With utmost redundancy, we deduce that moral good is identical to that good for the survival of the group found in selected-for human social capacities — Kenosha Kid
How do you
deduce this? This is precisely the is-ought problem. You have social capacities that are "good for" (contribute to) the survival of human groups, and an explanation for why humans today have those traits (they are the traits that our ancestors had, who became out ancestors because they survived, thanks to having those traits).
But still, someone asks "What ought we do?" and your answer is "We are inclined to do these things." If they ask "Yes, we are inclined that way, but
is that right?" and you say "It's what helped our ancestors survive", you're still dodging the question. Saying something "is" in response to a question of what "ought" is a non-answer, unless you and the audience already agree on some "ought". You give an account on why we probably
do agree on some "oughts", but that account isn't itself any answer to an "ought" question; you could just as validly point out simply that we already agree on an "ought", with no explanation needed, and then proceed from there. The evolutionary cause of our agreement isn't relevant; just the agreement itself is sufficient.
It's like if I ask what flavor of ice cream I should buy, and you tell me "chocolate is popular". Okay? Does that mean I should buy chocolate? Or that I shouldn't buy chocolate? Is popularity a good thing or a bad thing? In this case, the question is a stupid one to begin with, because the person asking the question has way more information about what flavor of chocolate would best please them than anyone else, and the question is probably rhetorical anyway. But that aside, telling them a fact about people's ice cream preferences is irrelevant, unless they already are of the opinion that they ought or ought not follow the crowds. You could tell them some evolutionary fact about why people evolved to crave certain flavors, but still that's not going to help them answer their question.
Consider sight. I look a tree, I see a tree. I look at the human genome and point a load of genes and say these are responsible for this bit of eye, that optical cable, these bits of the brain, etc. You're basically asking me where the picture of tree is. It's not there. The image of the tree is a consequence of the capacities of sight I have inherited via genes selected for because this way of seeing trees is better than my distant ancestor's for human survival. — Kenosha Kid
That's a poor analogy, because you're still entirely within the domain of "is".
A better analogy would be to flip the is-ought divide around the other way. You ask someone a scientific question about how the world is. They reply by telling you about different cultures beliefs on that topic and how it influences their way of life. You ask which if any of those cultures is actually correct about the question of fact you're asking. They tell you a story of how these cultures came to hold those views, because of the way that holding those views influenced their political or moral or other cultural development. You ask again,
What is the truth of this matter?, but all they will tell you is why different people think it's good to believe this or that is the truth. Because they're a social constructivist, who believes that all of reality is a social construct, nothing is actually true or false, there's just different beliefs that are held in different cultures because believing this way or that is important to them for this or that normative reason.
That's really frustrating, isn't it? Someone who won't give you a straight answer to your "is" question, and instead will only tell you why people think you ought to believe this or that answer to it.
I just do it. Or not. Depending on the circumstances. Our bodies have this covered, as they do with so many things, without solely relying on rational input, and irregardless of our post hoc rationalisation. — Kenosha Kid
For the most part this is also true of descriptive beliefs about factual matters. We just observe what we observe in our lives and our brains just intuit what's real and what isn't. And yet there have been huge disagreements about the nature of reality across history, and we eventually developed a method of paying
really close methodical attention to the experiences that
inform those evolved intuitions in order to settle those disagreements, and in doing so developed a much deeper and more nuanced understanding of what is or isn't real than our ancestors had done with hundreds of thousands of years of using the same exact brains with the same exact intuitions and getting by well enough to at least survive on that alone.
I am not saying that we have to do a bunch of heavy thinking about morality every time we make any decision, any more than we need to do controlled experiments to perceive distances from other vehicles on the road: we can just see where things are with our evolved intuitions, on that scale at least. I'm only suggesting that by paying
really close methodical attention to the experiences that inform our moral intuitions, we can make progress settling the huge disagreements that those intuitions have failed to settle, and in doing so develop a much deeper and more nuanced understanding of what is or isn't moral than our ancestors did with hundreds of thousands of years of using the same exact brains with the same exact intuitions and getting by well enough to at least survive on that alone.
Your counter-argument here seems to be that to weigh up, say, whether we should be a welfare state or not be a welfare state, first we must question our social biology which in turn necessitates that we must refer to the human genome which in turn suggests we must figure out our evolutionary history — Kenosha Kid
No, I don't want to bring up social biology or genes or evolutionary history at all. You're the one bringing that up as though it justified any "ought" claims. It explains why people intuitively have the "ought" opinions that they tend to have, sure, but explaining the cause of having an intuition isn't justifying content of that intuition.