Individual human nature is only one factor here; individually, most humans are mindless sheep, little sponges that absorb their attitudes and values from their social environment and then espouse them, unquestioned. Having said that…our individual nature is to desire autonomy (we hate being coerced), we want to be liked, and if things are going our way we are more inclined to be “likeworthy” than abrasive to each other, although for various selfish reasons we can be quite willing to hurt each other.
Socially, our nature is such that we are interdependently social in a way that no other non-insect species is. There are dozens (possibly thousands) of ways to pack us together in a social arrangement, each with consequences for how individuals will perceive their own selfish interests and whether or not those perceptions will lead us to hurt each other more often or less often.
The hypothetical ideal would seem to be the minimally coercive, maximallly co-equal mode, in which being a voluntary cooperator and an all-around likeable person has the highest potential for causing others to do well for you. Systems that utilize other motivational forces, whether positive (bribery) or negative (punishment), dilute the power of reputation as good person / good cooperator and make it more likely that attending to these other factors and forces is the best route to achieving what one wants for one’s personal selfish old self. Money is one example; avoiding political persecution for failing to hate those you are supposed to hate is another.
Most non-cynical politics is an attempt to formulate the ideal means of packing folks so that we are maximally encouraged to treat each other nicely rather than stab each other in the back. In its institutionalized form, most organized religion places the emphasis more fully on individual conduct, as if we would attain the ideal system if everyone as an individual would just be nice to each other for a change. Utopian movements are usually an attempt to inspire people to be nice to each other by giving them a vision or diagram of the ideal social system in which being nice to each other would generate these benefits; as with religion, there is the belief that if everyone had the vision and was “one of us”, the world’s wickedness could be ended; but unlike most religion, the inspirational content pertains to a scheme for how to pack us all together. This is what the 60s (and the early 70s which were part of the 60s for all practical purposes) were to many of us.
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