The Catcher in the Rye- Phonies?

Off the top of my head I can only think of one answer, and it is that the notion of everybody being a phony is a logical contradiction. That is, Holden himself is included in everyone. If everyone is a phony, Holden is a phony. Statements which come from a phony are, by definition, phony (if his statements are legitimate, then he is not a phony). So the the statement "Everyone is a phony" is necessarily false. Worse than that, it implies its own opposite, "Nobody is a phony." Thus the contradiction.