Howard: Dr. Schneider?
Dr. Schneider: Oh, hello, Howard.
Howard: What are you doing here?
Dr. Schneider: Um, house call.
Howard: Youre a dentist.
Dr. Schneider: Yes. Yes, I am. (Shouting to Mrs. Wolowitz) I think he's on to us!

Sheldon: Hurry up, find him, find him.
Leonard: I'm trying. Don't yell at me.
Sheldon: For goodness' sake, he's wearing a hat, glasses, and a red striped shirt.
Leonard: I know what he looks like.
Amy: Oh, there he is, I got him.
Penny: Yes, we win again.
Sheldon: How could you not find him?
Leonard: Because he's hard to find. If he was easy to find, the books would be called There's Waldo!

Raj: Oh, my God, you're back. Oh, look at you. You, you look like you grew.
Howard: Yeah. The lack of gravity did decompress my spine, so I'm like an inch and a half taller. I'm going to the DMV tomorrow to get my license changed before I shrink back.

Raj: Oh, uh, come in, come in. Oh, I, uh, I didn't think I was going to get to see you until tomorrow.
Howard: Yeah, well, Bernadette's a little under the weather and my mom's kind of under my dentist.
Raj: Wait, your, your mother is sleeping with your dentist?
Howard: Former dentist. I need a new one now that I know where his hands have been.

Raj: So you're wandering all around by yourself? That's not the kind of hero's welcome an astronaut should come home to.
Howard: It's okay. You know, we space cowboys don't do what we do for glory and fame. We leave that to your rock stars and your athletes and your Howie Mandels.

Howard: (After leaving Raj and Stuart) At least my mother made her boyfriend climb out the window.

Sheldon: Oh, ow, blueberry in my nose, blueberry in my nose!
Leonard: Snort it down and keep eating!

Bernadette: Hey, Howie, how you feeling?
Wolowitz: Better. Much better. The other astronauts held me down, gave me a shot. Oooh. Attention, people of Earth. Tonight, there will be two moons in the sky.
Bernadette: Howie, stop that. NASA's watching this! Put your pants back on!

Leonard: If you want help, just hire a grad student.
Penny: Maybe I could do it.
Sheldon: You, really? You can assess the quality of my work? Okay, um, here. I wrote this when I was five years old.
Penny: A proof that algebraic topology can never have a non self-contradictory set of abelion groups. Im just a blond monkey to you, aren't I?
Sheldon: You said it, not me.

Wolowitz: If I die, promise me you'll never have sex with another man.

Howard: I really miss gravity. Can you drop something so I can watch it fall?
Bernadette: Really, you're serious? Okay.
Howard: Oh, baby, you're killing me.

Sheldon: Are you familiar with the Higgs boson?
Penny: Of course, it is - it's been in the news. And it's a very famous boson.
Sheldon: Nice try.

Penny: You really think there's some kind of scientific discovery in here?
Sheldon: Well, this box only covers my work through nursery school. There's a good deal more to come. I didn't really hit my academic stride until I cut out that time-suck known as playing outdoors.

Alex: Look, Dr. Cooper. I really want this position. It would be an incredible honor to work for a man of your brilliance.
Sheldon: Flattery will not get you this job, Ms. Jensen.
Alex: It's not flattery if it's the truth.
Sheldon: Oh, well, thank you. Welcome aboard.

Alex: I'm Alex, Dr. Cooper's new assistant.
Leonard: Ah, congratulations and may God have mercy on your soul. I'm Leonard.