Sheldon: You know, this situation with Koothrappali brings to mind a story from my childhood.
Howard: Oh, goody, more tales from the Panhandle.
Sheldon: That's Northwest Texas. I'm from East Texas, the Gulf region. Home to many Vietnamese shrimpers.
Leonard: Do the shrimpers feature in your story?
Sheldon: No. Anyway, when I was eight, a Montgomery Ward delivery van ran over our family cat, Lucky.
Howard: Lucky?
Sheldon: Yes, Lucky.
Leonard: He's irony-impaired. Just move on.
Howard: Ok, dead cat named Lucky. Continue.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Howard: Sheldon, don't take this the wrong way, but, you're insane.
Leonard: That may well be, but the fact is it wouldn't kill us to meet some new people.
Sheldon: For the record, it could kill us to meet new people. They could be murderers or the carriers of unusual pathogens. And I'm not insane, my mother had me tested.

Leonard: [to a "smiling" Sheldon] We're here to see Koothrappali, not kill Batman.

(Sheldon smiles in a grotesque way).
Howard: Oh crap that's terrifying.