At the root of fear is low self-esteem. This explains why angry people have low self-esteem, are argumentative, stubborn, and quick to flare up yet slow to forgive. Those behaviors are defenses against the underlying fear.
David J. Lieberman (2010). “Find Out Who's Normal and Who's Not: The Proven System to Quickly Assess Anyone's Emotional Stability”, p.20, David Lieberman
