Act V, Scene I

Hamlet: Why is it so hard for some people to stop being assholes?
Horatio: I don’t know, you tell me.
Hamlet: That’s the thing– no matter how hard I try, I can’t stop acting this way. I know how self absorbed I am. I know I can be cynical, jealous, hateful, even abusive at times. I know that I’m privileged to get away with half the things I do. Self awareness is not something I lack.
Horatio: Then what do you lack? Advancement?
Hamlet: Self control. I lack self control.