My strategy is to use logic to break down what both of us are truly saying. Once they realize that their argument is a defense mechanism (in this case) perhaps then he can do the personal growth or reflection on his own. The goal is not to hurt anyone or make them feel guilty; it is to make them see how they can hurt others. It is a learning process; one I go through often. We all need to keep expanding as more caring, loving, and accepting people.