No man can be evil, for Evil is inhuman, all that we aren't.
It has nothing to do with "eating babies" or what not, it has to do with intelligence.
The learned human, will do no wrong, because he knows good, an ignorant human will be a tool of evil.
But it is of his own ignorance, not of his own will, evil is not "human."
So if you want to know "Why is there Evil?"
Then you must first ask "What is inhuman?"
Well, the most basic answer, is ignorance, but it's clearly not that, for ignorance is not the fault of the Human, he must be taught, and taught to
Evil you can say is undefinable to us, we see its effects, though barely, because Humans simply can not fathom it.
We can be led to do some inhuman things, like killing everyone (genocide), but no human, has ever been to the degree of "evil", just ignorant,
arrogant, insane, what have you.
All humans have an excuse for such things, because to be "inhuman", is to not exist. Or to be an alien//robot, something that is sentient or not
human. And these things, these could be evil.
But if we can't be, then it is arguable that nothing living, or maybe nothing of this Universe, can be Evil, so maybe nothing made or concieved or
whatever, by God can be Evil.
So it would be whatever God did not plan, but that has happend. Be it a force, or an event, or a physical trait in the universe.
There, think about that.