Mary: I saw a truck outside. What's wrong with the phone?
Sheldon: Nothing. [drill whirrs] Adding a second line.
Lucas: I'm almost done here. Just got to hop up on the roof.
Mary: Hold on. You can't just add another phone line without asking.
Sheldon: I didn't do it. The university did.
Mary: Why would they do that?
Sheldon: I asked them to.
Lucas: Are you some sort of special kid?
Sheldon: You have no idea.
Mary: Shouldn't you be up on the roof?

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]

Mary: Sheldon, faith means believing in something you can't know for sure is real. And right now, I am struggling with that.
Sheldon: So you don't believe in God anymore?
Mary: That isn't something for you to worry about. I need to figure this out myself.
Sheldon: Can I help? Maybe I could provide a fresh perspective.
Mary: I don't think so, baby.
Sheldon: Did you know that if gravity were slightly more powerful, the universe would collapse into a ball?
Mary: I did not.
Sheldon: Also, if gravity were slightly less powerful, the universe would fly apart and there would be no stars or planets.
Mary: Where you going with this, Sheldon?
Sheldon: It's just that gravity is precisely as strong as it needs to be. And if the ratio of the electromagnetic force to the strong force wasn't one percent, life wouldn't exist. What are the odds that would happen all by itself?
Mary: Why are you trying to convince me to believe in God? You don't believe in God.
Sheldon: I don't, but the precision of the universe at least makes it logical to conclude there's a creator.
Mary: Baby, I appreciate what you're trying to do, but logic is here. And my problem is here.
Sheldon: Well, there are 5 billion people on this planet and you're the perfect mom for me. What are the odds of that?

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.

Adult Sheldon: My mother eventually coaxed me back into a car with a trip to RadioShack. She knew I was nervous so she came up with an interesting distraction.
Mary: Baby, how about we play a car game?
Sheldon: I suppose. Can I make it science-based?
Mary: Sure.
Sheldon: I'll say an element starting with "A," then you repeat that and add one starting with "B."
Mary: I don't think I'll get very far.
Sheldon: Great. Then I'll win. Aluminum.
Mary: Okay, uh, you said "A" for aluminum. "B." Is boron an element?
Sheldon: Yes.
Adult Sheldon: It was the beginning of a new tradition. One that would eventually bring countless hours of joy to Leonard on our drives to work. Much like my mother, he never beat me.
Mary: I don't know an element that starts with "D."
Sheldon: I win. That was fun. Round two. Argon.

Missy: And then they crashed into a tree.
Darlene: Oh, no!
Missy: The engine caught fire.
Darlene: My goodness, is everyone okay?
Missy: Thankfully, yes. But I was pretty shook up.
Darlene: Well, don't worry about that test today.
Missy: Thank you for understanding.
Darlene: Mm-hmm.
Missy: Oh, and where are we on homework tonight?
Darlene: Don't push it.
Missy: Right.

Dr. John Sturgis: [on the phone] So, there's no one who can lend you a car?
Meemaw: There is the church shuttle, but that just feels like it's the end of the line.
Dr. John Sturgis: Oh, I wouldn't say that. There's all sorts of depressing steps before the end. You've got full-time nursing care.
Meemaw: Bye, John.
Dr. John Sturgis: Assisted living.
Meemaw: Bye, John.
Dr. John Sturgis: Hospice.
Meemaw: Bye, John.
Dr. John Sturgis: Life support.
Meemaw: Bye, John!
Dr. John Sturgis: Pulling the plug. [chuckles]
Meemaw: Bye, John.
Dr. John Sturgis: Then... you make a miraculous recovery!
Meemaw: Great!
Dr. John Sturgis: But... the hospital bills leave you destitute!
Meemaw: Bye.
Dr. John Sturgis: Bye.