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Volume 2 Supplement 2

Special Issue: Transitional Fossils

Illuminating Charles Darwin’s Morality: Slavery, Humanity’s Origin and Unity, and Darwin’s Evolutionary Theory

Adrian Desmond and James Moore, Darwin’s Sacred Cause: How a Hatred of Slavery Shaped Darwin’s Views on Human Evolution. Boston & New York: Houghton Mifflin Harcourt, 2009. Pp. xxi + 485. H/b $30.00

Misinformation concerning Charles Darwin and his social views has been receiving greater currency recently; i.e., he has been called a racist or it is alleged his theories precipitated the growth of racism, seen as a logical consequence of his theory of evolution. A few have tried to link Darwin with the rise of National Socialism in Germany. The fact that Darwin’s cousin, Sir Francis Galton, helped found the eugenics movement in the late nineteenth century has further encouraged those who are not particularly well informed on the subject to assume biological evolution can be linked with social Darwinism, a false application of Darwin’s ideas that attributes the success individuals or groups enjoy to their inherent genetic superiority. Often, it is the result of a lack of sophistication and understanding of Darwin’s contributions to biology. In other instances, such charges have been deliberately advanced in an attempt to discredit evolution by using the well-worn device of personal attacks to discredit the character of Darwin. Despite the baseless nature of these charges, they have damaged Darwin’s reputation, not only among the educated lay public but also among historians, scientists, and other scholars who seem eager for the opportunity to dismiss the “great man” theory they feel is too prevalent in the history of ideas.

Adrian Desmond and James Moore in their latest biography of Darwin, Darwin’s Sacred Cause: How a Hatred of Slavery Shaped Darwin’s views on Human Evolution, seek to correct the inaccurate depiction of Darwin and his status in the Victorian nation of ideas, as well as his reputation today. Their efforts have been assisted by increased accessibility to Darwin’s correspondence, his marginalia in books, his notebooks, and voluminous manuscript material, which have been painstakingly deciphered and transcribed for the past 35 years, and continues unabatedly as an ongoing project. Desmond and Moore’s central argument is quite daring; the primary force driving Darwin—even as a young man—was his detestation of slavery and racism. They assert evolutionists, secularists and even creationists and fundamentalists of all stripes are wrong when they attribute Darwin’s success to “his single-minded pursuit of science,” and that “a zeal for scientific knowledge consumed him, keeping him on target to overthrow God and bestialize humanity” (p. xvi). Acknowledging contradictions in Darwin’s thought and writings—“paradoxical” in Desmond and Moore’s words—nevertheless, they find “a moral passion firing his evolutionary work” (p. xviii), so much so that “human evolution wasn’t his last piece in the evolution jigsaw; it was the first. From the outset Darwin concerned himself with the unity of humankind” (p. xvi).

It is difficult at first to be comfortable with the notion that the rather complex subject of what drove Darwin can be reduced to a simple explanation, seemingly a bit too pat for what motivated such a complicated individual as Darwin. It seems more likely to many, particularly biologists and historians, that what motivated Darwin was his immense curiosity and interest in the natural world, and his privileged background afforded him the opportunity to develop his interests and enhanced the program of experimentation and study he planned for himself. Early on, he manifested interest in natural history while still a boy, collecting and cataloging beetles and engaging in fieldwork with great zest, examining the flora, fauna, and geological formations in his native Shrewsbury (Shropshire), where he spent his formative years. Having stated their aim at the outset, the authors develop their theme slowly and carefully, weaving the details of Darwin’s life—related in many other biographies of Darwin including their earlier celebrated work, Darwin: The Life of a Tormented Evolutionist (1994)—with new information and emphasis on how his opposition to slavery shaped his thinking and resulted in his single-minded effort to develop a picture of the natural world that could counter the prevailing belief in the immutability of species and the superiority of the white race. Their interpretation is not obvious at first because as Desmond and Moore point out, there were contradictions in the views of many of the leading figures of the time. There were people open to the notion of the mutability of species who held racist ideas, and creationists and religious fundamentalists who were committed to ending slavery. So, by proposing that Darwin’s hatred of slavery, as well as all its dehumanizing effects, drove him to find a theory that could explain how humans evolved, appears initially to be too sweeping a hypothesis.

Desmond and Moore logically marshal the essential facts, carefully relating the major events in Darwin’s life and the lives of his grandfather, Erasmus, in addition his mother’s family and his in-laws, the Wedgwoods, highlighting the familiar along with the not so familiar details of Darwin’s life, now from the fresh perspective of his abomination of slavery and racism, and illustrate how their elimination became his “sacred cause.” Darwin’s brief time in Edinburgh is thoroughly discussed, and they suggest these were not wasted years but important in molding Darwin’s character, providing him with a firm background in geology, many different fields of natural history, and exposure to the new science of phrenology: “He read voraciously to start… that would become a lifelong habit. His library cards record subjects ranging from the viscera to insects, philosophy to insects,” (p. 17). Darwin was already predisposed to the abolition of the slave trade because of his family background, with relatives on his father’s side as well as his mother’s opposed to this evil practice. Darwin’s time in Edinburgh was brief but important. It reinforced his ideas and value system despite many countervailing forces there. Edinburgh remained a place of great intellectual ferment in the 1820s, an atmosphere created by the “Scottish Enlightenment” that began in the latter part of the eighteenth century, a phenomenon drawn from the “French Enlightenment” and nurtured by the medical and scientific societies and Edinburgh University. Desmond and Moore fail to mention the “Scottish Enlightenment” in their lengthy discussion and its impact on the crosscurrents of Scottish intellectual life. They do provide some interesting anecdotes not commonly related in prior accounts of Darwin’s life, such as Darwin’s relationship with the “blackamoor” taxidermist, John Edmonstone, who showed young Darwin how to stuff the wild creatures he caught, particularly birds. Because of the rapport they developed, young Darwin learned firsthand that “black and white men possessed the same essential humanity.”

Darwin’s experience in Cambridge is briefly reviewed, along with the role of his mentor, John Stevens Henslow. Although Henslow remained a creationist—along with others, such as geologist, Adam Sedgwick—Henslow nevertheless was committed to the abolition of slavery. The slave trade had been abolished in the United States and Great Britain in 1807, and while Darwin was on H.M.S. Beagle, slavery was eliminated in Great Britain and in all its colonial possessions. During his journey on the Beagle, Darwin vividly observed the harshest aspects of slavery in Brazil, Argentina, and other parts of Latin America and in other places he visited, in the 5 years he spent away from England. Initially, he was not a militant abolitionist in the same manner as some in his family were (particularly the Wedgwoods), but his experience during the years he spent abroad reinforced his antipathy against the cruelty he witnessed first-hand and made him determined to see such injustices abolished. What especially disturbed him was the sight of the children of slaves torn away from their parents. Darwin deplored this practice as well as mistreatment of animals, making him more sympathetic to the idea of not just the unity of all humankind but all creatures large and small.

The turmoil in the United States over the issue of slavery, (as in Britain), preoccupied most of his adult life and influenced his views. His wife, Emma, while not on the whole sympathetic to his evolutionary ideas, remained a committed abolitionist. When he returned to England, Darwin increasingly found himself in sharp conflict with important allies like the foremost geologist of his time, Charles Lyell, whom he revered. Lyell made frequent trips to North America, sometimes traveling to the southern United States where he observed slavery on large plantations. Lyell occasionally made positive remarks about certain aspects of slavery and shared these observations with Darwin, much to the latter’s distress. Beginning in the 1840s, racist ideas became more overt in educated circles as anthropologists proposed that the different races of humans had originated, (i.e., been created) separately. Darwin adamantly opposed this theory, later called polygenism, as opposed to the idea the races had originated from a single progenitor, monogenism: “The unity-of-race thesis, secretly extended by Darwin to a unity-of-life thesis, was wading increasingly against the tide of new scientific thought” (p. 188), and Darwin found it would be better to bide his time in order to gather evidence that would refute these notions. This partially explains his hesitation in writing on the subject of human evolution but it always remained the subject driving his thinking, and he never lost sight of the ultimate goal of tackling human evolution.

The main thesis of Sacred Cause becomes more plausible when the debate between polygenists and monogenists is discussed because it helps solve some of the puzzles that have been raised about Darwin; i.e., why did he work on many seemingly unrelated subjects in the years after his return to England, and what was the reason for his hesitation in writing on the mutability of species and on the origination of the human species? It was not just his reluctance to avoid controversy or to upset the sensitivities of those people he was closest to, such as his devoted wife, Emma.

Darwin devoted his time studying hybridization among different plant and animal species, recognizing when different human races mated, their offspring clearly were fertile. He supplied ample evidence of interspecific sterility in other animals to counter those who suggested that the different races of man consisted of separate species, the result of separate creations. He followed the advice of his good friend, botanist Joseph Hooker, to undertake a complete study of barnacles in order to further establish his scientific credentials before tackling evolution. Darwin took Hooker’s admonition to heart, agreeing with Hooker—in his September 10, 1845 letter—“How painfully (to me) true is your remark that no one has hardly a right to examine the question of species who has not minutely described many.” The authors mention Hooker’s advice but do not cite this particular passage. Instead, they indicate that Hooker “challenged him to describe ‘minutely’ the differences among all barnacle species,” without providing a specific reference or annotation for this remark, (pp.228–229).

Darwin spent a good deal of time working on seed dispersal to explain how closely related plants could be found in different parts of the world. This is why he investigated subjects that initially were not clearly relevant to evolution. Darwin wanted to provide a strong foundation for his ideas about the mutability of species and the unity of life and humankind because he was aware that in the mid-nineteenth century, “the cutting edge of science was becoming less and less hospitable to [his idea of] descent from a single stock” (p. 222).

Darwin’s experiments with different varieties of pigeons were quite decisive. His experiments established that the so-called “fancy pigeons” were not an amalgam of rock doves and wild species, as the pluralists insisted, but the different forms had originated from a single stock like human beings. In addition, he wrote letters to many naturalists and pigeon-fanciers in different parts of the world requesting to send him their own domestic pigeons; i.e., living samples or at least samples of skins and feathers. Darwin’s home was transformed into a research laboratory so he could readily perform these experiments. Thomas Henry Huxley, who became his staunchest defender, initially was reluctant to wholeheartedly embrace how species were formed, but Darwin’s experiments with pigeons were decisive in convincing Huxley (as well as Lyell), and both became firm supporters of the mutability of species.

When Darwin finally was forced to publish his evolutionary views in 1858 and 1859, he avoided the subject of human evolution, although this subject was the driving force behind all the work that he had done so far. In his letter to the co-discoverer of evolution by means of natural selection, Alfred Russel Wallace, on December 22, 1857, Darwin wrote, “I think I shall avoid [the] whole subject, as it was too surrounded with prejudices...” Desmond and Moore note, “the raison d’être of much of Darwin’s work was to be concealed” (p. 290). What was the reason? They suggest that Lyell warned him not to write on man, informing him that Richard Owen got “wind” of what Darwin was up to, so Darwin did not want to add more fuel to those who were gearing to tear into his evolutionary ideas. Also, he initially hesitated to write on human evolution because events in India made it extremely difficult to get crucial information from his reliable source there, Edward Blyth. The tumultuous events of the Indian Mutiny, (which began in January, 1857), made it difficult if not impossible for Blyth to continue sending voluminous observations about animal and human breeds, their history, hybridism, coloring, competition, and sexual traits he regularly sent Darwin, who regarded them as quite indispensable. Blyth’s wife had passed away in 1857, and this may have been a contributing factor in limiting the flow of information Blyth passed on to Darwin.

After publication of the Origin, Darwin wanted Wallace to tackle the subject of human evolution, even offering the latter the use of his own notes. But Wallace’s views on the subject made it clear that he was not the man to undertake this task. Wallace took a rather unfortunate position on the issue of polygenism v. monogenism before the Anthropological Society in 1864, a compromise between the two radically different theories. Additionally, this episode is a reminder to revisionists who insist Wallace was much more progressive in his racial attitudes than Darwin. Darwin and Wallace’s differences over the efficacy of sexual selection in driving evolutionary change also helped convince Darwin he had to tackle the subject of human evolution himself. Desmond and Moore do not mention that in Wallace’s 1864 paper, as well as a subsequent one delivered before the Anthropological Society, Wallace invoked “Providence” to account for the appearance of human traits. Darwin was so distressed by this turn of events that he finally wrote Wallace on March 27, 1869, “I hope you have not murdered too completely your own and my child [natural selection].”

There are minor omissions in this work, and sometimes certain paradoxes are left unexplained, such as the curious fact that the authors do not mention Hooker’s contempt for democracy, his pro-slavery attitude, and his sympathy for the South during the American Civil War until page 356. It is puzzling the matter is not discussed until the very end of the book, and it is equally curious why Darwin did not bring up the subject in his correspondence with Hooker as he did with Lyell. Darwin made it clear how he felt about the subject, even with people whom he respected, such as Lyell, and cared for, like his eldest son, William. Desmond and Moore suggest William Darwin’s flippant comment about a racial atrocity in Jamaica was the defining moment in motivating Darwin to tackle his important work on human evolution, The Descent of Man. So why did Hooker escape Darwin’s wrath? Hooker’s correspondence contains some deplorable racist statements he made to others, yet historians seem to have glossed over his unfortunate beliefs.

There is some problem with the footnotes found at the end of the book, namely their imprecision. Often, only one footnote appears at the end of a paragraph, despite the presence of different facts in the passage; the corresponding note may contain four, five, or sometimes six separate references, so this creates some confusion. Desmond and Moore’s writing style has a rather arch or ironic tone, making it sometimes difficult to follow their train of thought. It is helpful to be conversant with the subjects being discussed. Despite these quibbles, this is a very fine work. Its central thesis, that the abolition of slavery was “Darwin’s sacred cause,” the driving force that made him develop his evolutionary theory, is not obvious immediately, but a patient reading of the authors’ narrative, renders it more plausible. In addition, the pictures and illustrations are first-rate, adding to the appeal of the book, a work suitable for not just historians of science and naturalists but anyone interested in the history and destiny of the human race.

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Correspondence to Joel Schwartz.

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Schwartz, J. Illuminating Charles Darwin’s Morality: Slavery, Humanity’s Origin and Unity, and Darwin’s Evolutionary Theory. Evo Edu Outreach 2, 334–337 (2009).

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