The accusation in the old piece of hate mail was due to me having made my one and only citation of the scholar of the topic, Richard Weikart. I cited him because he had provided a latter that Charles Darwin sent to the law professor at the University of Zurich, Heinrich Fick. Fick had sent an essay of his to Charles Darwin in which he applied Darwin's natural selection to make the claim that military policy which selected the fittest young men to fight in wars and which exempted those who were unfit led to the fittest being more at risk of dying without leaving offspring and the "unfit" remaining alive to cause the dysgenesis of their nation through their presumably "unfit" children. It was hardly a huge jump from Darwin's original exposition of natural selection to proposals for changing legal policy and such practices.
July 26 
I am much obliged for your kindness in having sent me your essay, which I have read with
very great interest. Your view of the daughters of short-lived parents inheriting property at an early age, and thus getting married with its consequences, is an original and quite new idea to me. — So would have been what you say about soldiers, had I not read an article published about a year ago by a German (name forgotten just at present) [Fick identified him as H. Richter] who takes nearly the same view with yours, and thus accounts for great military nations having had a short existence.
I much wish that you would sometimes take occasion to discuss an allied point, if it holds good on the continent,—namely the rule insisted on by all our Trades-Unions, that all workmen,—the good and bad, the strong and weak,—sh[oul]d all work for the same number of hours and receive the same wages. The unions are also opposed to piece-work,—in short to all competition. I fear that Cooperative Societies, which many look at as the main hope for the future, likewise exclude competition. This seems to me a great evil for the future progress of mankind. — Nevertheless under any system, temperate and frugal workmen will have an advantage and leave more offspring than the drunken and reckless.—
With my best thanks for the interest which I have received from your Essay, and with my
respect, I remain, Dear Sir
As Weikart pointed out in the article in which he introduced the letter into the, then current discussion of Darwin's relationship with social Darwinism and eugenics, though the letter had been previously cited in relatively obscure German scholarship, it was unknown to the current English language discourse on the matter. He also points out that its existence made it far more difficult to claim that part of the post-war plaster St. Charles Darwin myth, that he was entirely innocent of holding social Darwinian views and promoting them*.
The hate mail I received didn't refute anything that Weikart said in the article, it condemned my citation of him due to him working through The Discovery Institute as well as being a profesor of history at the California State University, Stanislaus. It's my observation of those who try to give Weikart the cooties that they leave out his working for the Uof C system.
I read the Wikipedia citation used to condemn Weikart to the status of a banned scholar, not to be cited, and read the piece it cited to declare him "controversial". The piece, Does Science Education Need The History of Science makes the declaration:
What can historians of science do to counter this clear misuse of history? Somewhat perversely, much of our community has remained silent over the past decade while antievolutionists have publicly twisted historical fact regarding Haeckel. It took three biologists to set the record straight in 2005. They explicitly made the point that Darwin did not in fact rely on Haeckel but, rather, on information taken from the antievolutionary Karl von Baer...
[ I am going to break in at this point and say anyone who claimed that Darwin didn't rely on Haeckel for much of what he claimed about the action of and implications of natural selection in the human species is either guilty of the grossest negligence in reading what Darwin, himself, in his major work on that very topic, natural selection as it concerns human beings, The Decent of Man, said, In that work, in which he not only repeatedly credits Haeckel's work with the most effusive of glowing citations - even on such topics as the desirability of allegedly eugenic infanticide and the extinction of human groupings - but in his introduction he said:
This last naturalist,[Ernst Haeckel] besides his great work, 'Generelle Morphologie' (1866), has recently (1868, with a second edition in 1870), published his 'Naturliche Schopfungsgeschichte,' in which he fully discusses the genealogy of man. If this work had appeared before my essay had been written, I should probably never have completed it. Almost all the conclusions at which I have arrived I find confirmed by this naturalist, whose knowledge on many points is much fuller than mine. Wherever I have added any fact or view from Prof. Haeckel's writings, I give his authority in the text; other statements I leave as they originally stood in my manuscript, occasionally giving in the foot-notes references to his works, as a confirmation of the more doubtful or interesting points.
You could only claim that Darwin hadn't relied, very heavily on Haeckel if you either neglected to read the foremost document you would have to have read to make any credible claim on the matter or you would have had to lie about what Charles Darwin, himself, said on that topic, repeatedly throughout the book.
Now back to the paper.]
...They further noted that the creationists “are deeply confused or intentionally confusing regarding the history and significance of this well-known field.”
This preoccupation with Haeckel is taken a stage further by Richard Weikart, a senior fellow of the Discovery Institute, the leading organization promoting and funding the dissemination of intelligent design. In his provocatively titled From Darwin to Hitler: Evolutionary Ethics, Eugenics, and Racism in Germany, Weikart implicitly indicts Darwin and Haeckel for acts that occurred long after their deaths. In line with older creationist claims, we are asked to reject modern scientific theories because of how older versions of these theories were misused. Unlike the claims regarding Haeckel’s embryology, Weikart’s claims regarding a lineage from Darwin to Hitler via Haeckel have been examined by historians of science and indeed have generally been found lacking. Numerous reviews have accused Weikart of selectively viewing his rich primary material, ignoring political, social, psychological, and economic factors that may have played key roles in the post-Darwinian development of Nazi eugenics and racism. Since there is no clear and unique line from Darwinian naturalism to Nazi atrocities, useful causal relationships are difficult to infer; thus, as Robert J. Richards observes, “it can only be a tendentious and dogmatically driven assessment that would condemn Darwin for the crimes of the Nazis.”
The fact is that Robert Richards is far more a revisionist of history than Richard Weikart, his attempted rehabilitation of Ernst Haeckel far more fits the accusations than does Weikart's work. The best proof of that is what I've always advocated people do CHECK THE CLAIMS OF SCHOLARS AGAINST WHAT THE PRIMARY DOCUMENTATION ACTUALLY SAYS. The inescapable fact is that by the 1870s Haeckel was using natural selection in advocacy of people being killed with claims that the effects of that murder was beneficial for the survivors - those who would do the killing. That is the basic act of all genocide, including that of the Nazis. Haeckel did an enormous part to introduce that idea into German intellectual life and more generally into German language popular culture. THE FACT IS THAT WE KNOW CHARLES DARWIN KNEW THAT BECAUSE HE CITED HAECKEL TO MAKE THE SAME CLAIMS IN THE DESCENT OF MAN.
There is something really rather funny about the accusation in this paper against Weikart in that before the section I just quoted it complains.
There is a long— but poorly evidenced—tradition of claiming, for example, that Karl Marx and Friedrich Nietzsche were followers of Darwin...
If they had bothered to look at Weikart's dissertation "Socialist Darwinism" they would have read a far more nuanced view of the very complex, hardly uniformly supportive, but very real relationship that Marx and Engels had with Darwinism, presented in great detail by Weikart. While you get the feeling that the authors of the critique yearn for a simple, black or white reading of that history, it is far more complex and nuanced than is convenient for them. Ironically, for them, Weikart notes in detail that the use of Darwinism by Marxists as a general support of their materialism ** (though not so much Marx) wasn't generally biological, they rejected the very Malthusianism that Darwinism is founded on.
Weikart also noted that Darwin, Haeckel and other member of the Darwin inner circle, like Thomas Huxley certainly didn't return any compliments that many socialists of various kinds and Marxists gave them in the general support for materialism they took from natural selection. I read Weikart's dissertation last month and found it was excellently supported and reasoned and entirely balanced and fair in its claims and conclusions, not at all like the paper used to condemn Weikart, or, in fact, much of any of the effort to distance Charles Darwin from the terrible history of application of his theory to real people.
If you want to read what Weikart wrote about the links between Charles Darwin' theory and the line of German thinking that began, almost immediately, to associate natural selection with advocacy of genocide, you can read his paper Progress through Racial Extermination: Social Darwinism, Eugenics, and Pacifism in Germany, 1860-1918, which, among other things, explains the "pacifism" of the very same Haeckel who, throughout his career advocated the murder of large numbers of human beings and the salubrious effects of that genocide. Something which Charles Darwin also presented as science in The Descent of Man, citing Ernst Haeckel to strengthen his arguments.*** If you want to distance Darwin from Haeckel, you've got the insurmountable mountain range of his citations of Haeckel AS SCIENCE, his correspondence with him (citing it in full, not the typical Darwin industry cherry-picking and clipping) the testimony of those in the English speaking Darwin circle, including his own sons who noted the close relationship and even friendship of Darwin and Haeckel and just about all of the primary evidence. And not only those links with German eugenics and calls for genocide, but others such as are documented in primary sources, such as those Weikart cites.
Charles Darwin didn't even have to know, know about or even be alive for his theory of natural selection to have been the inspiration of specific eugenic proposals, either through forced or coerced sterilization or even by actual legalized murder, all anyone has to do to make that connection is to cite natural selection as supporting their eugenics. They don't even have to cite Charles Darwin by name but merely the idea he created and promoted that it was scientific fact that the deaths of anyone deemed to be a lesser specimen of humanity before they could have children was generally beneficial for society at large and the surviving population. In that scheme of things the survivors will include those who plan and carry out that murder - in fact their success in doing so is one of the traits of their superiority. If they were inferior they would not succeed and would be the ones killed. That is Darwinism as applied to the human species.
If you want to turn a scholar like Weikart into a banned person who can't be cited, you have to do so on the actual basis of their scholarship and their citations, not on a general claim that it is "controversial" or claimed to be such by clearly ideologically motivated ginners up of such "controversy". I'm not going to play that game, anymore. Not even if someone works at the Discovery Institute. If we were to blackball all scholars based on their employing institutions having unsavory associations, I'd have to give up citing people who work at places like MIT and the University of Chicago, Harvard and Yale. With its association with Trump, The University of Pennsylvania would be suspect. The direct links between Nazi eugenics and Cold Spring Harbor Laboratory are undeniable. Should anyone who is associated with it be intellectual kryptonite too?
I chickened-out on that account in the past, I'm done with it now.
** Thomas Huxley may have been an even earlier advocate of the idea that natural selection would inevitably lead to genocide and that the effects of that genocide for the survivors - in his case he explicitly said those would be white people who benefited from the slaughter of former slaves - would be entirely beneficial. His argument was based on the economic utility of slaves and how, with a loss of that economic value to white people, they had no reason to keep them alive. It's a really peculiar, viciously racist version of "white-mans' burden" and an encouragement to throw it aside through murder, all based on natural selection.
*** In the book Darwin cited most heavily in Descent of Man, Haeckel's Naturliche Schopfungsgeschichte, Haeckel prominently and repeatedly credits Charles Darwin and his theory of natural selection with the "final triumph" of the materialist monism which Haeckel shared with the very Marxists and many (though hardly all) of the socialists he despised. Darwin nowhere in anything have ever read of him objected to Haeckel having credited him with that final confirmation of materialist totalism. As Weikart notes, Darwin, Haeckle and Huxley all rejected socialist and, later Marxist economics, in fact the evidence would indicate that they even rejected egalitarian democracy on the same basis of natural selection. Haeckel explicitly stating that rejection, Thomas Huxley explicitly doing the same and Charles Darwin's declaration to Haeckel that he agreed with everything he said in his "Freedom in Science and Teaching" where he made that declaration.
I think the logical case is that you can't believe that natural selection is the basis of evolution while also believing in egalitarian democracy. That rejection of egalitarian democracy is certainly more in line with the actual history of Darwinism than the conveniently held logical disconnect that asserts the ideas are compatible, the currently held conventional dogma of dishonest Darwinist discourse.