SOURCE: "Tycho Brahe's German Treatise on the Comet of 1577: A Study in Science and Politics," in Isis, Vol. 70, No. 251, March, 1979, pp. 110-40.

I

Tycho Brahe was born into a family with strong political traditions. His father was governor of Aalborg castle and fief, then of the key stronghold of Helsingborg on the Sound, and he ended his days as a Councillor of the Realm. Both of Tycho's grandfathers, all four of his great-grandfathers, and many of his more distant ancestors had also been members of this sovereign Council (Rigsråd) which elected kings, declared wars, made peace, and in short functioned as the core of an aristocratic oligarchical regime for much of the fifteenth and sixteenth centuries.¹ In Tycho's own day, two of his brothers and one of his brothers-in-law sat in the Council, and both of these brothers also sat in Regency Councils.² Tycho's great-great-grandfather and his great-uncle had both been Lord Marshal (Rigsmarsk), and another great-uncle, as well as one of Tycho's brothers, was Statholder of Skåne.³ On his mother's side Tycho descended from the house of Vasa, and he was thus a kinsman to the monarchs of Sweden and Poland in his own day.⁴ Many of kinsmen, including his favorite uncle, had been in the Danish diplomatic service.⁵ His foster mother, then his mother, served as maitresse de la cour to Queen Sophie.⁶ Finally, the great Danish statesman and virtual ruler of the realm in Tycho's youth, Peter Oxe, was a brother of Tycho's foster mother.⁷

In his younger days, however, Tycho revealed a decided reluctance to become involved in politics. As a young lad in Leipzig, he developed a distaste for the study of law and even took to ridiculing juridical pedantry in Latin verse.⁸ This was not the attitude that made a diplomat or a governor of great fiefs. Later on, when his university education was finished, he did put in the term of service at court which was all but obligatory for a member of his family returning from studies abroad, but when King Frederick II, late in the year 1575, asked him to state his own requirements in terms of fiefs and honors, this bewildering young courtier simply failed to reply.⁹ To close friends Tycho confessed that he was planning to emigrate in order to avoid just such obligations and to devote himself wholly to astronomy and various arcane studies. "I did not want to take possession of any of the castles our benevolent king so graciously offered me," he wrote to one intimate friend in Copenhagen, " … I am displeased with society here, customary forms and the whole rubbish…. Among people of my own class … I waste much time."¹⁰ To Petrus Severinus, who had just become the king's physician in ordinary, he wrote of the perils of courtly life: "For the court accepts one and all with flattery and benevolence, but sends them away unsatisfied and against their will."¹¹

Tycho's devotion to astronomy and related disciplines seemed eccentric and even harmful to one of his social standing. Great aristocrats might dabble in such matters or even display considerable erudition, but they seldom turned down fiefs and honors because of their studies. When Tycho did so, it had apparently caused the king, Peter Oxe, and some of Tycho's uncles and other kinsmen to speculate concerning a suitable employment for his gifts. In 1568 he had been promised the next vacant canonry of Roskilde cathedral, a sinecure suitable to the dignity of a nobleman.¹² Peter Oxe had encouraged him to publish a manuscript he had written on the new star of 1572, either under his own name or an anagram.¹³ In 1574 friends like Charles de Danzay and Johannes Pratensis, and finally even King Frederick himself, requested that Tycho gratify the wishes of aristocratic students at the University of Copenhagen by lecturing on the mathematical disciplines. This was the background for an oration which he delivered in the presence of the French legate and the entire university community in early September of 1574.¹⁴

II

The French legate, Charles de Danzay, was a Protestant who enjoyed a great deal of popularity at the Danish court, where he had been accredited for over twenty years. In earlier days Danzay had wielded considerable influence in the direction of peace in the Baltic region, working at the same time to keep Denmark from becoming too friendly toward England to the jeopardy of Franco-Scottish relations. He played a large part in mediating the Peace of Stettin in 1570.¹⁵ Two years later, however, it had been his painful duty to inform the Danish court of the murder of Admiral Coligny "and others" on the night of St. Bartholomew. From that time, Franco-Danish relations deteriorated ever so gradually.¹⁶ Danzay's privy dispatches were sometimes critical of the "excessive liberties" of the Danish aristocracy, and he was particularly wary of Peter Oxe, who had been in the service of the Duchess of Lorraine before coming home to Denmark in 1566.¹⁷ This charming and sophisticated diplomat had quickly become a confidant of the young Tycho Brahe, who had returned home from several years of foreign study at the end of 1571.¹⁸

Tycho's lectures of 1574-1575 did raise some ticklish problems of decorum. He held no university degrees, and in any case it would not have been appropriate for him as a nobleman to ascend the cathedra of an ordinary university lecture hall. A request, however, not from ordinary academicians but from noblemen studying at the university, advocated in addition by the king himself, elevated the whole matter from an academic plane to the appropriate aristocratic social level where Tycho's lectures were perfectly acceptable. The oration was delivered before an audience of doctors, professors, students, and distinguished guests, including the French legate.

Tycho's oration traced the origins of astronomy, the noblest of all disciplines, from geometry and arithmetic, descending in a genealogy of wisdom from Seth to Abraham, the Egyptians, Timocharus and Hipparchus, Ptolemy, Albetegnius, Alfonso the Wise, and Copernicus. From astronomy, Tycho progressed to astrology and made it the principal subject, but the spirit which permeated the oration was that of humanism, and its major theme was the dignity of man. Tycho spoke with erudition and with poetic power, merging the ideals of Pico and Ficino with Melanchthon's concept of the rational free will. He described the macrocosm in detail as a human environment charged with Paracelsian energy, where "There is no herb so insignificant, no mineral nor metal, no object, no animalcule so vile that it is not endowed with some special and particular virtue."¹⁹ Perhaps Ramus also made his contribution to Tycho's thought, as when the young orator drew a distinction between the realm of natural philosophy and that of God's "arcane council of which no creature is participant."²⁰ Most striking of all, however, was the pervasive Coperpican spirit of Tycho's characterization of astronomy.²¹

This Copernicanism set the tone for the series of lectures which followed during the winter semester of 1574-1575. Since others lectured regularly on spherical astronomy, Tycho limited his lectures to planetary theory, explaining the method of calculating planetary motions from the Prutenic tables and describing the theory according to which these tables had been computed, but departing from Copernican cosmology by referring everything to an immobile earth.²² He lectured in this manner on the fixed stars, the sun, and the moon, but broke off before dealing with the planets. Caspar Peucer had lectured on Copernicus in a similar vein at Wittenberg in 1559, and his lectures had suddenly appeared in print in three different editions during the years 1568-1573.²³ Tycho would not accept the approach of Peucer, whom he criticized along with Dasipodius for mixing Copernicus and Ptolemy together. Tycho himself held exclusively to the mathematical models of Copernicus, though he transposed them to fit a geostatic assumption. Thus, in the words of Kristian P. Moesgaard, it is evident that "Copernicus and Copernican astronomy was introduced in Denmark in a thorough and competent way by an expert."²⁴

III

The mere fact that Tycho's oration was delivered in the French legation may have reflected to the honor of Charles de Danzay and the monarch he represented. In the actual content of the oration, however, there was nothing specifically political in the modern sense, though the careful sixteenth-century auditor may have been able to detect political overtones in Tycho's long description of planetary virtues and their effects upon the microcosm, or in similar passages.

At a dinner following the talk, as Tycho stood by, Danzay remarked lightly to Professor Niels Hemmingsen that Tycho had not only attacked the other faculties for their disbelief in astrology but had gone so far as to do the same to the theologians. For his own part Danzay thought that astrological predictions were a hindrance to the Evangelical teaching. Tycho said he replied that astrology was not a threat if it held to its proper sphere and did not get involved in politics.²⁵ Throughout this whole conversation there seem to be undertones that only these two friends were able to appreciate fully. Danzay certainly knew full well, for example, that part of Tycho's oration was a loosely veiled critique of Hemmingsen's writing on astrology. One can only guess at the implications of Tycho's reply.

Niels Hemmingsen, the senior professor of theology at the University of Copenhagen, was Denmark's brightest theological light in those years. Like virtually all of his colleagues, he was a disciple of Philipp Melanchthon and had spent the crucial part of his student days in Wittenberg. The Philippists shared Melanchthon's humanist orientation and also his tolerance and his irenic striving for religious harmony. Their theology included a symbolical interpretation of the Eucharist which caused other Lutherans to suspect them of crypto-Calvinism, but this was coupled with a strong emphasis upon free will which contradicted the doctrine of predestination. Like Melanchthon, they associated free will with reason and consequently became strong advocates of education. Hemmingsen had been the foremost spokesman of Danish Philippism for a good twenty years.²⁶ In the present context, however, it is significant that he did differ with Melanchthon on at least one point: whereas Melanchthon had conceived of man as a microcosm and had been a dedicated believer in astrological influences, Luther had scoffed at this, and a good many of Melanchthon's own disciples, including Hemmingsen, also rejected astrology.²⁷ Tycho's attack upon Hemmingsen's disparagement of astrology should not be allowed to obscure the fact that they both stood in the same theological camp. Tycho was also a Philippist, though of course a layman, and he shared Melanchthon's belief in astrological influences. Following Tycho's oration, Hemmingsen had replied to Danzay's remarks by saying that he would tolerate Tycho's belief in astrology on two conditions: if complete freedom of action were left to God and free will to men. Tycho was more than willing to concede them both.²⁸

IV

When Tycho delivered his oration, Philippism had reigned supreme in the Danish church for almost a generation, humane and mild, while the thunder of German theological controversy rumbled in the distance. In the spring of 1575, as Tycho was concluding his lectures on Copernican astronomy, that controversy cast a mighty bolt against Niels Hemmingsen. It came from Saxony.

Elector Augustus of Saxony, a brother-in-law of King Frederick II, had spent a part of the summer of 1572 in Copenhagen and elsewhere in Denmark helping to celebrate the Danish king's wedding. Of course he had brought his Saxon theologians along, and they had passed much of the time with their Danish colleagues. Elector Augustus was a man who took great pride in his role as protector of the holy places of Lutheranism. Apparently he was not aware that crypto-Calvinism was rife all around him. Early in 1574, however, he discovered it with a vengeance and cast all of his leading theologians into prison, including Melanchthon's sonin-law, Caspar Peucer, who was a friend of Tycho even though they were not always in complete agreement. The next spring a Danish scholar, Master Jørgen Dybvad, came into Denmark from Saxony with a personal letter from the Elector to King Frederick. Crypto-Calvinism had been discovered in Saxony; the culprits had defended themselves by pleading the precedent of Denmark; this evil must be purged. Elector Augustus was particularly aware of Hemmingsen's recent work, Syntagma institutionum christianarum, which had appeared simultaneously with an anonymous work of the same tenor in Saxony, thus giving away the "plot" which had been hatched in Denmark during the summer of 1572.²⁹

It was true that this work of Hemmingsen's had presented a thoroughly Calvinist interpretation of the Eucharist, though without actually mentioning Calvin. This had already caused no little embarrassment to the Danish crown. The missive from Saxony, and Jørgen Dybvad's oral elaborations, brought action. Early on the morning of June 15, 1575, all endowed professors of the University of Copenhagen, all pastors of Copenhagen churches, and the bishop of Roskilde were summoned in a body to the Castle of Copenhagen to answer the Elector's charges. They met before a commission of three great lords: Peter Oxe, Chancellor Niels Kaas, and Councillor Jørgen Rosenkrantz. Hemmingsen defended what he described as the unity of the Danish church against attacks from abroad. German theologians are manifold, he said, and they all leap like cooks to please the palate of their lord. If we hearken to them all, we shall have utter confusion in Denmark, instead of unity of belief and religious practice. This was an argument of no little weight, given the political instincts of his inquisitors. Rosenkrantz remained harsh in his queries, but Peter Oxe concluded the hearing with the words, spoken to Hemmingsen, "No misfortune will come over you for my sake."³⁰

Within a few months, however, the great statesman Peter Oxe was dead. Hemmingsen now moved under a cloud. Most Danish theologians stood by him, and Tycho's close friend Anders Sørensen Vedel translated one of Hemmingsen's vernacular works into Latin to demonstrate abroad that it was harmless to orthodoxy.³¹ But Hemmingsen's enemies were relentless. On the recommendation of Elector Augustus, Jørgen Dybvad was appointed extraordinary professor of theology in Copenhagen. In April of 1576 Saxon pressures upon the Danish crown forced Hemmingsen to sign a formal retraction of his offensive views in Syntagma institutionum christianarum.³² All Danish theologians were forbidden to dispute concerning the Eucharist. In May of 1576 Danish censorship was tightened, while a conference assembled in Germany to define a common Lutheran confession and especially to differentiate Lutheran belief from Calvinism. Elector Augustus twice sent the resulting confessional statement, the Torgau Book, to King Frederick, requesting that the Danish theologians debate it, but the king refused, saying that he would not disrupt the unimpeachably Lutheran consensus that prevailed within his kingdoms since Hemmingsen's retraction. Dano-Saxon relations cooled markedly as a result of this royal attitude, but the pressures upon Hemmingsen did not diminish.³³ He was a much embattled man in the spring of 1577, when he seems to have turned to Tycho Brahe for support.

On May 18, 1577, Hemmingsen proposed in the Consistory of the University of Copenhagen that Tycho Brahe be elected rector of the university for the forthcoming twelvemonth.³⁴ This office was normally held by a professor, elected annually by his colleagues in rotation among the four faculties. The rector was the actual administrative and ceremonial leader of the academic community, ultimately responsible to the chancellor of the university, who was always the Royal Chancellor.³⁵ Tycho's lectures on astronomy two years earlier might have served to establish an identity with the university and to clothe this extraordinary election with some semblance of logic, but his astronomical eloquence was hardly sufficient motivation. In the spring of 1577 Hemmingsen craved strong support, not only within the inner sancta of government, in order to dampen the king's reaction to pressures from Saxony, but also within the university itself, where only a resolute rector could curb the pernicious energy of J0rgen Dybvad. As a nobleman, Tycho Brahe radiated an authority no middle-class professor could deny; yet he declined the nomination, pleading that he was too busy with his building on the isle of Hven.³⁶ Once again, he seemed to draw back from political involvement.

V

Tycho had withdrawn even more dramatically during the year 1575. In the midst of his lectures on Copernican astronomy, coming into a considerable inheritance, he had simply departed Denmark on an extended tour of the Continent.³⁷ He had earlier spent some eight years abroad, residing in Leipzig, Rostock, Wittenberg, Basel, and Augsburg, and he now visited old acquaintances in many of these places. More important politically, however, were the new contacts he established, which were all with states that opposed the policy of confessional polarization advocated by Saxony.

Tycho went first to Cassel and spent a week at the court of William IV, Landgrave of Hesse-Cassel, who shared a fascination with astronomy and related arts. A close personal rapport developed which was renewed in later years.³⁸ In Venice, Tycho found admittance to the learned gatherings and "academies" that flourished among the patricians of the republic and the scholars from nearby Padua, and he participated in many an erudite discourse. There is no evidence that he helped to introduce the Copemican philosophy to these circles, but he did establish contacts that were maintained for many years.³⁹ Finally, in Regensburg, Tycho attended the coronation as King of the Romans of the future Emperor Rudolf II. Once again he penetrated into the inner circles, and he established a particularly close contact with the court physician, Thaddeus Hagecius, who presented him a manuscript of Copernicus' Commentariolus.⁴⁰

It was Basel, however, that caught Tycho's fancy more than any other place, and his reasons bespoke a striving for peace, wisdom, and universal harmony. Tycho spoke of the city's favorable location for a "student interested in learned subjects, or for one who loves Apollonian tranquility and the Muses," a bridge between creeds and cultures, "near to Italy, France and Germany."⁴¹ This striving preyed upon his mind when he returned home to Denmark toward the end of 1575.

VI

Tycho has left a dramatic letter, written three days after the event, which tells how his future plans were suddenly changed by a summons from King Frederick II which reached him at Knutstorp manor on February 11, 1576. He hastened to the royal hunting lodge of Ibstrup and was shown into the privy chamber, where he conversed with the king in private. The Landgrave of Hesse-Cassel had written and admonished King Frederick not to overlook the talents of this young nobleman, and the king had heard indirectly that Tycho was planning to emigrate. All of this, and Tycho's reluctance to accept a royal command, had been on the king's mind recently, when he had been residing at the castle of Elsinore, "'and when I looked out through a window, I spied the little isle of Hven…,"⁴² One of Tycho's uncles had once mentioned that the isle appealed to Tycho. The king now offered it to him in lifetime fee. Tycho was profoundly moved by this proposal, originating, as he felt, with the king himself. He deliberated for seven days, and he consulted in secret with his two French friends Danzay and Pratensis; then he accepted.⁴³

The king immediately granted him 500 dalers per annum from the Sound Dues collected in Elsinore, a sum that seems to have been equal to around three quarters of the annual income from Tycho's patrimony.⁴⁴ Three months later, Tycho was granted the isle of Hven in fee, quit and free of all dues and services to the crown, for the duration of his lifetime.⁴⁵ On the same day he was granted an additional 400 dalers to begin construction of a suitable residence on the isle.⁴⁶ In August of 1577 he was granted another fief with extensive tracts of forest, apparently in order to fire the brick kilns, and later the alchemical furnaces, of Hven.⁴⁷ In 1578 he was granted a minor fief in Skåne and a larger one in Norway to augment his income, and in 1579 he received his canonry in the chapter of Roskilde.⁴⁸ These endowments finally enticed Tycho Brahe into royal service and drew him directly into the realm of politics.

VII

Perhaps the royal appetite had been whetted by a short treatise in humanist format which Tycho had published, with Peter Oxe's encouragement, just three years before he entered the royal Danish service. The treatise dealt with the new star, or supernova, of 1572. One brief section had attempted to analyze the astrological effects of the star. Tycho's conclusions had been ones with rather direct political implications: he had predicted that the star would induce great and unusual effects, originating in northern regions such as Russia, Livonia, Finland, Sweden, or Norway, bringing serious tumults, spreading throughout Europe, followed by "a new condition in kingdoms, different from the earlier, and likewise a different order of religious conditions and laws."⁴⁹ Yet the forecast was cryptic and unclear. It did not attempt to determine when the effects would occur, and it concluded with the remark that Tycho also knew of a "truer and more secret" astrology which he was not willing to divulge in writing.⁵⁰ In short, this treatise might be enticing to a believer in astrology, but it could not be of much use to practical statesmen like Peter Oxe and King Frederick II in planning future policies.

VIII

The obligations that fell upon Tycho's shoulders, in return for the lavish royal patronage that followed the year 1576, seem surprisingly light. He served as a sort of royal consultant on astronomical and astrological matters, compiled a horoscope upon the birth of each royal son, replied to royal inquiries like the one in 1578 concerning rumors that another new star had appeared, and he apparently supplied the royal family with an almanac or prognostication in manuscript annually.⁵¹ He also fabricated and repaired instruments for the crown, worked on various cartographic and iconographie projects, and supplied Queen Sophie with alchemical equipment.⁵² On one occasion Tycho, upon the request of King Frederick, had one of his disciples write a book on weather prognostication.⁵³ In later years Tycho entertained princely and royal guests to Denmark with tours of the isle of Hven,⁵⁴ where he main tained a sort of royal academy and advanced institute.⁵⁵ He served as a versatile royal consultant on many matters in the realm of empirical natural philosophy, but he was still free to devote much time to his own research.

In times of cosmic crisis, however, his counsel was quickly summoned, which happened within a year after Tycho became a vassal of the Danish king. The event which gave Tycho the first opportunity to offer his particular kind of counsel to his liege lord was the birth of a royal son and heir, the future King Christian IV, on April 12, 1577. This birth had been predicted the year before by a mermaid who appeared out of the sea and foresaw a glorious future under the coming prince.⁵⁶ Tycho Brahe was called upon to be more specific. On July 1, 1577, he presented a detailed horoscope, in Latin with a German summary, which naturally concentrated on the mature years of the prince.⁵⁷ Its political implications were manifold, but they all applied to a period some thirty to fifty years in the future. The horoscope did not provide guidelines to royal policy in the immediate future any more than did the earlier treatise on the new star of 1572.

The second cosmic event of 1577 occurred around the time of Martinmas, when a great comet appeared in the constellation Capricorn. It was seen in Danish court circles as an omen of awful significance. For Tycho its most immediate effect was to call forth a dangerous rival among Danish astrologers. This time the rival was no mermaid from the briny deep but a professor from the king's own University of Copenhagen, none other than Jørgen Dybvad.

IX

Jørgen Dybvad had been at Sorø Abbey on St. Martin's day, November 11, 1577. On the evening of that day, he had first seen the great comet in the skies. He later applied 'Ali ibn Ridwan's method and calculated that the comet had arisen the previous evening at the time of the new moon but had been hidden at first by dark weather and rain.⁵⁸

There were others at Sorø Abbey on that feast of St. Martin in 1577. One of them was King Frederick II;⁵⁹ another was Abbot Ivar Bertelsen; still another may have been the king's physician, Petrus Severinus. The sources do not tell whether these men discussed the comet on the evening it appeared, but such a dramatic and ominous event could hardly have failed to be among the topics of conversation around the abbot's table that evening.

Ivar Bertelsen, the abbot of Sorø, knew something about astronomy. He had once been a man of restless and choleric temper like Dybvad, plagued by visions of righteousness and doom. Violent changes in fortune had buffeted him since student days as Melanchthon's disciple in Wittenberg, and for three years he had been a ragged prisoner, incarcerated in the very abbey of which he was now the Lutheran abbot. He spent his latter days as a great royal favorite, married to a young noblewoman, with a flock of sons and daughters who were destined for distinguished careers.⁶⁰

In 1561, as a young professor of rhetoric in Copenhagen, Bertelsen had published a pamphlet which predicted the apocalypse in phrases of poetic fury, describing how the Lord had let the winds and weather and the very fires of the firmament preach over Denmark to show His wrath.⁶¹ This same apocalyptic theme was taken up by Dybvad in analyzing the effects of the comet of Martinmas, 1577.

Within five weeks of the first sighting, Dybvad had produced a pamphlet on the comet. The fact that it was written in the vernacular and dedicated to King Frederick is enough to establish that it had political as well as scientific aims. In the dedication Dybvad asserted that the "terrible great comet" was one of manifold signs which revealed that "the day of the Lord, according to His promise, is at hand." Besides the comet, he cited a profusion of prophetic, chronological, and astral evidence, including the new star of 1572, which he accepted as a celestial phenomenon. He then proceeded to list almost fifty previous sightings of comets over the course of more than two thousand years as evidence for the assertion that comets are always followed by great changes in politics and weather. Finally, he asserted that the comet of 1577 would bring a cold, snow-laden winter, followed by a hot, dry summer, with tempests, crop failure, and "gruesome treachery in affairs of religion."⁶² Dybvad expected these effects to be felt in many lands:

Hungary may well fear highly of the Turk. Hispania will feel a hard rod. Cologne on the Rhine will not be left out. Saxony, Thüringen, Hesse, Steiermark, the Brandenburg lands, Augsburg, Kostnitz, Cleve, Berg, Ghent, Mecklenburg, Lithuania, must make ready for the effects of this comet, and especially for pestilence. Poland dare not be proud, for it must also drink of the cup, and it appears in particular, that the Muscovite or the Tartar will bring a sour visitation upon them…. Denmark, uplift thine eyes, shake off the sleep … look about thee, and mark, that this comet does also threaten thee with pestilence and dear times…. The Muscovite, Sweden, Walachia, Westphalia, Trent, Hamburg, Bremen, Salzburg, Calabria, Portugal, Alexandria, and many other realms and lands will also receive something of this comet's effects.⁶³

Dybvad predicted that "Great Lords" in particular would be affected by the comet, though it threatened not only mankind, but also "birds, fishes, and beasts of the field." He asserted at last that it was "greatly necessary, that we seriously turn unto the LORD," and he concluded his treatise with a prayer for mercy and for divine protection over Denmark and the Danish royal family.⁶⁴

X

Martinmas had been overcast on the isle of Hven. Two days later, on the afternoon of November 13, 1577, in clear weather, Tycho Brahe had been out by his fish ponds catching fish for the evening meal. As the sun went down, sometime before five o'clock, Tycho noticed a bright star in the western sky over Sjælland. He knew it could not be Venus, because Venus was a morning star at that time, and it was too bright to be Saturn. Tycho watched as the dusk turned to darkness. The star held its position, and a long ruddy tail gradually grew visible, stretching in the opposite direction from the point of sunset. This was a comet, the first Tycho had ever seen.⁶⁵ He was about thirty-one years old at the time.

Tycho went immediately to his new manor house of Uraniborg. He took forth some folio sheets of paper, folded them into a little notebook in quarto format, took forth his radius, later also his quadrants, and began to record his observations of the comet. The next day he wrote to Petrus Severinus, asking him to arrange affairs with the king so that he could observe without being disturbed. Of course he knew that the king would be anxious to hear his counsel concerning the comet, but he wanted to study the phenomenon carefully before venturing a prognosis. He also asked Severinus to send him any observations he might have taken of the comet.⁶⁶

For the next two and a half months, whenever the sky was clear, Tycho observed the comet and entered his observations in the little notebook, which has survived,⁶⁷ though a bit tattered by weather and use. On the night of November 13 Tycho sketched the comet….

As the observations began to fill the little notebook, Tycho began to ponder their significance. Aristotle had taught, nearly two thousand years earlier, that comets occurred in the upper atmosphere, like lightning and meteors.⁶⁸ Tycho studied the parallax of the comet, however, and concluded that it was located far beyond those regions and even beyond the moon, in the celestial regions which Aristotle had described as the realm of eternal, unchanging circular motion, where nothing new could ever occur. In the back of his little notebook Tycho made two rough sketches illustrating the parallax of the comet…. They show the comet to be about one third of the way from earth to the stars.

Tycho was not particularly disturbed to discover that this comet violated Aristotle's teaching. In the first place, he was skeptical of Aristotle's sharp distinction between the celestial and terrestrial regions and was apparently more inclined to accept the teaching of Paracelsus—that the whole universe was a living, dynamic cosmos, subject to growth and diminution in due time.⁶⁹ What is more, Tycho had already observed one earlier creation in the upper heavens and had accepted it as such: the new star of 1572. Consequently the problem as he saw it was, not to explain the celestial location of the comet, but to discover precisely where it fit in among the other bodies of the celestial spheres.

Tycho had observed, among other things, that the tail of the comet always pointed away from the sun. He explained this by assuming that the comet rotated around the sun. In the back of his little notebook he made two rough sketches illustrating this arrangement in terms of the laws of perspective, showing the real and apparent locations of the comet's tail as observed from earth.

Tycho now turned to the question of the comet's location with respect to the other celestial bodies. His heliocentric orbit for the comet indicates that he still favored the theories of Copernicus. He assumed that the planets also rotated around the sun, and his next step was to determine the location of the comet among them. He made two more rough sketches …, the first showing the orbits of Mercury and Venus around the sun, with the orbit of the comet outside that of Venus. This sketch also reveals that Tycho was still referring everything to an immobile earth, as he had done in his lectures of 1574–1575.

Gradually, Tycho was coming to grips with the comet in the sky. Now he must bring its cosmic message down to earth. Early in the year 1578 Tycho wrote a brief vernacular manuscript on the comet, a work with immediate political implications. In that brief manuscript Tycho launched an attack upon the astrological conclusions of Jørgen Dybvad, though he refrained from mentioning him by name.

XI

Tycho and his rival represented two different social strata: compared with Tycho's aristocracy, Dybvad was of prosperous yeoman stock, but he was a man of intense ambition. His political instincts were sound. In those early years they led him to curry the favor of those who wielded power. In the face of great majesty, such as that of the comet of 1577, his solution was to cower and pray, but in other circumstances he used other methods, dedicating a prolific flow of writings to influential courtiers and learned noblemen, and ingratiating himself at court with his reports from Saxony.⁷⁰

These tactics had their reward. Early in 1578 a rather inert professor in Copenhagen was exiled to the chapter of Lund, and Dybvad was appointed to the chair of mathematics thus vacated. He was also granted a monopoly on the publication of almanacs. The other professors conceived these changes as infringements upon their liberties and stubbornly resisted, but by the summer of 1578 they had been broken to the royal will.⁷¹ Dybvad, immune to the lack of cordiality among his colleagues, soundly entrenched in the royal favor and his tenured professorship of mathematics, began to cast ever more covetous eyes upon Professor Niels Hemmingsen's prestigious chair of theology.

Here was a dangerous rival for Tycho as well as for Hemmingsen. Dybvad had won the ear of the king, no less than Tycho had done. This fact went far to obviate Tycho's decided advantages of birth, wealth, social status, and kinship within the ruling oligarchy. So did the fact that their rivalry was caught up in a web of social, political, and intellectual issues, so that each of them acted, half unwittingly, as the spokesman for forces more powerful than himself. Tycho stood on the side of Hemmingsen and the Philippist tradition in the Danish church; in politics, he was closely allied to the great magnates who were the heirs of Peter Oxe; in foreign affairs, his ties were with the opponents of confessional militance.⁷² Dybvad, on the other hand, had been the very herald of the Saxon attack upon Hemmingsen; he was a royalist, certainly not a magnate, and he stood among those who worked for closer ties with more orthodox Lutherans.

Dybvad was a first-rate scholar. His writings on astronomy, meteorology, and mathematics revealed a tendency toward new, radically anti-Aristotelian patterns of thought.⁷³ He was the first Dane to publish a commentary on Copernicus,⁷⁴ and he was quite willing to accept the new star of 1572 as evidence of celestial mutability.⁷⁵ Observational astronomy, however, was not his strong point, and there is no evidence that he observed the comet of 1577 systematically. His astrology merged the Ptolemaic tradition with a strong sixteenth-century tradition of historical chronology, establishing a temporal cosmic scheme with overtones of apocalyptic violence, reminiscent of the Reformation era. Dybvad was a Hebrew scholar, but he does not seem to have used the caballa to interpret celestial events, and his denial of Democritus appears to derive from an aloofness toward the Pythagorean tradition in general.⁷⁶ The arena for their rivalry was not the con sistory of the university, for Tycho had rejected the office of rector which would have brought him into academic politics. It seems rather to have been the royal court itself.

XII

The ways in which late-sixteenth-century philosophers and astrologers related celestial occurrences to contemporary politics have been the subject of much scholarship in recent years. Frances Yates' work on the French monarchy is intriguing in the light of Tycho's French ties,⁷⁷ though she refrained from investigating the Danish connections in her book on the Rosicrucian movement.⁷⁸ French, Howell, and Yates have probed some of the celestial dimensions of Elizabethan politics.⁷⁹ Evans has established a new context for the later years of Tycho's life with his book on the court of Emperor Rudolf II.⁸⁰ This literature, supplemented by Hellman's classic study of treatises on the comet of 1577,⁸¹ establishes a general framework for the consideration of Tycho's brief vernacular manuscript on the comet of 1577.

This manuscript was discovered in two copies among the Tychonic papers in Vienna and was first published in 1922.⁸² A number of factors indicate that this treatise may have been Tycho's report to the Danish crown. The clear implication of Tycho's letter to Severinus is that he will present a confidential analysis of the comet to the king in due time. This manuscript is the only known contemporary account of that comet from Tycho's hand. The language is German, which Tycho also used in other manuscripts written expressly for the crown.⁸³ The form is a close parallel to Tycho's royal horoscopes. The manuscript exists in a revised and finished version, but it was never printed.⁸⁴ All of this is circumstantial evidence, but the chains of circumstance seem firmly linked.

Its contents are interesting from a cosmological as well as a political point of view. Tycho began the manuscript with a summary description of the cosmos, and he went on to establish the location, appearance, and effects of the comet within that framework. In the very first sentence he parenthetically rejected Aristotle's four elements in favor of three. As the manuscript progressed, its consistently anti-Aristotelian tone became more evident and it simultaneously began to infuse the geostatic world picture with new concepts derived from Paracelsus. The basic idea of three elements, rather than four, is a sign of this process. It became most explicit in Tycho's review of the historiography of cometary theory. He began with the Pythagoreans, showed how they were refuted by Aristotle, then used the evidence of the heavens themselves (in the form of the new star of 1572) to refute Aristotle, before concluding with the modern view of Paracelsus. Tycho presented this Paracelsian view as one that was consistent with Pythagorean thought and not inconsistent with the evidence of the new star. Later on in the manuscript he adopted the Paracelsian terminology of "pseudoplanet" to describe the comet. Tycho was also careful to give a precise description of color changes in the comet and its tail, which he may have seen as the signatures of some powerful cosmic alchemy. He did reject the more specifically mystical or spiritual aspects of Paracelsus, however, such as the existence of the Superior Penates, by applying a distinction which he may have derived from Ramus, between those things which can be known through the study of nature and those which cannot and therefore fall into the realm of theology. This was a crucial step: it allowed Tycho to strip away the Hermetic mysticism from Paracelsus' dynamic conception of the heavens and to merge it with the astronomical tradition of mathematical analysis. This freed Tycho of Aristotle and gave him a new, dynamic cosmological framework for his investigations.

Tycho dealt at length with physical questions such as the diameter and mass of the comet, its actual distance from earth, the length and physical nature of its tail. He derived its spatial location from its parallax. His ideas developed rapidly under the stimulus of these investigations, which seem to have been carried out during the early months of 1578. In the manuscript Tycho referred to "this year of '78," and he noted that he lost sight of the comet on January 26 of that year. Owen Gingerich has recently discovered a series of diagrams in Tycho's hand, derived from work done in January and February of 1578 and revealing that the comet of 1577 stimulated Tycho to work out various new models of Copernican planetary theory accommodated to an immobile earth.⁸⁵ These diagrams are closely related to the rougher sketches reproduced above, and to Tycho's vernacular manuscript on the comet.

With this in mind, it is interesting to notice the slight shifts in emphasis through successive versions of Tycho's draft manuscript on the comet. They indicate a progressively clearer commitment to the concept of Copernican theory accommodated to geocentricity.⁸⁶

I.⁸⁷

Therefore, I conclude that it was in the sphere of Venus, if one wants to follow the usual distribution of the celestial orbs. But if one prefers to accept as valid the opinion of various ancient philosophers and of Copernicus in our own time, that Mercury is next to the sun, and Venus around Mercury, both with the sun at the approximate center of their orbs, which reasoning is not entirely out of harmony with truth, even if the sun [several variant expressions struck in the MS] is not put to rest in the center of the universe as the hypotheses of Copernicus would have it.

II.⁸⁸

Therefore, I conclude that it was in the sphere of Venus, if one wants to follow the usual distribution of the celestial orbs. According to the opinion of various ancient philosophers and of Copernicus in our own time, they hold that Mercury comes after the sun, and Venus around Mercury, both with the sun at the approximate center of their orbs….

III.⁸⁹

Therefore, I conclude that it was in the sphere of Venus, but if one does not want to follow the usual distribution of the celestial orbs but would rather accept as valid the opinion of various ancient philosophers and of Copernicus in our own time, that Mercury has its orb around the sun, and Venus around Mercury, with the sun at the approximate center of their orbs, which reasoning is not entirely out of harmony with truth, even if the sun is not put to rest in the center of the universe as with the hypotheses of Copernicus….

While Tycho Brahe was thus pondering the shape of the universe and groping his way toward a new understanding of it, his royal patron must have been waiting impatiently. King Frederick believed in astrology, as Tycho did. He knew that this great comet was an omen of awful significance. He wanted to know its true astrological meaning in detail, so he could plan his spiritual affairs as well as the foreign and domestic policies of his realm.

The last half of Tycho's manuscript came to bear upon astrological analysis. He began by confuting those astrologers (like Dybvad) who associated the significance of comets with regular and predictable celestial events, because comets, as "new and supernatural" creations of God, actually worked in opposition to such "natural courses of the heavens." Then Tycho summarized the comet's effects. Like Dybvad and others, he predicted warfare, pestilence, and extremes of heat and cold; he also laid a particular emphasis upon changes in religion. His words were moderate, but their implications were startling. To a king raised on tales of the bloodshed and rebellion of the Reformation era, Tycho spoke of a forthcoming "great alteration and turmoil in the spiritual matters of religion, which will be something more than has hitherto been experienced." At the same time, he emphatically denied that the comet of 1577 or any other celestial sign presaged the apocalypse. Tycho thus threw down a direct challenge to the Dybvads and Bertelsens among Danish astronomers. In another brief, furious passage, he chastized "pseudoprophets … who have mounted too high in their arrogance, and have not wandered in divine wisdom," and he concluded that they "will be punished."

Tycho associated his prophecy of the new religion with such potent harbingers as the new star of 1572 and the great planetary conjunction in the beginning of Aries more than with the comet of 1577, the effects of which he saw as subsidiary to the greater cosmic events. He predicted that the alteration "may even bode more for the better of Christendom than for the worse," for it was possible that "the eternal Sabbath of all Creation is at hand" and would commence sometime during the forthcoming decade. Just what Tycho meant by this is difficult to say, but he was undoubtedly able to elaborate at length in confidential conversation. He may have had the astrologers' ominous year of 1588 in mind.⁹⁰ There are implications of cabalist influence and overtones of the "religion of the world." An urge for universal peace was certainly part of the expectation. There may also have been some association with a political schema of correspondences between terrestrial states and celestial bodies, such as that which associated "solar" effects with France, or "saturnine" with Spain. In any case, it was apparent that the apocalyptic violence of the Reformation era, still evident in Dybvad's treatise on the comet, was giving way in Tycho's mind to a more irenic and pacific millenarianism, with its roots in Philippism but charged with tremendous arcane significance as well.

There is no evidence that Tycho agreed with his many contemporaries who advocated magical solutions to political or cosmic problems.⁹¹ Tycho's response was that of a politically mature aristocrat, tempered by the cool rationality of Melanchthon. What Tycho urged was a rational exercise of the free will, leading to action which could moderate or control the predictable effects of the comet and other cosmic events. This was a response different from the labyrinthine operations of the Magus, and equally different from Dybvad's solution of anguished prayers for deliverance from divine wrath.

This consideration led Tycho to treat the comet's effects in a clearly political manner, so that they could be mitigated by appropriate policies. He did not sound a doomsday roll call of places and plagues, but rather he indicated three specific areas that would be affected by the comet. To the east of Denmark the comet would bring warfare and bloodshed to the Muscovites and Tartars in the years around 1579–1580, possibly even bringing the downfall of the tyrannical Ivan the Terrible by 1583. To the south it would cause trouble for the Spaniards, especially in the Netherlands and in the realm of religion, beginning "this year of '78," reaching a head in 1579–1580 and lasting till 1583. During these same years the comet would threaten Emperor Rudolf II and cause great disunity within the Holy Roman Empire, while Spanish machinations would pose a serious threat to the Saxon Circle, where King Frederick II had some of his best allies and where he himself was Duke of Holstein. These evil effects would finally be counteracted by some person arising under the sign of Libra: dignified, harmonious, rational, just, diplomatic, peace-loving, conciliatory, charming, tolerant, impartial, persuasive, honorable. Here was a prediction which could be translated directly into policy: oppose Spain in the Saxon Circle, aid the Dutch rebels, be prepared to benefit from disorder in Muscovy, but strive withal for harmony and peace.

XIII

The aim of this paper has been to probe the political, religious, and cosmological background of a single treatise by Tycho Brahe, written at a crucial time in his intellectual development. I have tried to show that his cosmological framework was not essentially Aristotelian but Paracelsian, though in a rationalized version developed by Tycho under the influence of thinkers like Severinus, Melanchthon, Niels Hemmingsen, and Ramus. This matter has really only been touched upon and needs further investigation. Tycho's method at this stage, as the text to follow will make quite clear, was a radical empiricism based upon mathematical analysis. His belief in astrology was genuine, though it was of a special kind, tempered by the Philippist theology with its strong emphasis upon rationality and freedom of the will. Finally, we have seen how Tycho used Copernican concepts, accommodated to a stable earth, during this period when he was groping his way toward a more satisfying planetary theory.

Besides these internal considerations, there has been an external dimension to the investigation. I have tried to place this treatise of Tycho Brahe in the context of Danish affairs as well as in a broader European intellectual and political framework. I have tried to demonstrate an affinity between Tycho Brahe, Philippism, and the foreign policy of peace based on alignment with the politique powers. Tycho Brahe was not an isolated figure, some tempest-torn Prospero on his isle of Hven, nor were his occasional references to plots and covert pressures the sign of paranoia. He was intimately involved in the affairs of his day, and those affairs were frequently complex and hard fought. Perhaps it would not be an overstatement to say that the party with which he was allied stood strong for the next two decades in Denmark, but when its power diminished, he fell. It will take more research, however, to verify such a statement. In any case, Tycho's work does take on new significance when seen in its social and political milieu as well as its specifically Danish intellectual context.⁹²

Notes

¹ Tycho's father was Otte Brahe; see Povl Engelstoft and Svend Dahl, eds., Dansk biografisk leksikon (hereafter cited as DBL), Vol. III (Copenhagen: Schultz, 1934), pp. 574-575. His grandfathers were Tyge Brahe and Claus Bille; see DBL, Vol. III, pp. 23-26, 583. His great-grandfathers were Axel Brahe (d. 1487), Jørgen Rud (DBL, Vol. XX [1941], pp. 286-287), Steen Basse Bille (DBL, Vol. III, pp. 50-51), and Jens Holgersen Ulfstand (DBL, Vol. XXIV [1943], pp. 496-497). On the Brahe family, see Albert Fabritius, "Brahe," Danmarks adels aarbog (hereafter cited DAA) (Copenhagen: Schultz, 1950), Pt. 2, pp. 3-32.

² Axel Brahe (d. 1616; DBL, Vol. III, pp. 564-565), Steen Brahe (DBL, Vol. III, pp. 580-582), and Christen Skeel (DAA, 1943, Pt. 2, pp. 99-100).

³ Claus Rønnow (DAA, 1913, p. 484); Eskild Gøye, married to Sidsel Brahe (DBL, Vol. VII [1936], pp. 132-133); Axel Brahe (d. 1551; DBL, Vol. III, pp. 563-564); and Axel Brahe (d. 1616).

⁴ Claus Bille was a second cousin of King Gustavus Vasa through his maternal grandmother, Birgitta Kristiernsdotter (Vasa), a sister of the king's grandfather.

⁵ Steen Bille; see DBL, Vol. III, pp. 51-52. See also Emil Marquard, Danske gesandter og gesandtskabspersonale indtil 1914 (Copenhagen: Munksgaard, 1952).

⁶ Inger Oxe was dronningens hofmesterinde 1572-1584; see DAA, 1907, p. 343. Beate Bille was dronningens hofmesterinde 1584-1592; see DAA, 1950, Pt. 2, p. 13. Danish noblewomen of the 16th century did not relinquish their maiden name upon marriage.

⁷ On Peter Oxe, see DBL, Vol. XVII (1939), pp. 547-562.

⁸ Wilhelm Norlind, Tycho Brahe. En levnadsteckning med nya bidrag belysande hans liv och verk (Lund: Gleerup, 1970), p. 17.

⁹ I. L. E. Dreyer, Ioannes Ráder and Eiler Nyström, eds., Tychonis Brahe Dani Opera Omnia (hereafter cited as TBDOO), Vol. VII (Copenhagen: Gyldendal, 1924), p. 26.

¹⁰Ibid., Vol. VII, p. 25.

¹¹Ibid., Vol. VII, p. 39.

¹²Ibid., Vol. XIV (1928), pp. 3-4.

¹³ J. L. E. Dreyer, Tycho Brahe. A Picture of Scientific Life and Work in the Sixteenth Century (Edinburgh: Adam & Charles Black, 1890; reprinted New York: Dover, 1963), p. 43.

¹⁴ Frances A. Yates has probed the relationships between French politics and intellectual life during this era in various works, including The French Academies of the Sixteenth Century (London: The Warburg Institute, 1947; reprinted Nendeln, Liechtenstein: Kraus, 1968); and Giordano Bruno and the Hermetic Tradition (New York: Vintage, 1969). At the University of Copenhagen there was no festive auditorium at that time; see WIlliam Norvin, Københavns universitet i reformationens og orthodoxiens tidsalder, Vol. I (Copenhagen: Gyldendal, 1937), pp. 243-245.

¹⁵ L. Laursen, Danmark-Norges traktater 1523-1750, Vol. II (Copenhagen: Gad, 1912), pp. 213-260. See also Holger Rørdam, "Return bello Svetico gestarum (1563-70) series et narratio succincta, autore Mag. Andrea Severini Velleio," Monumenta Historiae Daniae. Historiske kildeskrifter, Vol. II (Copenhagen: Gad, 1875), pp. 163-198. Holger Rørdam, "Charles de Danzay, fransk resident ved det danske hof," Historiske samlinger og studier, Vol. II (Copenhagen: Gad, 1898), pp. 269-283.

¹⁶ Rørdam, "Danzay," pp. 284, 319-324.

¹⁷Ibid., pp. 281, 289. C. F. Bricka, Indberetninger fra Charles de Dançay til det franske hof om forholdene i Norden 1567-1573 (Copenhagen: Reitzel, 1901), contains Danzay's dispatches; see pp. 12 and 15-18. On Peter Oxe, see Poul Colding, Studier i Danmarks politiske historie i slutningen af Christian III.s og begyndelsen af Frederik II.s tid (Copenhagen: Busck, 1939); see also Poul Colding, "Danmark-Lothringen 1565-66 og Peder Oxes hjemkomst," Historisk tidsskrift, 1944, 10th Ser., 6: 637-659.

¹⁸ Rørdam, "Danzay," pp. 293-297. Their earliest correspondence still extant is from 1576; see TBDOO, Vol. VII, p. 34, passim. Danzay was in Poland from the autumn of 1573 till August 1574, playing an important role in the Polish adventure of Henry of Anjou; see Rørdam, "Danzay," pp. 284-287.

¹⁹TBDOO, Vol. I (1913), p. 154, translation by Jeremiah Reedy. The oration, given on pp. 143-173, is treated at length in J.-S. Bailly, Histoire de l'astronomie moderne depuis la fondation de l'ecole d'Alexandrie jusqu 'à l'epoque de M.D.CC.XXX., Vol. I (Paris: Frères de Bure, 1779), pp. 429-442. See also Dreyer, Tycho. pp. 73-78, and Norlind, Tycho. pp. 53-63.

²⁰TBDOO, Vol. I, p. 154, translation by Jeremiah Reedy. On Ramism in Denmark, see William Norvin, "Petrus Ramus og Danmark," Lychnos, 1943, 97-110.

²¹TBDOO, Vol. I, pp. 147-150 et passim. Kristian Peder Moesgaard, "Copernican Influence on Tycho Brahe," in Jerzy Dobrzycki, ed., The Reception of Copernicus' Heliocentric Theory (Dordrecht, Holland/Boston: D. Reidel, 1972), pp. 31-33.

²²TBDOO, Vol. I, pp. 172-173. On the tradition of geostatic Copernicanism, see J. R. Christianson, "Copernicus and the Lutherans," Sixteenth Century Journal, 1973, 4, 2: 1-10; Robert S. Westman, "The Wittenberg Interpretation of the Copernican Theory," in Owen Gingerich, ed., The Nature of Scientific Discovery (Washington, D.C.: Smithsonian Institution Press, 1975), pp. 393-429 and discussion, pp. 430-457; and Robert S. Westman, "The Melanchthon Circle, Rheticus, and the Wittenberg Interpretation of the Copernican Theory," Isis, 1975, 66: 165-193.

²³ Ernst Zinner, Entstehung und Ausbreitung der coppernicanischen Lehre (Sitzungsberichte der Physikalischmedizinischen Societät zu Erlangen, LXXIV) (Erlangen: Mencke, 1943), p. 273, see also p. 294. Reinhold's approach was also in this spirit; see Alexandre Birkenmajer, "Le commentaire inedit d'Erasme Reinhold sur le De revolutionibus de Nicolas Copernic," La science au seizième siècle (Paris: Hermann, 1960), pp. 168-178.

²⁴ Moesgaard, "Copernican Influence," p. 32.

²⁵TBDOO, Vol. I, p. 172.

²⁶ Bjørn Kornerup, Den danske kirkes historie, Vol. IV (Copenhagen: Gyldendal, 1959), pp. 69-73, 138-141 et passim.

²⁷ Karl Hartfelder, Philipp Melanchthon als Preceptor Germaniae (Berlin: Hofmann, 1899; reprinted Nieuwkoop: De Graaf, 1964), pp. 190-197. On Niels Hemmingsen, see Oluf Friis, Den danske litteraturs historie, Vol. I (Copenhagen: Hirschsprung, 1945), pp. 353-356.

²⁸TBDOO, Vol. I, p. 172.

²⁹ Holger Fr. Rørdam, Kjøbenhavns universitets historie fra 1537 til 1621, Vol. II (Copenhagen: Bianco Luno, 1872), pp. 123-139. Kornerup, Den danske kirkes historie, Vol. IV, pp. 131-147, is essentially dependent upon Rørdam.

³⁰ Holger Fr. Rørdam, "Bidrag til de filippistiske bevægelsers og til D. Niels Hemmingsens historie," Kirkehistoriske samlinger, 1867-68, 6: 297-300.

³¹ C. F. Wegener, Historiske eflerretninger om Anders Sørensen Vedel [Copenhagen, 1851], pp. 75-78. It was also during these years that a great many of Hemmingsen's works were translated into English: see Lauritz Nielsen, Dansk bibliografi 1551-1600 (Copenhagen: Gyldendal, 1933; hereafter cited as LN), Nos. 810, 814, 839, 868, 869, 893-897, 928, and 929; for Latin editions printed in London see Nos. 809, 813, 819, 848, and 849.

³² Røardam, Universitets historie, Vol. II, pp. 141-151. On Dybvad, see DBL, Vol. VI (1935), pp. 151-153; Holger Fr. Rørdam, "Efterretninger om Jørgen og Christoffer Dybvad," Danske magazin, 1873, 4th Ser., 2: 107-108; and Kristian Peder Moesgaard, "How Copernicanism took Root in Denmark and Norway," in Dobrzycki, ed., Reception, pp. 117-119.

³³ Rørdam, Universitets historie, Vol. II, pp. 152-160.

³⁴TBDOO, Vol. XIV, p. 6. See also Rørdam, Universitets historie, Vol. II, pp. 170-175.

³⁵ Niels Kaas, who was chancellor in 1573-1594, was a former pupil of Hemmingsen and had resided for four of his student years in Hemmingsen's household; see Rørdam, Universitets historie, Vol. II, pp. 373-396.

³⁶TBDOO, Vol. VII, pp. 45-46.

³⁷ Tycho's father died in 1571, leaving an extensive estate. See his manuscript cadaster in Rigsarkivet, Copenhagen—Privatarkiv: Otte Tygesen Brahe (d. 1571), "Otte Brahes Jordebog, 17. april 1570." Of this estate I estimate that Tycho inherited something over 100 copyhold farms comprising one half of Knutstorp manor minus his mother's widow's portion, worth roughly 650 dalers per annum. See also J. R. Christianson, "Tycho Brahe and Patronage of Science 1576-1597," American Philosophical Society, Year Book 1972 (Philadelphia: American Philosophical Society, 1973), pp. 572-573.

³⁸ See their correspondence in TBDOO, Vol. VI (1919), pp. 31-54, et passim.

³⁹ Norlind, Tycho, pp. 66-68, also discusses Tycho's later connections with G. F. Sagredo. On Tycho's contacts with G. A. Magini, either directly or through Tengnagel, Gellius, and Kepler, see Antonio Favaro, Carteggio inedito di Ticone Brahe, Giovanni Keplero e de altri celebri astronomi e matematici dei secoli XVI. e XVII. con Giovanni Antonio Magini tratto dall' Archivio Malvezzi de' Medici in Bologna (Bologna: Zanichelli, 1886).

⁴⁰TBDOO, Vol. VII, p. 37. Norlind, Tycho, p. 343.

⁴¹TBDOO, Vol. VII, p. 25.

⁴²Ibid., Vol. VII, p. 27.

⁴³Ibid., Vol. VII, p. 28. Pratensis was bom in Denmark, but his father, Philippe du Pre, had come into Denmark in 1514 with King Christian II's bride, Isabella of Habsburg, a sister of Emperor Charles V. Pratensis spent his student years abroad and held his medical degree from a French university. See Rørdam, Universitets historie, Vol. II, pp. 598-607.

⁴⁴TBDOO, Vol. XIV, pp. 4-5; see also pp. 19-20, 23, and 102.

⁴⁵Ibid., Vol. XIV, p. 5; see also pp. 7, 15-19, 26-27, 41-43, 49, 51-52, 98-105, 125-128, 184-189, and 245.

⁴⁶Ibid., Vol. XIV, pp. 5-6.

⁴⁷ Kullan; see ibid., Vol. XIV, pp. 6-7, 12-14, 21-29, 49-50, and J. R. Christianson, "Addenda to Tychonis Brahe Opera Omnia tomus XIV," Centaurus, 1972, 16: 231-235, 241-242.

⁴⁸ Farms in Skåne, see TBDOO, Vol. XIV, pp. 8-9; see also Kullan. Nordfjord in Norway, see TBDOO, Vol. XIV, pp. 7-11, 14-17, 19, 32, 34-38, 48-49, 54, 62-63, 67, 97-98, 130, 139, and Christianson, "Addenda," p. 243. Chapel of the Magi, see TBDOO, Vol. XIV, pp. 3-4, 12-14, 24-25, 35-36, 55-60, 63-66, 68-71, 91 et seq., 106, and Christianson, "Addenda," pp. 240-241.

⁴⁹TBDOO, Vol. I, pp. 30-34. There is also a facsimile edition edited by F. R. Friis, Tychonis Brahe Dani die XXIV Octobris A.D. MDCI Defuncti Operum Primitias De Nova Stella (Copenhagen: Ioergensen, 1901); see sig. [D2v]-E3. In the year 1632 this prophecy was widely associated with King Gustavus Adolphus.

⁵⁰TBDOO, Vol. I, p. 34.

⁵¹Ibid., Vol. XIV, pp. 9 and 37-39.

⁵²Ibid., Vol. XIV, pp. 28, 30-31, 48, and 61-62.

⁵³ J. R. Christianson, "Tycho Brahe's Cosmology from the Astrologia of 1591," Isis, 1968, 59: 313.

⁵⁴ These included King James VI of Scotland in 1590; Duke Heinrich Julius of Braunschweig-Wolfenbüttel in 1590 (both married daughters of King Frederick II); Queen Sophie of Denmark and her parents, Duke Ulrich of Mecklenburg-Güstrow and Duchess Elizabeth, in 1586; and King Christian IV of Denmark in 1592; see Dreyer, Tycho, pp. 138-139, 202-205 and 214-217. There were also innumerable foreign diplomats among Tycho's visitors to Hven; see Harald Ilsøe, "Gesandtskaber som kulturformidlende faktor. Forbindelser mellem Danmark og England-Skotland o. 1580-1607," Historisk tidsskrift, 1962, 11th Ser. 6: 574-600.

See also Tycho's meteorological journal, which also records many visitors to Hven, in TBDOO, Vol. IX, pp. 39-146.

⁵⁵ Norlind, Tycho, pp. 93-94, 101-103, and 168-170.

⁵⁶ Troels-Lund, "Christian den fjerdes fødsel og daab," Historiske fortællinger. Tider og tanker, Vol. I (Copenhagen: Gyldendal, 1910), pp. 10-13 and 113-119.

⁵⁷TBDOO, Vol. I, pp. 179-208. The German version, which was the one actually intended to be read by the parents, is omitted from all three of Tycho's royal horoscopes in TBDOO; see also Vol. I, pp. 209-280. The importance of the German section is emphasized in the manuscript horoscope for Prince Hans, where it is the only section in Tycho's own autograph (the Latin section was delegated to an amanuensis); see Dreyer, Tycho, p. 153, and MS, Det kongelige bibliotek, Gammel kongelig samling 1823, 4°.

⁵⁸ Jørgen Christoffersen Dybvad, En nyttig Vnderuissning Om den COMET, som dette Aar 1577. in Nouembrj først haffuer ladet sig see (Copenhagen: Laurentz Benedicht, 1578), sig. D-[D^v]. For the 1577 edition of this work, see LN No. 553 (the 1578 edition is ZJVNo. 554). See also C. Doris Hellman, The Comet of 1577: Its Place in the History of Astronomy (New York: Columbia University, 1944), pp. 350-352.

⁵⁹ Dybvad, Vnderuissning, sig. D.

⁶⁰DBL, Vol. II (1933), pp. 548-549. Ivar Bertelsen may have been Tycho's teacher of rhetoric; see J. R. Christianson, "Tycho Brahe at the University of Copenhagen, 1559-1562," Isis, 1967, 58: 200.

⁶¹ Ivar Bertelsen, Formaning til en Christelig och alffuorlig Poenitentze (Copenhagen: Laurentz Benedicht, 1561). LN No. 395

⁶² Following the introduction to King Frederick II, Dybvad's first chapter treats what a pious Christian should learn from "this gruesome comet" and runs sig. [Aiiij^v]-C of Vnderuissning; the second chapter treats previous comets and runs sig. [C^v]-D; the third chapter contains Dybvad's analysis of the comet of 1577 and runs sig. D-[Diiij].

⁶³ Dybvad, Vnderuissning, sig. [Dij^v]-[Diiij].

⁶⁴Ibid., sig. [Diij^v]-[Diiij].

⁶⁵TBDOO, Vol. IV (1922), p. 5.

⁶⁶Ibid., Vol. VII, p. 47.

⁶⁷ The manuscript is now in the Royal Library (Det kongelige bibliotek), Copenhagen, Denmark, bound with other manuscripts of Tycho Brahe's cometary observations and catalogued as Gammel kongelig samling 1826, 4°. Fols. 32v, 33r, 33v, 34r, 35r, 35v, and 36r are omitted from the printed version of the manuscript, TBDOO. Vol. XIII (1926), pp. 289-304. In the manuscript, they follow the text with which TBDOO concludes page 304 (fol. 33^v and 34^r are blank). Victor E. Thoren's perceptive remarks were a great help to me in the interpretation of these sketches.

⁶⁸ Tycho summarizes this view in TBDOO, Vol. IV (1922), p. 382.

⁶⁹Ibid., Vol. IV, pp. 382-383. Tycho's relationship to Paracelsus was certainly not one of slavish dependence, but he did speak in laudatory terms of Paracelsus on various occasions, see, e.g., ibid., Vol. VI, p. 224, or Vol. VII, pp. 169-171. Karin Figala's analysis of Tycho's approach to alchemy revealed it to be thoroughly Paracelsian; see "Tycho Brahes Elixier," Veröffentlichungen des Forschungsinstituts des Deutschen Museums fur die Geschichte der Naturwissenschaften und der Technik, Reihe C. Quellentexte und Übersetzungen, 1972, 13: 139-176. See also Sten Lindroth, Paracelsismen i Sverige till 1600-talets mitt (Uppsala: Almqvist & Wiksell, 1943), pp. 68-69 et passim. J. L. E. Dreyer has pointed to the Paracelsian character of Tycho's famous "hieroglyphs' of astronomy and alchemy, bearing the legends "Svspiciendo Despicio" and "Despiciendo Svspicio," which he displayed over the portals of Uraniborg and on the title page and colophon of his published works; see TBDOO, Vol. I, p. xi, Vol. VI, pp. 144-146, Vol. V, pp. 3 and 162. In celestial matters, Paracelsus may have been the stimulus to Tycho's rejection of the Aristotelian sphere of fire below the moon, though Tycho remained ambivalent toward Paracelsus' transposition of that element into the celestial regions; see the lengthy discussion in his letter to Christopher Rothmann, some twelve years later (Feb. 21, 1589), in TBDOO, Vol. VI, pp. 166-181. Tycho also recognized that Paracelsian cosmology was consistent with the evidence of the new star of 1572 and the comet of 1577, whereas Aristotle's view was not. Pratensis was a Paracelsian, and Petrus Severinus was one of the most famous interpreters of Paracelsus in that generation; both were close to Tycho in the 1570s.

⁷⁰ For his dedications, see particularly LN Nos. 532, 544-546, and 552.

⁷¹ Rørdam, "Dybvad," pp. 109-110.

⁷² Besides Tycho's ties with Hesse-Cassel, Venice, and the court of Emperor Rudolf II, he later had many contacts with England and Scotland; see Ilsøe, "Gesandtskaber." Likewise, Tycho's Dutch connections at a later date were numerous, but the most significant fact at this time is that at least three of his four brothers had served in armor to defend the Dutch cause; two of them won their spurs of the Count of Schwarzburg-Rudolstadt, a brother-in-law of the Prince of Orange; and Steen Brahe was one of those who accompanied William the Silent on his first invasion of the Low Countries in 1568.

⁷³ Dybvad's mathematical, scientific, and theological theses, treatises, orations, and editions are listed in LN Nos. 479, 532-552, 678, and 987.

⁷⁴ Moesgaard, "How Copernicanism took Root," pp. 117-119.

⁷⁵ Dybvad, Vnderuissning, sig. [Biiij].

⁷⁶Ibid., sig. Bij.

⁷⁷ See n. 14 above. The manuscript of seventeen discourses from the Palace Academy of Henry III is now in the Royal Library in Copenhagen, according to Yates, French Academies, p. 107, n. 3, though she does not explain how it got there. I have not examined this manuscript.

⁷⁸ Frances A. Yates, The Rosicrucian Enlightenment (London/Boston: Routledge & Kegan Paul, 1972), pp. 34-35, discusses a purported meeting of princes at Lüneberg on July 17, 1586, including representatives of Navarre, Denmark, and England, with the object of forming a Protestant league of defense against the Catholic League in France. Yates notes that some scholars have associated this league or "Confederatio Militiae Evangelicae" with the origin of the Rosicrucian movement, and she states that this would be in accord with her own interpretation, but she pursues the particular matter no further. According to V. Mollerup, Danmarks riges historie, Vol. III, Part 2 (Copenhagen: Det nordiske forlag, 1906), p. 226, this meeting was called by King Frederick II. More central to Yates' interpretation is the role of Elizabeth, daughter of King James I of England and Anne of Denmark. Yates describes the "magical" atmosphere of Elizabeth's garden and castle in Heidelberg as "an outpost of Jacobean England, a citadel of advanced seventeenth century culture" (p. 14). Elizabeth was a granddaughter of King Frederick II of Denmark, and her mother, Anne of Denmark, maintained a rather brilliant court in England. H. D. Schepelern, Museum Wormianum (Odense: Wormianum, 1971), pp. 314-315, goes so far as to trace the aesthetic interests of Elizabeth's brother, King Charles I, to their mother, and he shows that similar interests were strong among the Danish descendants of King Frederick II, frequently merging with religious and arcane interests. Most striking in the present context of Rosicrucian influences is Schepelern's description, pp. 315-323 and English summary, pp. 382-383, of the tremendous labor of King Christian IV (Elizabeth's uncle) at Frederiksborg, where he tore down his father's great castle and rebuilt it as an immense Rosicrucian emblem in the very years when Elizabeth was living in Heidelberg.

⁷⁹ Peter J. French, John Dee. The World of an Elizabethan Magus (London: Routledge & Kegan Paul, 1972). Roger Howell, Sir Philip Sidney. The Shepherd Knight (Boston: Little, Brown, 1968). Yates, Astraea and Giordano Bruno. Thomas Keith, Religion and the Decline of Magic (New York: Scribner's, 1971), pp. 312-314, treats the role of astrology, but only in rather trivial matters and not in the realm of policy; his view of the clash between religion and astrology, pp. 358-370, reveals a picture in England which was quite different from that in Denmark.

⁸⁰ R. J. W. Evans, Rudolf II and His World. A Study in Intellectual History 1576-1612 (Oxford: Clarendon Press, 1973). For a clearer sketch of the role of Tycho at the imperial court, however, see Norlind, Tycho, pp. 265-266 and 300-320, German summary pp. 438-441.

⁸¹ Hellman, Comet of 1577.

⁸²TBDOO, Vol. IV, pp. 379-396.

⁸³ This is not apparent from TBDOO; see n. 57 above. None of Tycho's almanacs or annual prognostications are known to be extant. On P. J. Flemløse's Astrologia, which Tycho had him write in response to a request from King Frederick, see Christianson, "Astrologia," p. 213.

⁸⁴ Note that the diagram mentioned in the text on p. 386 is not found in either extant copy of the manuscript. If my argument is correct, it would have been in a royal presentation copy, now lost. For Dreyer's notes on this manuscript, see TBDOO, Vol. IV, pp. 511-512. See also Norlind, Tycho, pp. 127-129, and Hellman, Comet of 1577, pp. 122-136.

⁸⁵ Owen Gingerich, "The Astronomy and Cosmology of Copernicus," in G. Contopoulos and G. Contopoulos, eds., Highlights of Astronomy (Boston: Reidel, 1974), pp. 67-85. See also Owen Gingerich, "Copernicus and Tycho," Scientific American, Dec. 1973, 224 (6):86-11. These diagrams are in a copy of the first edition of Nicolaus Copernicus, De revolutionibus orbium coelestium (Nürnberg, 1543). Gingerich and Robert S. Westman have recently located two other first-edition copies of Copernicus containing annotations by Tycho. They are preparing a detailed analysis of the Tychonic materials in all three copies for future publication in Centaurus.

⁸⁶ Tycho specifically cites Copernicus, not Albumasur, whom Hartner saw as his inspiration; see Willy Hartner, "Tycho Brahe et Albumasar," La science au seizième siècle, pp. 135-150. See also Moesgaard, "Copernican Influence," and Wilhelm Norlind, "Tycho Brahes Världssystem. Hur det tillkom och utformades," Cassiopeia, 1944, 55-75. By a similar process, Maestlin's studies of the comet of 1577 made him a Copernican; see Robert S. Westman, "The Comet and the Cosmos: Kepler, Mästlin and the Copernican Hypothesis," in Dobrzycki, ed., Reception, pp. 7-30. Bruno's Hermetic Copemicanism, on the other hand, is quite another thing as described by Yates, Giordano Bruno, pp. 235-247 et passim.

⁸⁷ Die Österreichische Nationalbibliothek, MS Codex Vindobonensis 10.689³², "… HieZuischen hab ich durch meine obseruation den locum Cometæ gefunden Darumb achte ich das er sseij in Spera Veneris gestanden So man die gemeine Austeilung orbium Celestium nachfolgen Will. Wan Man aber Nach meinung etliche alien Philosopham Vnd Zu Vnssere Zeiten des Copernicj Vur gutt Anstehe das der ♀ Necht der Sonne vnd die Venus Rundtt vmb den Mercurio Circa Centrum Solis ire orbes haben quæ ratio non admodum absona est Veritatj etiamsi Sol prexet Copernicj habent Hypoteses non statuantur quessere in Centro Vniuersj. So Volgtt hie aus das diesser Comet sseij generiet Zuischen den Orbe ☾ vnd den Vorgenante Orbe Veneris Welchen Sie vmb die Sonne designirt…."

⁸⁸ Die Österreichische Nationalbibliothek, MS Codex Vindobonensis 10.689³³, previous to final rewriting.

⁸⁹ Die Österreichische Nationalbibliothek, MS Codex Vindobonensis 10.689³³, after rewriting. See TBDOO, Vol. IV, p. 388.

⁹⁰ Garrett Mattingly, The Armada (Boston: Houghton Mifflin, 1959), pp. 172-86. In his later, major works, Tycho used the word instauratio to describe what he was attempting to achieve in the field of astronomy. Cf. Charles Webster, The Great Instauration: Science, Medicine and Reform 1626-1660 (London: Duckworth, 1975), who argues that instauratio to 17th-century British puritans expressed a conviction that Christian civilization was approaching its final age, characterized by the revival of learning. Webster links his instauratio to the thought of Bacon, but much of it is similar to Tycho's thought in 1577; this emphasizes the urgency of investigating Bacon's connections with Tycho, which to my knowledge have never been studied in detail.

⁹¹ E.g., John Dee, Giordano Bruno, and Emperor Rudolf II; see Yates, Giordano Bruno, French, John Dee, and Evans, Rudolf.

⁹² A number of Scandinavian scholars have anticipated various aspects of this approach. Oskar Garstein, Cort Aslakssøn (Oslo: Lutherstiftelsen, 1953), pp. 51-67 et passim, investigated the relationship between science and religion in Tycho's thought. Velio Helk, Laurentius Nicolai Norvegus S.J. (Copenhagen: Gad, 1966), probing the Counter Reformation in Scandinavia, has touched upon Tycho and his circle in several surprising contexts, see esp. pp. 287-289 and 345. Kristian Peder Moesgaard has written on Tycho and the tradition of Copernicanism in Denmark, and William Norvin on Ramism. Oluf Friis summarized Tycho's influence upon a whole era of Danish intellectual life. Troels-Lund, "Peder Oxe," Historiske fortœllinger. Tider og tanker, 1911, 2: 327-329, and after him, Erik Arup, Danmarks historie, Vol. II (Copenhagen: Hagerup, 1932), pp. 620-622 and 645-647, pointed to the affiliation between Tycho and such political figures as Peter Oxe and Niels Kaas; cf. Svend Cedergreen Bech, Danmarks historie, Vol. VI (Copenhagen: Politiken, 1963), pp. 458-472 and 496-497. Harald Ilsøe has written a splendid article on the cultural dimensions of diplomacy in Tycho's day. Wilhelm Norlind devoted a lifetime to Tychonic research and besides his monumental biography of Tycho, wrote an article on the origin of the Tychonic system, "Tycho Brahes världs-system. Hur det tillkom och utformades," Cassiopeia, 1944, 55-75. H. D. Schepelern did much to illuminate the transition to a new generation of Danish scientists in the years following Tycho's demise.