While I would hesitate to take a definite stand as
to whether guilt is a matter of nature or nuture,
I submit that since we have been part of cooperative
groups since the 'tree swinging` days, and since we
are a species with a long rearing period, that
cooperative culture has become part of our
evolutionary baggage in either case.
If you doubt how difficult it is to change habits
of thought & behavior we picked up in rearing,
consider the acrimony of the religious debates
we see in here.