The "science" of evil.
It is not just "how good people go wrong" that has interested me, but from personal experience, I have learned that narcissists are a special breed that don't fall into the category of "people"/human in the way that we understand "PEOPLE"/society to be (they don't operate/function as "people"). Just as pyromaniacs and firefighters might regard fire as an "animal", so can evil be regarded as an animal. From personal experience, this "animal" is the life blood of the narcissist. It is their intent to cause evil, terror, abuse, or destruction (to FOIL nobility, goodness and order) everywhere they go because goodness, stability, order, and truth are incompatible with their life. The only exception is that their altruistic endeavors must remain intact. I call their altrustic endeavors a REDEMPTIVE VOCATION because it's not just meant to fool other people, it's meant to fool themselves so that they can continue to think of themselves as "GOOD" (if they didn't have an altruistic vocation, they couldn't redeem their conscience and wouldn't be able to continue their schemes and narcissistic lifestyle. Even hardened criminals don't choose a redemptive vocation, they just own up to being criminals. Narcissists don't behave according to logic, they are illogical, naysayers, NECESSARILY contrary and MUST avoid rationality. Most sane people think in terms of PEACEFUL COEXISTENCE, but narcissists seem to think that the world exists only for them to pillage.
When someone gives us a gift, in order for us to accept it graciously, we have to relinguish a part of our self-sufficiency to do that, the narcissist cannot allow that to happen to them, therefore they must belittle, ridicule, criticize and find fault in the gift OR the giver.
In the movie "Sybil", the woman (childhood education assistant) had about 16 personalities but she was not an evil, abusive person. I don't think narcissists have a double personality because the GOOD lifestyle/personality is meant only to cover up the other (they only have one NATURE but will EXHIBIT/display two personalities).
The reason I think of evil as an "animal" is because IT instinctively knows what it needs in order to continue/thrive. The narcissist is hardly ever (if at all) consciously aware that they must cause and maintain an atmosphere of chaos in order to continue causing evil.
In order for someone to argue unreasonably with another person, they must cause and maintain confusion/uncertainty of communication, make untrue assertions, cause chaos, prevent order and destabilize the issue/situation (in other words,...chaos).
Peace and harmony (peaceful coexistence) are logical, evil is illogical. Evil continues to happen because it's perpetrators don't own up to it, they simply blame it on the devil (redemptive figurehead).