In another thread I happened to say, “It is not realistic to be nice to evil.” Those words inspired some pushback.
To me, the most surprising pushback involved a notion that it is wrong to identify evil in the world. The underlying assumption seemed to be that citing evil is polarizing or destabilizing of social order and — in any case — the ability to recognize evil is purely subjective.
I am not convinced. I say of evil the same thing I say of God: You can prove to yourself that evil exists through personal experience, even if you cannot convince others of its objective reality.
Also, it is not necessary to couch the concept of evil in religious or spiritual terms. I don’t recommend secularism in any of its forms for the simple reason that it cuts away the major part of humanity’s heritage. That would be like trying to operate an ISO 9000-based quality system without any record of lessons learned.
But if you are determined to be secular or scientific on the nature of evil, you can be, as Wikipedia shows. My guess is that modern relativism on the nature of evil won’t last long, because the denial of actual human experience always runs out of gas.