No one said anything about grudges being good. I said they are part of human nature. Also what I said was history has been shaped by anger, envy and grudges. I also can't agree with you on War. Everything about your freedom was built on war. If you are in the US. Your current freedom came at the costs of war. War with Native Americans, War with the Mexico, War with France, War with England. War is great it has given us a home, I can walk down the street without fear because of the wars people fought. If you dont think War is good you might want to read about the civil war, or ww2. At no point in history did someone go, "hey you seem like a cool guy do whatever and take however much land of mine you want. I wont hold against you." We have gone off the topic though.

Grudges are to anger what dark is to the night. You can not say they are different. Nor if you lived a long life you can ever say that you dont live with any bitterness or anger everyday. Its just not true. Again I will state that saying you can't grow based on bad feelings or grudges is a misunderstanding of what true human growth is. Your argument feels more like that of a religious person who believe forgiveness is part of enlightenment than that of someone who understands that each person has conflict within them and balancing that is what makes you. No one lives with only joy, if they say that they're lying to themselves.

Finally grudges are a necessary evil because they pushed people to try harder, pushed people to do things they wouldnt have done before. That feeling that caused has been the driving force for a lot things.