Adult Sheldon: I didn't realize until years later that my father was only asking questions about lightning and thunder to cheer me up. In fact, he would often pretend to be dumb just to make me feel better.

Adult Sheldon: My father didn't always get the credit he deserved. The advice he gave me actually worked out pretty well. Of course, I never told him.
George: Talked to Billy.
Missy: Why would you do that?
George: No, it was good.
Missy: Stay out of my life.
Adult Sheldon: He may not have been the world's greatest dad. But maybe we weren't the world's greatest kids.

Adult Sheldon: Ignoring things that irritate me isn't my strong suit. Obsessively fixating on them, now that's what gets me out of bed in the morning.

Adult Sheldon: Dr. Sturgis was a wise man. It was a learning opportunity. And when the day comes that I'm wrong, I fully plan to admit it.

Mary: Wait, Georgie. Where's your bag?
Georgie: Don't need one. Got my toothbrush right here.
Mary: What about clothes? A change of underwear?
Georgie: Got it.
Mary: Georgie, you're gonna be gone for two days.
Georgie: I'll turn them inside out.

Adult Sheldon: I never did get to see a launch in person, but that was the best trip I ever had. I wish I had told my father while he was alive.

Sheldon: Schrodinger's cat is a thought experiment. A cat in a box is exposed to poison, and is both alive and dead until it is observed.
Georgie: So the cat's name is Schrodinger?
Sheldon: No.
Georgie: Well, what's its name?
Sheldon: Its name doesn't matter.
Georgie: It does if the cat was dead. Otherwise, what are you gonna put on his tombstone?
George: Not likely the cat's getting a tombstone.
Georgie: It would in a pet cemetery.