While I've never thought about it before this, I do believe that evil is innate. I'd bet that everyone has to deal with the temptation to do evil, to serve yourself before others. It's like Star Wars. The Jedi recognize that evil is innate, and do everything they can to stop their members from falling to the dark side, forbidding love and passion as these emotions lead to selfish temptations. Darkness and evil are in us all, it's our choices that see it remain dormant and safe, or active and flourishing.