Even a system of rules that allows for only that minimum contract is by no means arbitrary, given the alternatives. If a society does not adequately reward productive, pro-social behavior, insists upon distributing resources in a markedly arbitrary and unfair manner, and allows for theft and exploitation, it will not remain conflict-free for long. If its hierarchies are based only (or even primarily) on power, instead of the competence necessary to get important and difficult things done, it will be prone to collapse, as well.
