A More Perfect Heaven

by Dava Sobel

  —JOHANNES KEPLER, Astronomia nova, 1609

  (TRANSLATED FROM THE LATIN BY WILLIAM H. DONAHUE)

  Chapter 7

  The First Account

  It is also clearer than sunlight that the sphere which carries the Earth is rightly called the Great Sphere. If generals have received the surname “Great” on account of successful exploits in war or conquests of peoples, surely this circle deserved to have that august name applied to it. For almost alone it makes us share in the laws of the celestial state, corrects all the errors of the motions, and restores to its rank this most beautiful part of philosophy.

  —GEORG JOACHIM RHETICUS, FROM THE First Account, 1540

  No one knows what the brilliant, fervent young Rheticus said when he accosted the elderly, beleaguered Copernicus in Frauenburg. It is safe to assume he did not laugh at the idea of the Earth in motion. And maybe that was enough to make Copernicus open his long-shelved manuscript, and also his heart, to the visitor who became his only student. Rheticus’s enthusiasm for astronomy leapt the barriers of age, outlook, and religious difference that might well have separated the two men. As Rheticus recalled years later of their time together, “Driven by youthful curiosity … I longed to enter as it were into the inner sanctum of the stars. Consequently, in the course of this research I sometimes became downright quarrelsome with that best and greatest of men, Copernicus. But still he would take delight in the honest desire of my mind, and with a gentle hand he continued to discipline and encourage me.”

  Nor does anyone know how Rheticus’s presence in Frauenburg escaped the wrath—or even the notice—of Bishop Dantiscus. Whether Copernicus intentionally hid the youth at first, or merely concealed his full identity, he soon hustled him out of town.

  As Rheticus explained the situation later in a letter to a friend, “I had a slight illness, and, on the honorable invitation of the Most Reverend Tiedemann Giese, bishop of Kulm, I went with my teacher to Löbau and there rested from my studies for several weeks.” Once outside Varmia, Rheticus was safe from religious persecution. The peace-loving Giese, who had long prodded Copernicus to publish his theory, must have been ecstatic to learn of their visitor’s ties to a respected printer of scientific texts. For Rheticus had brought as gifts three volumes bound in white pigskin, containing an assemblage of five important astronomy titles, three of which had been set in type and ornamented by the eminent printer Johannes Petreius of Nuremberg.

  By summer’s end in 1539, Rheticus had learned enough from Copernicus to write an informed summary of his thesis. He framed this précis as a letter to another mentor, Johann Schöner, a widely respected astrologer, cartographer, and globe maker in Nuremberg—and presumably the person who referred Rheticus to Copernicus in the first place.

  “To the illustrious Johann Schöner, as to his own revered father, G. Joachim Rheticus sends his greetings,” the report began. “On May 14th I wrote you a letter from Posen in which I informed you that I had undertaken a journey to Prussia, and I promised to declare, as soon as I could, whether the actuality answered to report and to my own expectation.” He then explained how his “illness” had diverted him to Kulm for a time. After ten weeks of concentration, however, he was ready to “set forth, as briefly and clearly as I can, the opinions of my teacher on the topics which I have studied.”

  Rheticus may have read a copy of the Brief Sketch in Schöner’s library before visiting Copernicus, or he could have come with only a vague notion of the new cosmology. Now he found himself one of two or at most three people in the world to have paged through the complete draft version of On the Revolutions.

  The erudite Johann Schöner of Nuremberg, as painted by Lucas Cranach the Elder.

  “My teacher has written a work of six books,” he told Schöner, “in which, in imitation of Ptolemy, he has embraced the whole of astronomy, stating and proving individual propositions mathematically and by the geometrical method.” Ticking off the topics covered in each of the six parts, Rheticus said nothing of what is today considered the work‘s most salient feature. Indeed, he remained strangely silent about the motion of the Earth until page nineteen of his protracted description. Perhaps he knew Schöner and other readers would find a moving Earth ludicrous, and so he avoided mention of it for as long as he could. Or, equally likely, he judged a different aspect of Copernicus‘s work to be more important, and therefore gave it precedence. This was the explanation of the eighth sphere, or how the daily spin of the heavens drifted slowly backward over time—the subject of Copernicus’s spar with Werner. Rheticus presented Copernicus’s numerical results without saying that the starry sphere remained stationary in the Copernican model. He concentrated instead on cyclic time patterns Copernicus had identified through observations of the Sun and stars. To Rheticus’s mind, these long cycles coincided with turning points in world history, and he seized on an interpretation that he believed Schöner would appreciate:

  “We see that all kingdoms have had their beginnings when the center of the eccentric [here Rheticus refers to long-term changes in the Sun’s apparent position] was at some special point on the small circle. Thus, when the eccentricity of the Sun was at its maximum, the Roman government became a monarchy; as the eccentricity decreased, Rome too declined, as though aging, and then fell. When the eccentricity reached the boundary and quadrant of mean value, the Mohammedan faith was established; another great empire came into being and increased very rapidly, like the change in the eccentricity. A hundred years hence, when the eccentricity will be at its minimum, this empire too will complete its period. In our time it is at its pinnacle from which equally swiftly, God willing, it will fall with a mighty crash. We look forward to the coming of our Lord Jesus Christ when the center of the eccentric reaches the other boundary of mean value, for it was in that position at the creation of the world.”

  Surely Rheticus had found exactly what he had come for: Copernicus’s carefully developed mathematical treatise offered a firm new footing for the most momentous predictions of astrology. Nothing could extend Rheticus’s own longevity, of course, but in his short life he believed he might yet shape a destiny, and maybe even achieve glory, by bringing Copernicus out of the shadows.

  “A boundless kingdom in astronomy has God granted to my learned teacher,” Rheticus interrupted his narrative to exclaim. “May he, as its ruler, deign to govern, guard, and increase it, to the restoration of astronomic truth. Amen.”

  Next Rheticus boasted to Schöner how Copernicus had resolved the Moon’s motion without stretching or shrinking the lunar diameter. One could talk easily enough about the Moon’s going around the Earth without referring to the Earth’s motion. Only when he brought up the motions of the other planets did Rheticus finally concede that the center of the universe might shift in the new picture. And, almost in the same breath, he defended the switch: “Indeed, there is something divine in the circumstance that a sure understanding of celestial phenomena must depend on the regular and uniform motions of the terrestrial globe alone.”

  The road ahead—meaning the struggle to convince others to accept Copernicus’s wisdom—would admittedly be difficult. But Rheticus had committed himself to this course and expected Schöner to do the same.

  “Hence you agree, I feel, that the results to which the observations and the evidence of heaven itself lead us again and again must be accepted, and that every difficulty must be faced and overcome with God as our guide and mathematics and tireless study as our companions.” Even Ptolemy, Rheticus claimed, “were he permitted to return to life,” would applaud this “sound science of celestial phenomena.”

  Rheticus whipped himself into a frenzy of enthusiasm as he appraised Copernicus’s labors. He found it almost inconceivable to contemplate the burden of effort that had allowed his teacher to take all the disparate phenomena of astronomy and link them “most nobly together, as by a golden chain.” Over the remainder of his sixty-six-page report (twice as long as the Brief Sketch and the Letter Against Werner com
bined), Rheticus directly addressed Schöner a dozen times, as though to shake him awake to the new reality: “To offer you some taste of this matter, most learned Schöner,” “Let me in passing call your attention, most learned Schöner,” “But that you may the more readily grasp all these ideas, most learned Schöner,” and so on, leading up to a final impassioned appeal:

  “Most illustrious and most learned Schöner, whom I shall always revere like a father, it now remains for you to receive this work of mine, such as it is, kindly and favorably. For although I am not unaware what burden my shoulders can carry and what burden they refuse to carry, nevertheless your unparalleled and, so to say, paternal affection for me has impelled me to enter this heaven not at all fearfully and to report everything to you to the best of my ability. May Almighty and Most Merciful God, I pray, deem my venture worthy of turning out well, and may He enable me to conduct the work I have undertaken along the right road to the proposed goal.”

  The letter, had it been merely a letter, might have ended there. But Giese, together with Copernicus, hoped to see Rheticus’s report published as a test of acceptability for the heliocentric theory, and therefore the ending necessarily took a political turn. In his effusive concluding pages, Rheticus sang the praises of Prussia.

  “You might say that the buildings and the fortifications are palaces and shrines of Apollo; that the gardens, the fields, and the entire region are the delight of Venus, so that it could be called, not undeservedly, Rhodes. What is more, Prussia is the daughter of Venus, as is clear if you examine either the fertility of the soil or the beauty and charm of the whole land.”

  Rheticus extolled the Prussian forests teeming with stag, doe, bear, boar, aurochs, elk, and bison; the beehives, orchards, and plains; the rabbit warrens and birdhouses; and the lakes, ponds, and springs that he deemed “the fisheries of the gods.” He cited the famous personages of the land as well, bowing respectfully to “the illustrious prince, Albrecht, Duke of Prussia” and that “eloquent and wise Bishop, the Most Reverend Johann Dantiscus.”

  Sometime between mid-May 1539, when Rheticus arrived in Varmia, and September 23, the date he concluded his report, Bishop Dantiscus likely discovered his presence through his network of informants. But he took no legal action. Perhaps Giese convinced Dantiscus of the visiting professor’s value in publicizing Canon Copernicus’s life work as a credit to Varmia. Or perhaps the Rheticus affair paled, in the bishop’s eyes, in comparison to the continuing “trysts” between Copernicus and Anna Schilling. She had never left town, according to the gossip Dantiscus heard from his closest ally in Frauenburg, Provost Pawel Plotowski. Here Giese in fact interceded by letter, imploring Dantiscus not to believe such groundless rumors. Further aspersions from Plotowski, however, continued to inflame Dantiscus’s anger.

  “At his old age,” Dantiscus complained of Copernicus in reply to Giese, “almost at the end of his allotted time, he is still said to receive his concubine frequently in furtive assignations.” Dantiscus beseeched Giese to remonstrate with Copernicus on his behalf, and to speak as though he, Giese, were dispensing his own good advice. Reporting back to Dantiscus on September 12, 1539, Giese said he had reprimanded Copernicus as promised, but that his good friend denied all of Plotowski’s pernicious charges.

  Winding up the final pages of his report, Rheticus crafted an elaborate thank you to Giese for his goodness and kindness, crediting the prelate with having served as Copernicus’s inspiration.

  “His Reverence mastered with complete devotion the set of virtues and doctrine, required of a bishop by Paul. He realized that it would be of no small importance to the glory of Christ if there existed a proper calendar of events in the Church and a correct theory and explanation of the motions. He did not cease urging my teacher, whose accomplishments and insight he had known for many years, to take up this problem, until he persuaded him to do so.” This scenario, though otherwise undocumented, suggests that Giese became muse to Copernicus even before the heliocentric idea was born.

  “Since my teacher was social by nature,” Rheticus continued, “and saw that the scientific world also stood in need of an improvement of the motions, he readily yielded to the entreaties of his friend, the reverend prelate. He promised that he would draw up astronomical tables with new rules and that if his work had any value he would not keep it from the world. … But he had long been aware that in their own right the observations in a certain way required hypotheses which would overturn the ideas concerning the order of the motions and spheres that had hitherto been discussed and promulgated and that were commonly accepted and believed to be true; moreover, the required hypotheses would contradict our senses.”

  On the horns of that dilemma, Rheticus said, Copernicus had decided to “compose tables with accurate rules but no proofs.” In other words, he would offer instructions for deriving planetary positions without mentioning his mind-boggling rationale. Rheticus doubtless knew from his weeks in their company that Giese and Copernicus had reached just such a compromise in 1535. Their friend Bernard Wapowski, recipient of the Letter Against Werner, visited them in Frauenburg in the autumn of that year, while Copernicus was completing an abbreviated treatise with a complete set of tables. Wapowski took a copy of this almanac with him back to Krakow. In October he tried, through his royal connections, to have the work printed in Vienna, but the negotiations ended in November, with Wapowski’s death.

  “Then His Reverence pointed out that such a work would be an incomplete gift to the world,” Rheticus went on, “unless my teacher set forth the reasons for his tables and also included, in imitation of Ptolemy, the system or theory and the foundations and proofs upon which he relied.” Thus Copernicus’s book had come to be. Though the author later put it aside, Giese had never stopped agitating for its release.

  “By these and many other contentions, as I learned from friends familiar with the entire affair, the learned prelate won from my teacher a promise to permit scholars and posterity to pass judgment on his work. For this reason men of good will and students of mathematics will be deeply grateful with me to His Reverence, the bishop of Kulm, for presenting this achievement to the world.”

  The other patron Rheticus esteemed loudly at the end of his report was Johann of Werden, the mayor of Danzig. “When he heard about my studies from certain friends, he did not disdain to greet me, undistinguished though I am, and to invite me to meet him before I left Prussia. When I so informed my teacher, he rejoiced for my sake and drew such a picture of the man that I realized I was being invited by Homer’s Achilles, as it were. For besides his distinction in the arts of war and peace, with the favor of the muses he also cultivates music. By its sweet harmony he refreshes and inspires his spirit to undergo and to endure the burdens of office.”

  One would think Rheticus had laid on his hyperbole a bit thick, but his gushing got the First Account into the Danzig civic printing office, where it was published early in 1540. As soon as the first three sheets came off the press in March, a friend and classmate of Rheticus sent them to Philip Melanchthon in Wittenberg—evidence of what Rheticus, absent from the university for nearly two years now, had been doing with his time.

  The title page of the First Account did not identify its author by name, but only as “a certain youth.”

  TO THE MOST ILLUSTRIOUS GENTLEMAN

  MR. JOHANN SCHÖNER, CONCERNING

  THE BOOKS OF THE REVOLUTIONS

  Of the most learned Gentleman and

  Most distinguished Mathematician,

  The revered Doctor Mr. Nicolaus

  Copernicus of Torun, Canon of

  Varmia, By a certain youth

  Most zealous for

  Mathematics—

  A FIRST ACCOUNT.

  Rheticus, who had cleverly inserted his full name into the salutation in the First Account’s first paragraph, could afford to be modest on the title page. He sent copies of the finished book to friends and acquaintances who had helped him along the way, beginning natur
ally with Schöner.

  Among the early plaudits to reach Rheticus in reply was a congratulatory note from Andreas Osiander, the Lutheran theologian who had initiated Duke Albrecht’s conversion. As other excited letters from scholars also greeted the First Account, Rheticus realized he was about to become famous. He could return to Saxony a hero.

  From Giese’s perspective, however, the publication of the First Account merely paved the way for On the Revolutions. He wanted the talented Rheticus to stay on in Frauenburg and help Copernicus prepare his lengthy manuscript for publication. Weary of finessing Rheticus’s illegal residence in Varmia, Giese wished to find him a new sponsor—especially after April 15, 1540, when Bishop Dantiscus enforced the king’s anti-Protestant decree by recalling all Varmian subjects “from the poisoned places of heretical Lutheranism,” and calling also for the destruction of Lutheran books or songs in anyone’s possession anywhere in Varmia. On April 23, Giese dispatched a copy of the First Account to Duke Albrecht at his palace in Königsberg. Writing in German to introduce the little Latin treatise, Giese asked “that Your Princely Eminence might look graciously upon this highly learned guest on account of his great knowledge and skill, and grant him your gracious protection.”

  Rheticus apparently came under the duke’s aegis soon afterward, because he remained in residence. Except for a brief return visit to Wittenberg to give two lectures late in 1540, Rheticus continued working alongside Copernicus. Together they reorganized and rewrote several sections of On the Revolutions. They reviewed all the demonstrations describing the planetary motions and the directions for deriving specific positions in celestial latitude and longitude. Rheticus likely assisted Copernicus’s measurement of the partial solar eclipse that occurred over Frauenburg on April 7, 1540. Sixteen months later, when another partial solar eclipse visited the region on August 21, 1541—the fourth and last one that Copernicus observed—Rheticus was still at his side.