Nice post!
And what's crazy is... to be 'safe', you just have to simply play by the rules of a particular society, subset, village, etc. and it's amazing how those rules could vary so greatly from group to group. We're all humans living on Earth...and yet we haven't even come close to developing a Universal set of rules. The more you think about it, the stranger it gets. You say "artificial" and I interpret this as man-made. Some would like to believe that a Higher being set the moral compass... but again, that's simply not the case as there are 1000's of Higher beings for all different peoples across the globe, playing by different rules. It's a circular discussion. In fact, you could even live completely by your own set of rules, as long as your willing to suffer the consequences of law in the society in which you are playing.