Sheldon: I was hoping by admitting my weakness to you, I'd somehow be unburdened.
Bert: Is it working?
Sheldon: No. Now that you know my weakness, I hate you more than ever.

Bert: Well, you know, we're both pretty smart. I bet if we put our heads together, we could come up with a solution.
Sheldon: Well, hang on. You're my enemy. Now, the enemy of the enemy is my friend. And right now, I'm my own worst enemy. That makes you my fr-- Okay, I'm good to go.

Bert: Sheldon wait. You know, you've got a lot to be happy about. You're at the top of your field, you have a great girlfriend.
Sheldon: Yes! That's right! I have Amy! In the past, you've professed feelings for her. Does it eat you up inside that I have her and you don't?
Bert: It used to. But now that I'm rich and successful, I think I can do better.

Stephen Hawking: Hello, Sheldon.
Sheldon: Professor Hawking!
Stephen Hawking: I understand you're struggling with professional jealousy.
Sheldon: Thanks, Leonard, now he's not gonna think I'm cool.
Stephen Hawking: Don't worry, I know how you feel. I have never won a Nobel Prize.
Penny: Oh, wow, that doesn't seem fair.
Stephen Hawking: It's fine. I've been on The Simpsons.
Sheldon: How do you deal with the success of your colleagues?
Stephen Hawking: I remind myself every scientific advancement is a victory. Also, I was on Star Trek.
Leonard: (To Penny) Oh, it was a good one. He played poker with Sir Isaac - You don't care.
Stephen Hawking: Don't waste your time on jealousy, Sheldon, you're too brilliant.

Amy: How can you feel bad if Stephen Hawking says you're brilliant?
Sheldon: I can't. Thank you, Professor Hawking. You are a gift to mankind. There should be statues of you everywhere. You know, the Lincoln Memorial has a big chair. We could swap you right in.
Stephen Hawking: I always thought a motorized toy of me would be cool.
Sheldon: What a wonderful idea! How does this man not have a Nobel?
Leonard: (To Amy) Do not tell Wolowitz.
Amy: Way ahead of you.

Sheldon: Would you care for a brandy?
Amy: I don't think so.
Sheldon: Good choice. It's disgusting.

Sheldon: And you realize what the next step is?
Amy: Set up a second culture and try to replicate our results.
Sheldon: Uh, no. We lock that door, lower our underpants a little, and make a baby.

Raj: Maybe there are other things we have in common. Come dinner-time, do you enjoy eating food?

Penny: How come you never eat broccoli?
Leonard: I'm married, I don't have to be attractive.

Raj: Well, I can't eat like a ten-year-old all the time.
Penny: You're dating somebody! Who is it?
Raj: What? What are you talking about?
Penny: You only watch what you eat when you're afraid you might have to take your shirt off.

Raj: Oh my god, I just got it. Fun onions. Funyuns. Hahahaha!

Amy: Sheldon, I'm not ready to have a baby.
Sheldon: Oh, yes, you are! I track your cycle. For the next 36 hours you're as fertile as a manure-covered wheat field.
Amy: Wow. I can actually feel the egg crawling its way back up.

Sheldon: How much will it hurt?
Amy: It's just a tiny skin sample. You saw me do it to myself.
Sheldon: On a scale of one to ten, where one is a pebble in your shoe and ten is the monkey you thought was your pet biting your face off.
Amy: A two.
Sheldon: Eating a whole Altoid?

Bernadette: Still, I can't believe you can turn ordinary skin cells into functioning brain cells.
Amy: Well, I turned this one into a functioning boyfriend, so sky's the limit.

Raj: It's a gravitational wobble. It could be a sign of an extrasolar planet that may contain life and someday be named after me.
Issabella: Oh well, if it has life, maybe it already has a name, huh?
Raj: Yeah, but it's probably difficult to pronounce.
Issabella: What is your name?
Raj: Rajesh Ramayan Koothrappali.
Issabella: You think it would be more difficult than that?
Raj: Good point.