Sheldon: Here's the problem with teleportation.
Leonard: Lay it on me.
Sheldon: Assuming a device could be invented, which would identify the quantum state of matter of an individual in one location and transmit that pattern to a distant location for reassembly. You would not have actually transported the individual, you would have destroyed him in one location and recreated him in another.
Leonard: How about that.
Sheldon: Personally, I would never use a transporter because the original Sheldon would have to be dissintegrated in order to create a new Sheldon.
Leonard: Would the new Sheldon be in any way an improvement on the old Sheldon?
Sheldon: No, he would be exactly the same.
Leonard: That is a problem

Leonard: Come on, Dennis, I'll show you the rec center. They've got Nautilus equipment.
Dennis: Do I look like I lift weights?
Leonard: Not heavy ones

Wolowitz: We need a hot 15-year-old Asian girl with a thing for smart guys.
Penny: What?
Leonard: Howard, that's racist. Any fifteen year old girl will do the trick

Leonard: You speak English really well.
Dennis: So do you... except for your tendency to end sentences with prepositions.
Leonard: What are you talking about?
Dennis: That.
Sheldon: He's not wrong

Leonard: Sheldon, don't you think you're overreacting?
Sheldon: When I'm lying comatose in a hospital, relying on inferior minds to cure me, these Jell-O cultures and my accompanying notes will give them a fighting chance

Sheldon: Checkmate.
Leonard: Argh, again?
Sheldon: Obviously you're not well-suited for three-dimensional chess. Perhaps three-dimensional Candyland would be your speed

Leonard: Alright, get some rest and drink plenty of fluids.
Sheldon: What else would I drink? Solids? Gases? Ionized plasma?
Leonard: Drink whatever you want

Leonard: We're going to Long Beach?
Sheldon: No, of course not. There's no Cousin Leo; there's no intervention. Focus, Leonard.
Leonard: Oh, come on.
Sheldon: We just leave the house on Friday night, and we return in the wee hours, emotionally wrung out from the work of convincing Leo to go back into rehab.
Leonard: So, he goes back into rehab?
Sheldon: Yes, but he can relapse if Penny ever invites us to hear her sing again

Leonard: Sheldon, are you worried about your safety?
Sheldon: No, I imagine if you were going to kill me, you'd have done it a long time ago.
Leonard: That's very true

Leonard: Penny, say hello to Leo.
Penny: Hi, Leo. How are you feeling?
"Leo": Have you ever woken up in a flea-bag motel, covered in your own vomit, next to a transsexual prostitute?
Penny: No.
"Leo": Then don't ask me how I'm feeling.

Leonard: How long is [Leo] going to stay here?
Sheldon: He's a homeless drug addict, Leonard. Where's he going to go? Boy, you have a lot to learn about lying

Sheldon: I'm uncomfortable having been included in your lie to Penny.
Leonard: What was I supposed to say?
Sheldon: You could have told her the truth.
Leonard: That would have hurt her feelings.
Sheldon: Is that a relevant factor?
Leonard: Yes.
Sheldon: Then I suppose you could have agreed to go.
Leonard: And what would I have said afterwards?
Sheldon: I would suggest something to the effect of, 'singing is neither an appropriate vocation nor avocation for you, and if you disagree I'd recommend you have a CAT scan to look for a tumor pressing on the cognitive processing centers of your brain

TBBT Quotes

Sheldon: Why do you have the Chinese character for "soup" tattooed on your right buttock?
Penny: It's not "soup," it's "courage."
Sheldon: No it isn't. But I suppose it does take courage to demonstrate that kind of commitment to soup.
Penny: How'd you see it? You said you wouldn't look.
Sheldon: Sorry. As I told you, the hero always peeks.

Penny: Hey, Sheldon, did you change your Wi-Fi password again?
Sheldon: Yes, it's "Penny, get your own Wi-Fi." No spaces.