Newton and the Counterfeiter (5 page)

As Book Three opens, gravity at last takes over the entire narrative. Once again, Newton begins with the foundational claims of his investigation. Most important, he states what can be seen as the fundamental axiom of science: that the properties of objects that can be observed on earth must be assumed to be properties of bodies anywhere in the cosmos. Here he demonstrates that gravity behaves the same way whether it pulls a cannonball back to the ground or tugs on the most distant object in the heavens. He shows that the satellites of Jupiter obey his inverse square law of gravitation, then runs through the same reasoning for the major planets and for the moon.

Next he proves that the center of the planetary system must be the sun, and explores how the mutual gravitational attraction between Saturn and Jupiter pulls both planets' orbits away from the perfect ellipse of a geometer's dream. Mathematics, Newton here affirms, is essential for the analysis of the physical world, but nature itself is more complex than any purely mathematical idealization of it.

Newton races on—so many phenomena, only so much time and energy with which to explore them. Closer to home, he analyzes the track of the moon and the implications of the observed fact that the earth is not a perfect sphere. (He proved that the gravitational pull of a spheroid would not be the same everywhere, and hence one's weight would vary slightly depending on where one stands on the earth's surface.) And, seemingly at the end of a journey from the outermost known planets to the surface of the earth, he examines the influence of moon and sun on the earth's tides. Twenty years after he looked at gravity as a purely local phenomenon, Newton here presents gravity as the engine of the system of all creation—one that binds the rise and fall of the Thames or the Gulf of Tonkin to all the observed motions of the solar system.

But Newton does not choose to end Book Three here, and his decision reveals how much the work as a whole acts to persuade and not merely to demonstrate. To be sure, no one thinks of Newton as a novelist, or of the
Principia
as a galloping read. But Book Three—and the volume in its entirety—can be experienced as a kind of epic of gravity, and to bring that tale to its heroic close, Newton spins his account outward once again, into the realm of the comets.

The passage begins slowly, with a detailed, tedious series of observations of the path of the Great Comet of 1680, the product of Newton's relentless attempts to distinguish good data from bad. From that base of unassailable evidence, Newton plots an orbit. Then he derives the same path by calculation, extracting the comet's course from just three observed positions. The two tracks—the one observed and the one predicted—match almost exactly, tracing the curve called a parabola. It does not take a huge change in trajectory to place a comet on a parabolic path instead of an elliptical one, but the distinction is crucial. Comets in elliptical orbit, like that of 1682, which we now call Halley's, return again and again. A comet on a parabolic journey passes near the earth just once. It swings by the sun and then keeps going, traveling on a path that can, in principle, carry it to the farthest extremes of the heavens.

With this, the
Principia
reaches its true climax. Nothing in Newton's science depends on the shape of this narrative. In any order, his proofs would be just as valid. But to take the reader on an odyssey that begins with the orbits of the planets and extends to bring the entire cosmos into view allows the larger implications of the Newtonian idea to emerge. At the end of the discussion of the comet of 1680, he writes, "The theory that corresponds exactly to so nonuniform a motion through the greatest part of the heavens, and that observes the same laws as the theory of the planets and that agrees exactly with exact astronomical observations
cannot fail to be true
" (italics added).

Truth, omnipresent and omnipotent: the
Principia
reveals laws of motion and gravity that do not merely describe how cannonballs fly or apples fall; they do not simply hold the earth in its orbit around the sun or regulate the dance of Saturn's moons around the ringed planet. Instead, as promised, Newton offered his world an idea that encompasses all matter, all motion, to the deepest reaches of the imaginable universe, a cosmos mapped by the paths of comets tracing out their elegant curves in journeys that end at infinity.

And then Newton rested. Edmond Halley received Book Three of the
Principia
on April 4, 1687. He spent the next three months in publisher's hell. He split the printing job between two shops, whose work had to be coordinated and supervised. Between the mathematical formulas and the woodcut illustrations, some of the sheets were so complicated that Halley found himself consumed by the demands of the book. He confided to a friend that "Mr. Newton's book ... has made me forget my duty in regard of the Societies correspondents," and that "the correction of the press costs me a great deal of time and pains." He never complained openly to Newton himself, however, writing instead of "your divine treatise" and "your excellent work."

Halley ordered a run of between two hundred fifty and four hundred copies from the printers. The finished books arrived on July 5, 1687. Halley sent twenty copies to Newton. Most of the rest went on sale. At seven shillings apiece unbound, two shillings more for a leather binding, the edition sold out almost immediately. Newton's life was about to be transformed.

F
OR JOHN LOCKE
, 1691 had been a busy year. He had left London for an open-ended stay at a friend's country house in Essex, and he had completed another book, one of his first since
A Letter Concerning Toleration,
his famous argument for freedom of conscience and belief. The new work took on a completely different though equally contentious topic: what to do about England's growing financial crisis, brought on by the plague of bad coins. After sending friends copies of the new manuscript in early December, he found himself free of immediate duties. So, at leisure at last, he resumed one of the hobbies of his youth.

Just before nine o'clock on the morning of Sunday, December 13, he left his rooms upstairs, overlooking the garden, and hurried outside to record his daily observations of the weather. His thermometer was a good one, produced by the celebrated London watchmaker Thomas Tompion. Locke recorded the temperature: 3.4 on the particular scale used on his instrument—notably colder than the "temperate" reading of 4, but not quite as cold as the day before, when Locke noted frost. This day, he found that the barometric pressure had dropped overnight and a light breeze had set in from the east. Last, he recorded the condition of the sky: thick, uniform clouds. In other words, a typical December day in the east of England: chilly, damp, and dull.

That same day, about thirty miles to the north, Isaac Newton, in a state of annoyance, began a letter. He drew out a sheet of paper, loaded his quill with ink, and began to write. He filled a page, read it, and paused. Newton was swift to take offense, and as Robert Hooke had already learned to his sorrow, Newton's enemies had to expect overwhelming retaliation for any slight, real or imagined. But today's missive was directed against that amateur meteorologist John Locke, a man whom Newton admired and by whom he was admired in turn. Newton found it difficult to strike the right note of reproach.

The crime in question? Locke had offered to help his friend Newton gain the post of Master of Charterhouse, a boys' school in London. Newton recoiled at the thought. "You seem still to think on Charterhouse," he wrote, but "I believe your notions & mine are very different about the matter." What was wrong with the proposal? Everything. "The competition is hazzardous," he complained, "and I am loathe to sing a new song" in hopes of persuading the mighty to throw him a sop. Still more galling, the pay was meager, beneath him. "Its but 200 pounds per an besides a Coach (wch I reccon not) & lodging"—not enough to live in the style to which Newton aspired nor fit reward for a man of his reputation.

And, of course, there was the problem of London.

Newton had lived in Cambridge for thirty years. All the decades of thought and labor that had transformed an awkward country boy into the dominant mind in Europe had taken place in and around the rooms overlooking the Great Court and chapel of Trinity College, from which he now wrote angrily to his friend. And yet Locke dared to suggest that he should abandon Cambridge for London, with all its filth and pretense. How could Newton express the manifold unsuitability of the suggestion? Try this: "The confinement to ye London air & a formal way of life is what I am not fond of."

Line after line expressed his sense of insult—and then he stopped. His rage cooled. He did not sign the letter.

The truth was that Newton desperately hoped to escape his intellectual cloister, and just as desperately desired the exceptionally well-connected Locke's help to do so. What had happened?

The
Principia
had, and with it Newton's sudden emergence into the circles of the great.

From the moment of its publication—and before, in fact—Edmond Halley had done his best to make sure that the
Principia
received its proper reception. He launched his campaign on the first pages of the work itself, adding to Newton's text a dedicatory ode: "Error and doubt no longer encumber us with mist; /...We are now admitted to the banquets of the Gods; / We may deal with laws of heaven above; and we now have / The secret keys to unlock the obscure earth." And, lest anyone mistake the value of the man who had found the keys to the kingdom, Halley concluded: "Join me in singing the praises of newton, who reveals all this /...No closer to the gods can any mortal rise." More soberly, in his formal review Halley argued for Newton's unique significance. "This incomparable author having at length been prevailed upon to appear in publick, has in this treatise given a most notable extent of the powers of the Mind." This Newton was the new Moses, a prophet revealing the law to the people: he had "at once shewn what are the principles of Natural Philosophy and so far derived from their consequences that he seems to have ... left little to be done by those that shall succeed him."

Newton could, of course, count on Halley's praise. The reaction that truly mattered would come from the rest of learned Europe. Over the summer and into the autumn of 1687 those responses came in.
Acta Eruditorum,
Europe's leading scientific journal, called the book "an investigation worthy of so great a mathematician." In Paris, the devout Cartesian who reviewed the
Principia
for
Le Journal des sçavans
wanted an account of gravity that would reveal the mechanism by which one object attracted another, the kind of direct connection required by orthodox mechanical philosophers. The
Principia
's purely mathematical description of gravity emphatically did not supply that kind of explanation, relying instead on the seemingly occult notion of forces acting across space—but the French reviewer still conceded that "it is not possible to make demonstrations more precise than those which [Newton] gives." The then-anonymous Scottish mathematician David Gregory wrote to Newton, offering "my most hearty thanks for having been at the pains to teach the world that which I never expected any man should have knowne." And though "your book is of so transcendent fineness and use that few will understand it," he stressed his awe on behalf of "those few who cannot but be infinitely thankful to you." Gottfried Leibniz was one of that little band who could indeed comprehend the work. His praise came in the most revealing form: in the winter of 1688–89 he rushed into print three articles that suggested he had either earlier arrived at or refuted some of Newton's conclusions. Such attempted theft acknowledged the obvious: the
Principia
had become the measure of all scientific excellence from the moment it appeared in print.

From there, it did not take long for Newton's fame to reach the next level. After discussing parts of the
Principia,
the French philosopher Marquis de l'Hospital burst out, "Good god what fund of knowledge there is in that book!" And then he pressed his companion, an acquaintance of Newton's, for "every particular of Sr I. even to the color of his hair [and]...does he eat and drink & sleep?" Then the Marquis asked the iconic question, the one that has chased Newton ever since: "Is he like other men?"

Newton had entered a realm of fame that catapulted him out of the narrow company of natural philosophers and into the wide world. One of the most worldly to fall into his orbit was an expatriate English man of letters living in the Netherlands—that genteel revolutionary John Locke. Late in 1687 Locke heard of a new book that was causing a sensation. He borrowed a copy from his friend Christiaan Huygens. But when Locke tried to read it, he found himself adrift in Newton's calculations. So he asked Huygens—after Newton the most important scientific thinker of the day—whether he could accept the
Principia
's technical arguments on faith, simply assuming their validity. Huygens confirmed that Newton had proved what he had claimed, and so Locke read on, taking each mathematical conclusion for granted.

He was enthralled. He wrote one of the early, influential reviews of the book in 1688, in the
Bibliothèque universelle,
and he made sure his English readers took the point, writing in the preface to his
Essay on Human Understanding
in 1689 that "the commonwealth of learning is not at this time without masterbuilders, whose mighty designs, in advancing the sciences, will leave lasting monuments." Chief among them "the incomparable Mr. Newton." The critical Newtonian advance, Locke wrote, was that "we might in time hope to be furnished with more true and certain Knowledge in several parts of this stupendous Machine [Nature] than hitherto we could have expected."

Locke was eager to meet any man who had devised the path to such certain truth. There was just one problem: in 1687 he was a political exile, a wanted enemy of the English state. Four years before, Locke, thanks to his long association with King Charles Il's Whig enemies, had been under routine surveillance by agents of the Crown when the Rye House Plot broke. The Rye House conspirators had planned to assassinate the King and his brother James, and the collapse of the scheme led to a wider roundup of the usual suspects. Several prominent Whigs were brought to trial and sent to the scaffold, and Locke himself faced arrest and possible execution for his guilt by association with one of the leading conspirators. Sensibly, he began to move around England and then fled the country altogether, reaching the Netherlands in September 1683. As long as the Stuarts remained in power, there he was compelled to remain.