A survival guide to the
misinformation
age
scientific habits of mind
David J. Helfand
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A Walk in the Park Would you rather learn about stellar nucleosynthesis or go for a walk in the park?
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f I were to rank all of the questions I have asked in my thirty-eight years of teaching, from easiest to hardest, this would probably take the top spot. It was the first perfect spring day in New York—68 degrees under a cloudless cerulean sky with a barely perceptible breeze flitting in off the Hudson River. My class of seventy Columbia College students had torn themselves away from an early afternoon idyll on the lawn and reluctantly slid into the hard wooden seats of my air-conditioned, artificially lit lecture hall at the appointed time of 2:40 p.m. My planned lecture on how the stars cook up the atoms that compose our bones and flesh could not compete with my tempting—and most unexpected—offer. But there was a catch I told them. If we went for a walk in the park, they would have to hear how I experienced the walk—as a scientist. They were undeterred; the vote for walking was unanimous. I led them down a flight of stairs and out through the loading dock onto 120th Street into the shadow of Pupin Labs. Why into the shadow? Because we were at 40.7 degrees north latitude and the Manhattan street grid runs1 (not quite) east–west. The angle of the Sun above the horizon at
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2:40 p.m. on a spring day is insufficient to clear the thirteen-story2 building we had just exited. “What do you feel on your face?” I asked. After a confused silence, one student said, “It feels nice.” “The reason it’s nice,” I replied, “is because the air molecules— nitrogen, oxygen, and other trace constituents—are moving at about 450 meters per second today and are colliding with your skin molecules billions of times per second. These collisions trigger protein interactions in the temperature-sensing nerve cells of your skin, which in turn send an electrical signal to your thalamus, informing your prefrontal cortex that this is a copacetic environment to hang out in—that is, it’s pleasantly warm out here.” If some had thoughts of returning to stellar nucleosynthesis, they didn’t let on, so we proceeded west on 120th and into Riverside Park. Along the way, I solved the mystery of why the sky is blue (no, it is not a reflection of the color of the ocean—have you ever put seawater in a glass jar and discovered it has an azure hue?), why the pavement felt warmer than the air, why the Sun’s disk could be covered by a fingernail held at arm’s length, and why the paving stones of the park’s sidewalk are hexagonal in shape. As we entered a wooded area of the park, I made an offhand comment that all the daffodils emerging from the leaf litter were a gift from the Dutch government, an offering of solace for a wounded city after the 9/11 attack. “What daffodils?” “Where?” I will admit the bulbs had yet to flower, but the unmistakable, straight green shafts were all around us. Sadly, few, if any, of the students recognized that a glorious carpet of yellow would grace this glen in a few days. They don’t need a physicist to explain the subtleties of the unseen world around them, I thought; they need to start by regressing fifteen years or so, back to when they were curious about every aspect of the world and surely would have asked, “What are all those big fat blades of grass, Daddy?”
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What are those big blades? Why are they so fat? Where do they come from? All questions one would expect from a five-year-old on a walk through the park. My etymological dictionary says these words—what, why, and where—come from Old English, Saxon, Proto-German, and Norse. I wonder, however, about their earlier origins and their relationship to the whaaa sounds that children make long before they can speak. It is an easy, natural sound—little more than an exhalation of breath, and much more natural than the voiced alveolar lateral continuant “l” followed by the long vowel phoneme “i” and the aspirated “k” that form “like,” an utterance many eighteen-year-olds seem to feel is required between every fourth word in a sentence. I do often wish they’d go back to “why.” It is not the word choices that concerned me, however, as much as the disconnection from the natural world. I am not a fan of the proliferating number of “disorders” that we are told now afflict us, but the first twothirds of the term nature-deficit disorder3 seemed appropriate. How could they have lived eighteen years and never noticed those straight, thick blades as the harbingers of spring? But more importantly, where had their curiosity gone? Why is the sky blue, and why is it bright all over when the Sun just shines from one direction? Why does one’s cheek feel warmer in the Sun than in the shade? Why are we enjoying this walk in the park more than the lecture on nucleosynthesis? Why. It’s such a satisfying word to utter and such a visceral pleasure when understanding emerges with the answer. The light from the sky opposite the Sun is still sunlight; it has just scattered off the molecules of air in such a way that these rays precisely target your pupil and no one else’s. The wavelength of blue light is optimally tuned for this scattering, whereas the red, yellow, and green light passes directly through the atmosphere and thus appears to come only from the direction of the Sun— except when the Sun is near the horizon and the path the light must travel through the atmosphere is much longer, so that even some of the red and yellow light is scattered sideways, creating a memorable sunset (we’ll discuss sunsets further in chapter 5). 9
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The sunlight warms your cheek because, having been created through the fusion of protons in the Sun’s core and having struggled 100,000 years to reach its surface, this light finally broke free and, after traveling in a perfectly straight line for eight minutes and nineteen seconds,4 was absorbed by the molecules of your skin, which upped the tempo of their jiggling, a jiggling that was recorded in your brain as warmth. From protons fusing before civilization emerged to your glowing cheek today—it’s a beautiful and compelling story. I know—not everyone sees it this way. Consider, for example, these famous lines from British Romantic poet John Keats’s 1820 narrative poem “Lamia”: Do not all charms fly At the mere touch of cold philosophy? There was an awe-full rainbow once in heaven: We know her woof, her texture; she is given In the dull catalogue of common things. Philosophy will clip an Angel’s wings, Conquer all mysteries by rule and line, Empty the haunted air, and gnomèd mine— Unweave a rainbow, as it erewhile made The tender-person’d Lamia melt into a shade.5
We are told by Margaret Robertson, a Keats scholar, that the damnation of this “cold philosophy”—such as “unweav[ing] the rainbow” by explaining it as light refracted in water droplets—is not to be taken as Keats’s own view. Rather, it is the message of his allegorical poem that “it is fatal to attempt to separate the sensuous and emotional life from the life of reason.”6 Perhaps, but I am unconvinced. That “all charms fly” under the onslaught of scientific reasoning was a common theme of the Romantic period. William Blake’s famous monotype of Isaac Newton exudes a horrified rejection of the scientific mind that is
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expressed directly in Blake’s aphorism: “Art is the tree of life. Science is the tree of death.” The following poem by Edgar Allan Poe, “Sonnet—To Science,”7 written in 1829 when Poe was twenty years old, is said to have been inspired by Keats’s lines: Science! true daughter of Old Time thou art! Who alterest all things with thy peering eyes. Why preyest thou thus upon the poet’s heart, Vulture, whose wings are dull realities? How should he love thee? or how deem thee wise, Who wouldst not leave him in his wandering To seek for treasure in the jewelled skies, Albeit he soared with an undaunted wing? Hast thou not dragged Diana from her car? And driven the Hamadryad from the wood To seek a shelter in some happier star? Hast thou not torn the Naiad from her flood, The Elfin from the green grass, and from me The summer dream beneath the tamarind tree?
I respectfully disagree with this Romantic view, so much in the ascendancy today. The wood and water nymphs Poe mourns (the Hamadryad and Naiad, respectively) may indeed be gone. Diana (the Moon), we now know, is not a radiant goddess but a globe of rock that was sheared off from the surface of the newly forming Earth 4.5 billion years ago and that keeps a regular appointment in the sky each night because it is constrained to roll around inside an imaginary bowl created by a subtle warping of spacetime induced by the presence of the nearby Earth. I don’t find this a “dull reality” but a magnificent triumph of human curiosity, imagination, and analytical power. This debate is not just a matter of differing tastes, however; it is now an existential matter for our species. 11
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At the time Keats’s “Lamia” was published, the world population had just exceeded one billion. Life expectancy in Europe and the United States was approximately thirty-eight years. It has doubled since, and the global population has increased more than sevenfold. It took roughly 150,000 years for Homo sapiens to generate a worldwide population of one billion; the last billion were added in just twelve years.8 We have insinuated ourselves into almost every ecological niche available on the planet—regardless of whether we complement the diversity of existing life in each niche or not. We are using the demonstrably finite resources of the Earth at a manifestly unsustainable rate and are fundamentally altering the chemistry of the atmosphere and the oceans in a manner that is changing the energy balance of the planet. A simple, quantitative estimate of our impact is instructive. An animal’s basal metabolic rate is the sum of the energy consumed by the organism while it is at rest—the total energy required to maintain its body temperature and keep all its vital systems humming along. For an adult human this is roughly 100 watts. A watt is a measure of power—the rate at which energy is used. To stay alive, a person burns energy at the same rate as a 100-watt light bulb. All other animals, from cockroaches to elephants, consume energy and produce waste equivalent to their individual basal metabolic rates. But humans are uniquely clever. We also use energy to ease our travel, communicate across vast distances, alter the temperature of our environments, and manufacture toys to entertain ourselves. In fact, on average, North Americans use energy not at the 100-watt rate of their hunter– gatherer ancestors but at 100 times this rate: 10,000 watts. As the climatologist Richard Alley9 puts it, we each employ the equivalent of 100 serfs, each of whom consumes his or her 100 watts and produces the concomitant waste—at roughly 1.5 pounds per day, that’s 55,000 pounds per year. If you want to start digging the latrine, it needs to be 10 feet by 10 feet by 9 feet deep—per person per year.
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In fact, Alley notes that roughly 85 percent of these “serfs” come from fossil fuels that were created over a few hundred million years of the planet’s evolution and that we are consuming over a few hundred years, i.e., a million times faster than Nature produced them. Contrary to various alarmist predictions, there is plenty of fossil fuel left to last for centuries at rates of consumption even greater than today’s. But we cannot escape the waste; its impact is profound. Indeed, geologists, whose job it is to keep track of such things, have noted the recent transition to a new geologic era, the Anthropocene, in which the Earth’s geological, chemical, and biological systems are dominated by one species: Homo sapiens. Poe’s wood nymphs will not help us escape from this situation, nor will Diana ride to the rescue. Likewise, an abundance of “clean” natural gas will not halt global warming, homeopathy will not cure cancer, and abjuring vaccines will not eliminate autism. No aliens, hiding in a comet’s tail, will swoop down to save us. Only human imagination and ingenuity, channeled by the systematic and skeptical curiosity we call science, provide a viable path forward for our species. This book is meant to be both a warning and a celebration. First, the warning: with mass media, entire political classes, and a general public largely ignorant of, or hostile to, science, our civilization cannot survive in its current form. This is not mere opinion but a statement of fact. How our civilization will change is a matter of speculation that I will largely eschew, but most of the plausible scenarios I can see unfolding in the near future are not pretty. As important, however, is the celebration: the following chapters are written to share and, yes, to celebrate the illuminating habits of mind that characterize the enterprise we call science. This enterprise melds the marvelous natural curiosity of a five-year-old with the impressive reasoning power of the adult mind. It is a highly social enterprise, a highly creative enterprise and, William Blake notwithstanding, a life-affirming enterprise. Adopting these habits of mind opens up worlds both unseen and unseeable to understanding. It allows us to read the history of the deep 13
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past and to predict the future. It provides us with context: our “pale blue dot” is but one of eight planets and a few dozen moons orbiting one of a hundred billion stars (many of which, we now know, also have planets) that make up the Milky Way, one of a hundred billion galaxies in our visible corner of the universe. That, far more than a “rainbow in heaven,” is awe-full—it inspires awe. Perhaps most importantly, science allows us to transcend our evolutionary heritage by recognizing that the quick responses and “common sense” produced by a brain shaped over hundreds of millennia of hominid evolution in small hunter–gatherer groups are highly inappropriate on a human-dominated planet. Albert Einstein reportedly said this of common sense: “It is that layer of prejudices laid down in the mind prior to the age of eighteen.” Either we abandon those prejudices or the Anthropocene will end nearly as abruptly as did the dinosaur’s Cretaceous era—and without the assistance of an asteroid. I should be clear. Life on Earth will not be extinguished by our folly. It will change and adapt to the new conditions we create, as it has changed innumerable times over the 3.8 billion years since it emerged in sufficient profusion to leave a record. The Earth will continue to orbit the Sun, and the Moon will still roll around in its space-time dimple for another six billion years or so until the Sun begins to die. It is only if we have affection for our kind, the species we named Homo sapiens, that we must adopt scientific habits of mind and relegate the wood nymphs to their proper place—as entertaining fantasies produced by our fertile imaginations but wholly irrelevant to the operation of the universe. Homo sapiens means “wise man.” Our behavior in the coming century will determine whether this is apt nomenclature.
*** By the scheduled end of my class, eighty minutes after having left the lecture hall, we made it to 86th Street. We had discussed why the Hudson
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River is actually a fjord and had adduced not only the presence of the glacier that helped carve it but also the direction from which it ground its way forward by studying the striations in the Manhattan schist outcrops of the park. Later, plotting this direction on a map of the area, it was obvious that the lines of motion were precisely perpendicular to the orientation of Long Island, tying in this 100-mile-long mound of glacial rubble directly to the last great force that shaped the New York City landscape before men with pile drivers arrived a century ago. We discussed how the oldest trees in the park held a record of the temperature and humidity over the last century and a half in the isotopic composition of their annual rings and why the crocus blossoms look very different to us than to a bee whose sensitivity to ultraviolet light gives it a more richly variegated view,10 as well as helping it to navigate by the polarization angle of the scattered sunlight that comprises the blue sky. Before I let them go, I made my pitch for science—not as a course one has to take to fulfill a distribution requirement but as a way of greatly enriching one’s view of the world. Seeing a flower as a carefully programmed array of molecules whose subtle structural differences mean that they absorb and reflect different wavelengths of light—including some only their pollinators can detect—deepens the aesthetic experience of seeing the flower. And understanding that “seeing” is a passive activity in which packets of electromagnetic energy bounce off a petal in all directions, with only a tiny fraction heading in a perfectly straight line for the little black dot in the middle of your eye. There, they pass through, focused by a transparent lens, and are absorbed by one of three special molecules tuned to red, green, and blue light such that they can induce a set of electrochemical signals that travel at ~10 meters per second along the optic nerve to the primary visual cortex at the back of your head and thence on to a dozen other cortical substations to create the vision of a crocus blossom (whose name—if you know it—can be dredged up from the brain’s word storage area)—that’s all pretty magical, too. I’m sure not all of them bought it . . . my hope is some did. And we did get back to stellar nucleosynthesis in the next class. 15
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