[saberience]

You say "evil" as though it's something separate or different from basic chemical brain processes, i.e. something inherent to the person or something mystical like it came from the devil. There is no such thing as "evil", all our behavior stems from chemical/biological processes in the brain, and if you have a brain defect or chemically imbalances then yes, you too could end up murdering people. Get hit in the head enough times and you can end up murdering your wife and children, evil doesn't come into it.