Charles Darwin recognized early on the potential for people to oversimplify his writing. In particular, he was adamant that not everything in evolution was the result of adaptation by natural selection, though he worried that others would caricature his work in that way. In other words, Darwin was not as Darwinian as he is sometimes portrayed. The following passage comes from the sixth edition of On the Origin of Species (1872: 421):

“I have now recapitulated the facts and considerations which have thoroughly convinced me that species have been modified, during a long course of descent. This has been effected chiefly through the natural selection of numerous successive, slight, favourable variations; aided in an important manner by the inherited effects of the use and disuse of parts; and in an unimportant manner, that is in relation to adaptive structures, whether past or present, by the direct action of external conditions, and by variations which seem to us in our ignorance to arise spontaneously. It appears that I formerly underrated the frequency and value of these latter forms of variation, as leading to permanent modifications of structure independently of natural selection. But as my conclusions have lately been much misrepresented, and it has been stated that I attribute the modification of species exclusively to natural selection, I may be permitted to remark that in the first edition of this work, and subsequently, I placed in a most conspicuous position—namely, at the close of the Introduction—the following words: “I am convinced that natural selection has been the main but not the exclusive means of modification.” This has been of no avail. Great is the power of steady misrepresentation; but the history of science shows that fortunately this power does not long endure.”

Virtually from the beginning, Darwin was disturbed by the oversimplification of his ideas on natural selection. Likewise, I’m sure he’d be disappointed in how some of his other views (including personal ones) are sometimes portrayed. I have only read a handful of biographies about his life, so I would not call myself a Darwin expert. But he did write a lot, not only in his published works, but also his notebooks and in his correspondence (ex., see the Darwin Correspondence Project). That makes his life particularly rich to historians of science. It also makes his ideas susceptible to being cherry-picked by people with a cursory view of his thoughts to suit their agenda. For example, Darwin has been portrayed as a racist, as the person who laid the groundwork for eugenics, or even the progenitor for Nazism, etc.

On the other hand, in their book “Darwin’s Sacred Cause”, Adrian Desmond and James Moore (2009) argued that one of Darwin’s primary motivations for concluding that evolution had occurred was his personal hatred of slavery. Where this ranked exactly in his hierarchy of motives, I don’t know, but Desmond and Moore make a pretty convincing case that it at least weighed on his mind. They wrote: 

“Human evolution wasn’t (Darwin’s) last piece in the evolution jigsaw; it was the first. From the very outset Darwin concerned himself with the unity of humankind. This notion of ‘brotherhood’ grounded his evolutionary enterprise” (p. xvi).

By emphasizing the common descent of all people, Darwin’s work was aligned with the religiously-inspired abolition movement, which felt that all people came from the same ancestors. However, Darwin went one step further, arguing that not only all people, but all living things shared ancestry, a view that was too radical for many people of his day (and still to this day, sadly). 

It’s not possible to recap their entire book, but there are several convincing highlights. Among them was the fact that several members of his family (including the Wedgwoods) had been very sympathetic toward, and active in, the abolition movement. While a sixteen year-old freshman at the University of Edinburgh, he also paid for several hours of private tutoring lessons in taxidermy from a former Guyanese slave named John. Darwin described these sessions as pleasant and intimate, and Desmond and Moore point to this experience (as well as his travels on the Beagle) as helping Darwin to see similarities in mental faculties among people from different continents.

They also cite an 1833 letter that Darwin wrote to his sister Catherine in England, while he was still traveling on the Beagle as a young man. He mentioned that he has been following the news back home, as attitudes toward slavery were becoming more negative:

I have watched how steadily the general feeling, as shown at elections, has been rising against Slavery.— What a proud thing for England, if she is the first Europæan nation which utterly abolishes it.— I was told before leaving England, that after living in Slave countries: all my opinions would be altered; the only alteration I am aware of is forming a much higher estimate of the Negros character.— it is impossible to see a negro & not feel kindly towards him; such cheerful, open honest expressions & such fine muscular bodies; I never saw any of the diminutive Portuguese with their murderous countenances, without almost wishing for Brazil to follow the example of Hayti; & considering the enormous healthy looking black population, it will be wonderful if at some future day it does not take place.

Here Darwin appeared to be wishing openly for a slave revolt in Brazil against the Portuguese, as occurred in ‘Hayti’ against the French. The sights and sounds of the suffering caused by slavery seemed to have haunted Darwin, even writing decades later about a ‘distant scream’ he had heard while near a house in Pernambuco. He expressed similar sentiments while traveling across the southern hemisphere, sympathizing with the Patagonian Indians against the ‘white Gaucho savages’ (p. 91), the Aborigines against the ‘cruel’ removal policies of Australian Whites, and the ‘ill treated’ Bushmen against the Boers (p. 103). 

Like anyone else, Darwin’s views were not monolithic. To him, physical differences mattered (he often wrote about the physical beauty of the different people he encountered), but more important seemed to be the personalities of specific individuals he met (whether they were cheerful or unpleasant), along with 19th century concepts of ‘civilization’ and ‘savagery.’ There are passages where Darwin described people, such as the Fuegians, as living ‘like wild beasts,’ and being a ‘lower grade’ of human. To modern sensibilities, these descriptions seem harsh. But to Darwin, the reasons for these differences among people seemed to lie not in innate properties of anatomy, or of polygenic separate origins (quite the opposite). Rather, as Desmond and Moore put it, they lay in the more “conventional sliding scale of plastic qualities, behavior, and morality, with their technological and civilizational consequences” (p. 96). Civilized people were simply domesticated varieties of their wilder counterparts. However, to Darwin, ‘civilization’ was often not all it was cracked up to be, as it was often accompanied by cruelty.  

Finally, the “sacred cause” in the title of their book comes from an 1859 letter Darwin wrote to Richard Hill, the first Jamaican magistrate ‘of colour’ who was influential in the anti-slavery movement. Darwin wrote to him:

“I was quite delighted…to hear of all your varied accomplishments and knowledge, and of your higher attributes in the sacred cause of humanity. I am sure I feel grateful to you for all your kind assistance, and I beg leave to remain with sincere respects.”   

It is very difficult to encapsulate any person’s life. It’s much easier to pick a few snippets, as I’ve done here, admittedly, to show just one side of a person. Even Darwin’s biographers, with all the space of a book, must decide which details to include or to cut, and how to interpret and synthesize them. But in the totality of Darwin’s life, there seems a very strong case that he was a kind and sympathetic person. He was curious about human diversity, and the common ancestry of all living things. He tried to make sense of how the world worked, and even went against the grain of many of his peers, often siding with people who did not look or behave exactly like him. He deserves better than to be caricatured and oversimplified.  

Reference 

Desmond A, Moore J. 2009. Darwin’s Sacred Cause: How a Hatred of Slavery Shaped Darwin’s Views on Human Evolution. Houghton Mifflin Link

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