Leonard: You know, I do understand what you're feeling. My brother and sister's accomplishments have always been held over my head.
Sheldon: How did you deal with it?
Leonard: I wet the bed until college, but I don't think that's a quality fix.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: Penny. We are made of particles that have existed since the moment the universe began. I like to think those atoms traveled fourteen billion years through time and space to create us, so that we could be together and make each other whole.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Howard: What do you think?
Barry Kripke: That ... is ... hilarious! Give me the remote control. I want to drive him into the girls' restroom.
Howard: All right, we're done. It's offensive.

Amy: Bert is studying the way microbes in rocks can survive in extreme environmental conditions.
Leonard: They say it could be a potential indicator of life on other planets.
Penny: You know what, I've met Bert. Isn't he an indicator of life on other planets?
Sheldon: You used to make those jokes about me. Now everything's Bert, Bert, Bert.

Raj: Well, I'm glad to see you moving forward.
Sheldon: Bert did quality research. And he deserves whatever accolades he receives.
Howard: What is going on? (To Leonard) Did you upgrade his software last night?
Leonard: I think he might be learning on his own.
Raj: Then the robot uprising has begun.