by Dava Sobel
From conversations sustained over their long intimacy, Rheticus composed the only authorized biography of his teacher. Giese commended this prose portrait of Copernicus, but, unfortunately, Rheticus never published it, and the text disappeared.
However much Rheticus feared for his safety or suffered other anguish during the days and nights he spent in Varmia, he comforted himself with the pleasures of the new astronomy. “This and other like sports of Nature,” he reported, “often bring me great solace in the fluctuating vicissitudes of my fortunes, and gently soothe my troubled mind.”
In August 1540, several months after the First Account appeared, the expert printer Petreius penned an open letter to Rheticus and published it as an appendix to an astrology text he issued. Petreius hailed Rheticus for having traveled “to the farthest corner of Europe” to find Copernicus, and for writing such a “splendid description” of his system. “Although he does not follow the common system by which these arts are taught in the schools, nevertheless I consider it a glorious treasure if some day through your urging his observations will be imparted to us, as we hope will come to pass.” This encouragement was tantamount to an imprimatur from Petreius. A preeminent press—the leading printer in Nuremberg—stood ready to publish On the Revolutions.
Copernicus, however, had not yet committed himself to publication, but only to teaching Rheticus the intricacies of his theory. He devoted considerable time to instructing and sheltering his new disciple, while still shouldering his various administrative duties for the chapter. In September 1540, he registered with Rome his official request for a coadjutor. He was sixty- seven years old, and wished to see his young Danzig relative Jan Loitz, a boy of twelve, groomed to assume his canonry.
As part of the campaign to win Albrecht’s protection of Rheticus, Copernicus had offered to make his medical acumen available to the duke on demand. Albrecht found occasion to test this promise in April of 1541, when he wrote to say that “Almighty Sempiternal God is inflicting on one of my counselors and subordinates an affliction and severe illness which does not get better.” That same day, April 6, Albrecht also alerted the Varmia Chapter to the situation, in the expectation they would excuse Copernicus to make a house call. The chapter consented on April 8, expressing all the canons’ sympathy and announcing that Copernicus, “without any troublesome excuse, at his advanced old age,” would gladly comply.
Copernicus left immediately for Königsberg to do Albrecht’s bidding. Rheticus went along, as he could hardly remain in Frauenburg without his teacher—or pass up the opportunity to meet his royal patron. Soon after Duke Albrecht received them, he informed the chapter that Copernicus would need to stay a long while by the sick counselor’s bedside, “recalling that it is quite Christian and praiseworthy in such a case to act as a fellow-sufferer.” During the three weeks Copernicus tended to the invalid, he conferred by mail with the king’s physician in Krakow. Neither doctor could do much to soothe the patient, but at least he lived, and Albrecht felt thankful for that. Meanwhile Rheticus and Albrecht explored their mutual interests, which included mathematics, maps, and mapmaking.
Letters from Germany awaited both Rheticus and Copernicus when they got back to Frauenburg in May. Andreas Osiander had written to each of them individually, answering their requests for his advice. Osiander’s standing as both a theologian and an amateur mathematician—and a friend of the printer Petreius—uniquely qualified him to consult on how to publish Copernicus’s book without offending religious or Aristotelian sensibilities. To Copernicus, he suggested writing an introduction to make the point that mathematical hypotheses “are not articles of faith but the basis of computation; so that even if they are false it does not matter, provided that they reproduce exactly the phenomena of the motions.”
To Rheticus, he wrote: “The Peripatetics and theologians will be readily placated if they hear that there can be different hypotheses for the same apparent motion; that the present hypotheses are brought forward, not because they are in reality true, but because they regulate the computation of the apparent and combined motion as conveniently as may be; that it is possible for someone else to devise different hypotheses; that one man may conceive a suitable system, and another a more suitable, while both systems produce the same phenomena of motion; that each and every man is at liberty to devise more convenient hypotheses; and that if he succeeds, he is to be congratulated. In this way they will be diverted from stern defense and attracted by the charm of inquiry; first their antagonism will disappear, then they will seek the truth in vain by their own devices, and go over to the opinion of the author.”
A reprint of the popular First Account came out in Basel in 1541. This version prominently displayed Rheticus’s name on the title page. It also included an introduction by an old family friend of his, the physician Achilles Pirmin Gasser, predicting that the “contrary” sounding content would eventually establish “a true system of astronomy.” Although the reprint reached out to a wider audience of mathematicians, its real target seems to have been Copernicus himself—to erode the last shred of his reluctance to publish On the Revolutions. Gasser prophesied that support for the First Account would prompt “a greater stream of requests” to reach the author of “that rare and almost divine work (whose contents are here adumbrated),” thus “imploring him to allow the delivery of his whole work to us by means of the persistence, effort, and tireless diligence of my friend.”
The stream of requests indeed flowed swiftly. Even Bishop Dantiscus received an importuning letter from abroad—from Gemma Frisius, the polymath and instrument maker he had met in the Low Countries during his days as a diplomat. “Urania seems to have a new residence there with you, and raised up new worshippers who are about to offer us a new Earth, a new Sun, new stars, indeed a whole new world,” Gemma wrote. “I am filled with desire to see this business brought to fruition. And everywhere there are more than a few erudite men whose minds desire it no less than I do.” Dantiscus, inured by now to the Rheticus-Copernicus collaboration, dropped his air of grudging forbearance and finally got behind their project in earnest. In June of 1541, after meeting personally with Copernicus in Braunsberg, Dantiscus composed verses to be used as a foreword for the work in progress.
“I have received your Most Reverend Lordship’s very gracious and quite friendly letter,” Copernicus acknowledged. “Together with it you did not disdain to transmit also a truly elegant and relevant epigram for the reader of my book.” Copernicus promised to place the poem “in the forefront of my work, provided that the work is worthy to deserve being so highly embellished by your Most Reverend Lordship. Yet people who know more than I do, and to whom I should listen, say over and over again that my work is not negligible.” Even as he conferred with Rheticus throughout the summer to further revise and expand the text, he still felt qualms about publishing.
The bishop’s rhapsody undoubtedly loses much in translation, but says in part:
These writings show you the way to the heavens,
If you want to grasp with your mind the boundaries
Where the very beautiful universe expands its immense spaces,
Or the region of the heavens where the planets wander,
And the changes which their perpetual courses undergo …
Rheticus, a sometime poet himself and member of a poets’ circle in Wittenberg, resisted comment. With the bishop at last in his corner, he continued to court the duke. In August 1541 he sent Albrecht a copy of a booklet he had written about mapmaking, in German, called Chorography. The next day he sent another gift—most likely a gnomon, or shadow-casting instrument for gauging the length of days—along with a letter that begged a favor. The time had come for him to head home to Wittenberg, and he was not at all sure what sort of welcome awaited him there. A word from the duke would guarantee his reinstatement on the faculty, and also buy him time to see Copernicus’s book through production. Albrecht obligingly dictated a letter on September I to be sent to the Elector of Sax
ony, John the Magnanimous, with a copy to the university administration.
“Highborn prince, dear affectionate uncle and brother-in-law,” Albrecht called John. “Our especially beloved Georg Joachim Rheticus, professor of mathematics in Wittenberg, spent some time reputably and well here in these lands of Prussia. He also pursued his science of astronomy etc. in the same manner with divine grace and help. … Accordingly, it is our friendly request to Your Highness that in recognition of his skill, ability, and value, you may wish to validate and confirm him in the aforementioned professorship which he formerly held in Wittenberg. You may also wish graciously to allow and permit him to betake himself for a time, without interruption of his professor’s wages, for the sake of carrying out his intended work in the place where he decided to have his book printed. For our sake also, you may wish to show and evince to him all the gracious, beneficial good will, of which we have no doubt.”
Thus armed, Rheticus packed up a fair copy of Copernicus’s manuscript and said farewell to his teacher. Each knew he would never see the other again, and their emotions at parting probably blended grief with a measure of relief.
“Upon my departure,” Rheticus later remembered, “the great old man solemnly charged me to carry on and finish what he, prevented by old age and impending death, was unable to complete by himself.” In another context he wrote, “There has been no greater human happiness than my relationship with so excellent a man and scholar as he.”
When Rheticus arrived back in Wittenberg in October, the university immediately made him dean of the Faculty of Arts. This was probably as thankless a job then as now, and it burdened him with responsibilities that impeded his publishing agenda. He also acquired a new epithet, “Joachim Heliopolitanus,” or “one who comes from the City of the Sun.” Less a compliment than a mild condemnation of his adopted cosmology, the title clicked with an anti-Copernican comment Martin Luther purportedly dropped at lunch one day.
“So it goes now,” the great Reformer was overheard to remark. “Whoever wants to be clever must agree with nothing that others esteem. He must do something of his own. This is what that fellow does who wishes to turn the whole of astronomy upside down. Even in these things that are thrown into disorder I believe the Holy Scriptures, for Joshua commanded the Sun to stand still and not the Earth.” Another diner recalled Luther’s branding Copernicus a “fool,” and perhaps he did use that word, though all the “Table Talk” is hearsay. Melanchthon, on the other hand, wrote a letter in October 1541 that expressed his annoyance with “the Polish astronomer who moves the Earth and immobilizes the Sun.”
Between teaching duties and presiding at graduation ceremonies in February and April, Rheticus could not break away to take Copernicus’s manuscript to Nuremberg. Perhaps out of frustration, he selected two chapters treating technical aspects of geometry, called them On the Sides and Angles of Triangles, and published them in Wittenberg in 1542 with full credit to “the most illustrious and highly learned Mr. Nicolaus Copernicus.” At the opening of this book, he included—or rather, unloaded—the poem by Dantiscus, without attribution.
Not till early May 1542, after his term as dean ended, did Rheticus arrive in Nuremberg to deliver the bulk of the copied manuscript to Petreius. Printing commenced immediately. By the end of the month Rheticus had already corrected the first two signatures of eight pages each. In August, with progress well under way, he reflected on his Frauenburg adventure: “I regret neither the expense, nor the long journey, nor any of the other hardship. Rather, I feel I have reaped a great reward, namely that I, a rather daring youth, compelled this venerable man to share his ideas sooner in this discipline with the whole world. And all learned minds will join in my assessment of these theories as soon as the books we now have in press in Nuremberg are published.”
Chapter 8
On the Revolutions of the Heavenly Spheres
I confess that I shall expound many things differently from my predecessors, although I shall do so thanks to them, and with their aid, for it was they who first opened the road of inquiry into these very questions.
—FROM COPERNICUS’s INTRODUCTION TO BOOK I,
On the Revolutions of the Heavenly Spheres, 1543
Alone again with his fears of ridicule after Rheticus left, Copernicus fussed over his original manuscript. He jotted notes in the margins regarding a few new thoughts and corrections. He felt grave misgivings about the Mercury sections in Books V and VI. Even the observations Rheticus had brought from Schöner proved largely useless in constraining Mercury’s orbit to his system, and Copernicus wound up with a clumsy adaptation of Ptolemy’s model for the innermost planet.
In mid-June 1542 Pope Paul III approved the choice of young Jan Loitz as Copernicus’s coadjutor. The news, in the form of a papal writ, did not reach Varmia for many months, however, and in the interim Copernicus drafted a long letter to His Holiness on a different matter. Although he clearly addressed this letter to Pope Paul at the Vatican, he sent the final draft to Rheticus, care of Petreius in Nuremberg, to serve as the dedication for On the Revolutions.
“I can readily imagine, Holy Father,” he began, “that as soon as some people hear how in this volume, which I have written about the revolutions of the spheres of the universe, I ascribe certain motions to the terrestrial globe, they will immediately shout to have me and my opinion hooted off the stage.” His reluctance to publish had never fully subsided. Even now, he avowed, he had agreed to publish his work only at the repeated urging of insistent friends.
“They exhorted me no longer to refuse, on account of the fear which I felt, to make my work available for the general use of students of astronomy. The crazier my doctrine of the Earth’s motion now appeared to most people, their argument ran, so much the more admiration and thanks would it gain after the publication of my writings dispelled the fog of absurdity by most luminous proofs.”
Copernicus nowhere recorded the circumstances of his decision to dedicate his book to Pope Paul. No notes from Giese, Dantiscus, or any other dignitaries so much as hint as to how the idea came about, or how they obtained permission from the papal curia. His Holiness Paul III, né Alessandro Farnese, possessed no personal knowledge of mathematics himself, but expressed his interest in the uses of that science through the employment of a full-time, high-profile astrologer, Luca Gaurico. In 1534, as thanks to Gaurico for predicting Paul’s ascent to the throne of St. Peter, the new pope invited the favored astrologer to Rome and made him a bishop.
Copernicus credited Paul with at least a partial understanding of the motions of the heavenly spheres. In the dedication letter, he walked the Holy Father quickly through the unsatisfying homocentrics, eccentrics, and epicycles that had failed to produce “the structure of the universe and the true symmetry of its parts.”
“After long reflection,” he continued, “I began to be annoyed that the movements of the world machine, created for our sake by the best and most systematic Artisan of all, were not understood with greater certainty by the philosophers.” Copernicus had circumvented the schools of astronomy, he said, to reread all of philosophy. In the pages of Cicero and Plutarch, he had found references to those few thinkers who dared to move the Earth “against the traditional opinion of astronomers and almost against common sense.” (He still knew nothing of the Earth-moving plan of Aristarchus, which had not yet been reported to Latin audiences.)
Alessandro Farnese, elected Pope Paul III in 1534, in a painting by Titian.
“Therefore I too began to consider the mobility of the Earth. And even though the idea seemed absurd, nevertheless I knew that others before me had been granted the freedom to imagine.”
Thus liberated, he had correlated all the heavenly motions, as confirmed in the present volume, the contents of which he summarized before laying the work at the pope’s feet.
“In order that the educated and uneducated alike may see that I do not run away from judgment, I have preferred dedicating these results of my nocturnal study
to Your Holiness rather than to anyone else. For even in this very remote corner of the Earth where I live, you are considered the highest authority by virtue of the loftiness of your office and your love for all literature and even of mathematics.”
With that as preamble, he came to the real need for papal protection: “Perhaps there will be babblers who claim to be judges of astronomy although completely ignorant of the subject and, badly distorting some passage of Scripture to their purpose, will dare to find fault with my undertaking and censure it.” He and Rheticus had often discussed this possibility with Giese. They anticipated how Joshua’s command for the Sun to stand still might be hurled at Copernicus to prove the Sun’s motion and thereby destroy his whole theoretical edifice. Or criticism could wrap itself in Psalm 93’s proclamation that the foundations of the Earth remain forever unmoved—or Ecclesiastes’ account of how the Sun moves from sunrise to sunset and then hastens back to its rising place. Against the likelihood of such a biblical backlash, Rheticus had prepared a tract in which he rectified Holy Scripture with the Copernican ideal, but he had not yet published it. Even if Rheticus’s defense did appear in print, it could never approach the power of a single word from the pope.
“Astronomy is written for astronomers,” Copernicus asserted at the end of the dedication letter, for the simple reason that they alone could follow the mathematical proofs. That self-same audience of astronomers would recall the efforts of Leo X and the Lateran Council to reform the ecclesiastical calendar. They would remember how the attempt had failed for lack of adequate measurement of “the lengths of the year and month and the motions of the Sun and Moon.” Ever since that time, Copernicus said, “I have directed my attention to a more precise study of these topics. But what I have accomplished in this regard, I leave to the judgment of Your Holiness in particular and of all other learned astronomers. And lest I appear to promise more about the usefulness of this volume than I can fulfill, I now turn to the work itself.”
