The Descent of Man

"Darwin’s books are a series of masterpieces. From early works such as The Structure and Distribution of Coral Reefs in 1842, to his last, which has the unpromising title The Formation of Vegetable Mould through the Action of Worms , published in 1881, he gives us a truly majestic view of the workings of even the smallest life forms which, however humble they may appear, have global consequences. But yes, as you suggest, the question of man’s place in, and relation to, nature was the big one. Darwin clearly understood the implications of the theory of natural selection from early in his career, writing in a private notebook in 1838, “Origin of Man now proved…He who understands baboons would do more towards metaphysics than Locke…” But he was, at least initially, deeply troubled by the implications of his proof – it was, he later said, “like confessing to a murder” – and he alluded to it only elliptically in 1859 in The Origin of Species , writing that “much light will be thrown on the origin of man and his history.” For a combination of reasons, which Jerry Coyne describes in his interview with Five Books , Darwin held off for another twelve years before publishing a detailed chain of reasoning in The Descent in 1871 and buttressing the case the following year in yet another masterpiece, The Expression of Emotion in Man and Animals. Darwin showed that man was continuous with other animals not just in his bodily form but in his mind and, for want of another word, soul. This was a hugely controversial idea in his day and it remains so for many people in ours (though it has never been a problem for animists or pantheists, among others). Even the co-discoverer of natural selection, Alfred Russel Wallace, and Darwin’s great champion, Thomas Henry Huxley, balked at it. They simply could not believe that the human mind and morality could, just like nipples and noses, have evolved without divine intervention. Perhaps the dark, Malthusian aspect of the theory of natural selection, expressed so vividly in chapter 3 of The Origin , and the “Social Darwinist” vision, which was not Darwin’s own but to which it was quickly linked, was too daunting, and unlike Darwin himself, they failed to appreciate it was an incomplete account. Support Five Books Five Books interviews are expensive to produce. If you're enjoying this interview, please support us by donating a small amount . The Descent of Man develops a fuller conception of how natural selection works. Much of the book focuses on selection in relation to sex – a phenomenon which we may be familiar with through the example the peacock’s tale: the extravagant tail feathers of the male result from female preference. (Interestingly, Darwin suggested sexual selection might explain human music, though most evolutionary biologists would now say that even if correct it is just one among several factors.) But more importantly, at least for my argument here, is what Darwin has to say about cooperation as a factor in evolution besides competition. The key quote, from chapter four, is: “any animal whatever, endowed with well-marked social instincts, the parental and filial affections being here included, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well, or nearly as well developed, as in man.” Paul Seabright explains the implications well in his interview with you : “Darwin was clear that natural selection can select for cooperative and collaborative qualities. But he also points out that the process of selection for cooperative and collaborative qualities is not a serene parade of agreeableness – it’s the result of often violent conflicts. It’s because we live in a world which often has violent conflicts that our collaborative qualities are so important.” An understanding of this reality – the interaction and the tension between competition and collaboration – is crucial to our prospects for growing up in the Anthropocene. The science and mathematics may take us quite some way. Recently, Martin Nowak and others appear to have put a solid foundation under the claim that there is a “snuggle for existence” as well as a struggle for one. It follows, crucially, that it is possible to design systems and rules under which cooperators are more likely to thrive. The logic here applies as much to social and political institutions as it does to the natural world, so it follows that humans can – in the right circumstances and other things being equal – develop smarter systems that favour flourishing for both humans and natural ecosystems. This, at least, I take as the corollary of works such as Seabright’s own book The Company of Strangers: A Natural History of Economic Life and Steven Pinker’s The Better Angels of Our Nature: Why Violence Has Declined . Behind these important works stands Darwin’s The Descent , which I should add is also a very good read."

"Yes, in the sense that we are descendants of other animals. I like The Descent of Man better than The Origin of Species because Darwin is prepared to be much bolder in The Descent of Man . In The Origin of Species he was still a little bit timid. He presents the idea of how species develop, and that is what we now refer to as evolution. But he didn’t apply it to humans. He really didn’t dare to say that we humans developed from other apes just as horses, for example, developed from early proto-horses. He didn’t use the term ‘evolution’ anywhere in the original editions of The Origin of Species . He does use it in later editions, but that’s around the time when The Descent of Man is published. There’s something else that I particularly like about The Descent of Man , one that links with another area of my thinking that we haven’t talked about. Darwin makes an explicit comparison between humans and other animals in terms of their anatomy and physiology, of course, but also in their mental and moral capacities. He brings up the objection that humans could not have descended from animals because our mental powers are different in kind from animals, and our moral nature is also different in kind from anything we can find in other animals. “The value of allowing ideas to be expressed does not depend on whether the ideas are true” Darwin rejects this objection. He draws on many observations of animal behaviour and says that here too we can find evolution. There are differences of course, but they’re differences of degree, not of kind. This applies even to morality. He finds the origins of morality in the altruism, or group or kin altruism as we might call it, of social animals. He points out that they do help each other, and will do so even at some risk or cost to themselves, and that this could be a forerunner of morality. Darwin wrote that in 1871, and despite Darwin’s prominence, it gets neglected for a hundred years. It’s only in the 1970s, with the rise of what was then called socio-biology—what we now refer to as evolutionary psychology—that people really went back to making those sorts of comparisons, and said, ‘Look, we can see the origins of human morality in the social mammals in particular.’ There are ideas in The Descent of Man that we would today reject. Darwin refers to ‘savages’ as an in-between case between animal and human morality, for example. They’ve progressed beyond the level of non-human animals, in his view, but not up to the level of a nineteenth century Englishman. That’s right. Mill, after all, worked for the East India Company and to that extent was involved in propping up colonialism in India. Both Darwin and Mill were people of their times, and subject to some of those prejudices. What you said about Darwin deploring the idea that we interfere with evolution isn’t quite right, though. He did note that we allow the weaker members of our species to survive and reproduce, and suggests that this may be harmful to the human race, but he rejects the idea that we should harden ourselves so as not to help the weak survive. To check our sympathy in this way would, he wrote, lead to ‘deterioration in the noblest part of our nature.’"