There's a peculiar doctrine coming out of George Mason in recent years. It's called "analytical egalitarianism," and has been energetically promoted by my brilliant colleague David Levy, his co-author Sandra Peart, and quite a few others. (See here and here for the main book-length treatments; see herehere, and here for related Econlib columns). I've read quite a bit of this work, and argued with David in many a seminar. As best as I can tell, analytical egalitarianism amounts to the following:
Proposition 1. All people are equally talented and have the same preferences.
Proposition 2. If people do have unequal talents or different preferences, these are ENTIRELY the result of environmental differences.
Proposition 3. If there are any innate/genetic differences between people, it's exceedingly dangerous for the world if anyone says so.
I'd like to be more charitable, but I can't. The arguments Levy, Peart, and others marshall for the preceding three propositions come down to:
Evidence for Prop. 1. Historical analyses of allegedly innate differences that eventually faded away (like Irish underachievement), and some instances where experts were wrong, and non-experts were right.
Evidence for Prop. 2. Appeal to the authority of Adam Smith and J.S. Mill, such as:
The difference between the most dissimilar characters, between a philosopher and a common street porter, for example, seems to arise not so much from nature, as from habit, custom, and education. (Smith, Wealth of Nations)
Of all vulgar modes of escaping from the consideration of the effect of social and moral influences on the human mind, the most vulgar is that of attributing the diversities of conduct and character to inherent natural differences. (Mill, Principles of Political Economy)
Evidence for Prop. 3. Detailed discussions of the life and works of odious literary figures like Carlyle and Ruskin, as well as various eugenicists who range from boorish to murderous.
I find this evidence underwhelming. Point by point:
Rebuttal to Prop. 1. The fact that some allegedly innate differences went away hardly shows that there are no innate differences. There are plenty of allegedly innate differences that failed to go away, too.
Similarly, the fact that non-experts have sometimes beaten the experts hardly shows that everyone is equally talented and knowledgeable. No one's infallible; you've got to look at average performance (or, if Levy prefers, median performance).
Rebuttal to Prop. 2. Frankly, who cares what Adam Smith and J.S. Mill thought about heredity vs. environment? How can you prefer the speculation of two economists - however brilliant - to the hard facts of modern twin and adoption studies? There is now an overwhelming consensus that genetics explains a great deal about human variation. Smith and Mill were just wrong - though in fairness to Smith, the above quote says only that nature is less important than other factors, not that it doesn't matter.
Rebuttal to Prop. 3. Yes, there have been some loathsome people who have "reasoned" from the fact of innate human inequality to the conclusions of murder and slavery. But these malevolent conclusions do not remotely follow from the premises, as I argued here.
Even more tellingly, there have been plenty of loathsome people who have "reasoned" from the fact of innate human equality to the conclusions of murder and slavery. Check out the Black Book of Communism or my Museum of Communism for details.
The bottom line is that atrocities have been committed in the names of nature and nurture alike. Extreme environmentalism is no protection against man's inhumanity to man. In fact, to defend extreme environmentalism in the face of mountains of evidence from twin and adoption studies implicitly grants the crazy premise that IF non-environmental differences existed, murder and slavery would OK.
Lest I be misunderstood, let me say that many proponents of Analytical Egalitarianism, most notably Levy himself, are extremely smart and knowledgeable. Their very existence is evidence against Proposition 1, because they've got way more than the average endowment of ability. Just like the Austrians, I'm going after analytical egalitarians because they're wasting their talent and energy defending the undefendable.