Sheldon: Sheldon Cooper does not cry.
Howard: That's true, you'd rust.

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?

Sheldon: Arthur! Arthur, it's me, Sheldon Cooper.
Professor Proton: Trust me, I remember.
Sheldon: This is television legend, Arthur Jeffries. His science show inspired millions of children.
Professor Proton: Hold on, you have a girlfriend?
Amy: Yes, and I've heard so much about you. Hey look, we're wearing the orthopaedic shoes. I can't believe I dress like a celebrity.
Professor Proton: Okay, I get it now.

Amy: (Talking about Howard & Raj) They are going to have sex before Sheldon and I do. I knew it!

Sheldon: Look, a new topical antihistamine with lidocaine. Wow! I can't wait 'til I get a rash.

Leonard: Ooh, Gasex has a new ultra-strength. I guess they really do read their mail.

Sheldon: Hey, isn't that Professor Proton?
Leonard: Oh, yeah.
Sheldon: Look at him just standing in line, like he wasn't moderately famous thirty years ago.
Sheldon: Let's go say hello.
Leonard: Oh, maybe we shouldn't bother him.
Sheldon: I'm not going to bother him. I'm going to talk to him.
Leonard: He thinks there's a difference.

Raj: Excuse me, I happen to be very comfortable with my masculinity.
Howard: How is that possible?

Amy: How do you not know how to use glue? Did you ditch pre-school?
Penny: Yeah, but only because I was dating a second-grader.

Bill Nye: Wow, Arthur Jeffries. It's an honor to meet you. My show would never have happened without yours.
Professor Proton: That's what I told my lawyers.

Howard: Look who's here to put the Jew in Jewellery night.

Amy: Come on, he's a retired kids show host.
Sheldon: That's even worse. Using the sweet candy of science to trick children into loving him. ... Pervert.

Professor Proton: Sheldon, what are you doing here?
Sheldon: I'm sorry, did I wake you?
Professor Proton: Of course you woke me, it's seven thirty.

Sheldon: I would have been here sooner but for some reason your home isn't on this map of Hollywood stars.

Howard: I was going to make a necklace for my mom but unfortunately she doesn't have a neck. She's just chins and fat and feet.