The Wild and Woolly World of Nonlinear Dynamics

Young Sheldon 4×18

Sheldon: Is Missy even authorized to put up a sign? And if so, does that mean I can put up a sign?
George: I don't know.
Sheldon: Because if I put up a "Do enter" sign, which sign would have precedence? Do we have a lawyer? I should talk to a lawyer.
George: She's having boy problems. Just give her space.
Sheldon: Emotionally or legally?
George: Emotionally.
Sheldon: Excellent. Ignoring emotions is where I shine.

Sheldon: Why are you taking that down?
Missy: It's time to grow up.
Sheldon: Leave it there.
Missy: You don't even like Cyndi Lauper.
Sheldon: No, but it's part of my daily routine. Every morning I wake up, look over there and wonder, "Why is she standing like this?"

Sheldon: What does that have to do with me?
Meemaw: You're the big brother.
Sheldon: I'm only two minutes older.
Meemaw: Which makes you the big brother, which means that it is your job to look out for her.
Sheldon: That doesn't make sense. Why should random birth order determine moral responsibility?
Meemaw: I don't make the rules, Moon Pie.
Sheldon: Doesn't seem like you make cookies either. What's taking so long?

Sheldon: You're changing, too.
Missy: How?
Sheldon: You like boys, and you're half an inch taller than me now.
Missy: It's called growing up.
Sheldon: Well, I don't like it.
Missy: Trust me, 20 years from now you're not gonna be sitting around, talking about Star Trek and reading comic books.
Sheldon: Would you like to bet on that?
Missy: A dollar.
Sheldon: Hmm...
Adult Sheldon: She still hasn't paid me. And guess who's wearing Star Trek underpants right now.

Adult Sheldon: That's the thing with pool balls and people. They are both... unpredictable.

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