Sheldon: I feel renewed. I'm ready to deal with any changes that come my way. [sees Penny] Your hair is different. You changed your hair. I can't take this. I'm out.

Sheldon: Who's ready to laugh? [Leonard groans] Okay. So Feynman, Einstein and Schrodinger walk into a bar. Feynman says, "It appears we're inside a joke." Einstein replies, "But only to an observer who saw us walk in simultaneously." To which Schrodinger says, "If someone's looking in the window, I'm leaving."
Leonard: [chuckles] That's actually funny.
Raj: You should send that to Jimmy Fallon.

Mary Cooper: Thank you, God, for the food we are about to receive and for the nourishment of our bodies and bless the hands that prepared it. Amen.
Sheldon: Given that your hands prepared it, isn't that a little self-serving?
Mary Cooper: You start changing the words to the prayers, next thing you know, you're in a church with a guitar.

Sheldon: What is the best number? By the way, there's only one correct answer.
Raj: 5,318,008?
Sheldon: Wrong. The best number is 73. [short silence] You're probably wondering why.
Leonard & Howard: No, no, we're good.
Sheldon: 73 is the 21st prime number, its mirror 37 is the 12th and its mirror 21 is the product of multiplying, hang on to your hats, 7 and 3. Did I lie?
Leonard: We get it. 73 is the Chuck Norris of numbers.
Sheldon: Chuck Norris wishes. In binary, 73 is a palindrome, 1001001, which backwards is 1001001, exactly the same. All Chuck Norris gets you backwards is Sirron Kcuhc.
Raj: Just for the record, when you enter 5,318,008 in a calculator, upside down it spells boobies.

Amy: Do you need anything else?
Sheldon: You know exactly what I need.
Amy: Fine. [sings and plays autoharp] Soft kitty, warm kitty, little ball of fur. Happy kitty, sleepy kitty, purr, purr, purr.
Sheldon: That's nice. Now in German.
Amy: [sings and plays autoharp] Weiches Kätzchen, warmes Kätzchen, das nie und nimmer murrt. Liebes Kätzchen, müdes Kätzchen, schnurrt, schnurrt, schnurrt.
Sheldon: Great. Now Mandarin.
Amy: [sings and plays autoharp] Ruǎnmiánmián de xiǎo māomī máoróngrōng, kuàilè kēshuì qīngqiǎo māomī, gūlǔ gūlǔ gūlǔ.
Sheldon: Now Navajo.

Leonard: Penny. We are made of particles that have existed since the moment the universe began. I like to think those atoms traveled fourteen billion years through time and space to create us, so that we could be together and make each other whole.

Sheldon: Professor, can you identify our cricket?
Crawley: Of course I can. I can identify every insect and arachnid on the planet. Not that that's gonna keep me from having to move in with my daughter in Oxnard. And we're not talking Oxnard at the beach. No, we're talking Oxnard in the onion fields!

Bernadette: Sheldon, when was the last time you got any sleep?
Sheldon: I don't know. 2 or 3 days. Not important. I don't need sleep, I need answers. I need to determine where in this swamp of unbalanced formulas squatteth the toad of truth.
Penny: Toad of truth? Is that a physics thing?
Leonard: No, that's a crazy thing.

George Sr.: [on video] I know we're down, by a lot. And if I'm being honest with you, we're probably not gonna win this one. In fact, we're definitely not gonna win this one.
Amy: Do you want me to turn it off? [Sheldon shakes his head]
George Sr.: [on video] But we're not gonna quit, either. And if we do lose, you need to know that doesn't make you losers. You learn as much about who you are and what you're made of from failing as you do from success. Maybe more. So you can spend the next half feeling sorry for yourselves, or you can get out there and give them hell.
Georgie: [on video] Yeah! Let's give them hell!
George Sr.: [on video] Oh, watch your mouth, your mom might-

Penny: Like, what'd you do last night?
Beverly Hofstadter: I had Cuban food at the home of a man with whom I shared unsatisfying intercourse.
Penny: Wow. Okay.
Beverly Hofstadter: And to anticipate your next questions, roasted pork and sideways missionary.
Penny: Sure. Sure. 'Cause you were full.

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.

Howard: Here's some other fun news on the Raj/Emily front. He gave her a pair of diamond earrings and leased her a car.
Penny: You're kidding.
Leonard: You think she's taking advantage of him?
Penny: Oh, of course not. She wouldn't do something like that. She's deaf.
Leonard: Deaf women can't be gold diggers?
Penny: Handicapped people are nice, Leonard. Everyone knows that.

Leonard: What would I even say?
Sheldon: "Zack, I'm sorry you're stupid. Have a Milk Dud."
Raj: A Milk Dud?
Sheldon: Yeah, Milk Duds, with their self-deprecating name and remarkably mild flavor, are the most apologetic of the boxed candies.
Leonard: I got a better idea. Were all responsible. I say we all go. Come on, who's with me? Free comic books to anyone who comes with me. I might get punched. You really want to miss that?
Raj: Junior Mints are pretty apologetic.
Sheldon: You're embarrassing yourself.

Howard: The man impersonating a bear would like you to know that, "Only you can prevent forest fires."
Raj: I don't get it.
Howard: You didn't have Smokey the Bear in India?
Raj: No. Was he anything like Munmun the Mongoose? He taught us not to play with cobras.
Howard: You had to be taught not to play with cobras?
Raj: You had to be taught not to burn down the forest?

Sheldon: Sheldor, back online.
Penny: What's AFK?
Sheldon: AFK. Away from keyboard.
Penny: Oh, I see.
Sheldon: What does that stand for?
Penny: "Oh, I see"?
Sheldon: Yes, but what does it stand for?