Both this post and the one linked seem to be both about fictional utopias for literature, and actual optimal future utopias. These are completely unrelated issues the same way good fictional international conflict resolution is WW3, and good real world international conflict resolution is months of WTO negotiations over details of some boring legal document between 120+ countries.

Well, then I'm puzzled why you didn't reply to these misguided assertions.

In any case, the paper you cite may well be correct point-by-point, but on the whole, it's a lawyerly argument that tries to overwhelm and misguide the readers by amassing a pile of hand-picked one-way evidence that will dazzle them and make them lose sight of the overall balance of evidence. As I wrote in that earlier comment thread in response to similar points:

As for heritability studies, you are certainly right that there is a lot of shoddy work, and by necessity they make a whole lot of wildly simplifying assumptions. If there existed only a handful of such studies, one would be well advised not to take them very seriously. However, the amount of data that has been gathered in recent decades is just too overwhelming to dismiss, especially taking into account that often there have been considerable ideological incentives to support the opposite conclusions.

Looks (though I've barely skimmed it) like good evidence that twin studies say less than one might naively think. Doesn't say anything about Caplan. Care to say a thing or two about what Caplan thinks twin studies say and how it differs from what analysis like that reveals that they say?

(Perhaps I'm just unduly lazy; I was hoping to find an easier way of assessing your claim versus Caplan's than by procuring a copy of Caplan's book, reading it carefully, reading a technical paper on twin studies, examining the particular studies on which Caplan's claims depend, and comparing his use of them with the analysis in the aforementioned technical paper. Of course that's the only way if I want to be really sure, but ... well, I'm lazy and was hoping there might be a shortcut :-).)

Also, twins share their uterine environment.

This wouldn't apply to IVF twins reared apart, but I doubt there's much of that in the studies.

Why's that relevant, when the question is what parents can change by how they treat their children? (It would be highly relevant if the question were "how much of these differences are genetic?", but on this occasion it isn't.)

As I understand it, the strongest evidence for his thesis comes from adoption studies, do you disagree?

This seems plausible on the face of it, but do you have some evidence or argument to back it up?

Caplan is drastically overinterpretting evidence for heredity of features, and his main thesis relies on them far too much.

Thank you!

Do you happen to know anything about the claim that we're running out of the supplies we need to build solar panels needed to tap into all that wonderful sunlight?

Why are we not counting philosophers? Isn't that like saying, "Not counting physicists, where's this supposed interest in gravity?"