The Philosophical Breakfast Club

by Laura J. Snyder

  Like the members of the Philosophical Breakfast Club, Maxwell kept an eye open for practical results of his researches, especially those that could improve the lives of others. In one of his groundbreaking papers on the causes of color blindness, Maxwell reported that after he completed his experiments, he made one of his experimental subjects “a pair of spectacles, with one eye-glass red and the other green.” The subject, “Mr. X.,” was intending to wear them in order to gain the habit of discriminating red from green by the different effects on his eyes. “Though he can never acquire a sensation of red,” Maxwell explained, “he may then [be able to] discern for himself what things are red, and the mental process may become so familiar to him as to act unconsciously like a new sense.”7

  Maxwell’s work in physics followed the philosophical guidelines set by the members of the Philosophical Breakfast Club, a model that continues to shape scientific research today. Influenced very much by Whewell’s philosophy of science—as Maxwell himself admitted—and also by Herschel’s and Babbage’s, he performed a grand bit of consilience-making.8 Maxwell synthesized all observations, experiments, and equations of electricity, magnetism, and optics into a single theory, electromagnetic field theory. It was the first modern “theory of everything” in physics.

  In 1831, while moving a magnetic loop near a battery, Michael Faraday had realized that a changing magnetic field caused an electrical current. Known as electromagnetic induction, this discovery became the cornerstone of modern technology, underlying the operation of most electrical mechanisms, including the generator and the transformer. Faraday went on to explore further the connection between electricity and magnetism, finding that they were actually two manifestations of a single “electromagnetic” force. Whewell, who was then corresponding with Faraday, giving him terms for his new discoveries, recommended that he investigate the connection between magnetism and light. Faraday did so, and discovered that light shining through a transparent medium, such as glass, could be affected by the presence of a magnetic field. This suggested that there was some strong connection between magnetism and light, though Faraday himself never proved what this connection was.

  Around 1862, while lecturing at King’s College, Maxwell calculated that the speed of propagation of an electromagnetic field is approximately that of the speed of light. He considered this to be more than just a coincidence, and commented, “We can scarcely avoid the conclusion that light consists in the transverse undulations of the same medium which is the cause of electric and magnetic phenomena.”9 Working on the problem further, Maxwell showed that the calculations predicted the existence of waves of oscillating electric and magnetic fields traveling through empty space at a speed that could also be predicted from simple electrical experiments. Using the data available at the time, Maxwell predicted a velocity of 310,740,000 miles per second. In a letter to Faraday around this time, Maxwell noted that predictive success (as the members of the Philosophical Breakfast Club had also stressed) would help establish the truth of his theory.10 In his 1864 paper “A dynamical theory of the electromagnetic field,” Maxwell reported, “The agreement of the results seems to show that light and magnetism are affections of the same substance, and that light is an electromagnetic disturbance propagated through the field according to electromagnetic laws.”11 He later published his results, expressed by the famous “Maxwell equations,” in his masterful work, A Treatise on Electricity and Magnetism, in 1873.

  This incredible accomplishment was the second great unification in physics, after Newton’s universal gravitation law. From that moment on, all other classic laws or equations of these disciplines became simplified cases of Maxwell’s equations. It was, as Whewell would have said, had he still been alive, an “epoch” in the history of physics. The scientific ideal of consilience, so well applied by Maxwell, has continued to play a leading role in physics into the twenty-first century. Modern physicists have joined Maxwell’s electromagnetic force and Newton’s gravitational force with two others, the “weak” and the “strong” forces, the forces that keep atoms together. Physicists now claim that everything that happens in the universe can be explained by one or more of these four forces.

  Yet it is not enough for some. Many physicists today seek to further unify these four forces into one, a true theory of everything—a goal directly related to the criterion of consilience. Einstein was driven to derive a unified field theory that would show gravity and electromagnetism to be manifestations of one underlying principle. Einstein’s dream is the holy grail of modern physics. String theory is seen by some as the way to find it. As described by Brian Greene in The Elegant Universe, from one principle—that everything at its most microscopic level consists of vibrating strings in different combinations—“string theory” provides a single explanatory framework capable of encompassing all forces and all matter. If scientists reach this grail, they will have brought to its logical consequence the Philosophical Breakfast Club’s dreams of unifying the natural world.

  Maxwell is also known for the “Maxwell Distribution” describing the motion of gas molecules. In 1866 he formulated (independently of Ludwig Boltzmann in Austria, who was doing similar work at the same time) what is now known as the Maxwell-Boltzmann kinetic theory of gases. Maxwell approached kinetic theory, in which temperature and heat involve nothing but molecular movement, armed with Quetelet’s notion of a statistical law, which Maxwell had learned from reading Herschel’s review of a book by the Belgian astronomer and statistician. Maxwell’s distribution law gives the fraction of gas molecules moving at a specified velocity at any given temperature. Maxwell noted that the velocities of different molecules of a gas, even if equal at the start, would diverge in consequence of collisions with their neighbors. He thus employed a statistical method of treating the problem: the total number of molecules was divided into a series of groups, in which the velocities of all of the members of the group were the same within narrow limits. By taking the average velocity of each group into account, Maxwell was able to determine an important relationship between this velocity and the number of molecules in the group. This approach generalized the previously established laws of thermodynamics and explained existing observations and experiments better than they had been explained previously. It was another example of a newly consilient theory.

  Maxwell’s discoveries mark the moment when expressing the fundamental laws of nature began to require mathematical language too difficult for the nonspecialist to comprehend. John Couch Adams’s mathematical predictions of Neptune were already too difficult for many to follow in 1846; now, less than three decades later, physicists reached the point of no return. Unlike Faraday, whose understanding of the laws of electromagnetism could be expressed in terms of images of the behavior of magnetic field lines—images that were easy for him to draw and for his audiences to imagine—Maxwell found that he was forced to describe the deeper meaning of Faraday’s discoveries in the language of complex mathematical relations.12 Both his work on electromagnetic theory and on the kinetic theory of gases transformed the vision of the physical world and provided the groundwork for Einstein’s relativity theories. But because of their extreme complexity, Maxwell’s theories also contributed to severing the relationship between the general educated public and those making the newest and most important scientific discoveries.

  AND THUS, WITH the hoped-for transformation of the man of science, came some changes that the members of the Philosophical Breakfast Club had not anticipated, and would have regretted deeply. Only ten years after Whewell’s death, Maxwell himself bemoaned the fact that science was becoming overly specialized.13 No longer could a member of the Geology Section in the British Association be expected to understand, and contribute to, discussions about current research in physics or chemistry. It would soon become difficult even for a worker in one esoteric realm of physics to grasp fully what a fellow laborer in a different part of the field was doing. No longer is there a place for—or even the possibility of—
a mathematician-mineralogist-architectural historian-linguist-classicist-physicist-geologist-historian-philosopher-theologian-mountainclimbing-poet such as Whewell, or a trilingual-mathematician-chemist-physicist-astronomer-photographer-musician-translator such as Herschel. Trained in a particular science at Cambridge or elsewhere, admitted as a member to the appropriate section of an organization like the British Association, conducting experiments in that science, reading only specialized journals in the field—how can a modern scientist be expected to know, and understand, what is going on in all the sciences? The amateur—who could geologize during a vacation, and perform experiments with an electric battery in his basement room at night, while working out how to determine the geometrical properties of crystals in between examining Smith’s Prize candidates in mathematics—could follow wherever his interests led him; it was a freer, more interdisciplinary life, one with more chances for the seemingly unconnected bit of knowledge in one discipline to lead serendipitously to discoveries in another.

  Even worse, from the point of view of our four friends, was the erection of the wall between science and the humanistic fields, what C. P. Snow would later characterize as the divide between “two cultures.” In 1959, precisely one hundred years after the publication of Darwin’s Origin of Species, Snow delivered a lecture in the Senate House of Cambridge—where Whewell had invented the word scientist—in which he argued that the breakdown in communication between science and the humanities was a major stumbling block of the modern world. Although part of Snow’s point was the Cold War–specific one that the democracies needed to modernize underdeveloped countries or else the Communist countries would do so, and that more-widespread science training was necessary in the West to counter Soviet power, Snow’s essay can also be taken as making another, more timeless claim: that something has been lost, some bit of humanization in our overly technical world. When artists and writers are disengaged with science, and science ignores art and literature, culture pays a price. The sense of wonder in the natural world, so well expressed by poets and artists, is somehow lost to the scientists themselves who examine that world; and when scientists cannot express that wonder to others, even nonspecialists, fewer children will dream of leading a scientific life, and that life will continue to become more and more detached from the lives of people, and the practical problems that need solving.

  What we have lost, in a sense, is the romantic image of the man of science, the sense that nature should be grasped by men and women who are artists as well as scientists. Whewell captured this image so well in a letter to Jones about his upcoming trip to the Lake District in 1821: “You have no idea of the variety of different uses to which I shall turn a mountain. After perhaps sketching it from the bottom I shall climb to the top and measure its height by the barometer, knock off a piece of rock with a geological hammer to see what it is made of, and then evolve some quotation from Wordsworth into the still air above it.”14

  Herschel, too, described himself as an artist as well as a scientist—indeed, more of an artist than a scientist—content to “loiter on the shores of the ocean of science and pick up such shells and pebbles as take my fancy for the pleasure of arranging them and seeing them look pretty.”15 In some ways this wall between the artist and the scientist, between the admirer of the wonders of nature and the professional scientist, can be seen as being constructed, brick by brick, ever since 1833, when Coleridge stood in the very same room demanding a new word to distinguish the workers in science from the “natural philosophers,” and Whewell suggested the name scientist, “by analogy with”—and therefore separate from—“artist.” There would be justice in looking back at the members of the Philosophical Breakfast Club for guidance on how to knit the two cultures back together again—to help us find a way to bring humanity back into science, and scientific wonder back into our everyday experience of the world.

  THERE IS, in the National Portrait Gallery of London, a famous photograph of Herschel taken by his former protégée, Julia Margaret Cameron, in 1867. By this time Whewell and Jones were dead, and Babbage and Herschel were soon to follow them. Herschel’s face, grizzled and framed by white hair, is half in darkness, half in light, like the celestial bodies he had spent so much time gazing upon. He looks ahead, a bit stunned by what he seems to see. Perhaps even Herschel was surprised at how much he and his friends had accomplished: they had truly transformed science and helped create the modern world.

  ACKNOWLEDGMENTS

  I AM GRATEFUL to the many people who shared my excitement about these men and their times and who were willing to answer my queries, large and small, or to listen to my musings at crucial moments: Herbert Breger on Leibniz’s calculator; Bob Bruen on the Lucasian chair; Aaron Cobb on Babbage and Herschel’s replication of Arago’s experiment; Paul Croce on science and religion; Steffen Ducheyne on the tides; Lisa Hellerstein on math, codes, and computing; Noah Heringman on Wordsworth; Amy King and Jim Kloppenberg for introductions to other sources of information; Pam Kirk Rappaport for Annie Dillard; Claude LeBrun on math; Jim Lennox on Darwin and Asa Gray; John McCaskey on Bacon (and everything else); Ed Miller on Jones’s time in Ferring; Helen Moorwood on her Whewell relations; Eric Schliesser on Adam Smith; Jim Secord on the Great Moon Hoax; John Wolff on science and religion; and Richard Yeo for a helpful discussion during a chance meeting at the British Library.

  For aid of a more tangible kind, I appreciate Paul Gaffney for his support as chair of the Philosophy Department of St. John’s; Katalin Torok for the house and car in London; and the American Philosophical Society for the Sabbatical Fellowship in 2004, which funded my early work on Whewell’s life.

  I thank Richard Horton, Babbage Project engineer at the Science Museum in London, who generously spent a morning with me discussing Babbage’s Difference Engine Number 2, which he helped to build—even taking it out of its glass case and demonstrating it—and patiently answered my detailed questions about it months later.

  I am grateful for the efforts of my “circle of ideal readers,” who made valuable suggestions on parts of the manuscript: Lisa Hellerstein, John Hogan, Jim Lennox, Jonathan Smith, Abigail Wolff, and, especially, John McCaskey, who read the entire manuscript—in some parts, numerous drafts of it—and whose astute comments greatly improved the book. I alone am responsible, of course, for any errors or infelicities that may remain.

  For help and encouragement at the very early stages of this project, I thank Robert Friedman and Barry Strauss; to Barry I also owe the introduction to my agent, Howard Morhaim, and so I am doubly grateful to him. Howard believed in this project from the start, and was every writer’s greatest first reader: tough, patient, and optimistic. He has become more than that: a real friend. Gerry Howard at Doubleday is the publishing world’s version of a nineteenth-century polymath, and I am thankful that he chose to acquire the book. Working with my editor at Broadway Books, Vanessa Mobley, has been a writer’s dream; she has been by far the finest critical reader I’ve ever had the fortune to have, and the book (and its readers) are the beneficiaries of her expertise. I also thank Vanessa’s assistant, Jenna Ciongoli, for her help in bringing this book to press, and my excellent copyeditor, David Wade Smith.

  No project of this kind could be successful without the wisdom and assistance of librarians and archivists. I am infinitely indebted to Jonathan Smith at the Wren Library, Cambridge, with whom I have been fortunate to work for years now. I thank as well Nicola Court at the Royal Society; Jonathan Harrison and Kathryn McKee at St. John’s College, Cambridge; Katy Allen of the Science Museum’s archives in Swindon; Arvid Nelson and Stephanie Horowitz Crowe at the Babbage Collection of the University of Minnesota; David Tilsley of the Lancashire Record Office; Richard Workman of the Harry Ransom Center; Deborah Jones at the Science and Society Picture Library; and the anonymous but still appreciated librarians at the British Library, the New York Public Library, the Carnegie Library in Pittsburgh, and St. John’s University Library.

  For permission
to quote from the Whewell papers at the Wren Library, I thank the Masters and Fellows of Trinity College, Cambridge; for permission to quote from the John Herschel papers and Isaac Todhunter papers at St. John’s College, Cambridge, I thank the Masters and Fellows of the College; for permission to quote from the John Herschel papers at the Royal Society, I thank the Fellows of the Royal Society; for permission to quote from the Babbage collection, I thank the British Library; I thank the Harry Ransom Humanities Research Center, the University of Texas at Austin, for permission to quote from items in its collection.

  My greatest debt is to those friends whose love and support made it possible for me to complete this book under trying circumstances. Heartfelt thanks go to Dolores Augustine, Lucille Hartman, Lisa Hellerstein, Kevin Kennedy, Pam Kirk Rappaport, Jim Lennox, Michael Mariani, John McCaskey, Marilyn Musial Trainor, Larry Trainor, Dan Wackerman, and Abigail Wolff.

  The book is dedicated to my son, Leo, who reminds me every day how joyful the process of discovery can be, and how much wonder there is in the world.

  NOTES

  PROLOGUE: INVENTING THE SCIENTIST

  1 Quoted in Lockyer, “Presidential Address,” p. 4.

  2 On the BAAS meeting in Cambridge, see Morrell and Thackray, Gentlemen of Science: Early Years, pp. 165–75.

  3 Whewell, “Address.”