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

Leonard: Sheldon, we have to do this.
Sheldon: No, we don't. We have to take in nourishment, expel waste, and inhale enough oxygen to keep our cells from dying. Everything else is optional

Wolowitz: I just checked the house. There's probably 20, 25 people in there.
Leonard: You're kidding!
Penny: Is that all?
Leonard: "All?" In particle physics, 25 is Woodstock.

Penny: So, you know, isn't there maybe some way you and Sheldon could compromise on this whole presentation thing?
Leonard: No. Scientists do not compromise. Our minds are trained to synthesize facts and come to inarguable conclusions. Not to mention Sheldon is bat-crap crazy

TBBT Quotes

Mrs. Cooper: Shelly! I'm so glad you're here!
Sheldon: I saw you having naked sex.

Penny: I give up, he's impossible
Sheldon: I can't be impossible, I exist. I believe what you meant to say is, "I give up, he's improbable."