Moral rules vary with the societies that hold them

The argument

Proponents of this position begin from variation. Practices that one community treats as plainly wicked another has treated as ordinary or even obligatory, and the list is long: who may marry whom, what may be owned, which killings count as murder and which as duty, what is owed to strangers, how the dead must be handled. If morality were a single order waiting to be discovered, they argue, we would expect the record to look like the record of arithmetic, where isolated communities arrive at the same answers because the answers are not theirs to choose. Instead it looks like the record of language or dress: patterned, mutually intelligible in broad outline, and locally various in a way that tracks history rather than discovery. The inference they draw is not that anything goes but that moral rules are the kind of thing societies make. On this reading a rule earns its grip by being taught, enforced, rewarded and inherited, and the sense of its obviousness is the feeling of having been well taught. That is why moral change is possible at all, and why it happens the way it does: not by anyone detecting a new fact about the universe, but by argument, example, pressure and shifting interest until what was unthinkable becomes ordinary. Defenders of the view point out that participants in such a shift almost always experience it as discovering what was always true, which is exactly what a constructed rule would feel like from the inside once it had taken hold. They add that construction does not mean arbitrariness. Human societies face recurring problems, which is why their moral codes converge in outline on prohibitions against indiscriminate violence and betrayal within the group. Convergence of that sort is explained well enough by common problems and borrowed solutions, they argue, without needing to posit an order standing outside every society that holds one.

Premises

Counter-arguments

Critics answer that variation in moral belief no more shows morality to be constructed than variation in astronomical belief shows the heavens to be constructed; people can simply be wrong. They press the hard cases: a society that enslaves or exterminates is not merely following a different custom, and almost nobody is willing to say that its rules were correct for it. If construction were the whole story there would be no standpoint from which to say so, yet reformers in every tradition have claimed exactly that standpoint and have often been vindicated.

Rejecting the premises

[Rejecting P1] Difference in what people believe is weak evidence about what is the case, since communities have differed about the shape of the earth without making its shape a matter of custom. [Rejecting P2] That a belief was taught explains how someone came to hold it, not whether it is true, so the observation leaves the standing of the rule untouched. [Rejecting C] A reformer condemning their own society's settled practice is not reporting local custom but appealing past it, and the fact that such appeals can succeed suggests there is something to appeal to.