My fundamental issue here is that you never bridge the gap between describing how different people disagree and concluding that there is no truth about the matter. It is as if I describe all the different views of whether the greeks attacked troy, and then conclude that there is no truth about whether they attacked troy. I would have a big gap in my argument, right? My point with most of that post is that the language you use gives the illusion of that gap being covered (e.g. "acceptable" states your conclusion but is barely different from "accepted" which is the description).

The question of whether morality is culturally determined you answer by defining morality as something that is culturally determined--you would say something like "these rules are an integral part of past societies, there are many different views". But that assumes a definition of morality to start with.

The only direct argument I remember you offering (apologies if I'm forgetting) was a kind of prudential, pragmatic argument that it is better to treat the moral beliefs of other cultures as equally valid so that we can understand and live together. But "it's better to treat" is not the same as "they are".

Your argument against moral facts is that there is no external scale, which is a decent argument I think. It certainly shows that some moral rules are relative. But it doesn't show that all are, or that the important ones are.

I'm objecting to your implied definition of morality. The words we have in our language that have to do with morality came into usage referring to something definite, not relative. It's fundamental to the definition of morality that it refers to facts. That is how we treat it and how we think about it, which is why people independently change their mind about what they believe is moral. And that's where the meaning of words come from. It is not something that can be changed on a whim. Up cannot mean down. I cannot define "my opinion" as "the truth" and then claim that because I believe something, it is true. I cannot say that a brave action is cowardly. And that is what relativism does with morals.

Understand that you can take a moral realist position, and argue that burkha's should not be banned (reenk made very good arguments in that fashion). And in fact if you don't adopt the moral realist position you cannot argue intelligibly against the ban. Because it would be belgium's culture in which it is then moral to ban the burkha. You would be reduced to saying "I don't like that, for no rational reason", or "bah!".

I just feel like the combination of the ambiguous language you use, the fact that some rules are different in different cultures, and the fact that you see it as the only way to treat other cultures with respect rather than being xenophobic is a very powerful bias for you towards a faulty philosophical position. But it's quite possible that you can argue coherently for every belief you have about other cultures from the moral realist position. Perhaps it is a moral truth that cultures must respect each other's rules 95% of the time, with exceptions for killing innocent children for fun, at which point they have an obligation to intervene.