Sheldon: Well, all we need is a mainframe computer.
George Jr.: How much is that?
Sheldon: New, about half a million dollars, but I'm hoping to find something slightly used.
[Georgie kicks Sheldon out of the garage]
Sheldon: Time will prove me right.

Principal Petersen: Our next young speaker needs no introduction, but that didn't stop him from writing one and making me read it. [laughter] "Fun fact." [audience groans, murmurs] I hear you. "The word 'valedictorian' is from the Latin 'valedicere,' meaning 'to say farewell.' It is primarily used in the United States, Canada, the Philippines and Armenia." Maybe that fact's more fun in Armenia. Please welcome your valedictorian, Sheldon Cooper.
Mary: Yay, Shelly!
Sheldon: Hello. I'm not very comfortable speaking in front of crowds. But there's a technique to reduce stage fright by focusing on one person in the audience and delivering your speech just to them. That's what I'll be doing today. If it weren't for this person, I wouldn't be here right now. They've taught me a lot, and it's by their example that I found the courage to move forward into this new and exciting chapter of my life. Missy... ...this is for you. Change can be scary, but I know we're going to be fine... ...because like you said, "It's okay to be scared. We just have to do it anyway." So if any of my fellow graduates are nervous about the future, know that you're not alone. I suggest you all try to be as brave as my twin sister. That's my plan. Missy, I wish I could give you advice about middle school, but I was so smart, I skipped it. If you make it to high school, we'll talk. Thank you. [applause]

Sheldon: Missy and I broke a lot of rules the other night, and we've received no punishment.
George Sr.: [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 Sr.: 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 Sr.: You might be overthinking this.
Sheldon: I thought so, too. Then I thought about it, and I'm not.
George Sr.: 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 Sr.: 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.

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.

Meemaw: [on the phone] But I want to be clear, this is just one of those... Whatcha call it... Uh, platonic things. We're just having dinner.
Dr. Linkletter: I'll take it. Now, would you prefer a restaurant or some good home cooking? I make seven kinds of soup.
Meemaw: I think I'll just stick with a restaurant.
Dr. Linkletter: Fair enough, but one day, you'll try my mushroom barley, and your taste buds will swoon.
Meemaw: Good night, Grant. [starts to put down phone]
Dr. Linkletter: The secret is how long I cook the onions.

George Sr.: What are you doing here?
Meemaw: I ran out of beer at home, didn't feel like driving to the store.
George Sr.: Oh, so you just waltz in and help yourself?
Meemaw: 'Bout sums it up. [hands George a beer]
George Sr.: I'm changing the locks.
Meemaw: [laughs] Cheers.

Missy: We could let people punch you for a buck.
Sheldon: No, all our profit would just go to medical expenses.