Darwin and Haeckel 1.

Charles Darwin wrote a letter to Ernst Haeckel on the 9th of March, 1864 in which he said,

Dear & Respected Sir

You must permit me to thank you sincerely for the present of your paper & for the Stettin Newspaper. I am delighted that so distinguished a Naturalist should confirm & expound my views, and I can clearly see that you are one of the few who clearly understand Natural Selection.

I feel sure that you do good service by boldly expressing how far you agree with me.

Many men in this country elsewhere really go nearly or quite as far as I do on the modification of Species, but are afraid openly to express such views. I have been particularly struck & interested by your remarks on the individual variability of Sapphirina. This sentence will be remembered by me & quoted hereafter.

With sincere respect I remain dear Sir | yours very faithfully | Charles Darwin

In this early letter to Ernst Haeckel, Charles Darwin confirmed that Ernst Haeckel understood him, "one of the few who clearly understands Natural Selection".  It endorses his "boldly expressing how far you agree with me".  He also indicated that Darwinists, five years after On the Origin of Species were already deriving conclusions from it that they were hesitant to make public.

Many men in this country elsewhere really go nearly or quite as far as I do on the modification of Species, but are afraid openly to express such views.

That letter is one in a long correspondence between Haeckel and Darwin,  The Darwin Correspondence Project apparently holds 96, most of which it has not transcribed, many of those are held in the original at Haeckel Haus,.   The earliest collection of Darwin letters published was "The Life and Letters of Charles Darwin" by his son,  Francis Darwin (another of the Darwin children involved with eugenics).  In volume 2,  he warmly testifies to the closeness of his father with Ernst Haeckel.

The earliest letter which I have seen from my father to Professor Haeckel, was written in 1865, and from that time forward they corresponded (though not, I think, with any regularity) up to the end of my father's life. His friendship with Haeckel was not nearly growth of correspondence, as was the case with some others, for instance, Fritz Muller. Haeckel paid more than one visit to Down, and these were thoroughly enjoyed by my father. The following letter will serve to show the strong feeling of regard which he entertained for his correspondent—a feeling which I have often heard him emphatically express, and which was warmly returned. The book referred to is Haeckel's 'Generelle Morphologie,' published in 1866, a copy of which my father received from the author in January 1867.

From this we have his son's evidence that the correspondence with Haeckel lasted the rest of Charles Darwin's life, though perhaps not frequent.  It's possible that there were letters Francis Darwin didn't have when he put together the book.

Francis Darwin said that Darwin and Haeckel's relationship was far more than a mere correspondence, that Darwin hosted Haeckel at his home more than once,  and that he heard him "emphatically experess- "warm feeling of regard"  for Haeckel, "which was warmly returned".  Obviously, Francis Darwin was witness to conversations between his father and Ernst Haeckel.  That is something that no one denying a connection between Darwin and Haeckel can overcome  They never heard the man, never mind lived with him and heard him privately, off the record.   We also learn that Haeckel gave him a copy of "Generelle Morphologie".  The record shows that Charles Darwin was very familiar with Ernst Haeckel's writing up till the time he died.   Of course, Darwin couldn't know what Haeckel wrote after his death but he is known to have read Haeckel through his own words, reaction, commentary and enthusiastic citations.

Francis Darwin consults Thomas Huxley to provide a description of "Generelle Morphologie":

Mr. Huxley, writing in 1869, paid a high tribute to Professor Haeckel as the Coryphaeus of the Darwinian movement in Germany. Of his 'Generelle Morphologie,' "an attempt to work out the practical application" of the doctrine of Evolution to their final results, he says that it has the "force and suggestiveness, and... systematising power of Oken without his extravagance." Professor Huxley also testifies to the value of Haeckel's 'Schopfungs-Geschichte' as an exposition of the 'Generelle Morphologie' "for an educated public."

 Francis Darwin continues about a later letter:

In the following letter my father alludes to the somewhat fierce manner in which Professor Haeckel fought the battle of 'Darwinismus,' and on this subject Dr. Krause has some good remarks (page 162). He asks whether much that happened in the heat of the conflict might not well have been otherwise, and adds that Haeckel himself is the last man to deny this. Nevertheless he thinks that even these things may have worked well for the cause of Evolution, inasmuch as Haeckel "concentrated on himself by his 'Ursprung des Menschen-Geschlechts,' his 'Generelle Morphologie,' and 'Schopfungs-Geschichte,' all the hatred and bitterness which Evolution excited in certain quarters," so that, "in a surprisingly short time it became the fashion in Germany that Haeckel alone should be abused, while Darwin was held up as the ideal of forethought and moderation."]

Despite what is currently believed by some, Haeckel, as early as  "Generelle Morphologie" established himself as the leading representative of Darwinism in Germany, with the approval of Darwin and his foremost English representative.  As Francis Darwin put it:

Mr. Huxley, writing in 1869, paid a high tribute to Professor Haeckel as the Coryphaeus of the Darwinian movement in Germany. Of his 'Generelle Morphologie,' "an attempt to work out the practical application" of the doctrine of Evolution to their final results, he says that it has the "force and suggestiveness, and... systematising power of Oken without his extravagance." Professor Huxley also testifies to the value of Haeckel's 'Schopfungs-Geschichte' as an exposition of the 'Generelle Morphologie' "for an educated public."

Again, in his 'Evolution in Biology' (An article in the 'Encyclopaedia Britannica,' 9th edition, reprinted in 'Science and Culture,' 1881, page 298.), Mr. Huxley wrote: "Whatever hesitation may, not unfrequently, be felt by less daring minds, in following Haeckel in many of his speculations, his attempt to systematise the doctrine of Evolution, and to exhibit its influence as the central thought of modern biology, cannot fail to have a far-reaching influence on the progress of science."


Haeckel could hardly have concluded that he was getting Darwin wrong, between Darwin's confirmation and approval of his aggressive interpretation and Thomas Huxley appointing him the "Coryphaeus [chorus leader] of the Darwinian movement in Germany."  He retained that status for the rest of his life. Charles Darwin never declared him as having gone off the tracks in any document I've seen.

In the letters that follow,  Darwin expresses some reservations about the case Haeckel made for Darwinism, though it's clear that was due to the possibility that it would incite opposition instead of with the scientific validity of what Haeckel said:

CHARLES DARWIN TO E. HAECKEL. Down, May 21, 1867.
Dear Häckel

Your letter of the 18th has given me great pleasure, for you have received what I said in the most kind & cordial manner.  You have in part taken what I said much stronger than I had intended. It never occurred to me for a moment to doubt that your work with the whole subject so admirably & clearly arranged, as well as fortified by so many new facts & arguments, wd not advance our common object in the highest degree.—

All that I think is that you will excite anger & that anger so completely blinds every one that your arguments wd. have no chance of influencing those who are already opposed to our views. Moreover I do not at all like that you towards whom I feel so much friendship shd unnecessarily make enemies, & there is pain & vexation enough in the world without more being caused. But I repeat that I can feel no doubt that your work will greatly advance our subject, & I heartily wish it cd be translated into English for my own sake &that of others. With respect to what you say about my advancing too strongly objections against my own views, some of my English friends think that I have erred on this side; but truth compelled me to write what I did, & I am inclined to think it was good policy.

The belief in the descent theory is slowly spreading in England, even amongst those who can give no reason for their belief. No body of men were at first so much opposed to my views as the members of the London entomolog. Soc; but now I am assured that with the exception of 2 or 3 old men all the members concur with me to a certain extent.  It has been a great disappointment to me that I have never recd your long letter written to me from the Canary I.s. I am rejoiced to hear that your tour which seems to have been a most interesting one has done yr health much good.  I am working away at my new book, but make very slow progress &the work tries my health, which is much the same as when you were here.

Victor Carus is going to translate it, but whether it is worth translation I am rather doubtful

I am very glad to hear that there is some chance of your visiting England this autumn & all in this house will be delighted to see you here.

Believe me my dear Häckel | yours very sincerely | Charles Darwin

Darwin's early expressed reservations of Haeckel's exposition of Darwinism weren't scientific ones:

"It never occurred to me for a moment to doubt that your work with the whole subject so admirably & clearly arranged, as well as fortified by so many new facts & arguments, wd not advance our common object in the highest degree."

Darwin's reservations are explicitly political, the fear of motivating opposition:

"All that I think is that you will excite anger & that anger so completely blinds every one that your arguments wd. have no chance of influencing those who are already opposed to our views. Moreover I do not at all like that you towards whom I feel so much friendship shd unnecessarily make enemies, & there is pain & vexation enough in the world without more being caused." 

Apparently Haeckel had chided Darwin for responding to his critics seriously.  Darwin says that he was doing so as "good policy".

"With respect to what you say about my advancing too strongly objections against my own views, some of my English friends think that I have erred on this side; but truth compelled me to write what I did, & I am inclined to think it was good policy."

He's afraid that if too much of the meaning of Darwinism is revealed, it will excite opposition in the period during which it was gaining ground in England and elsewhere.   So a letter with which his champions try to distance Darwin from Haeckel shows that his hesitations at Haeckel's exposition of Darwinism were political, not scientific.

In the letter Darwin refers to a previous visit Haeckel made to him and he eagerly anticipates an upcoming visit.

Another letter ofNovember 19, 1868 from which I have seen one phrase extracted from to distance Darwin from Haeckel is another instance of "quote mining" to support a eugenics-free Darwin.  But a reading of more of what Darwin said shows  when he says "Your boldness, however, sometimes makes me tremble, "  he wasn't talking about Haeckel's more troubling writing.  Darwin was troubled about Haeckel's book because because he was going past where there was current fossil evidence to support his contentions.

Your chapters on the affinities and genealogy of the animal kingdom strike me as admirable and full of original thought. Your boldness, however, sometimes makes me tremble, but as Huxley remarked, some one must be bold enough to make a beginning in drawing up tables of descent. Although you fully admit the imperfection of the geological record, yet Huxley agreed with me in thinking that you are sometimes rather rash in venturing to say at what periods the several groups first appeared. I have this advantage over you, that I remember how wonderfully different any statement on this subject made 20 years ago, would have been to what would now be the case, and I expect the next 20 years will make quite as great a difference. Reflect on the monocotyledonous plant just discovered in the PRIMORDIAL formation in Sweden.

Considering other things that Darwin and Huxley could have trembled about, that doesn't seem worth the effort.

I will be dealing with the strong ties between Darwin and Haeckel this week because this is such a crucial issue in the dispute.  As anyone who looks at the record can see, Darwin's own words and acts, citation and promoting Haeckel's books and his encouragement of what Haeckel was doing,  that connection is clear and undeniable to anyone who doesn't resort to misrepresenting the case or avoiding looking at the evidence.  And Haeckel in 1868 was already saying things that Darwin wanted kept quiet to avoid bad publicity for Darwinism, without objecting to the scientific nature of what Haeckel was saying.  I will go into that in future posts.

Note:  As to the matter of how much of Haeckel Darwin understood in the original German, Francis Darwin excerpts this letter to August Weismann in which Darwin demonstrates he could read technical papers in German, albeit, "so slowly".

January 12, 1877.

... I read German so slowly, and have had lately to read several other papers, so that I have as yet finished only half of your first essay and two-thirds of your second. They have excited my interest and admiration in the highest degree, and whichever I think of last, seems to me the most valuable. I never expected to see the coloured marks on caterpillars so well explained; and the case of the ocelli delights me especially...


While less known to those fighting the Darwin wars,  August Weismann is also an important figure tying Darwin to German eugenics at the beginning of its horrific development and in English speaking countries.  As with George Darwin, I have not concentrated on Weismann and other figures in this controversy yet though I may get around to that in the future.   I will point out that if you do a google search of these, looking for online, primary material, you will find that creationists have looked at those sources already and they use them in their polemics against evolutionary science.   That record has always been out there, it has never been as available in the original documents as it is today, it is not going away.   Scientists who want to protect evolutionary science from political attacks will have to deal with that record and face that the Darwin so many of them grew up with is half of the story at best, a near complete fabrication, most commonly.

Unlike the problem of writing about Schallmeyer for an English speaking audience, that so little of his writing is easily available in English translation,the question of Darwin's relationship with Haeckel is well documented in English, both by what Darwin and others close to him wrote in English and in translations of Haeckel that were made during Darwin's lifetime and which he would have known to have read or mentioned.  The champions of the eugenics-free Darwin will grasp onto any straw to avoid the conclusions forced by that record.  Which doesn't,  in any way, change the record or that it's available to be read and understood and it always will be.