Thanks for posting this, it's an interesting topic.
Let me break down my thoughts on this with a short essay.
Some would say that the human nature is corruptible, both mentally and physically.
The mind is vulnerable to verbal/non-verbal and subliminal attacks, as well as to exposure to violence or any dangerous context.
The body is vulnerable to diseases, viruses and limited to a certain amount of mechanical resistance.
Now both the mind and the body influence each other, imagine a good health of the mind certainly improves and/or keeps the health of the body, as well as the other way around.
Others would say that the human individual is like the earth, it grows what seed you give it. You feed him love, will give more love; you give him bad treatment, he responds accordingly. Even if you feed the individual mixed seeds, the result is still not favorable.
Now you can imagine what a fierce individual will become after being exposed to torture, or how obedient and ignorant masses have become after being exposed to lies for so many generations.
So now we can conclude the positive/negative side of the human nature is in fact a product of the society and not a characteristic the individual is born with.
Let me know what you think.