Sheldon: You know I can't keep a secret!
Leonard: You can if you try. Think about it this way: if I were Batman and you were Alfred, you'd keep that secret, right?
Sheldon: Why do you get to be Batman?
Leonard: Because the Batman has the secret.
Sheldon: Alfred has secrets, too!
Leonard: Like what?
Sheldon: Alfred knows that Barbara Gordon is Batgirl. Which I've now just told to Batman! See, I cannot keep a secret!
Leonard: You can if you try. Think about it this way: if I were Batman and you were Alfred, you'd keep that secret, right?
Sheldon: Why do you get to be Batman?
Leonard: Because the Batman has the secret.
Sheldon: Alfred has secrets, too!
Leonard: Like what?
Sheldon: Alfred knows that Barbara Gordon is Batgirl. Which I've now just told to Batman! See, I cannot keep a secret!
Sheldon : You know I can't keep a secret!
Leonard : You can if you try. Think about it this way: if I were Batman and you were Alfred, you'd keep that secret, right?
Sheldon : Why do you get to be Batman?
Leonard : Because the Batman has the secret.
Sheldon : Alfred has secrets, too!
Leonard : Like what?
Sheldon : Alfred knows that Barbara Gordon is Batgirl. Which I've now just told to Batman! See, I cannot keep a secret!
http://www.tv-quotes.com/shows/the-big-bang-theory/quote_20951.html