Or rather, the subconscious evil form of me.
Everyone has one; Remember Kirk in "The Enemy Within"?
To me, knowing the terrible things oneself is capable of, when all the knowledge a person has could be used by that person for wrongdoing, THAT is the most terrifying thing in the whole universe. Just as everyone is capable of great good, I believe everyone is equally capable of great evil. And I certainly know that I am included in the consensus.
"To boldly go where no man has gone before"
--ADMIRAL JONATHAN ARCHER--