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.

Mary: Let's say grace.
Sheldon: Hang on, safety first. [puts mittens on]
George Jr.: When are you gonna get over that?
Sheldon: I would think recent events would make you value protection.
Mary: Enough.

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.

Missy: What's it like to not believe in God?
Sheldon: It's great. Big fan.
Missy: Are you ever afraid you're wrong?
Sheldon: About religion? Never. About other things? Also never.

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: [to Mary] I am behaving no differently than I ever have. Why are you suddenly so worried about me?
Dr. Goetsch: That is a valid question. Has anything changed recently?
Sheldon: Maybe it's hormonal. When does menopause typically begin?
Mary: It is not my hormones.
Sheldon: Well, it certainly isn't mine. I'm showing no signs of puberty.

Sheldon: Mother?
Mary: Yes?
Sheldon: Is it okay if I use a knife to butter my toast, or are you worried I'll do something crazy with it?
Mary: You can butter your own toast.
Sheldon: Oh, good. You see the toast, too. I was afraid I was imagining it.