With the rest being arbitrarily assigned by us to ourselves. Typically due to vanity and ego.
Oh ... I disagree with the "arbitrary" ... I think rules are created to solve problems ... we have the rule about pit toilets being so far away from our cooking hearth ... because folks was pooping right there in the kitchen where mama's trying to make us all dinner ... ewwwwwwww ...
I bring up breeding because these rules are the
MOST difficult for man to follow ... "it's hard, man, really really hard" ... television doesn't even show this, the only sex is among the unmarried ... except I guess Al and Peg do it on her birthday ... ewwwwwwwwwwwww ...
The fox-dog's only roll in breeding is getting the vixen pregnant ... she raising the kits alone ... that's what heathen men want ... so child support laws are hardly arbitrary, if you think it's vanity and ego, then fine ... the heathen don't love their children, so abortion is the better option for them ... breed away, we'll stick a tube up there and suck it all out ... easy peasy ...
We may not like the social rules that were in place at the dawn of the Age of Science ... and permanent marriage least of all ... but again, each of these rules was made to solve a problem ... if science provides a better rule, then so be it ...
It took Moses 40 years to cross the Sinai ... it took T.E. Lawrence 40 hours ... that's what science does for us ... but if you hate you wife, go ahead and divorce her ... divorce only against the rules if you're a Christian ...