The Invention of Air Read online

  To look down from the eminence, and to see, and compare all those gradual advances in the ascent, cannot but give the greatest pleasure to those who are seated on the eminence, and who feel all the advantages of their elevated situation. And considering that we ourselves are, by no means, at the top of human science; that the mountain still ascends beyond our sight, and that we are, in fact, not much above the foot of it, a view of the manner in which the ascent has been made, cannot but animate us in our attempts to advance still higher, and suggest methods and expedients to assist us in our farther progress.

  But even if eighteenth-century Europe was still miles away from the peak, Priestley nonetheless made it clear in his History which mountaineer had reached the highest elevation to date. He devoted almost a hundred pages to Ben Franklin’s experiments and theories about electricity. On page 160 of the original printing, in a chapter devoted to Franklin’s probing of the connection between lightning and electricity, Priestley launched into the story of a curious experiment that Franklin had devised in Philadelphia fifteen years before:

  To demonstrate, in the completest manner possible, the sameness of the electric fluid with the matter of lightning, Dr. Franklin, astonishing as it must have appeared, contrived actually to bring lightning from the heavens, by means of an electrical kite, which he raised when a storm of thunder was perceived to be coming on. . . . [S]o capital a discovery as this (the greatest, perhaps, that has been made in the whole compass of philosophy, since the time of Sir Isaac Newton) cannot but give pleasure to all my readers. . . .

  The classic image of Franklin with his electrified kite, ingrained in the minds of countless American schoolchildren over the past two centuries, dates back to this paragraph from Priestley’s History. Franklin himself had only published a brief third-person account of his experiment in the Pennsylvania Gazette, without specifying that he himself had performed it. In fact, Franklin would never provide a direct account of his kite-flying experiment in any of his own published works, leading some subsequent scholars to suspect that the whole episode was a fabrication. But he willingly gave Priestley extensive details on the event. (“Dreading the ridicule which too commonly attends unsuccessful attempts in science, [Franklin] communicated his intended experiment to no body but his son, who assisted him in raising the kite.”) Priestley’s story was engineered to do more than just popularize the bold, life-threatening scientific adventures of his new friend. It was also an attempt to give Franklin partial credit for independently proving that lightning was electrical in nature. Three French scientists, inspired by Franklin’s experiments, had constructed an iron rod that successfully drew lightning from the sky in May of 1752. Priestley pointedly ends his account of Franklin’s kite with a coda: “This happened in June 1752, a month after the electricians in France had verified the same theory, but before he had heard any thing that they had done.”

  So many elements from Franklin and Priestley’s future—the folklore and popular mythology, the intellectual camaraderie, the world-changing ideas—are bound together as a first draft in the pages of the History. Franklin had helped Priestley become one of the great scientists of the age, and he supplied the source material that Priestley used to build his progressive vision of history, a model that would govern his thinking for the remainder of his days. Priestley had, in turn, created an iconic portrait of his mentor, and planted him in the Enlightenment pantheon alongside Isaac Newton. Franklin with his kite remains the defining image of the practical scientific ingenuity of the American founding fathers. And we have Joseph Priestley to thank for it.

  THE SUCCESS OF THE HISTORY and the alliance with the Honest Whigs catapulted Priestley into a new realm of influence and recognition. But it was only a preview of coming attractions. Over the next eight years, he would go on an intellectual streak of legendary proportions, making two groundbreaking discoveries, each one the sort of achievement that on its own would warrant inclusion in the pantheon of Enlightenment science. He would publish multiple papers on his electrical research, inventing new apparatuses for the creation of electrical charge and recording the first known sighting of what we now call an “oscillatory discharge,” which would eventually be crucial to the technology of radio and television. He would isolate and name ten distinct gases, now understood as some of the building blocks of Earth’s atmosphere, sparking a revolution in chemistry. Along the way, he would write more than fifty books and pamphlets on politics, education, and faith.

  And if that list doesn’t seem impressive enough: he would also invent soda water.

  Before we turn to the specifics of this extraordinary chapter in Priestley’s life, we should first consider the interpretative problem it forces us to confront: not just the what of what happened, but the why. Intellectual historians have long wrestled with the strangeness of this kind of streak. The thinker plods along, publishing erratically, making incremental progress, and then, suddenly—the flood-gates open and a thousand interesting ideas seem to pour out. It’s no mystery that there are geniuses in the world, who come into life with innate cognitive skills that are nurtured and provoked by cultural environments over time. It’s not hard to understand that these people are smarter than the rest of us, and thus tend to come up with a disproportionate share of the Big Ideas. The mystery is why, every now and again, one of these people seems to get a hot hand.

  One possibility is that the whole concept of the hot hand is an illusion, a trick of the mind that exploits our woeful skills at probability analysis. If you dispersed innovations randomly across a group of people, and placed them at random intervals as well, a few clusters would undoubtedly appear where an individual researcher would churn through a series of breakthrough ideas in a short amount of time. We’re naturally inclined to see a hot hand here, some extra dose of inspiration that triggered the streak in the first place, but in fact the streak would just be an offshoot of that random distribution, no more magical than a repeated coin toss that every now and then turns up heads ten times in a row. Two famous studies of streaks in sports—a basketball study by Stanford psychologist Amos Tversky and a baseball version conducted by the Harvard Nobel laureate Ed Purcell—found that hot hands were a figment of our imagination: the fact that a player has just made a free throw makes him no more or less likely to sink the next one. Even the humiliating nadir of the Baltimore Orioles’ 0-for-21 losing streak that began their 1988 season was securely within the range of expected outcomes, given the 200,000 major league games that have been played in the modern era. As Stephen Jay Gould put it, in an essay that widely popularized these studies: “Nothing ever happened in baseball above and beyond the frequency predicted by coin-tossing models. The longest runs of wins or losses are as long as they should be, and occur about as often as they ought to.” The one exception, Gould went on to concede, was DiMaggio’s fifty-six-game hitting streak, so far above the predicted range that, in Gould’s words, it “ranks as pure heart.”

  The question for intellectual history is whether streaks of innovation are more like the Orioles’ dismal start in ’88 or more like DiMaggio in the summer of ’41—a fantasy of misinterpreted probability or the sign of some special force at work, a “zone” that somehow lowers the barriers to discovery and understanding. One reason to suspect the latter is that, unlike free throws, ideas are clearly cumulative in nature; solving one problem often gives you a new set of conceptual tools that help you solve the next problem that presents itself. But with Priestley, the mystery is not just that he was able to hit upon so many important ideas in such a brief time frame, it’s also that those ideas were scattered across so many different fields.

  There is a parallel mystery here, one level up the chain. Human cultures have a long track record of collective hot streaks, where clusters of innovations seem to burst into flame after centuries of darkness. (We have names like “Renaissance” precisely to mark exactly how extreme the transformation is.) Priestley was a key participant in one of these cultural-phase transitions, wha
t was described self-consciously at the time, by Kant and others, as the Enlightenment, a term that embraces both the widening of political and religious possibility in eighteenth-century Europe and the extensive application of the scientific method to problems that had previously been shrouded in darkness. There were literally dozens of paradigm shifts in distinct fields during Priestley’s lifetime, watershed moments of sudden progress where new rules and frameworks of understanding emerged. Priestley alone was a transformative figure in four of them: chemistry, electricity, politics, and faith. Each paradigm shift on its own has its own internally consistent narrative that describes its path, explaining how we came to understand something like the single-fluid theory: a litany of hunches, experiments, published papers, and popularizations. But what we don’t have is a convincing theory about the system that connects all these local innovations, that causes them to self-organize into something so momentous that we have to dream up a name like the “Age of Enlightenment” to describe it. Beneath those innovations some deeper force seems to be operating, a kind of intellectual plate tectonics driving a thousand tremors on the surface. In Priestley’s mountain metaphor, it’s not so much that we are climbing the slope, but that the mountain itself is being pushed higher by the force of those immense but unseen land masses colliding. But what is that force exactly—and how can we measure it?

  You can see in those opening passages from The History and Present State of Electricity that Priestley was acutely aware of this problem; the structure of the book itself was designed, in a sense, to present that long-term progressive movement with maximum emphasis. This is a sensibility that was largely absent in the Renaissance, despite the achievements of that period; the hill-town cultures of northern Italy still imagined historical change as Fortune’s wheel: rising, falling, waxing, waning. Beginning with Descartes and Bacon, a feeling began to emerge in Western Europe that history was charting another trajectory—not an endless cycle of rise and fall, but instead a steady climb upward. Priestley’s book was an attempt to take that hunch and turn it into history.

  By the time of his death, the premise that society and science were riding a kind of permanent escalator, ascending the slope at ever-increasing speed, would be widely accepted, and the debate would turn to the nature of the engine that was driving that process. For much of the nineteenth century, the engine was dialectics—first in the abstract approach that Hegel took in his Philosophy of History, and then in the materialist rendition of Marx and Engels that famously turned Hegel “on his head.” Social and intellectual history, in this view, advanced according to the fundamental laws of dialectical progress, thesis confronting antithesis, and generating some higher-order synthesis out of that collision. The existence of this force was, for generations of thinkers, as immutable and ubiquitous as gravity itself, and yet the concept has a strange mysticism to it—even in Marx’s more grounded economic version. Its origins are as a philosophical method, a way of working through an argument to reach a more advanced understanding. It’s easy to understand why an individual logician might use the dialectical method to construct a proof. But why should uncoordinated, collective behavior follow dialectical patterns? Cultural change needn’t necessarily take that particular shape; it’s more intuitive, in fact, to think that it would mimic the characteristic patterns of other systems: waves, for instance, or epidemics, or information networks.

  What Marx did grasp, more clearly than any thinker before him, was that the proper interpretative scale for understanding change and progress is larger and deeper than that of the individual human life, yet at the same time is grounded in the material world. You couldn’t attribute change exclusively to exceptional people, and you couldn’t attribute it to some external and nebulous spirit, the way Hegel had done. There were great thinkers and leaders and visionaries, to be sure—Marx held Hegel up as one of them, to a fault probably—but that “great man” view of historical change exposed only a small slice of the full story, because the creation and spread of new ideas and new ways of living are shaped by forces both greater and smaller than individual humans. Marx identified three new primary macro processes that deserved to be included in the narrative: the class struggle, the evolution of capital itself, and technological innovations. They were all, for different reasons, enormously valuable contributions to the project of making sense of historical change. And they were all fundamentally correct, at least in their contention that class identity, capital, and technological acceleration would be prime movers in the coming centuries, and that each one had an independent life, outside the direct control of human decision-makers. Humans made the steam engine, but the steam engine ended up remaking humanity, in ways that the original inventors never anticipated.

  The contemporary view of intellectual progress is dominated by one book: Thomas Kuhn’s The Structure of Scientific Revolutions, published in 1962, from which the now conventional terms “paradigm” and “paradigm shift” originate. By some measures, Kuhn’s book was the most cited text in the last quarter of the twentieth century, and it regularly ranks among the most influential books of the entire century. In Revolutions, Kuhn set out to dismantle the idea that scientific progress happens in a linear fashion, as a series of indisputable facts unearthed one after another, each breakthrough another definitive step toward absolute truth. (Kuhn calls this the “development-by-accumulation” model.) Instead, he explained, “normal” science works within an established paradigm: a set of rules and conventions that govern the definition of terms, the collection of data, and the boundaries of inquiry. But over time, anomalies appear inside the paradigm: data that can’t be explained, questions that can’t be answered using the tools of the existing model. At that point, certain adventurous researchers begin practicing what Kuhn called “revolutionary science,” reaching outside the boundaries of the old paradigm, inventing new rules and conventions that eventually cause the old paradigm to collapse. The classic case study for the concept of a paradigm shift is the Copernican revolution in astronomy, but in actual fact, the first extended story that Kuhn tells in The Structure of Scientific Revolutions is the paradigm shift in chemistry that took place in the 1770s, led by the revolutionary science of Joseph Priestley.

  While Kuhn’s system placed the scientist squarely at the center of intellectual change, it made an essential break from the folklore of individual genius that Priestley had himself questioned two centuries before. Kuhn demonstrated convincingly that science was not a straightforward pursuit of universal truth, the genius suddenly discovering new facts about the world by sheer force of intellect. Instead, innovations in science came out of a complicated play among insight, empirical study, and the conventions of a given paradigm. The facts themselves were bounded, and in part created, by the cultural prescriptions of the current model. The trouble with Kuhn’s system, however, came from its own, self-professed conceptual boundaries. “Aside from occasional brief asides,” Kuhn explained in the preface, “I have said nothing about the role of technological advance or of external social, economic, and intellectual conditions in the development of the sciences.” In Kuhn’s analysis, change happens because anomalies appear inside the rules and expectations of normal science. External changes—in technology, society, politics—do not appear as factors in this schema. Revolutionary science happens inside the lab, isolated from the tumult of the external world. But what happens when a scientific paradigm shift coincides with comparable revolutions in the structure of human society or religious belief? Surely there are causal links that connect them, particularly when one man lies at the center of so many simultaneous revolutions.

  Is there a better organizing principle, a better metaphor for making sense of conceptual revolutions like those that Priestley helped bring about? One might be a twentieth-century concept that neither Priestley nor Marx had available to them, and which was still a new idea for Thomas Kuhn in 1962: the ecosystem. Ecosystem theory has changed our view of the planet in countless ways, but as an intellect
ual model it has one defining characteristic: it is a “long zoom” science, one that jumps from scale to scale, and from discipline to discipline, to explain its object of study: from the microbiology of bacteria, to the cross-species flux of nutrient cycling, to the global patterns of weather systems, all the way out to the physics that explains how solar energy collides with the Earth’s atmosphere. This is what ecosystem science looks like in practice:

  This is the Bretherton diagram, prepared by a committee of scholars associated with NASA in the mid-eighties. It attempts to show the main dynamics of global ecosystems theory, the multidisciplinary field that goes by the name Earth System Science. The diagram looks formidable to the untrained eye, but it looks even more formidable to the trained eye, because the trained eye sees in a flash how many distinct disciplines are yoked together in this densely interconnected system. Economists, microbiologists, atmospheric physicists, marine biologists, geologists, urban historians, chemists: these are intellectual clans that historically have not spoken the same language, much less shared a table at the same coffeehouse. And yet there they are—connected, interdependent—on the Bretherton diagram. To make sense of the world system, they have had to learn to speak a common language.