The key to forgiveness is to forgive from the heart not from the mind. Knowing in your rational mind that your parents did the best they could to raise you is not enough to constitute forgiveness. That is why every time you are with your Dad you still argue. If you really forgave him you would not be reacting that way. You would have compassion for his dream and understand that he is just expressing his point of view. If you truly let go of the pain of your childhood, your self importance and your point of view, you would not be taking him personally any more. And it would not be necessary to punish him by behaving like an angry child. It behooves us to look at ourselves with honesty and objectivity. You can say you have forgiven someone in your life, but the proof is in the pudding..so to speak. If you have an emotional reaction in the presence of someone, that is your hearts' way of telling you that you have not resolved your issues with them. In other words you have not truly forgiven that person. Begin by ceasing to lie to yourself and by stopping the stories you create about why you behave the way you do. Stop blaming your behavior on other people and take responsibility for your emotional reactions. If you could forgive all the people in your life who have hurt or wounded you it would be possible to be in control of your behavior instead of being in reaction all the time. Imagine living life not experiencing a constant emotional rollercoaster of pain, anger and jealousy! That would be bliss!