Is there no sense in which we can say, actually no: a culture in which slavery is okay is a flawed culture; it is better to have a culture that does not promote this sort of thing?

I would certainly prefer that the arc of time bend towards people and the environment having more protection/freedom/rights than the other way around, but without an external directive I don’t believe that it’s meaningful to use labels like “correct” in this context. For your specific examples, I would rather say something like “Nazi Germany and the Confederacy were below the contemporaneous and current commonly-held threshold for human rights.” That’s a self-important mouthful, which I already regret typing out.

Any evaluation of another culture is necessarily done through the lens of the evaluator’s opinions and preferences, which are (by default) a product of their home culture. I hope I’m explaining my view clearly; I certainly am not arguing that those societies were not abominable places to live, led by awful people.

This implies that certain cultures’ mores are more correct than others’, which probably feels right to you because those countries’ norms align more closely with yours.

As a vegan, I don’t think is the case! I think our cultures norms around animals does not align closely what feels right to me at all.

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For example there some Indigenous or Inuit cultures in rural Canada or Greenland that still partly live their traditional ways of life. I think those cultures are actually better than ours.

I feel like these two statements are in contradiction? You state that some traditional cultures are better because they align with your beliefs, which was my argument. Again, I’m not saying that those cultures are NOT an improvement over my own in this particular regard, based on my own view of morality, just that my opinion on the subject is my own and not “The Correct Opinion”.

Again, I mean absolutely no disrespect and am just trying to stretch my smooth and rarely-used brain a bit. Feel free to simply ignore me.