Raj: I don't like bugs, okay. They freak me out.
Sheldon: Interesting. You're afraid of insects and women. Ladybugs must render you catatonic.

Sheldon: Scissors cuts paper, paper covers rock, rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitates lizard, lizard eats paper, paper disproves Spock, Spock vaporizes rock, and as it always has, rock crushes scissors.

Howard: You know, I'm really glad you decided to learn Mandarin.
Sheldon: Why?
Howard: Once you're fluent, you'll have a billion more people to annoy instead of me.

Stuart: Oh, Sheldon, I'm afraid you couldn't be more wrong.
Sheldon: More wrong? Wrong is an absolute state and not subject to gradation.
Stuart: Of course it is. It's a little wrong to say a tomato is a vegetable, it's very wrong to say it's a suspension bridge.

Sheldon: I feel renewed. I'm ready to deal with any changes that come my way. [sees Penny] Your hair is different. You changed your hair. I can't take this. I'm out.

Sheldon: Who's ready to laugh? [Leonard groans] Okay. So Feynman, Einstein and Schrodinger walk into a bar. Feynman says, "It appears we're inside a joke." Einstein replies, "But only to an observer who saw us walk in simultaneously." To which Schrodinger says, "If someone's looking in the window, I'm leaving."
Leonard: [chuckles] That's actually funny.
Raj: You should send that to Jimmy Fallon.

Mary Cooper: Thank you, God, for the food we are about to receive and for the nourishment of our bodies and bless the hands that prepared it. Amen.
Sheldon: Given that your hands prepared it, isn't that a little self-serving?
Mary Cooper: You start changing the words to the prayers, next thing you know, you're in a church with a guitar.

George Sr.: [on video] I know we're down, by a lot. And if I'm being honest with you, we're probably not gonna win this one. In fact, we're definitely not gonna win this one.
Amy: Do you want me to turn it off? [Sheldon shakes his head]
George Sr.: [on video] But we're not gonna quit, either. And if we do lose, you need to know that doesn't make you losers. You learn as much about who you are and what you're made of from failing as you do from success. Maybe more. So you can spend the next half feeling sorry for yourselves, or you can get out there and give them hell.
Georgie: [on video] Yeah! Let's give them hell!
George Sr.: [on video] Oh, watch your mouth, your mom might-