double down.
President Siebert: So 140?
Sheldon: And then double again.
President Siebert: 280?
Sheldon: And then - good news - not quite double again. So, uh, what do you say? We have a deal?