Would you know evil if it walked up and shook your hand?
The following is paraphrased from William Lashner's "Fatal Flaw"
The submission of will is the start of goodness.
I tell you a person can be evil without cleft feet and a tail. What is it to be evil in this world? It is to have an unsubmitted will, to swear allegiance to nothing but the inner demons of one’s self, and to use every possible means to bend others to those same demons.
The evil all cleverly hide it behind a veneer of good intentions. Nothing exists to temper their desires. Whatever they want is right, whoever opposes them is wrong, everything they do is justified and proper, everything in this universe exists for the purpose of serving them. You can see it in the way they deal with people and the way they deal with problems.
What they do, on the surface, seems righteous but there is always in evil people a desperate attempt to portray themselves as the soul of righteousness. And just as inevitably, whenever a portion of the evil slips from that false cover of propriety, they are quick to angrily blame someone else for the evil deed.