Original Karma

What are the biological or psychological causes of the phenomenon called "original sin" or "karma" in different religious traditions?

We were:

(i) active organisms long before we became reflective subjects;
(ii) necessarily immature and uninformed during several years of upbringing and education;
(iii) divisively indoctrinated from an early age;
(iv) often unempathetic as children;
(v) inclined to learn by imitating...;
(vi) not only subjects but also objects of consciousness, therefore sometimes performing for an audience;
(vii) treated in ways that exacerbated problems instead of resolving them;
(viii) arbitrarily endowed with different intelligence levels, aptitudes, interests, strengths and weaknesses;
(ix) often unaware that our world-view is not simply identical either with other world-views or with the world itself;
(x) inclined to identify with one group as against others.

Motives, experiences and conditioning generate unconscious mental processes that affect conscious thoughts and actions. Thus, there were multiple causes of misunderstanding and conflict even before society had divided into economic classes.