Kepler Read online

  It was a pretty enough town. He was impressed when first he glimpsed it, the river, the spires, the castle-crowned hill, all blurred and bright under a shower of April rain. There seemed a largeness here, a generosity, which he fancied he could see even in the breadth and balance of the buildings, so different from the beetling architecture of his native Württemberg towns. The people too appeared different. They were prome-naders much given to public discourse and dispute, and Johannes was reminded that he had come a long way from home, that he was almost in Italy. But it was all an illusion. Presently, when he had examined more closely the teeming streets, he realised that the filth and the stench, the cripples and beggars and berserks, were the same here as anywhere else. True, they were Protestant loonies, it was Protestant filth, and a Protestant heaven those spires sought, hence the wider air hereabout: but the Archduke was a rabid Catholic, and the place was crawling with Jesuits, and even then at the Stiftsschule there was talk of disestablishment and closure.

  He, who had been such a brilliant student, detested teaching. In his classes he experienced a weird frustration. The lessons he had to expound were always, always just somewhere off to the side of what really interested him, so that he was forever holding himself in check, as a boatman presses a skiff against the run of the river. The effort exhausted him, left him sweating and dazed. Frequently the rudder gave way, and he was swept off helplessly on the flood of his enthusiasm, while his poor dull students stood abandoned on the receding bank, waving weakly.

  The Stiftsschule was run in the manner of a military academy. Any master who did not beat blood out of his boys was considered lax. (Johannes did his best, but on the one occasion when he could not avoid administering a flogging his victim was a great grinning fellow almost as old as he, and a head taller.) The standard of learning was high, sustained by the committee of supervisors and its phalanx of inspectors. Johannes greatly feared the inspectors. They dropped in on classes unannounced, often in pairs, and listened in silence from the back, while his handful of pupils sat with arms folded, hugging themselves, and gazed at him, gleefully attentive, waiting for him to make a fool of himself. Mostly he obliged, twitching and stammering as he wrestled with the tangled threads of his discourse.

  "You must try to be calm," Rector Papius told him. "You tend to rush at things, I think, forgetting perhaps that your students do not have your quickness of mind. They cannot follow you, they become confused, and then they complain to me, or…" he smiled "… or their fathers do. "

  "I know, I know, "Johannes said, looking at his hands. They sat in the rector's room overlooking the central courtyard of the school. It was raining. There was wind in the chimney, and balls of smoke rolled out of the fireplace and hung in the air around them, making his eyes sting. "I talk too quickly, and say things before I have had time to consider my words. Sometimes in the middle of a class I change my mind and begin to speak of some other subject, or realise that what I have been saying is imprecise and begin all over again to explain the matter in more detail. " He shut his mouth, squirming; he was making it worse. Dr Papius frowned at the fire. "You see, Herr Rector, it is my cupiditas speculandi that leads me astray."

  "Yes, " the older man said mildly, scratching his chin, "there is in you perhaps too much… passion. But I would not wish to see a young man suppress his natural enthusiasm. Perhaps, Master Kepler, you were not meant for teaching?"

  Johannes looked up in alarm, but the rector was regarding him only with concern, and a touch of amusement. He was a gentle, somewhat scattered person, a scholar and physician; no doubt he knew what it was to stand all day in class wishing to be elsewhere. He had always shown kindness to this strange little man from Tübingen, who at first had so appalled the more stately members of the staff with his frightful manners and disconcerting blend of friendliness, excitability and arrogance. Papius had more than once defended him to the supervisors.

  "I am not a good teacher, ' 'Johannes mumbled, "I know. My gifts lie in other directions. "

  "Ah yes, " said the rector, coughing; "your astronomy. " He peered at the inspectors' report on the desk before him. "You teach that well, it seems?"

  "But I have no students!"

  "Not your fault-Pastor Zimmermann himself says here that astronomy is not everyone's meat. He recommends that you be put to teaching arithmetic and Latin rhetoric in the upper school, until we can find more pupils eager to become astronomers."

  Johannes understood that he was being laughed at, albeit gently.

  "They are ignorant barbarians! " he cried suddenly, and a log fell out of the fire. "All they care for is hunting and warring and looking for fat dowries for their heirs. They hate and despise philosophy and philosophers. They they they-they do not deserve…" He broke off, pale with rage and alarm. These mad outbursts must stop.

  Rector Papius smiled the ghost of a smile. "The inspectors?"

  "The…?"

  "I understood you to be describing our good Pastor Zimmermann and his fellow inspectors. It was of them we were speaking."

  Johannes put a hand to his brow. "I-I meant of course those who will not send their sons for proper instruction. "

  "Ah. But I think, you know, there are many among our noble families, and among the merchants also, who would consider astronomy not a proper subject for their sons to study. They burn at the stake poor wretches who have had less dealings with the moon than you do in your classes. I am not defending this benighted attitude to your science, you understand, but only drawing it to your attention, as it is my-"

  "But-"

  "-As it is my duty to do. "

  They sat and eyed each other, Johannes sullen, the rector apologetically firm. Grey rain wept on the window, the smoke billowed. Johannes sighed. "You see, Herr Rector, I cannot-"

  "But try, will you, Master Kepler: try?"

  He tried, he tried, but how could he be calm? His brain teemed. A chaos of ideas and images churned within him. In class he fell silent more and more frequently, standing stock still, deaf to the sniggering of his students, like a crazed hiero-phant. He traipsed the streets in a daze, and more than once was nearly run down by horses. He wondered if he were ill. Yet it was more as if he were… in love! In love, that is, not with any individual object, but generally. The notion, when he hit on it, made him laugh.

  At the beginning of 1595 he received a sign, if not from God himself then from a lesser deity surely, one of those whose task is to encourage the elect of this world. His post at the Stiftsschule carried with it the title of calendar maker for the province of Styria. The previous autumn, for a fee of twenty florins from the public coffers, he had drawn up an astrological calendar for the coming year, predicting great cold and an invasion by the Turks. In January there was such a frost that shepherds in the Alpine farms froze to death on the hillsides, while on the first day of the new year the Turk launched a campaign which, it was said, left the whole country from Neustadt to Vienna devastated. Johannes was charmed with this prompt vindication of his powers (and secretly astonished).  a sign, yes, surely. He set to work in earnest on the cosmic mystery.

  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 increasin
g 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 summo
ned 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.