Causes of Anger
Anger is a natural and mostly automatic response to pain of one form or another (physical or emotional). Anger can occur when people don't feel well, feel rejected, feel threatened, or experience some loss. The type of pain does not matter; the important thing is that the pain experienced is unpleasant. Because anger never occurs in isolation but rather is necessarily preceded by pain feelings, it is often characterized as a 'second-hand' emotion.
Pain alone is not enough to cause anger. Anger occurs when pain is combined with some anger-triggering thought. Thoughts that can trigger anger include personal assessments, assumptions, evaluations, or interpretations of situations that makes people think that someone else is attempting (consciously or not) to hurt them. In this sense, anger is a social emotion; you always have a target that your anger is directed against (even if that target is yourself). Feelings of pain, combined with anger-triggering thoughts motivate you to take action, face threats and defend yourself by striking out against the target you think is causing you pain.
A Substitute Emotion: Anger can also be a substitute emotion. By this we mean that sometimes people make themselves angry so that they don't have to feel pain. People change their feelings of pain into anger because it feels better to be angry than it does to be in pain. This changing of pain into anger may be done consciously or unconsciously.
Being angry rather than simply in pain has a number of advantages. People in pain generally think about their pain. However, angry people think about harming those who have caused pain. Part of the transmutation of pain into anger involves an attention shift – from self-focus to other-focus. Anger thus temporarily protects people from having to recognize and deal with their painful real feelings; you get to worry about getting back at the people you're angry with instead. Making yourself angry can help you to hide the reality that you find a situation frightening or that you feel vulnerable.