Naumu Nistir wrote:
Universal to humans as a product of our shared evolution and experiences, yes. Not universal to things which are not human, nor universal as a product of it being inherent.
"Universal to" I am afraid is a contradiction in terms. Nothing can be universal "to" anything: if a thing is universal, it, by definition, cannot be limited to any class or subset of things.
But, if you are referring to morality here rather than truth, it is not quite clear what you mean about its relationship to things which are not human: by definition, things that cannot make decisions in the light of understanding of how those decisions may affect other things that can make like decisions cannot be moral or immoral: a volcano's eruption is neither moral nor immoral, nor is a comet's orbit nor a bacterium's reproduction. That these things are not moral or immoral is universally true in the sense that it is logically entailed by the nature of morality and by the nature of the things in question. This is not about moral relativity at all, but what it actually means for something to be capable of being moral or immoral.
The way that I know that the society is wrong is that the conditions for them to be right do not exist. The truth value of my claim is not universal, it's universal only within the population of those who perceive morality as a product of the conditions that brought about the perception of morality.
This is not what you actually wrote: you wrote, "truth is a social construct" without any qualification.
The point that you do not seem to have grasped is that for it to be true that it is possible for an entire society to be wrong about anything, truth cannot, as a matter of inevitable logic, be a social construct. If truth really was a social construct, the truth of literally any proposition (including any proposition about whether truth is a social construct) would be whatever any given society deemed it to be. This would allow for a society to deem it true that truth is not a social construct, in which case it would really be true that truth is not a social construct. That, of course, makes the original proposition that truth is a social construct inherently self-contradictory and thus necessarily incoherent.
The truth value of your claim that truth is a social construct cannot but be universal, as any proposition about the inherent nature of truth necessarily is. Claiming that the truth value of your claim about what it means for anything to have a truth value is somehow confined to some subset of the population compounds rather than reduces the incoherency.
Relativism does not mean that anything can be moral or truthful. Just like language; though language is relative not every utterance has meaning, nor does dog mean 'banana' if I want it to (while at the same time, dog only means 'dog' because of its cultural reception).
Language is relative in the sense that the relationship between any given utterance and meaning is determined by a specific subset of a social context: but the truth of any given proposition about a specific language in a specific place and time is universal: that the word "dog" in fact refers to a particular type of animal rather than a bendy yellow fruit in English speaking countries in the early 21st century is a fact that is universally true, and will remain true even if the words "dog" and "banana" become interchangeable by the 22nd century.
However, you cannot simply use this analysis of the meaning of utterances and translate it directly to ideas about morality, as language, unlike morality, is merely symbolic: a word has absolutely no meaning whatsoever, and cannot be conceived of as having any meaning, unless and until someone somewhere positively decides to give it a meaning (and I do not mean to imply that a specific person must purposely plan to give meaning to a word: but some people must actually give a word a meaning). By contrast, the proposition that a person's decision is moral or immoral is perfectly meaningful even before anyone has previously formed an opinion about the morality or otherwise of doing such a thing: the proposition that something is moral or immoral is something that has meaning by itself, and is not merely a reference (as a linguistic construct is) to some other meaning.
Your attempt to compare morality to language appears to be a form of moral positivism (i.e., a claim that morality is whatever people decide that it is). That is not a tenable description of the nature of morality: if morality (that is, morality itself, not the word "morality"
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is nothing more than whatever people decide that it is, the nature of the thing that people are making decisions about, by definition, can be nothing other than the outcome of other people's decisions about morality, which comprises other people's decisions about other people's decisions and so on to infinite regress and therefore logical incoherency. Moral positivism of this sort necessarily entails a denial of the existence of morality (other, perhaps, than as an illusion): what Softgirl I believe described as "moral nihilism".
I should add that it is not absolutely clear that this is actually what you mean, and apologies if it is not, but the attempted comparison with language (which comparison is, for the reasons given above, invalid) suggests that this is what you are suggesting.
You are right that this is incoherent, but it's also not what I'm talking about. I don't doubt that there are people who believe that, and as a relativist I have no problem with saying that they are wrong. Because we are a product of a long development we are limited in how universal a claim we are able to make; recognizing the same conditions in everyone else is not the same as ascribing to it a universal truth value. I cannot decide that murder is morally permissible any more than I can slip on a dog peel without it being incredibly morbid.
It is not clear precisely what you are attempting to claim, but do not confuse, on the one hand, it being practically difficult to discover what in fact is moral with there being no "what in fact is moral" to discover. Without elaboration on the nature of the limits to which you refer when you write, "we are limited in how universal a claim we are able to make", it is difficult to extract any clear meaning from the above.