Commenter "Monster from the Id" on Belmont's Lost in Translation:
Evil exists because human beings exist. No other living thing, and no inanimate object, is capable of being, thinking, feeling evil or of committing evil acts. Only us.
"The world" is not a wicked place. And Humanity is not a wicked thing. Evil is just one of many capabilities we possess. We have to recognize it and (if we're sane) choose not to indulge in it. That's not easy. Most of all, we shouldn't deny evil or act all surprised when it turns up. Like it or not, it's business as usual for us humans.
Fortunately, it's not the WHOLE business. We can do better...