Howard: Sheldon, I'm more than smart enough to take your class.
Sheldon: *Laughs* No.

Howard: Guess what, engineers are just as smart as physicists.
Sheldon: Oh! You take that back!

Sheldon: Amy, please. I am trying to find a way to intellectually emasculate a dear friend of mine.

Howard: And you love the sound of your own voice.
Sheldon: Well, of course I do. Listen to it. It's like an earful of melted caramel.

Sheldon: Wow, pouting and running away actually worked. I must say that may not be a lesson you want to reinforce with me.

Sheldon: So your solution is to promote me and pay me more money, so I can impart my knowledge to the next generation of scientists?
Mrs. Davis: Yes.
Sheldon: You people are sick.

Sheldon: The correct animal for inter-species super soldier is the koala. You would wind up with an army so cute, it couldn't be attacked.

Sheldon: The answer is cuddly soldiers with big flat noses. Moving on.

Sheldon: I'm sensing awkwardness. Am I right?
Amy: Yes.
Sheldon: Swish.

Sheldon: I assume you want to reopen our dialogue about the university forcing me to continue with string theory?
Mrs. Davis: You mean the dialogue that went "Please? No. Please? No. Please? No."?
Sheldon: That's the one. I believe you went last, so, please?

Amy: Sheldon, it's okay with me if you're not perfect.
Sheldon: Amy, can I have one more moment with Leonard?
Amy: Sure.
Sheldon: Amy just hurt my feelings. I wanna break up with her.

Sheldon: I was the nation's smartest caterpillar and after pupating in our nation's railway system, I have burst forth as the world's smartest butterfly.

Sheldon: You know, Sherlock Holmes liked to use cocaine to sharpen his focus. But I'm sure those cool ranch Doritos are doing the trick.

Leonard: So you never went outside?
Sheldon: Or had a single piece of fruit.

Sheldon: Amy, may I please have a moment of privacy to speak with my roommate?
Amy: We're in a moving car! What do you expect me to do, stick my fingers in my ears?
Sheldon: I was thinking put your head out the window like a dog, but that'll work.