Science is not a list of empirical facts. Scientists are immersed in the ethereal medium of information, including the truths of mathematics, the logic of their theories, and the values that guide their enterprise. Nor, for its part, has philosophy ever confined itself to a ghostly realm of pure ideas that float free of the physical universe. The Enlightenment philosophers in particular interwove their conceptual arguments with hypotheses about perception, cognition, emotion, and sociality. (Hume’s analysis of the nature of causality, to take just one example, took off from his insights about the psychology of causality, and Kant was, among other things, a prescient cognitive psychologist.)16 Today most philosophers (at least in the analytic or Anglo-American tradition) subscribe to naturalism, the position that “reality is exhausted by nature, containing nothing ‘supernatural,’ and that the scientific method should be used to investigate all areas of reality, including the ‘human spirit.’”17 Science, in the modern conception, is of a piece with philosophy and with reason itself.
What, then, distinguishes science from other exercises of reason? It certainly isn’t “the scientific method,” a term that is taught to schoolchildren but that never passes the lips of a scientist. Scientists use whichever methods help them understand the world: drudgelike tabulation of data, experimental derring-do, flights of theoretical fancy, elegant mathematical modeling, kludgy computer simulation, sweeping verbal narrative.18 All the methods are pressed into the service of two ideals, and it is these ideals that advocates of science want to export to the rest of intellectual life.
The first is that the world is intelligible. The phenomena we experience may be explained by principles that are deeper than the phenomena themselves. That’s why scientists laugh at the Theory of the Brontosaurus from the dinosaur expert on Monty Python’s Flying Circus: “All brontosauruses are thin at one end, much much thicker in the middle, and then thin again at the far end”—the “theory” is just a description of how things are, not an explanation of why they are the way they are. The principles making up an explanation may in turn be explained by still deeper principles, and so on. (As David Deutsch put it, “We are always at the beginning of infinity.”) In making sense of our world, there should be few occasions on which we are forced to concede, “It just is” or “It’s magic” or “Because I said so.” The commitment to intelligibility is not a matter of raw faith, but progressively validates itself as more of the world becomes explicable in scientific terms. The processes of life, for example, used to be attributed to a mysterious élan vital; now we know they are powered by chemical and physical reactions among complex molecules.
Demonizers of scientism often confuse intelligibility with a sin called reductionism, the analysis of a complex system into simpler elements, or, according to the accusation, nothing but simpler elements. In fact, to explain a complex happening in terms of deeper principles is not to discard its richness. Patterns emerge at one level of analysis that are not reducible to their components at a lower level. Though World War I consisted of matter in motion, no one would try to explain World War I in the language of physics, chemistry, and biology as opposed to the more perspicuous language of the perceptions and goals of leaders in 1914 Europe. At the same time, a curious person can legitimately ask why human minds are apt to have such perceptions and goals, including the tribalism, overconfidence, mutual fear, and culture of honor that fell into a deadly combination at that historical moment.
The second ideal is that we must allow the world to tell us whether our ideas about it are correct. The traditional causes of belief—faith, revelation, dogma, authority, charisma, conventional wisdom, hermeneutic parsing of texts, the glow of subjective certainty—are generators of error, and should be dismissed as sources of knowledge. Instead our beliefs about empirical propositions should be calibrated by their fit to the world. When scientists are pressed to explain how they do this, they usually reach for Karl Popper’s model of conjecture and refutation, in which a scientific theory may be falsified by empirical tests but is never confirmed. In reality, science doesn’t much look like skeet shooting, with a succession of hypotheses launched into the air like clay pigeons and shot to smithereens. It looks more like Bayesian reasoning (the logic used by the superforecasters we met in the preceding chapter). A theory is granted a prior degree of credence, based on its consistency with everything else we know. That level of credence is then incremented or decremented according to how likely an empirical observation would be if the theory is true, compared with how likely it would be if the theory is false.19 Regardless of whether Popper or Bayes has the better account, a scientist’s degree of belief in a theory depends on its consistency with empirical evidence. Any movement that calls itself “scientific” but fails to nurture opportunities for the testing of its own beliefs (most obviously when it murders or imprisons the people who disagree with it) is not a scientific movement.
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Many people are willing to credit science with giving us handy drugs and gadgets and even with explaining how physical stuff works. But they draw the line at what truly matters to us as human beings: the deep questions about who we are, where we came from, and how we define the meaning and purpose of our lives. That is the traditional territory of religion, and its defenders tend to be the most excitable critics of scientism. They are apt to endorse the partition plan proposed by the paleontologist and science writer Stephen Jay Gould in his book Rocks of Ages, according to which the proper concerns of science and religion belong to “non-overlapping magisteria.” Science gets the empirical universe; religion gets the questions of morality, meaning, and value.
But this entente unravels as soon as you begin to examine it. The moral worldview of any scientifically literate person—one who is not blinkered by fundamentalism—requires a clean break from religious conceptions of meaning and value.
To begin with, the findings of science imply that the belief systems of all the world’s traditional religions and cultures—their theories of the genesis of the world, life, humans, and societies—are factually mistaken. We know, but our ancestors did not, that humans belong to a single species of African primate that developed agriculture, government, and writing late in its history. We know that our species is a tiny twig of a genealogical tree that embraces all living things and that emerged from prebiotic chemicals almost four billion years ago. We know that we live on a planet that revolves around one of a hundred billion stars in our galaxy, which is one of a hundred billion galaxies in a 13.8-billion-year-old universe, possibly one of a vast number of universes. We know that our intuitions about space, time, matter, and causation are incommensurable with the nature of reality on scales that are very large and very small. We know that the laws governing the physical world (including accidents, disease, and other misfortunes) have no goals that pertain to human well-being. There is no such thing as fate, providence, karma, spells, curses, augury, divine retribution, or answered prayers—though the discrepancy between the laws of probability and the workings of cognition may explain why people believe there are. And we know that we did not always know these things, that the beloved convictions of every time and culture may be decisively falsified, doubtless including many we hold today.
In other words, the worldview that guides the moral and spiritual values of a knowledgeable person today is the worldview given to us by science. Though the scientific facts do not by themselves dictate values, they certainly hem in the possibilities. By stripping ecclesiastical authority of its credibility on factual matters, they cast doubt on its claims to certitude in matters of morality. The scientific refutation of the theory of vengeful gods and occult forces undermines practices such as human sacrifice, witch hunts, faith healing, trial by ordeal, and the persecution of heretics. By exposing the absence of purpose in the laws governing the universe, science forces us to take responsibility for the welfare of ourselves, our species, and our planet. For the same reason, it undercuts any moral or political syst
em based on mystical forces, quests, destinies, dialectics, struggles, or messianic ages. And in combination with a few unexceptionable convictions—that all of us value our own welfare, and that we are social beings who impinge on each other and can negotiate codes of conduct—the scientific facts militate toward a defensible morality, namely principles that maximize the flourishing of humans and other sentient beings. This humanism (chapter 23), which is inextricable from a scientific understanding of the world, is becoming the de facto morality of modern democracies, international organizations, and liberalizing religions, and its unfulfilled promises define the moral imperatives we face today.
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Though science is increasingly and beneficially embedded in our material, moral, and intellectual lives, many of our cultural institutions cultivate a philistine indifference to science that shades into contempt. Intellectual magazines that are ostensibly dedicated to ideas confine themselves to politics and the arts, with scant attention to new ideas emerging from science, with the exception of politicized issues like climate change (and regular attacks on scientism).20 Still worse is the treatment of science in the liberal arts curricula of many universities. Students can graduate with a trifling exposure to science, and what they do learn is often designed to poison them against it.
The most commonly assigned book on science in modern universities (aside from a popular biology textbook) is Thomas Kuhn’s The Structure of Scientific Revolutions.21 That 1962 classic is commonly interpreted as showing that science does not converge on the truth but merely busies itself with solving puzzles before flipping to some new paradigm which renders its previous theories obsolete, indeed, unintelligible.22 Though Kuhn himself later disavowed this nihilist interpretation, it has become the conventional wisdom within the Second Culture. A critic from a major intellectual magazine once explained to me that the art world no longer considers whether works of art are “beautiful” for the same reason that scientists no longer consider whether theories are “true.” He seemed genuinely surprised when I corrected him.
The historian of science David Wootton has remarked on the mores of his own field: “In the years since Snow’s lecture the two-cultures problem has deepened; history of science, far from serving as a bridge between the arts and sciences, nowadays offers the scientists a picture of themselves that most of them cannot recognize.”23 That is because many historians of science consider it naïve to treat science as the pursuit of true explanations of the world. The result is like a report of a basketball game by a dance critic who is not allowed to say that the players are trying to throw the ball through the hoop. I once sat through a lecture on the semiotics of neuroimaging at which a historian of science deconstructed a series of dynamic 3-D multicolor images of the brain, volubly explaining how “that ostensibly neutral and naturalizing scientific gaze encourages particular kinds of selves who are then amenable to certain political agendas, shifting position from the neuro(psychological) object toward the external observatory position,” and so on—any explanation but the bloody obvious one, namely that the images make it easier to see what’s going on in the brain.24 Many scholars in “science studies” devote their careers to recondite analyses of how the whole institution is just a pretext for oppression. An example is this scholarly contribution to the world’s most pressing challenge:
Glaciers, Gender, and Science: A Feminist Glaciology Framework for Global Environmental Change Research
Glaciers are key icons of climate change and global environmental change. However, the relationships among gender, science, and glaciers—particularly related to epistemological questions about the production of glaciological knowledge—remain understudied. This paper thus proposes a feminist glaciology framework with four key components: (1) knowledge producers; (2) gendered science and knowledge; (3) systems of scientific domination; and (4) alternative representations of glaciers. Merging feminist postcolonial science studies and feminist political ecology, the feminist glaciology framework generates robust analysis of gender, power, and epistemologies in dynamic social-ecological systems, thereby leading to more just and equitable science and human-ice interactions.25
More insidious than the ferreting out of ever more cryptic forms of racism and sexism is a demonization campaign that impugns science (together with reason and other Enlightenment values) for crimes that are as old as civilization, including racism, slavery, conquest, and genocide. This was a major theme of the influential Critical Theory of the Frankfurt School, the quasi-Marxist movement originated by Theodor Adorno and Max Horkheimer, who proclaimed that “the fully enlightened earth radiates disaster triumphant.”26 It also figures in the works of postmodernist theorists such as Michel Foucault, who argued that the Holocaust was the inevitable culmination of a “bio-politics” that began with the Enlightenment, when science and rational governance exerted increasing power over people’s lives.27 In a similar vein, the sociologist Zygmunt Bauman blamed the Holocaust on the Enlightenment ideal to “remake the society, force it to conform to an overall, scientifically conceived plan.”28 In this twisted narrative, the Nazis themselves are let off the hook (“It’s modernity’s fault!”). So is the Nazis’ rabidly counter-Enlightenment ideology, which despised the degenerate liberal bourgeois worship of reason and progress and embraced an organic, pagan vitality which drove the struggle between races. Though Critical Theory and postmodernism avoid “scientistic” methods such as quantification and systematic chronology, the facts suggest they have the history backwards. Genocide and autocracy were ubiquitous in premodern times, and they decreased, not increased, as science and liberal Enlightenment values became increasingly influential after World War II.29
To be sure, science has often been pressed into the support of deplorable political movements. It is essential, of course, to understand this history, and legitimate to pass judgment on scientists for their roles in it, just like any historical figures. Yet the qualities that we prize in humanities scholars—context, nuance, historical depth—often leave them when the opportunity arises to prosecute a campaign against their academic rivals. Science is commonly blamed for intellectual movements that had a pseudoscientific patina, though the historical roots of those movements ran deep and wide.
“Scientific racism,” the theory that races fall into an evolutionary hierarchy of mental sophistication with Northern Europeans at the top, is a prime example. It was popular in the decades flanking the turn of the 20th century, apparently supported by craniometry and mental testing, before being discredited in the middle of the 20th century by better science and by the horrors of Nazism. Yet to pin ideological racism on science, in particular on the theory of evolution, is bad intellectual history. Racist beliefs have been omnipresent across history and regions of the world. Slavery has been practiced by every civilization, and was commonly rationalized by the belief that enslaved peoples were inherently suited to servitude, often by God’s design.30 Statements from ancient Greek and medieval Arab writers about the biological inferiority of Africans would curdle your blood, and Cicero’s opinion of Britons was not much more charitable.31
More to the point, the intellectualized racism that infected the West in the 19th century was the brainchild not of science but of the humanities: history, philology, classics, and mythology. In 1853 Arthur de Gobineau, a fiction writer and amateur historian, published his cockamamie theory that a race of virile white men, the Aryans, spilled out of an ancient homeland and spread a heroic warrior civilization across Eurasia, diverging into the Persians, Hittites, Homeric Greeks, and Vedic Hindus, and later into the Vikings, Goths, and other Germanic tribes. (The speck of reality in this story is that these tribes spoke languages that fell into a single family, Indo-European.) Everything went downhill when the Aryans interbred with inferior conquered peoples, diluting their greatness and causing them to degenerate into the effete, decadent, soulless, bourgeois, commercial cultures that the Romantics were always whinging about. It was a small step t
o fuse this fairy tale with German Romantic nationalism and anti-Semitism: the Teutonic Volk were the heirs of the Aryans, the Jews a mongrel race of Asiatics. Gobineau’s ideas were eaten up by Richard Wagner (whose operas were held to be re-creations of the original Aryan myths) and by Wagner’s son-in-law Houston Stewart Chamberlain (a philosopher who wrote that Jews polluted Teutonic civilization with capitalism, liberal humanism, and sterile science). From them the ideas reached Hitler, who called Chamberlain his “spiritual father.”32
Science played little role in this chain of influence. Pointedly, Gobineau, Chamberlain, and Hitler rejected Darwin’s theory of evolution, particularly the idea that all humans had gradually evolved from apes, which was incompatible with their Romantic theory of race and with the older folk and religious notions from which it emerged. According to these widespread beliefs, races were separate species; they were fitted to civilizations with different levels of sophistication; and they would degenerate if they mixed. Darwin argued that humans are closely related members of a single species with a common ancestry, that all peoples have “savage” origins, that the mental capacities of all races are virtually the same, and that the races blend into one another with no harm from interbreeding.33 The historian Robert Richards, who carefully traced Hitler’s influences, ended a chapter entitled “Was Hitler a Darwinian?” (a common claim among creationists) with “The only reasonable answer to the question . . . is a very loud and unequivocal No!”34
Like “scientific racism,” the movement called Social Darwinism is often tendentiously attributed to science. When the concept of evolution became famous in the late 19th and early 20th centuries, it turned into an inkblot test that a diverse assortment of political and intellectual movements saw as vindicating their agendas. Everyone wanted to believe that their vision of struggle, progress, and the good life was nature’s way.35 One of these movements was retroactively dubbed social Darwinism, though it was advocated not by Darwin but by Herbert Spencer, who laid it out in 1851, eight years before the publication of The Origin of Species. Spencer did not believe in random mutation and natural selection; he believed in a Lamarckian process in which the struggle for existence impelled organisms to strive toward feats of greater complexity and adaptation, which they passed on to later generations. Spencer thought that this progressive force was best left unimpeded, and so he argued against social welfare and government regulation that would only prolong the doomed lives of weaker individuals and groups. His political philosophy, an early form of libertarianism, was picked up by robber barons, advocates of laissez-faire economics, and opponents of social spending. Because those ideas had a right-wing flavor, left-wing writers misapplied the term social Darwinism to other ideas with a right-wing flavor, such as imperialism and eugenics, even though Spencer was dead-set against such government activism.36 More recently the term has been used as a weapon against any application of evolution to the understanding of human beings.37 So despite its etymology, the term has nothing to do with Darwin or evolutionary biology, and is now an almost meaningless term of abuse.