Sheldon: Leonard. That's Mark Ha-Ha-Ha. It's-it's Mark Hami-Ha-Ha-
Leonard: Yep. Thank Wolowitz. He set it up.

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.

Sheldon: Why are you crying?
Penny: Because I'm stupid.
Sheldon: That's no reason to cry. One cries because one is sad. For example, I cry because others are stupid, and that makes me sad.

Amy: So are you feeling okay? No wedding jitters?
Sheldon: No. There is nothing in the world that would stop me from marrying you tomorrow, even me from the future coming back to prevent the wedding and the subsequent birth of a child who will destroy humanity.
Amy: Because if you came from the future, that would mean you already went through with the wedding because you believe that time travel is on a closed loop.
Sheldon: I love you so damn much.

Sheldon: Amy, I usually know exactly what to say. But in this moment I have no words.
I guess I'm overwhelmed by you. In a good way. Not in the elevator in the Haunted Mansion way. Even if I can't tell you now how I feel, I will spend my life showing you how much I love you.

Sheldon: Are you having an allergic reaction to my boutonniere?
Leonard: No. I'm just so happy for you. And for me. After today, you are officially - and, more important, legally - Amy's problem.
Sheldon: Don't be silly, Leonard. I will always be your problem.