Social organisms, including human(s), live collectively in interacting populations.
It is particularly derived from the Italian Socii states, historical allies of the Roman Republic (although they rebelled against Rome in the Social War of 91–87 BC).
Their social characteristics are therefore to a large extent an objectively given fact, stamped on them from birth and affirmed by socialization processes; and, according to Marx, in producing and reproducing their material life, people must necessarily enter into relations of production which are "independent of their will".
Originally the term "socialist" was often used interchangeably with "co-operative", "mutualist", "associationist" and "collectivist" in reference to the organization of economic enterprise socialists advocated, in contrast to the private enterprise and corporate organizational structures inherent to capitalism.
This perspective formed the bulk of the foundation for Karl Marx's materialist conception of history.