Isaac Newton (21 page)

Its publication notwithstanding, he had never stopped working on the
Principia
. He was preparing a second edition. He scoured Greek texts for clues to his belief that the ancients had known about gravity and even the inverse-square
law. He contemplated new experiments and sought new data for his complex theory of the moon’s motions. Besides correcting printer’s errors, he was drafting and redrafting whole new sections, refining his rules for philosophy. He struggled with the inescapable hole in his understanding of gravity’s true nature. He twisted and turned: “Tis inconceivable that inanimate brute matter should (without the mediation of something else which is not material) operate upon & affect other matter without mutual contact,” he wrote one correspondent. “Gravity must be caused by an agent acting constantly according to certain laws, but whether this agent be material or immaterial is a question I have left to the consideration of my readers.”
¹⁵

He also pretended to leave to his readers—yet wrestled incessantly with—the Deity lurking in his margins. God informed Newton’s creed of absolute space and absolute time. “Can God be nowhere when the moment of time is everywhere?” he wrote in one of many new drafts that did not see light.
¹⁶
An active, interventionist God must organize the universe and the solar system: otherwise substance would be evenly diffused through infinite space or gathered together in one great mass. Surely God’s hand could be seen in the division between dark matter, like the planets, and shining matter, like the sun. All this “I do not think explicable by mere natural causes but am forced to ascribe it to the counsel & contrivance of a voluntary Agent.”
¹⁷
He returned to his alchemical experiments, too.

Whether or not Newton was like other men, by the summer of 1693 he was eating and sleeping poorly. He had lived fifty
years. He was unsettled, back and forth between the fens of Cambridgeshire and the London glare. At Cambridge his sinecure remained intact, but he scarcely taught or lectured now. In London he was angling for posts that required the king’s patronage—a position at the Royal Mint, among others—but did not fully understand his own desires. He was uneasy in his relations with his new friends, tenuous though these relations were, after a life with little practice in friendship. Fatio had tormented him by falling ill and foreshadowing his own death—“I got a grievous cold, which is fallen upon my lungs. My head is something out of order.… If I am to depart this life I could wish my eldest brother … to succeed me in Your friendship”—and then by abruptly ending their relationship and returning to Switzerland.
¹⁸
(Fatio survived sixty years more.)

Sexual feelings, too, troubled Newton’s nights. He had long since embraced celibacy. For this he had devised a rational program:

The way to chastity is not to struggle directly with incontinent thoughts but to avert the thoughts by some imployment, or by reading, or meditating on other things.…

Still, unwanted thoughts came. Ceaseless ratiocination disordered his senses.

 … the body is also put out of its due temper & for want of sleep the fansy is invigorated about what ever it sets it self upon & by degrees inclines toward a delirium in so much that those Monks who fasted most arrived to a state of seeing apparitions of weomen & their shapes.…
¹⁹

Reclusive though he remained, rumors of Newton’s mental state began to reach places where just a few years earlier his name had meant nothing: Fire had supposedly destroyed his papers. He was in a state of frenzy or melancholy or distemper. His friends had locked him away.
²⁰
He had lost all capacity for philosophical thought.

Only Pepys and Locke knew the truth. They received accusatory, delusional, and then pitiable letters. First Newton wrote Pepys:

 … for I am extremely troubled at the embroilment I am in, and have neither ate nor slept well this twelve month, nor have my former consistency of mind. I never designed to get anything by your interest, nor by King James favour, but am now sensible that I must withdraw from your acquaintance, and see neither you nor the rest of my friends any more.…

Then Locke:

Sir—

Being of opinion that you endeavoured to embroil me with woemen & by other means I was so much affected with it as that when one told me you were sickly and would not live I answered twere better you were dead.… I beg your pardon also for saying or thinking that there was a designe to sell me an office, or to embroile me. I am

your most humble & most

unfortunate Servant

Is. Newton
²¹

Sex and ambition—all embroiled. Madness and genius as well; in the reputation spreading now, these imponderable qualities reinforced each other. Pepys bruited suggestive hints. “I was loth at first dash to tell you,” he wrote one friend. He was concerned, “lest it should arise from that which of all mankind I should least dread from him and most lament for,—I mean a discomposure in head, or mind, or both.”
²²

Yet by fall Newton delved again into mathematical studies. He was systematizing ancient geometrical analysis: especially the quadrature and construction of unruly curves. He continued to think of this work as rediscovery and restoration. After all, no one had fully plumbed the ancients’ secrets. Lost manuscripts still turned up in dusty collections. There was such grandeur and purity in these old truths, which could burst into life, preserved across the millennium in Arabic as if in amber. “The Analysis of the Ancients,” he wrote, “is more simple more ingenious & more fit for a Geometer than the Algebra of the Moderns.”
²³
Once again Newton’s own studies, even when they were most innovative, were for himself alone. With few exceptions his treatises remained in the purgatory of his private papers.

At the University of Oxford enthusiastic students (but there were few) could already hear astronomical lectures on the system of Newton.
²⁴
Not at Cambridge, however. “We at Cambridge, poor Wretches, were ignominiously studying the fictitious Hypotheses of the Cartesian,” one fellow recalled later.
²⁵

On the continent of Europe the Newtonian ideas were inspiring philosophers to frantic reformulations of their own theories. “Vortices destroyed by Newton,” Huygens jotted. “Vortices of spherical motion in their place.”
²⁶
He debated mechanisms of gravity with the German mathematician and diplomat Gottfried Leibniz, who was rushing to publish his own version of planetary dynamics. “I noticed you are in favor of a vacuum and of atoms,” Leibniz wrote. “I do not see the necessity which compels you to return to such extraordinary entities.”
²⁷
Newton’s unmechanical gravity appalled him. “The fundamental principle of reasoning is,
nothing is without cause
,” he wrote. “Some conceive gravity to signify the attraction of bodies toward the bulk of the Earth, or their enticement towards it by a certain sympathy.… He is admitting that no cause underlies the truth that a stone falls towards the Earth.”
²⁸
It look Leibniz another year to brave an approach to Newton himself. He penned a salutation in grand style across a sheet of paper:
“illustri viro ISAACO NEUTONO.”
²⁹

“How great I think the debt owed you,…” Leibniz began. He mentioned that he, too, had been trying to extend geometry with a new kind of mathematical analysis, “the application of convenient symbols which exhibit differences and sums.… And the attempt did not go badly. But to put the last touches I am still looking for something big from you.” He confessed that he had been looking everywhere for publications by Newton. He had come across the name in a catalogue of English books, but that was a different Newton.

Besides mathematics Newton had returned to the most tortuous unfinished problem in the
Principia
:
a
full theory
of the moon’s motion. This was no mere academic exercise; given a precise recipe for predicting the moon’s place in the sky, sailors with handheld astrolabes should finally be able to calculate their longitude at sea. A lunar theory should follow from Newton’s theory of gravity: the ellipse of the lunar orbit crosses the earth’s own orbital plane at a slant angle; the sun’s attraction twists the lunar orbit, apogee and perigee revolving over a period of roughly nine years. But the force of solar gravity itself varies as the earth and moon, in their irregular dance, approach and recede from the sun. With a revised edition of the
Principia
in mind, he needed more data, and this meant calling upon the Astronomer Royal. Late in the summer of 1694 he boarded a small boat to journey down the River Thames and visit, for the first time, Flamsteed in Greenwich. He pried loose fifty lunar observations and a promise of one hundred more. Flamsteed was reluctant, and he demanded secrecy, because he considered these records his personal property. Soon Newton wanted more—syzygies and quadratures and octants, to be delivered by Flamsteed via penny post to a carrier who traveled between London and Cambridge every week. Flamsteed insisted on signed receipts. Newton cajoled Flamsteed and then pressured him. Revealing the data would make Flamsteed famous, Newton promised—“make you readily acknowledged the most exact observer that has hitherto appeared in the world.” But the data alone would be worthless without a theory to give them meaning—“if you publish them without such a theory … they will only be thrown into the heap of the observations of former astronomers.”
³⁰
Indeed these men needed each other—Newton desperate for data that no one else in England could
provide; Flamsteed desperate for any sign of gratitude or respect (“Mr Ns approbation is more to me then the cry of all the Ignorant in the world,” he wrote that winter)—and before long, they hated each other.

Two struggles continued in parallel: Newton grappled with Flamsteed and with a fiendish dynamical perturbation problem. When the astronomer complained of headaches, Newton advised him to bind his head with a garter.
³¹
Finally he learned that Flamsteed had let people know about the work in progress and rebuked him bitterly:

I was concerned to be publickly brought upon the stage about what perhaps will never be fitted for the publick & thereby the world put into an expectation of what perhaps they are never like to have. I do not love to be printed upon every occasion much less to be dunned & teezed by forreigners about Mathematical things or thought by our own people to be trifling away my time.…
³²

Flamsteed spilled his agony into the margins: “Was Mr Newton a trifler when he read Mathematicks for a sallery at Cambridge,” he railed, and then added, “Persons thinke too well of themselves to acknowledge they are beholden to those who have furnisht them with the feathers they pride themselves in.”
³³
Flamsteed took some small pleasure in reporting rumors of Newton’s death: “It served me to assure your freinds that you were in health they haveing heard that you were dead againe.” In return, for the rest of Flamsteed’s life, he was a victim of Newton’s implacable ruthlessness.

But Newton’s fear of raising expectations was genuine.
He grappled with distortions in the data caused by atmospheric refraction. The gravitational interaction of three disparate bodies did not lend itself to ready solution.

He did ultimately produce a practical formula for calculating the moon’s motion: a hybrid sequence of equations and measurements that appeared first in 1702, as five Latin pages inside David Gregory’s grand
Astronomiæ Elementa
. Gregory called it Newton’s
theory
, but in the end Newton had omitted any mention of gravitation and buried his general picture under a mass of details. (He began: “The Royal Observatory at Greenwich is to the West of the Meridian of Paris 2° 19’. Of Uraniburgh 12° 51’ 30”. And of Gedanum 18° 48’.”) Halley quickly reprinted Newton’s text as a booklet in English, saying, “I thought it would be a good service to our Nation.… For as Dr. Gregory’s Astronomy is a large and scarce Book, it is neither everyone’s Money that can purchase it.” Halley hailed the theory’s exactness and hoped to encourage people to use it, but “the Famous Mr. Isaac Newton’s Theory of the Moon” was little noted and quickly forgotten.
³⁴

Newton abandoned his Cambridge cloister for good in 1696. His smoldering ambition for royal preferment was fulfilled. Trinity had been his home for thirty-five years, but he departed quickly and left no friends behind.
³⁵
As he emphatically told Flamsteed, he was now occupied by the King’s business. He had taken charge of the nation’s coin.

14
 
No Man Is a Witness in His Own Cause