and although a boring read, "Sex and War"
for a different perspective on your statements. The violent impulse is probably available to all humans, and it is plausible to say that all humans under the right circumstances can manifest extreme violence.
So it becomes details. How are the various impulses moderated under various conditions. It is the precise opposite of black and white, in my opinion.
edit: I am not excusing violence or advocating we tolerate antisocial behavior. I am urging compassion and empathy for people whose brains have made one or more decisions devastatingly incorrectly as a result of what may be an extremely tiny variation in programming, or an edge case that caused their brains to make the wrong decision.
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