Mary: Here's a question for you. Do you ever see or hear things that other people can't?
Sheldon: Oh, all the time. Right now, the car antenna is vibrating at the same frequency as the pistons in the motor. It's quite irritating, but you know me I don't complain.
Mary: I meant more like things that aren't actually there.
Sheldon: Ah, isn't that the fundamental question of modern metaphysics? What is actually there? This is fun. Missy should ride with Dad more often.

Sheldon: Missy and I broke a lot of rules the other night, and we've received no punishment.
George: [sighs] Buddy, it's been a rough week. We're just glad you're both safe.
Sheldon: But in the absence of a divine being, society's rules are what keeps a person's morality in check.
George: Well, there you go.
Sheldon: No, y-you're not following me. If actions have no repercussions, society breaks down, everything devolves into chaos.
George: You might be overthinking this.
Sheldon: I thought so, too. Then I thought about it, and I'm not.
George: Sheldon, you had one bad night. Just let it go.
Sheldon: But... I did something wrong and I got away with it. That's not okay.
George: Buddy...
Sheldon: Socrates maintained that the man who lies to himself has an enemy living within. He's not even a person. He's just a chaos of selfish desires wrapped in an animal hide.

Sheldon: Unbelievable. It's either cartoons or men in their underwear banging their heads together.
Ricky: You complain a lot.
Sheldon: Excuse me?
Ricky: Seriously, dude, you need to relax.
Sheldon: How can I relax? I'm being held captive in a bacterial playground.

Ms. MacElroy: Now, can anyone tell me why Melville shifts the narrative voice from Ishmael to Ahab? [Ms. MacElroy waits for somebody else to raise their hand] Sheldon.
Sheldon: I have a tummyache. I'd like to see the nurse.
Derek: A "tummyache"?
Sheldon: Yes, Derek, I have a tummy and it aches. Ergo, tummyache.
Derek: Ergo?
Sheldon: It's Latin, Derek.
Ms. MacElroy: Go to the nurse.
Sheldon: And to answer your question, the shifting point of view grants the reader a broader perspective of events than typically allowed by first-person narration.
Ms. MacElroy: Where were we?
Sheldon: And "ergo" is Latin for "hence," Derek.

Mary: I was just letting you know that if you were having any problems you could come to me with them.
Sheldon: You think I have mental problems?
Mary: Well, not problems. I'm just worried about your future, and when I see you moving subatomic particles around in the air, that makes-
Sheldon: Subatomic particles are real! You talk to an invisible man in the sky who grants wishes. If anyone's mental, it's you.

Sheldon: Why aren't you also driving Missy to school?
Mary: I thought it might be nice for us to chat.
Sheldon: About Missy? She is a bit much, isn't she?

Meemaw: Smart.
Mary: Thank you.
Meemaw: You're good at lying. You should do it more often.
Mary: I like your earrings.