Society is an entity of itself, thus we have a nice science to study it called sociology. Anyway, when those groups of humans get together and make their rules there are rules that are universal to all human societies. One, and only one of them, has been what I have been discussing in this thread. The idea that one would feel "guilt" or "remorse" is idealism. Understanding is the only line that must be drawn. Do you understand the rules, not would you feel bad if you broke them, is the question...