Sheldon: One cries because one is sad. For example, I cry because others are stupid and it makes me sad."

Leonard: I hate my name. It has 'nerd' in it. 'Len. Nerd.'

Sheldon: I'm not insane, my mother had me tested!

Sheldon: Hello, I know you're out there. I can hear you metabolizing oxygen and expelling carbon dioxide.

Sheldon: Howard?

• Howard: Yeah?
• Sheldon: Your shoes are delightful. Where did you get them?
• Howard: What?
• Sheldon: Bazinga, I don't care.

Sheldon: You can try, but you'll never catch me. Bazinga!

Penny: What up, Shel-bot?

Sheldon: She calls me moon-pie because I'm nummy-nummy and she could eat me up!

Sheldon: Good morning everyone and welcome to "Science and Society". I'm Dr. Sheldon Cooper, BS, MS, MA, PhD and ScD. OMG, right?

Sheldon: Einstein defined insanity as doing the same thing over and over again and expecting different results. By that definition, Penny is cuckoo for Cocoa Puffs.

Howard: Don't you think I should answer the engineering questions? I am an engineer.

• Sheldon: By that logic I should answer all the anthropology questions because I'm a mammal.

Sheldon: Is my hamburger medium-well?

• Leonard: Yes.
• Sheldon: Dill slices not sweet?
• Leonard: Yes.
• Sheldon: Individual relish packets?
• Leonard: Yes.
• Sheldon: Onion rings?
• Leonard: Yes.
• Sheldon: Extra-breading?
• Leonard: I asked.
• Sheldon: What did they say?
• Leonard: No.
• Sheldon: Did you protest?
• Leonard: Yes.
• Sheldon: Vociferously?
• Leonard: No.
• Sheldon: Well, then what took you so long?

Leonard: Why would you buy peppermint schnapps?

• Penny: Because I like peppermint, and it's fun to say schnapps!

(After complaining of dead pixels on Raj's TV) Sheldon: Oh look, it's Harry Potter and 98% of Sorcerer's stone!

Sheldon: No butts, no cuts, no coconuts.

Howard: Hope you don't mind, I told my girlfriend, *Bernadette, she can join us for dinner.

• Leonard: Sure, the more the merrier.
• Sheldon: Wait, no. That's a false equivalency. More does not equal merry. If there was 2000 people in this apartment right now, would we be celebrating? No, we'd be suffocating.

Sheldon: I promised Penny.

• Leonard: Promised Penny what?
• Sheldon: I wouldn't tell you the secret. (pause) Shhhhh!!!!
• Leonard: What secret? Tell me the secret.
• Sheldon: Mom smokes in the car. Jesus is okay with it, but we can't tell dad.
• Leonard: Not that secret, the other secret.
• Sheldon: I'M BATMAN!!!! SHHHH!!!

Sheldon: (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny, (Knock) Penny.

• Penny: What the hell is wrong with you?
• Sheldon: I’m the Flash. I just knocked 30,000 times.