Kepler's Witch Read online

  On May 17, 1583, Johannes traveled to Stuttgart to take the Landesexamen. He was eleven years old at the time, and his score on the examination was so high it gave him a place in the duke’s scholarship system even though he came from an undistinguished family. As soon as his parents gave permission, the Duke of Württemberg assumed complete financial responsibility for young Johannes. The duchy would until the end of his school days supply his tuition, food, and clothing, and although he could never leave the system without repaying the duchy for his study, he could be expelled for misconduct or theologically suspicious beliefs.

  Thirteen months later, after the failure of his inn, Heinrich dragged the family back to Leonberg, where Johannes could complete his Latin school education, and where Katharina gave birth to Kepler’s sister, Margaretha, on June 26. Margaretha would become the only one of his siblings that Johannes truly cared for.

  It was in Leonberg that Kepler’s intellectual personality took shape. If any such emergence could be pinpointed to one day, it would have to be that Sunday when Kepler, aged twelve, heard a fresh young deacon in his church preach a long, violent sermon against the Calvinists. The growing dissension between the Christian denominations had been preying on Kepler’s mind for some time, though it hadn’t come to full consciousness until that day. It troubled him terribly that Christians could be so vicious to one another. From that point on, he questioned what the preachers said and resolved to test them. Whenever one glossed a biblical text in a way that he found troubling, he pulled himself off to a corner with the Luther Bible and, in good Lutheran fashion, consulted the text himself. With time, he realized that the very people that the preachers were attacking so vehemently had their good points too.

  To understand Kepler the man, the philosopher, the scientist, however, one must first understand Kepler the Lutheran. The new faith was in his marrow, and all his science was at heart a prayer. In his childhood and through his school days, Lutheranism surrounded him, even in Catholic Weil der Stadt, largely because of old Sebald and his grandmother Katharina. Although his parents might possibly have baptized him in the old faith in the baptistery of the Catholic parish of Sts. Peter and Paul, he spent his life utterly fixed in the new one. It is important to remember, however, that by the time that Kepler was in school, Württemberg Lutheranism had become profoundly conservative, as conservative in its own way as Roman Catholicism, and in spite of its position as the new way of Christianity, it was closer to what we would call fundamentalism than it was to liberalism. This would cause Kepler no end of trouble in the years to come. But in spite of everything, Lutheran he was, and Lutheran he would remain, even when his livelihood and his career would have been greatly enhanced by conversion to Catholicism.

  Once in Leonberg, he bathed in Lutheranism—in church, in his home, even on the street. Street vendors, innkeepers, soldiers, old widows, and laughing children all daily peppered their speech with blessings and curses, calling on God to support, to witness, to punish. It is impossible for us to understand a world so permeated with religion, for the daily life of ordinary people was forever filled with God—and the devil. Good and evil in a harvest dance, with human souls caught between.

  Grounding this was the Bible, newly available to all. For Luther, God’s divine law was revealed only in Scripture and not through observation of either nature or society. Although creation was for Luther the most beautiful work of all, where the Creator had left vestiges of the divine like broken twigs along a forest path, the study of nature could never reveal the wholeness of truth. Only the Word of God could do this, for human reason alone did not have the power. Astronomy must therefore be separate from theology, for human reason could never come to understand God’s will for the world. Sola scriptura—the Scriptures alone reveal the mind of God and should alone guide the affairs of human beings.

  On the other hand, Philipp Melanchthon, one of Luther’s counterparts in the Reformation in Wittenberg, saw a strong connection between natural law and moral law and maintained that an understanding of nature could indeed inform our understanding of God and creation. As the reformer of education in the new faith, Melanchthon saw philosophy as essential to a trained Christian mind and mathematics as essential to philosophy. Like Plato, he set forth mathematics as the preeminent subject in the philosophy curriculum, for not only did mathematics have practical importance in people’s lives, but it also refined the mind in logic. Arithmetic and geometry, Melanchthon said, reveal the order of things and teach the mind to recognize and separate things, for the “soul is a reasoning being which understands things and observes order.”

  For Melanchthon, as for Kepler, the order of the world was a shadow of the mind of God. The human mind vibrated with this order, felt it, and reacted to it. In Scholastic language, the mind was co-natural with the order of the world—they were made for each other and could be tuned to each other like radios. Philosophy was essential, because it trained the mind to this divine order, and astronomy was central to philosophy, because the most perfect order, the only true harmony, hummed in the celestial spheres. These heavens, this order, had been established by God to bring human beings to perfection. Just as the heavens move in perfect circles, gliding through the night sky, stately, unhurried, noble, like kings in procession, so the trained mind moves in rational patterns, argument to argument, from truth to greater truth, even to the greatest truth of all, the truth of God. Of all the mathematical sciences, astronomy was the most important. The whole of mathematics, arithmetic as well as geometry, was important for Melanchthon only because it revealed the order of the heavens.

  Thus, the heavens contain a celestial light that the ordered mind contemplates and, in doing so, plumbs the secret places of God, revealing even the Creator to the observing mind, for only by design, a divine design, could such heavenly order come about. And this design is not only wonderful in itself, but also useful to human beings, for the order of the heavens is also a moral lesson. Its perfection, regularity, and harmony teach the divine law of righteousness to the human soul, fallen and beset by chaos. Nothing in the heavens occurred by chance for Melanchthon. It is God’s will that human beings know the divine, and the study of the perfection of the sky is one of the ways into that knowledge, a knowledge and a truth that will set you free. Those who believe that the heavens exist only by chance wage war against the human soul.

  For Melanchthon, unlike Luther, the order of the heavens revealed God’s mind, both as Creator and as Father of the human race. The movements of the sun and moon, stars and planets are used to regulate human action, setting forth times for planting and for harvesting, times to buy and sell, and times for rest. By ordering human lives, God reveals the truth—that order is of God and that chaos is of the Evil One. Those who stand on the side of the angels support God’s order on earth as it is revealed in the heavens. The stately movement of the celestial spheres, therefore, becomes the template for human morality.

  The stars also carry prophecy, portents and signs of events to come, most commonly disasters. God reveals the future in the stars, for the stars reveal the mind of God. Events in this world come from the movements of the heavens as effect follows cause. Thus, Melanchthon, like most thinkers of his day, trusted in the astrological sciences, for the stars in their perfection were closer to God, to the First Mover of Aristotle, who moves all things without Himself being moved. Therefore, a person can read the stars and predict the future, at least in a general way. Nevertheless, not all readings of the heavens are equally valid. Any attempt to observe the sky in order to predict specific events or to read the particulars of the future was superstition for Melanchthon. True astrology is the science of the subtle influences that the stars have over the inclinations of human souls and human societies.5 This was not too far from Kepler’s own view, in which the stars helped to shape the general flow of the world, its tendencies and its limitations, but did not control individual events. (Contemporary science no longer believes this of the stars, but still there
are influences. Our own genes have taken the place of Melanchthon’s and Kepler’s stars, and the inclinations of our hearts are influenced by strings of proteins.)

  It is this embrace of astrology more than anything else that puts Kepler at a distance from our age. Astrology lost its credibility in the century after Kepler, when Newton, who still believed ferociously in alchemy, abandoned it for a more thoroughgoing mechanical cosmology. What Newton did not acknowledge, however, for which he was chided by other astronomers in his time, was that this mechanical insight had first been Kepler’s. In Kepler’s own day, however, astrology was still queen and the larger towns all across Europe, from Stuttgart to Leonberg, from Tübingen to Prague all built astronomical clocks, not to tick off the seconds of a person’s life—Click! Then gone forever—but to map out the heavenly realms, to give insight into the events of the day. Kepler’s attachment to astrology followed Melanchthon’s and was Lutheran to the bone. Kepler’s warnings about using astrological predictions as a reliable guide mirrored Melanchthon’s concerns.

  Oddly enough, this ease with astrology puts the sensibilities of the seventeenth century at some distance even from those of modern Christians. Although liberal Christians follow Newton and wave off astrology as empty pseudo-science, conservative and fundamentalist Christians fear it as a manifestation of the occult, as dark superstition. How different this is from the ideas held by the founders of Protestantism and seventeenth-century Christians in general, who saw the stars and their movements as divinely created sacraments, windows into the mind of God. Still, the stars were incomplete windows. Astronomy can reveal the order of God built into the world and open the eyes of human beings to God’s good government, but it cannot achieve the revelation of Christ and the story of the salvation of humanity. Astronomy can make visible something of the intentions God had for the world, but not the story of God’s relationship with the human race. The mind that shaped the world has left its imprint in the world and has given us access to it. Partly, according to Melanchthon, this is because the human mind originated in the heavens and is a direct creation of God. But the human mind has fallen, been corrupted by sin, and the story of God’s generosity cannot, therefore, be written in the stars.

  On October 16, 1584, after Kepler graduated from the Latin school, his parents sent him off to the lower seminary, the school at Adelberg, once a monastery of the Premonstratensian Order near Mt. Hohenstaufen. Two years later he went on to the upper seminary in the Cistercian abbey at Maulbronn. The children of the wealthy who attended the Latin school afterward studied at the Pädagodium, a college in Stuttgart or in Tübingen, which was meant to prepare them for entry into the university. The monastery schools, on the other hand, were an alternative route into the university reserved mainly for the gifted children of the lower classes, which finally led to an education at the Stift, the Lutheran seminary.6 All told, there were thirteen monastery schools in the duchy of Württemberg, forming a system that was unique throughout the empire, and with the Stift they formed a separate school system from the Pädagodium and the normal university.

  It was in Adelberg that Kepler formed his ideas on the ubiquity doctrine that got him into so much trouble in his later life. The ubiquity doctrine was Luther’s response to Thomas Aquinas’s doctrine of transubstantiation, whereby the hidden substance, the underlying reality, of the bread and wine were transformed during the Mass into the Body and Blood of Christ. Luther disagreed with this, as did all the Reformers, and presented the alternative idea that the communicant does indeed receive the Body and Blood, because, by his existence as God, Christ’s Body and Blood became universal and were everywhere. A person could receive the true presence of Christ because Christ was everywhere. The Calvinists denied this idea, claiming that the bread and wine remain bread and wine and that the communicant receives special assistance from Christ, who is in heaven, during Communion. It was this idea that Kepler leaned toward, since he could not find any mention of the ubiquity doctrine in either Scripture or the church fathers. (The Lutheran church eventually abandoned the ubiquity doctrine altogether.)

  Time and again, the preachers railed against the Calvinists. They took special note of the Calvinist doctrine of Communion and shot as many holes in it as they could. But Kepler, true to form, studied the scriptural texts mentioned, meditated on them, and finally concluded that the Calvinists were right all along. But that was as far as he would go with them. He could never accept the doctrine of predestination, for he thought it barbaric that God would condemn people for no fault of their own, just because they weren’t “chosen.” One of his fellow seminarians at the time teased him about his constant doubts, saying “Freshman, do you want to contest the predestination as well?” As it turned out, he did. After a great internal debate, he decided that he could not accept that pagans would be damned by a loving God, just because they had never learned of Christ.7

  On March 5, 1587, his brother Christoph was born. Two years later, in 1589, after Heinrich the father tried to sell sixteen-year-old Heinrich the son into slavery, Heinrich the son ran away from home. Soon after, Heinrich the father also disappeared, for the last time, running off to fight for the king of Naples and then to die somewhere far away. All indications are that he was not much missed.

  Meanwhile, young Johannes, off in the seminary, thrived. Up at four in the morning on summer days and five in the winter, Johannes lived the life of a monk, singing psalms as the sun rose, scrubbing hallways and classrooms, then studying the rest of the day. The boys ate and worked and studied and prayed from waking to sleeping, with no time for play. They ate in silence, and all of them dressed in the same knee-length coat without sleeves. They read, studied, and even disputed in Latin, so that they became more adept in that language than in their own workaday German. Along the way, they read Xenophon, Demosthenes, Virgil, and Cicero, but no Catullus or Ovid. They studied rhetoric, dialectics, and music. Later on, once they reached the upper seminary, they would study geometry and arithmetic.8

  He loved the study and pursued it with the same intensity he pursued everything. But then he started having trouble. His doubts about the ubiquity doctrine and his typically aggressive defense of his own views set both his teachers’ and his schoolmates’ teeth on edge. Preachers from Tübingen visited Adelberg while Kepler was there, and they preached Lutheran doctrine with great fire and vehemence. But Kepler, true to form, his mind always toeing out new paths, didn’t quite agree with any of them, because he was always looking for the other side, the place where those vilified enemies of the true faith were right. In particular, he didn’t like the manner of the sermons, the viciousness of them. And typically he argued his positions forcefully and with wry humor, which led to arguments and sometimes to fistfights. “Be careful,” a friend of his told him. “Take such stands in the classroom only. If you speak like that in public, you could be called a heretic.”

  “My beliefs are my beliefs,” Kepler told him. “I will make no secret of them.”9 After the first flush of Reformation, new ideas were no longer the fashion, and young Kepler the prodigy produced new ideas like sparks from a rocket. Denied health and strength and stature, he found his one compensation in his mind, forever questing, forever seeking the answers to the mysteries. As a boy, in his few spare hours he studied prosody and wrote his own comedies; he memorized the longest psalms in the Bible, just because they were the longest. His poems, he said, were mostly word games, acrostics, anagrams, and griphens. He loved paradoxes. Night after night, this intense, small dark-haired boy sat by the fire with the family Bible in his lap, his finger tracing out the lines, his mouth silently moving with the words, shoving each line into his memory.

  This intensity carried over into school, into his study, his prayers, and his battles. When he fought with his classmates, he meant everything he said. He was always in control of his words, and when his words burned, he meant them to. Perhaps this was why in later life he berated himself so for his quick rages, why one minute he was searin
g and vicious and the next apologetic. He was, though he never admitted it, a haughty genius as a young man, with that blind and simple arrogance of the young. Every day, he practiced in his life what he practiced in his science—he attacked, he ridiculed, he challenged his opponents as he waged war on the world. His violent tempers were gradually reformed, though they plagued him from time to time throughout his life, and where he once demanded, he later offered. He was more the Christian gentleman when he left the seminary than when he entered.10

  FROM KEPLER’S ASTRONOMIA NOVA 1609

  When, for the first time in my life, I tasted the sweetness of philosophy, I was taken by a forceful passion for it in general, not yet for astronomy in particular. I had a certain talent, and it was not hard for me to comprehend the geometrical and astronomical concepts, supported by figures, numbers, and relationships sufficient for educational standards. But those were necessary exercises and nothing that would have revealed a very strong inclination toward astronomy.

  Since I was supported by the Duke of Württemberg, I had to watch my fellow students often bristle out of love for their homeland as the duke, upon request, sent them to foreign countries. I was stronger and decided early, wherever I was to be sent, to follow willingly. My first task was an astronomical exercise, and I was actually sent there [to Graz] by order of the faculty. The distance didn’t bother me, as I have said I condemned this fear in others, but rather the unexpected and disdainful type of task and also my limited education in this area of philosophy. So I tackled it more supported by spirit than by science and promised myself not to abstain from my right to a way of life that appeared brighter.

  IV

  Taken by a Forceful Passion