It is also very telling about Holden\'s character that he shows so much disdain for actors. He says the worst is when an actor KNOWS he is good. However he takes on several different personae throughout the novel. It is more than mere lying. He is escaping the trap of being himself by acting as an “other”. He even brags about how convincing he is at it. He demonstrates the same arrogance that he despises so much.
It kind of stands to reason that Holden, who is so sensitive to "phoniness" in anyone, would dislike actors, whose job it is to pretend to be someone they are not. He says, "I hate actors. They never act like people. They just think they do...if an actor acts (a part) out, I hardly listen. I keep worrying about whether he's going to do something phony every minute" (Chapter 16).
Holden also thinks actors tend to be big-headed. He explains, "if any actor's really good, you can always tell he knows he's good, and that spoils it" (Chapter 16).