There are TWO (or more) evils.
There is normal human nature. It is NOT really evil; it is just selfish and greedy and weak.
However, there is extreme evil (e.g. pointless war, slavery) for which ordinary human psychopathy is not a sufficient explanation.
Real evil comes from outside the human species, but operates THROUGH people. There are two (more?) sources of external evil:-
1) A secret race of physical, biological HUMANs live underground. They attack people psychically (e.g. vampirism), using "mind magic".
2) Non-physical, ghost-like terrestrial DEMONs. They attack the human species with mental illnesses and addictions.
ALSO:-
3) Sometimes, an additional evil is biological ALIENs who genetically seeded (a) human bloodline/s.
4) Sometimes, an additional evil is extradimensional ALIENs who mentally overshadow people.
5) Sometimes, an additional evil is the JEWs who seeded the entire white Aryan race, but had been fundamentally "infected...