Amy: Well, as much as we've studied the brain, there's still a lot we don't know about dreams and their function. You know, even psychologists are divided on it.
Leonard: Mm, it's true. Freud thought dreams were about sex, Adler thought they were about dominance-
Penny: Then again, mine are just about being married to this little guy.
Leonard: Well, now it's just edging into mockery.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

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.

Professor Proton: Can I ask you a question?
Leonard: Yeah, sure.
Professor Proton: Why do you put up with Sheldon?
Leonard: Oh, you know because we're friends.
Professor Proton: Why?
Leonard: Wow, you ask really hard questions. Look, I know he can be aggravating, but what you have to remember is he's not doing it on purpose, it's just how he is. But he's also loyal and trustworthy and we have fun together.
Professor Proton: You know you're describing a dog?
Leonard: He did bite me once. But in his defense, I came up behind him while he was eating.
Professor Proton: They hate that.
Leonard: Sheldon is the smartest person I have met. He's a little broken and he needs me. And I guess I need him too.
Professor Proton: Why is that?
Leonard: Boy, you will not let this go, will you?

Bernadette: One of the great things about being pregnant is drinking cranberry juice out of a wineglass and watching people freak out.

Sheldon: I call this meeting of the Council of Sheldons to order. Let's take roll. Science Sheldon?
Science Sheldon: Present.
Sheldon: Texas Sheldon?
Texas Sheldon: Howdy.
Sheldon: Fanboy Sheldon?
Fanboy Sheldon: Greetings.
Sheldon: Germaphobe Sheldon?
Germaphobe Sheldon: Say it, don't spray it.
Humorous Sheldon: Where's Jock Sheldon?
Sheldon: Not the time, Humorous Sheldon!

Sheldon: Why can't there just be one week each month for famous people to die?
Amy: Well, they've already arranged to die in threes. What more do you want from them?