Adult Sheldon: In physics, potential energy is a fascinating topic. Objects like springs store energy when they're coiled, waiting to unleash their full potential and soar to the heavens. Would you look at me go! Even in toy form, I'm shooting for the stars. While the potential energy of an object can be measured in absolutes, human potential remains more elusive. Sometimes, people seem to have all the potential in the world, but for some reason stay stuck to the ground.

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.

Georgie: [o.s.] Did you like school?
Dale: Hated it. I quit and I joined the Army.
Georgie: [o.s.] How was that?
Dale: Less girls, more getting shot at.
Georgie: [enters] Well, at least you made it out alive.
Dale: Well, then I got married. Made me kind of miss getting shot at.
Georgie: Have you ever been happy?
Dale: Ooh, let's see. No.

Sheldon: But why are you wasting your time here when you could be doing science?
Dr. John Sturgis: I told you, I'm happy here.
Sheldon: How could you be happy? You have a doctorate in physics, and you're sticking labels to a case of beans.
Dr. John Sturgis: I had to work here a month before they let me use this thing. And yet, I could go buy a real gun on my lunch break. Ha! Texas, huh?
Sheldon: But don't you miss trying to unlock the secrets of the universe?
Dr. John Sturgis: Sheldon, I spent my life chasing theoreticals. Here, I have tangible accomplishments and I get to listen to relaxing Top 40 music. Do you know this band, Air Supply? They're terrific. [sings] ♫ I'm all out of love ♫ ♫ I'm so lost without you ♫ ♫ I know you were right ♫ ♫ Believing... ♫

Dr. Linkletter: So what do we do about it?
Dr. John Sturgis: We sing.
Dr. Linkletter: What do we sing?
Dr. John Sturgis: [sings] ♫ When you're too old to work ♫ ♫ And you're too young to die ♫ ♫ Who will take care of you? ♫ ♫ How will you get by? ♫ ♫ When you're too old to work ♫ ♫ And you're too young to die ♫ ♫
Dr. Linkletter: I don't think I know that one.
Dr. John Sturgis: Hmm. Do you know "Lollipop"?