Kepler (4 page)

He had not the solution, yet; he was still posing the questions. The first of these was: Why are therejust six planets in the solar system? Why not five, or seven, or a thousand for that matter? No one, so far as he knew, had ever thought to ask it before. It became for him the fundamental mystery. Even the formulation of such a question struck him as a singular achievement.

He was a Copernican. At Tübingen his teacher Michael Mästlin had introduced him to that Polish master's world system. There was for Kepler something almost holy, something redemptive almost, in that vision of an ordered clockwork of sun-centred spheres. And yet he saw, from the beginning, that there was a defect, a basic flaw in it which had forced Copernicus into all manner of small tricks and evasions. For while the
idea
of the system, as outlined in the first part of
De revolutionibus,
was self-evidently an eternal truth, there was in the working out of the theory an ever increasing accumulation of paraphernalia-the epicycles, the equant point, all that-necessitated surely by some awful original accident. It was as if the master had let fall from trembling hands his marvellous model of the world's working, and on the ground it had picked up in its spokes and the fine-spun wire of its frame bits of dirt and dead leaves and the dried husks of worn-out concepts.

Copernicus was dead fifty years, but now for Johannes he rose again, a mournful angel that must be wrestled with before he could press on to found his own system. He might sneer at the epicycles and the equant point, but they were not to be discarded easily. The Canon from Ermland had been, he suspected, a greater mathematician than ever Styria's calendar maker would be. Johannes raged against his own inadequacies. He might know there was a defect, and a grave one, in the Copernican system, but it was a different matter to find it. Nights he would start awake thinking he had heard the old man his adversary laughing at him, goading him.

And then he made a discovery. He realised that it was not so much in what he
had
done that Copernicus had erred: his sin had been one of omission. The great man, Johannes now understood, had been concerned only to see the nature of things demonstrated, not explained. Dissatisfied with the Ptolemaic conception of the world, Copernicus had devised a better, a more elegant system, which yet, for all its seeming radicalism, was intended only, in the schoolman's phrase, to save the phenomena, to set up a model which need not be empirically true, but only plausible according to the observations.

Then had Copernicus believed that his system was a picture of reality, or had he been satisfied that it agreed, more or less, with appearances? Or did the question arise? There was no sustained music in that old man's world, only chance airs and fragments, broken harmonies, scribbled cadences. It would be Kepler's task to draw it together, to make it sing. For truth was the missing music. He lifted his eyes to the bleak light of winter in the window and hugged himself. Was it not wonderful, the logic of things? Troubled by an inelegance in the Ptolemaic system, Copernicus had erected his great monument to the sun, in which there was embedded the flaw, the pearl, for Johannes Kepler to find.

But the world had not been created in order that it should sing. God was not frivolous. From the start he held to this, that the song was incidental, arising naturally from the harmonious relation of things. Truth itself was, in a way, incidental. Harmony was all. (Something wrong, something wrong! but he ignored it.) And harmony, as Pythagoras had shown, was the product of mathematics. Therefore the harmony of the spheres must conform to a mathematical pattern. That such a pattern existed Johannes had no doubt. It was his principal axiom that nothing in the world was created by God without a plan the basis of which is to be found in geometrical quantities. And man is godlike precisely, and only, because he can think in terms that mirror the divine pattern. He had written: The mind grasps a matter so much the more correctly the closer it approaches pure quantities as its source. Therefore his method for the task of identifying the cosmic design must be, like the design itself, founded in geometry.

Spring came to Graz and, as always, took him by surprise. He looked out one day and there it was in the flushed air, a quickening, a sense of vast sudden swooping, as if the earth had hurtled into a narrowing bend of space. The city sparkled, giving off light from throbbing window panes and polished stone, from blue and gold pools of rain in the muddied streets. Johannes kept much indoors. It disturbed him, how closely the season matched his present mood of restlessness and obscure longing. The Shrovetide carnival milled under his window unheeded, except when a comic bugle blast or the drunken singing of revellers shattered his concentration, and he bared his teeth in a soundless snarl.

Perhaps he was wrong, perhaps the world was not an ordered construct governed by immutable laws? Perhaps God, after all, like the creatures of his making, prefers the temporal to the eternal, the makeshift to the perfected, the toy bugles and bravos of misrule to the music of the spheres. But no, no, despite these doubts, no: his God was above all a god of order. The world works by geometry, for geometry is the earthly paradigm of divine thought.

Late into the nights he laboured, and stumbled through his days in a trance. Summer came. He had been working without cease for six months, and all he had achieved, if achievement it could be called, was the conviction that it was not with the planets themselves, their positions and velocities, that he must chiefly deal, but with the intervals between their orbits. The values for these distances were those set out by Copernicus, which were not much more reliable than Ptolemy's, but he had to assume, for his sanity's sake, that they were sound enough for his purpose. Time and time over he combined and recom-bined them, searching for the relation which they hid. Why are there just six planets? That was a question, yes. But a profoun-der asking was, why are there just these distances between them? He waited, listening for the whirr of wings. On that ordinary morning in July came the answering angel. He was in class. The day was warm and bright. A fly buzzed in the tall window, a rhomb of sunlight lay at his feet. His students, stunned with boredom, gazed over his head out of glazed eyes. He was demonstrating a theorem out of Euclid -afterwards, try as he might, he could not remember which -and had prepared on the blackboard an equilateral triangle. He took up the big wooden compass, and immediately, as it always contrived to do, the monstrous thing bit him. With his wounded thumb in his mouth he turned to the easel and began to trace two circles, one within the triangle touching it on its three sides, the second circumscribed and intersecting the vertices. He stepped back, into that box of dusty sunlight, and blinked, and suddenly something, his heart perhaps, dropped and bounced, like an athlete performing a miraculous feat upon a trampoline, and he thought, with rapturous inconsequence: I shall live forever. The ratio of the outer to the inner circle was identical with that of the orbits of Saturn and Jupiter, the furthermost planets, and here, within these circles, determining that ratio, was inscribed an equilateral triangle, the fundamental figure in geometry. Put therefore between the orbits of Jupiter and Mars a square, between Mars and earth a pentagon, between earth and Venus a… Yes. Yes. The diagram, the easel, the very walls of the room dissolved to a shimmering liquid, and young Master Kepler's lucky pupils were treated to the rare and gratifying spectacle of a teacher swabbing tears from his eyes and trumpeting juicily into a dirty handkerchief.

At dusk he rode out of the forest of Schönbuch. The bright March day had turned to storm, and a tawny light was sinking in the valley. The Neckar glimmered, slate-blue and cold. He stopped on the brow of a hill and stood in the stirrups to breathe deep the brave tempestuous air. He remembered Swabia not like this, strange and fierce: was it he, perhaps, that had changed? He had new gloves, twenty florins in his purse, leave of absence from the Stiftsschule, this dappled grey mare lent him by his friend the district secretary of Styria, Stefan Speidel, and, safe in a satchel by his side, wrapped in oilskin, most precious of all, his manuscript. The book was done, he had come to Tübingen to publish it. Black rain was falling when he entered the narrow streets of the town, and lanterns flickered on the bastioned walls of Hohentubingen above him. After the annunciation of July, it had taken seven more months of labour, and the incorporation of a third dimension into his calculations, to round out his theory and complete the
Mysterium.
Night, storm, a solitary traveller, the muted magnificence of the world; a trickle of rain got under his collar, and his shoulder-blades quivered like nascent wings.

Presently he was sitting in a bed, in a low brown room at The Boar, with a filthy blanket pulled to his chin, eating oatcakes and drinking mulled wine. Rain drummed on the roof. From the tavern below there rose a raucous singing-fine hearty people, the Swabians, and prodigious topers. Many a skinful of Rhenish he himself as a student had puked up on that rush-strewn floor down there. It surprised him, how happy he was to be back in his homeland. He was downing the dregs of the jug in a final toast to Mistress Fame, that large and jaunty goddess, when the potboy banged on the door and summoned him forth. Bleared and grinning, half drunk, and still with the blanket clutched about him, he struggled down the rickety stairs. The aleroom had the look of a ship's cabin, the drinkers swaying, candlelight swinging, and, beyond the streaming windows, the heaving of the oceanic night. Michael Mästlin, his friend and sometime teacher, rose from a table to meet him. They shook hands, and found themselves grappling with an unexpected shyness. Johannes without preamble said: "I have written my book." He frowned at the filthy table and the leathern cups: why did things not quake at his news?

Professor Mästlin was eyeing the blanket. "Are you ill?"

"What? No; cold, wet. I have lately arrived. You had my message? But of course, since you are here. Ha. Though my piles, forgive my mentioning it, are terrible, after that journey."

"You don't mean to lodge here, surely?-no no, you shall stay with me. Come, lean on my arm, we must see to your bags."

"I am not-"

"Come now, I say. You are on fire, man, and your hands, look, they're shaking. "

"I am not, I tell you, I am
not ill."

The fever lasted for three days. He thought he might die. Supine on a couch in Mästlin's rooms he raved and prayed, plagued by visions of gaudy devastation and travail. His flesh oozed a noxious sweat: where did it come from, so much poison? Mästlin nursed him with a bachelor's unhandy tenderness, and on the fourth morning he woke, a delicate vessel lined with glass, and saw through an angle of window above him small clouds sailing in a patch of blue sky, and he was well.

Like a refining fire the fever had rinsed him clean. He went back to his book with new eyes. How could he have imagined it was finished? Squatting in a tangle of sheets he attacked the manuscript, scoring, cutting, splicing, taking the theory apart and reassembling it plane by plane until it seemed to him miraculous in its newfound elegance and strength. The window above him boomed, buffeted by gales, and when he raised himself on an elbow he could see the trees shuddering in the college yard. He imagined washes of that eminent exhilarated air sweeping through him also. Mästlin brought him his food, boiled fish, soups, stewed lights, but otherwise left him alone now; he was nervous of this excitable phenomenon, twenty years his junior, perched on the couch in a soiled nightshirt, like an animated doll, day after day, scribbling. He warned him that the sickness might not be gone, that the feeling of clarity he boasted of might be another phase of it. Johannes agreed, for what was this rage to work, this rapture of second thoughts, if not an ailment of a kind?

But he recovered from that too, and at the end of a week the old doubts and fears were back. He looked at his remade manuscript. Was it so much better than before? Had he not merely replaced the old flaws with new ones? He turned to Mästlin for reassurance. The Professor, shying under this intensity of need, frowned into a middle distance, as if surreptitiously spying out a hole down which to bolt. "Yes," he said, coughing, "yes, the idea is, ah, ingenious, certainly."

"But do you think it is
true?"

Mästlin's frown deepened. It was a Sunday morning. They walked on the common behind the main hall of the university. The elms thrashed under a violent sky. The Professor had a grizzled beard and a drinker's nose. He weighed matters carefully before committing them to words. Europe considered him a great astronomer. "I am, "he announced, "of the opinion that the mathematician has achieved his goal when he advances hypotheses to which the phenomena correspond as closely as possible. You yourself would also withdraw, I believe, if someone could offer still better principles than yours. It by no means follows that the reality immediately conforms to the detailed hypotheses of every master."

Johannes, debilitated and ill-tempered, scowled. This was the first time he had ventured out since the fever had abated. He felt transparent. There was a whirring high in the air, and then suddenly a crash of bells that made his nerves vibrate. "Why waste words?" he said, yelled, bells,
damn.
"Geometry existed before the Creation, is co-eternal with the mind of God,
is
God himself..
."

Bang.

"O!" Mästlin stared at him.

"… For what," smoothly, "exists in God that is not God himself?" A grey wind swarmed through the grass to meet him; he shivered. "But we are mouthing quotations merely: tell me what you truly think. "

"I have said what I think," Mästlin snapped.

"But that, forgive me, magister, is scholastic shilly-shally."

"Well then, I am a schoolman!"

"You, who teaches his students-who taught
me
-the heliocentric doctrine of Copernicus,
you
a schoolman?" but turned on the professor all the same a thoughtful sidelong glance.