The Human Instinct: How We Evolved to Have Reason, Consciousness, and Free Will - Hardcover

Kenneth R. Miller is professor of biology at Brown University and the critically acclaimed bestselling author of Only a Theory, Finding Darwin’s God, and The Human Instinct. He has appeared frequently on radio and television as a public advocate for evolution. In 2005 he was the lead expert witness for the victorious plaintiffs in the landmark Kitzmiller v. Dover trial, where he testified in favor of evolution and against “intelligent design.” Among his honors are the Stephen Jay Gould Prize from the Society for the Study of Evolution, the Laetare Medal from the University of Notre Dame, and the Award for Public Engagement with Science from the American Association for the Advancement of Science.

The Human Instinct Chapter 1

Grandeur

I think Charles Darwin might have seen his critics coming. Unlike most nineteenth-century works of science, On the Origin of Species is still read today. Much of that attention has been earned by the logical power and simplicity of Darwin’s argument. He begins with a chapter on variation among domestic animals and plants, something that every animal and plant breeder in the England of his time would have been familiar with. Chapter 2 points out that similar variation exists in wild species. Having established that individual members of a species vary in their characteristics, chapter 3 then describes a “struggle for existence” occurring everywhere in the natural world, producing forces that work remarkably like the hand of a breeder to shape the characteristics of every living species. At that point, the stage is set for the theory of evolution by natural selection, which he introduced by name in chapter 4. The remaining ten chapters enlarge and expand upon the evidence for this theory. The book has been called “one long argument,” and so it is. A powerful and elegant argument.

But there is another reason The Origin is not only read today, but also widely quoted. While much of the book is mired in scientific minutiae and arcane speculation, as it moves toward a conclusion, The Origin shines with a clarity—even a kind of poetry—rarely seen in a scientific document. In particular, having brought his many arguments to their logical conclusions, Darwin seems compelled to tell us what a wonderful vision of nature he has set before us:

When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Silurian system was deposited, they seem to me to become ennobled.1

And why are they “ennobled”? To Darwin, it is because living species are linked to an almost endless history of struggle and success, often against great odds. So distant is that past, so persistent are the triumphs of those shaped by natural selection, that we may look at them with pride, confident of an equally long and glorious future.

As all the living forms of life are the lineal descendants of those which lived long before the Silurian epoch, we may feel certain that the ordinary succession by generation has never once been broken, and that no cataclysm has desolated the whole world. Hence, we may look with some confidence to a secure future of equally inappreciable length. And as natural selection works solely by and for the good of each being, all corporeal and mental endowments will tend to progress towards perfection.2

Every day, in every way, they’re getting better and better—and so are we. The future is secure, and we’re getting closer to perfection. Fine words, even though most biologists today, myself included, would argue that evolution never produces “perfection.” In fact, it never even gets close. Success in the struggle for existence is all that matters, so being just good enough to get by is good enough. Always has been, always will be. But Darwin spun things differently.

As stirring as these words about perfection may have seemed to nineteenth-century readers, the final paragraph of The Origin reaches even higher. Darwin wants us to find beauty in the apparent chaos of nature, using the metaphor of a tangled bank alongside a stream to represent the creativity of the evolutionary process:

It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us.3

And finally, just in case his readers might be a bit distressed by the realizations that they are merely the products of “laws acting around us,” he assures us that there is indeed something special, something glorious about the whole process:

There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.4

It’s a stirring sentence. I have often quoted it in my own writings and lectures, and I’m not alone. But if his ideas were on such firm footing, as they clearly were, why did Darwin find it necessary to describe his vision as one of “grandeur”? I think it may have been because he recognized full well that many, if not most, of his readers would surely think otherwise. If we find our origin in the natural world by means of natural laws, then how can we possibly consider humankind as something apart from the beasts of the field, or even the slimy critters of the soil? Punch, the humor magazine, picked up on this much later with a satirical cartoon on its cover, stating “Man is but a worm.”5 Building on Darwin’s own writings, the cartoon depicted an earthworm-like creature first arising out of chaos, then morphing into a series of monkeys, next a cave man, then an English aristocrat, and finally into Darwin himself. Hardly a vision rooted in grandeur.

Darwin clearly realized that a little polishing of the human ego would go a long way toward encouraging acceptance of his ideas, and that is exactly what we see in the concluding paragraphs of The Origin. He understood that most would not find this vision “grand” and decided to do what he could to convince them otherwise. But I’m not sure this appeal to his readers to recognize the “grandeur” of evolution ever took hold. And I believe that remains the case today, even among many who fully accept the evolutionary story of our origins.

In Ian McEwan’s novel Saturday, his contemporary protagonist begins the single day of the story’s title by contemplating Darwin’s use of that very word. As Henry Perowne, a London neurosurgeon, rises, the phrase comes to him over and over again: There is grandeur in this view of life. Three times he repeats those words, and then remembers why. Last night, in the bath after a tiring day, he had skimmed a biography of Darwin sent him by his “all too literate” poet daughter, Daisy. He doesn’t remember much—he’d never actually read Darwin himself—but that phrase stuck with him. Musing to himself, he contemplates the forces that drove the great naturalist to compose the final sentence of his masterwork:

Kindly, driven, infirm Charles in all his humility, bringing on the earthworms and the planetary cycles to assist him with a farewell bow. To soften the message, he also summoned up a Creator in later editions, but his heart was never really in it. Those five hundred pages deserved only one conclusion: endless and beautiful forms of life, such as you see in a common hedgerow, including exalted beings like ourselves, arose from physical laws, from war of nature, famine, and death. This is the grandeur. And a bracing kind of consolation in the brief privilege of consciousness.6

We emerge from war, famine, and death, and all we have to show for it is the “brief privilege of consciousness”? Having rushed headlong through his medical studies and into practice, Perowne, who describes himself as not having touched a non-medical book for fifteen years, permits himself a brief contemplation of the meaning of Darwin’s work. Although a nonbeliever, it leads him to think of religion. He recalls the words of Philip Larkin, where the poet wrote that if he ever needed to “construct a religion,” he would make use of water.

Perowne, the rationalist, doesn’t hold much stock in Larkin’s answer. But he thinks to himself that if he were ever “called in” to construct a religion, instead of water,

. . . he’d make use of evolution. What better creation myth? An unimaginable sweep of time, numberless generations spawning by infinitesimal steps complex living beauty out of inert matter, driven on by the blind furies of random mutation, natural selection and environmental change, with the tragedy of forms continually dying, and lately the wonder of minds emerging and with them morality, love, art, cities—and the unprecedented bonus of this story happening to be demonstrably true.7

Demonstrably true, but nonetheless often uninspiring. As he goes about his business, Perowne watches a massive demonstration against the invasion of Iraq but is strangely detached from it by his willingness to appreciate arguments on both sides of the debate. The same profound rationality leads him to dismiss “magical realism” in literature, even though his daughter urges him otherwise. As the day wears on, a minor traffic accident followed by an attempt by the other driver at extortion places Henry and ultimately his family in danger.

In what might fairly be called the climax of the novel, Henry’s apartment is invaded and his family is held at knifepoint by Baxter, the extortionist. Perowne’s daughter is forced to strip naked, at which point Baxter notices a book of poems with the name “Daisy Perowne” inscribed on the cover. Intrigued, he demands she read one of her poems. As she seems to comply, Baxter is so taken by the beauty of the poem that he asks her to read it again—at which point it becomes clear to her father and the reader that Daisy isn’t reading one of her own poems at all. Instead, she’s recited, from memory, Matthew Arnold’s classic “Dover Beach.” For Baxter, the second reading is mesmerizing. His mind seems to wander, which leads to a distracted confrontation in which Perowne and his son are able to overpower and disable the intruders. Afterward, the family realizes that Daisy’s choice of Arnold’s poem, which she had memorized in her youth, had been their literal salvation.

McEwan, the author, clearly wanted his readers to contemplate the particular poem Daisy recited to Baxter. As if to emphasize this point, he included the full text of “Dover Beach” on two pages following the conclusion of the novel. It makes a fitting afterword to a novel that began with ironic references to Darwin’s view of the grandeur of life. The poem’s thirty-seven lines contain a deeply thoughtful and melancholy reflection on the onrush of the modern age in mid-nineteenth-century Britain. As Arnold writes:

The Sea of Faith

Was once, too, at the full, and round earth’s shore

Lay like the fields of a bright girdle furled.

But now I only hear

Its melancholy, long, withdrawing roar,

Retreating, to the breath

Of the night-wind, down the vast edges drear

And naked shingles of the world.

To Arnold, the world has changed, changed utterly. The roar of the ocean at Dover seems only to “bring the eternal note of sadness in,” and the modern age, with all its wonders and delights, “Hath really neither joy, nor love, nor light, nor certitude, nor peace, nor help for pain.” The same is surely true of the day that Henry Perowne, the successful neurosurgeon, has just endured. The disruptions of the modern age, as described in Saturday, intrude despite one’s best efforts to find certitude, joy, and peace. And that promise of grandeur seems to fade away as surely as the ebbing waves at Dover Beach.
A SCIENCE OF LIFE

Arnold’s poem mirrors much of the popular reaction to Darwin. Once the “sea of faith” was full and round the Earth. But today we see only its “long, withdrawing roar” as evolution displaces the old certainties. Arnold penned “Dover Beach” before The Origin, but he published it in 1867, well after Darwin’s book had shocked much of Victorian society. Ever since, it has been seen as emblematic of the crisis of faith brought about by the emergence of modern science. And, as McEwan’s novel demonstrates, that crisis has not abated.

Setting aside, at least for a moment, the sentiments of artistic intellectuals such as Arnold and McEwan, it’s only fair to ask whether and how such concerns have affected the larger culture. In the United States, where outright rejection of evolution is common, one might ask how this came to be. Ironically, one could make a strong argument that it was our country’s enlightened drive for universal high school education that brought it on.

Although the United States helped to pioneer free public education, the level of such schooling did not usually extend to the secondary level until the beginning of the twentieth century. Indeed, only one of my four grandparents, all born around the turn of that century, was educated past the eighth grade. But as states began to mandate higher levels of education, schools expanded and with them the demand for teachers and instructional material such as textbooks. As historian Adam R. Shapiro explains in his book, Trying Biology,8 this led New York–based textbook publishers to expand their offerings beyond the basic lessons in botany and zoology that had been part of the curriculum up to that time. Specifically, they offered new books geared to biology itself as a secondary-level discipline. These texts were skillfully marketed by local and regional sales agents, and in line with the social optimism of the times, had a distinct focus on applying scientific knowledge for the betterment of society. The title of one such text, George Hunter’s Civic Biology, reflected this trend and drew broad conclusions as to how evolutionary principles might be applied to improve society. As such, the book discussed personal hygiene, proper social behavior, and even eugenics. This, of course, was the very textbook used by substitute teacher John Scopes in Dayton, Tennessee.

Compulsory high school education appeared first mostly in urban school districts. This led to a concern that many of the instructional materials clashed with the more rural values of states such as Tennessee, where evolution was regarded as just such an “urban” value. Also, as Shapiro notes, in many states, interactions between local school districts and avaricious publishers persuaded state authorities to wrest control of textbook purchases from individual schools. This led to state oversight of instructional materials and opened the door to legislative battles over the content of textbooks, battles that persist to the present day. It was in this context that the State of Tennessee passed a law, early in 1925, leading directly to the trial of that substitute biology teacher just a few months later.

The Scopes “Monkey Trial,” held in Dayton, Tennessee, in 1925, is widely regarded as one of the key events in the social history of the United States. To many Americans, the Scopes trial represents a heroic battle in which reason and science were pitted against ignorance and superstition. The trial was loosely dramatized in the 1955 play Inherit the Wind, which has been adapted for television and motion pictures no less than four times. Evolution, of course, serves as the stand-in for enlightenment and reason in that battle. One of the authors of the play, Jerome Lawrence, made this explicit, admitting in an interview that “we used the teaching of evolution as a parable, a metaphor for any kind of mind control [ . . . ] It’s not about sci...