I fail to see how a "pragmatic" argument could lead to the conclusion that pain is "wrong". Wrongness, by definition, involves a moral judgement (at least in this context).
Don't worry about explaining it to me or persuading anyone of the truth of what you say for a moment. Instead, give me your subjective take on it, your own explanation of why it is wrong for someone to inflict pain upon you. Don't worry about what I think, just lay it out in a way that seems plausible to you - IOW, forget "objective" for a moment, and just give me your subjective opinion.
Well, I guess in order to talk about what is wrong, I should first talk about what is right. While still avoiding any talk about religious details of our origin, I should think that someone with even the mildest of religious stirrings (be they monotheistic, pantheistic, or something even less defined than that) would understand right away that regardless of how we were created, or even if we were "created" as such, our existence is a sacred thing, an end in itself. It's not just a condition, like a computer being on or off, or an atomic electron being in an excited state or a ground state. Our existence is the source of everything that we could possibly find worthy - every sense of joy, fascination, and yes, even pain (to the extent that it's not deliberately inflicted), are such immeasurable gifts that flow from it. There can really be no higher earthly purpose than to preserve such gifts, and to enable them to be used in as much freedom as possible. This is where morality begins. Certainly people's understanding of it can be liable to going off in several directions from there, some of which may be sound, some of which may be delusional. Certainly it may have to be compromised in certain situations that we call "necessary evils" (such as fending off invasion). But this is the foundation, and it is real.
Perhaps people weren't willing to accept it because it was hazardous to the survival of the society - certainly it was hazardous to many of the individuals within it. It's kind of hard to build a viable society that is predicated on mass-murder, as we have seen (too) many times.
So how do you say "circular argument" in Latin? ;*P The reason, in the case of the Nazis, why it was so hard for them to build such a society is that people fought it. They didn't accept it. It certainly wasn't that depopulation simply reduced their numbers to the point where society couldn't function; there were still plenty of people left over, so that wasn't the issue at all. If not for people's unwillingness to accept it, there's little reason that I can think of why it wouldn't have produced a very formidable society. So morality really can't be understood in terms of what promotes social survivibility. It can only be understood in terms of the inherent goodness of life, as I described above.
I fail to see how a "pragmatic" argument could lead to the conclusion that pain is "wrong".
It's essentially just a restatement of what I said above. I do not wish to be harmed. In a society where people are free to harm one another, I am likely to be harmed. The consensus view is that most people agree with me in not wishing to be harmed. Therefore, we define causing pain to others as being off-limits, by defining the causing of pain to others to be "wrong".
I should think that someone with even the mildest of religious stirrings (be they monotheistic, pantheistic, or something even less defined than that) would understand right away that regardless of how we were created, or even if we were "created" as such, our existence is a sacred thing, an end in itself.
Wellnow, that gets back to the subject of evolution in a way, doesn't it? It seems to me that if evolution via natural selection is the correct description of how we came to be, then it doesn't make much sense to define us as an "end" at all, in much the same way that no other form of life is really an "endpoint". We may define our current existence as sacred and an end unto itself, but if we step back and look at the big picture, that's purely an arbitrary decision.
The next question I would ask you then is - why is life sacred?
If you accept, a priori, that life and human existence has some grand meaning, then your argument makes sense. But if it is not the case that we are particularly special, the rationale for morality in this sense falls by the wayside.
So how do you say "circular argument" in Latin? ;*P The reason, in the case of the Nazis, why it was so hard for them to build such a society is that people fought it. They didn't accept it. It certainly wasn't that depopulation simply reduced their numbers to the point where society couldn't function; there were still plenty of people left over, so that wasn't the issue at all. If not for people's unwillingness to accept it, there's little reason that I can think of why it wouldn't have produced a very formidable society.
Except that this is almost exactly what I said - I think you and I are not far apart at all here. People didn't accept the Nazi regime, for whatever reason, and so the society was not viable in the long term. Saying that if not for people's unwillingness it would have worked just fine may be true, but it doesn't mean much in the world as exists. If slaves accepted their status, slaveholding societies would be perfectly viable also, but they don't and they aren't.
So, then, the question is why don't they accept such societies? Pure pragmatism? A sense of universal morality? Something that only appears to be a sense of universal morality, but is in fact based on pragmatic principles produced over millions of years of evolution?
Guess which one appeals to me ;)