I’m gonna go ahead and say that the overwhelming majority of evil in this world is the result of human ignorance. Some is the result of sociopathic arrogance. Some is harm for harm’s sake. What inspires that level I can’t say for sure.
Some say evil and good are both masks playing the game. I don’t think I can get behind that anymore.
Ahimsa, a life of minimal harm, may be the way to happiness. It’s not an easy way, but it seems to be the right way. You never finish being in the position of making those choices that keep you from adding to evil and feeding benevolence.