MonsterCrack wrote:
For jnstance, could such taboos as cannibalism, incest, or, in Muslim cultures, drinking alcohol, be seen as immoral even when the society is all for it?
By definition drinking is immoral within a specific Muslim sect's law. Is this a priori, though? Only from within that culture; therefore it is not universally immoral, nor a priori. The others vary by circumstance and so, also cannot be considered a priori. What most people would consider immoral incest was considered "proper" matchmaking among royal families, although it did prove to be quite detrimental in a fair number of cases. Keep in mind that "back-breeding" is also a crucial part of animal breeding (although in my opinion still rife with the same problems concerning recessive traits and epigenics). Likewise, cannibalism may not always be immoral (desert island, half the boat passengers wash up dead, the others eat them to survive until rescue).
I can't think of a single moral truth that can be completely a priori other than the most basic which is "do the least harm". And even that has certain relative assumptions about our place as humans in nature, etc..
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