Copernicus first circulated his ideas in 1514, but the Catholic Church did not get around to condemning his heliocentric cosmology until the Inquisition’s injunction against Galileo in 1616. If the Church opposed science and condemned any idea that was contrary to the Bible, why the century long delay? And why did they never persecute Copernicus himself? Many new atheists explain this by claiming he kept his ideas secret and only published his book when he was on his deathbed to escape the wrath of the Church. The reality is quite different.

The idea that Copernicus lived in fear of the Catholic Church and kept his heliocentric theory secret as a result has a long pedigree and its most prominent early proponent was the notorious nineteenth century polemicist, Andrew Dickson White. It was White’s 1896 opus A History of the Warfare of Science with Theology in Christendom that, with John William Draper’s History of the Conflict between Religion and Science (1874), established the Conflict Thesis or Draper-White Thesis, with its lurid narrative of religion perpetually struggling to prevent the advance of science. Despite the fact that twentieth century historians of science dismantled White and Draper’s claims and rejected the Conflict Thesis, it has permeated the popular perception of the history of science, due in no small part to it being peddled by prominent scientists such as Carl Sagan, Stephen Hawking and Neil deGrasse Tyson. As a result, this debunked idea is accepted without question by many new atheists, along with its supporting mythology which makes up White and Draper’s books. This includes White’s version of the story of Copernicus and the deathbed publication of his De revolutionibus orbium coelestium in 1543.

White calls Copernicus “a plain, simple-minded scholar” (though he means “straight forward” rather than “stupid”) who “first fairly uttered to the world the truth, now so commonplace, then so astounding, that the sun and planets do not revolve around the earth, but that the earth and planets revolve around the sun” (Warfare, p. 24). White informs his readers that Copernicus had “been a professor in Rome, but as this truth grew within him, he seemed to feel that at Rome he was no longer safe” (p. 25) He then depicts Copernicus keeping his radical theory secret out of fear and says “for more than thirty years it lay slumbering in the minds of Kopernik and the friends to whom he had privately intrusted [sic] it” (p. 25) Then, according to White, Copernicus decided to seek out a publisher for the book on this theory, “but he dare not send it to Rome, for there are rulers of the older Church ready to seize it”, nor could he send it to Wittenberg, “for there are leaders of Protestantism no less hostile”. So he says Copernicus “instrusted [sic] it to Osiander of Nuremberg” (p. 26).

But, alas, the publisher Osiander betrays Copernicus and, in “a groveling preface” presents it as a hypothesis only “not as a fact“. “Thus”, White laments,”was the greatest and most ennobling, perhaps, of scientific truths …. forced, in coming before the world, to sneak and crawl.” (pp. 26-7). Then comes the climax of this story, with Copernicus on his deathbed finally, on May 24th 1543, taking hold of the printed edition of his masterwork. “A few hours later, he was beyond the reach of those mistaken, conscientious men, whose consciences would have blotted his reputation, and perhaps have destroyed his life.” (p. 27) In White’s dramatic retelling, Copernicus had only managed to escape the censorship of the Church and the rack and the stake of the Inquisition through secrecy, subterfuge and delaying publication until his death.

Not surprisingly this vignette of secrecy and intrigue has been repeated many times since 1896 and has entered the folklore that makes up many people’s understanding of the history of science. In one of a number of historically confused comments on an earlier post on this blog, former fundamentalist Christian turned atheist author, Edward T. Babinski, repeated the deathbed publication story:

“Copernicus refused to published his manuscript on his heliocentric theory early on, but waited and waited, and would have waited till after he had died, but some brave Protestant urged him to get it published, which it was, just prior to Copernicus’s death. If the Church was so neutral and even pro-science, then why wait?”

In a 2014 blog post full of typical historical howlers, new atheist grumpy uncle PZ Myers sneered at a mention of Copernicus as a “Catholic astronomer”, snarling “[Copernicus] delayed publication out of fear; only saw his ideas in print on his deathbed [and his] book was prohibited by the Catholic Church in 1616”. And just a few weeks ago in an error-filled article rehearsing the hoary myth of Giordano Bruno as a martyr for reason, the atheist blogger Rick Snedeker also repeated the deathbed publication story:

“The great pioneering Polish astronomer Nicolaus Copernicus (1473-1543), who died five years before Bruno was born, had developed radical ideas about the nature of the cosmos (which ultimately proved largely correct). He released them publicly only on the eve of his death (he had long hesitated publishing his theory because he feared Church blowback, as it refuted scripture).” (Gadzooks: The Faith in Facts Blog, “Martyrs of Reason: Giordano Bruno“)

As with many of the myths that make up new atheist historiography, this one conforms to the Draper-White “conflict” narrative, has a noble rationalist hero and Christian villains, a moral and an ultimately happy ending. And, like them, it is a pseudo historical fairy tale.

Copernicus and his World

Copernicus was, unsurprisingly, a man of his time and, equally unsurprisingly, a devout Catholic all his life. Born into a relatively well off mercantile family on 19 February 1473, Copernicus was the youngest of four children. His father, also called Nicholas, was a copper merchant from Kraków who moved to Copernicus’ birth city of Thorn around 1458. His mother, Barbara Watzenrode, was the daughter of a wealthy merchant and city councillor in Thorn and her brother, Coperncius’ uncle Lucas Watzenrode the Younger, was to be a major influence on his young nephew’s career. In 1483 Copernicus’ father died and his uncle took over the upbringing and education of his nephews and nieces and probably sent the young Nicholas to St John’s School in Thorn, given that he had previously been a master there.

In 1489 Watzenrode was elected Prince-Bishop of Warmia and two years later his nephews Nicholas and Andrew both commenced study at their uncle’s alma mater, the University of Kraków. This university was already renowned as a centre of modern astronomical study and later traditions indicate that Copernicus was taken under the wing of Albert Brudzewski; professor of Aristotelian philosophy but also a respected mathematician and astronomer. In 1495 Copernicus left Kraków without completing his Arts degree to take up a post as canon under his uncle, the Bishop of Warmia. This was delayed, possibly by an appeal to Rome against the appointment, so Watzenrode sent both of his nephews to Italy to study canon law instead.

Copernicus studied at the University of Bologna from 1496 to early 1501, but he does not seem to have had great enthusiasm for canon law, as he also attended lectures on the humanities and astronomy. Renaissance Italy was the epicentre of humanist enthusiasm for Greek and Roman literature and Copernicus seems to have thrived in the atmosphere of Bologna, where he also became the assistant to and disciple of the astronomer, Domenico Maria Novara da Ferrara. He visited Rome for the Jubilee year of 1500, where he stayed for some months and seems to have delivered private lectures on astronomical calculation which were well-received. He returned to Warmia in 1501, but went back to Italy later that year, again at his uncle’s instigation, to study medicine at Padua and complete his doctorate in canon law, returning to his native Prussia for good in the autumn of 1503.

And for many proteges of powerful bishops, that would probably have been the extent of their scholarly career. In a period in which careers were shaped by more powerful patrons and relatives, many would have taken their new education and applied it as administrators and functionaries, leaving any further scholarly work as a pastime. Of course, in a way, that is what Copernicus did. For the next 30 years he worked as a canon of the bishopric of Warmia, serving in the retinue of his uncle and his successors, acting as their physician, undertaking administrative duties and occasional diplomatic missions, managing economic matters, making maps and doing everything from settling land disputes to organising provisions in preparation for a siege by an invading army of the Teutonic Knights. He took minor orders and may or may not have ever been fully ordained as a priest. He had no children, though he did have a relationship with his housekeeper Anna Schilling, causing a minor scandal that resulted in her banishment from his new home town of Frombork in 1539. He was known to continue his interest in astronomy and a 1530s satirical play by Wilhelm Gnapheus depicts him as an aloof astrologer who was alleged to have a neglected unpublished work tucked away in a chest.

But Copernicus stayed engaged with the astronomical studies of the time and was well connected to the humanism he had encountered in his time in Italy. His friends, supporters and correspondents were all humanists who were great admirers of Erasmus of Rotterdam: men like Tiedemann Giese, Alexander Scultetus, Feliks Reich and Achacy Trenck, who like Copernicus were clergy and functionaries in Prussia and the Kingdom of Poland. Copernicus certainly saw himself as a humanist man of letters, and translated and published a collection of Greek poems by the seventh century Byzantine poet Theophylact Simocatta. But he also saw himself primarily as a mathematician in a period where astronomy was a branch of mathematics. He was of a generation that was building on the new mathematical astronomy done by Georg von Peuerbach and his disciple Johannes Müller von Königsberg, better known as Regiomontanus. While both had done much to refine Ptolemaic astronomy, by the time Copernicus left Italy there was growing dissatisfaction among pure mathematical astronomers like Copernicus with the accuracy of the model that had dominated western astronomy since the second century AD.

This is because what we call “the Ptolemaic model” was actually a synthesis between the physics of Aristotle and the mathematical astronomy detailed in Ptolemy’s Syntaxis Mathematica, known in the Middle Ages as the Almagest. In effect, Ptolemy’s model was an attempt to reconcile accepted Aristotelian physics with what can be observed in the sky. The result was something of a mathematical kludge: with awkward combinations of epicycles, equants and deferents all designed to maintain the geocentric system of spheres and circular orbits required by Aristotle’s physics, while still allowing astronomers to make observations that were reasonably accurate. By the early fifteenth century, mathematical heirs to Peuerbach and Regiomontanus were becoming more acutely aware of just how much the Ptolemaic system was ramshackle from both a physical and a mathematical point of view. As more accurate observations were made, some of them – such as the lunar occultation of the star Aldebaraan observed by Copernicus and his astronomical mentor Domenico Maria Novara in March 1497 – led to doubts about the accuracy and therefore the ongoing utility of Ptolemy’s model.

Copernicus needs to be understood in this context: he saw his heliocentric model as a resolution, bringing the two ways of seeing the cosmos together; an answer to these theoretical tensions which preserved the purity of the (assumed) circular orbits of the planets, by getting rid of the (to him) most inelegant part of Ptolemy’s system – the equant – while also trying to make his system more mathematically precise. [For those who need a primer on the Ptolemaic System and how Copernicus’ alternative reworked it, Wikipedia has a fairly good summary]. So, contrary to the conception of Copernicus as the great observational astronomer who completely tossed out the medieval artificiality of the Ptolemaic model and replaced it with solid science, Copernicus was actually, in large part, trying to make the mathematics fit closer to the semi-mystical Greek ideal of concentric celestial spheres and circular orbits.

The earliest mention of Copernicus’ theory – Matthew of Miechów’s 1514 catalogue

The Reception of the Theory: Pre-1543

Which brings us back to the story of Copernicus’ fear of the Church, the secrecy around his theory and the deathbed publication of De revolutionibus. Copernicus was working within a new tradition of mathematical analysis of and commentary on the Ptolemaic model where there had been, as noted, an increasing dissatisfaction with the model’s accuracy and usefulness. Given that it had been the accepted model for well over one thousand years and was based on accepted physical principles that dated to more than 300 years before that, the intellectual inertia against more than minor adjustments to it was substantial, but there was an increasing need for astronomy to be accurate: the growing awareness that the Julian Calendar was in urgent need of reform being one reason for this.

Even the physics that underpinned the model was already open to question. Back in the mid fourteenth century Nicolas Oresme had analysed the evidence for and against the idea of a daily rotation of the earth in his Livre du ciel et du monde and concluded that it was actually entirely possible, though he ultimately retained the Aristotelian belief that it remained stationary, largely because he could not make a rotating earth fit with a larger cosmographical model that made sense. And the fact that everyone understood that the Ptolemaic model was essentially a mathematical calculating device rather than a map of what was physically happening in the heavens meant that, at least in theory, they understood that it could be replaced by something better. No less a figure than Thomas Aquinas made this point several times. For example:

“The suppositions that these astronomers have invented need not necessarily be true; for perhaps the phenomena of the stars are explicable on some other plan not yet discovered by men” (De coelo, II.17)

Or again:

“The theory of eccentrics and epicycles is considered as established because thereby the sensible appearances of the heavenly movements can be explained; not, however, as if this proof were sufficient, forasmuch as some other theory might explain them.” (Summa theologica, I, q.32, a.1, ad. 2)

Speculation about the motion of the earth continued, with Nicholas of Cusa including the idea in his conception of an infinite and unbounded universe in his De docta ignorantis (1440). Around 1518 Celio Calcagnini of Ferrara wrote an essay entitled Quod Coelum stet, Terra autem moveatur (That the Heaven Stands Still whereas the Earth Moves) which was published in Basel in 1544. None of these writers were condemned by any Christian church.

Copernicus was not even the first person to publish an alternative to the Ptolemaic model. In 1538, five years before the publication of De revolutionibus, Giralamo Fracastoro published Homocentrica, which detailed a complex system that did away with Ptolemy’s epicycles and eccentrics and replaced them with a model based on concentric spheres. Like Copernicus, Fracastoro dedicated his book to Pope Paul III. And like Copernicus, he was inspired by the awkwardness and imprecision of the Ptolemaic model to look back to pre-Ptolemaic alternatives for inspiration – in Fracastoro’s case he looked to the system attributed to Plato’s pupil Eudoxos. But unlike Copernicus’ model, that of Fracastoro was vastly more complicated than the one it sought to replace and even more removed from likely physical actuality. Fracastoro’s system required no less than 77 concentric spheres to function but it did not have the accompanying computational methods that made Ptolemy’s system so useful. He did not have the patience or the mathematical skill that allowed Copernicus to not only replace the more awkward elements of Ptolemy, but match his computational utility.

So there was no dogmatic imperative or doctrinal barrier against someone coming up with a better theory and others were already toying with other models. On the whole, however, the hold that Aristotelian physics had on natural philosophy was difficult to escape due to a lack of comprehensive viable alternatives that accounted for as much as Aristotle’s systems did. The fact that several interpretations of Biblical verses conformed with Aristotle in the Scholastic synthesis made this inertia against overturning the Ptolemaic model even greater.

But Copernicus, driven by his increasing dissatisfaction with the mathematical accuracy of Ptolemy’s system, decided to overturn it anyway. He is likely to have begun this project as early as the time of his studies in Italy or soon after his return to Prussia in 1503 and he seems to have had completed his manuscript, minus some later adjustments and additions, by around 1532. So was this, as White claimed in his Warfare of Science with Theology, a period in which Copernicus fled from Rome because “he was no longer safe” and then kept his ideas hidden, shared only with a few trusted friends, until he thwarted the Catholic Church by keeping his book’s publication until he was about to die? In a word: no.

To begin with Copernicus definitely did not keep his ideas secret at all. He not only discussed them widely with his continent-wide circle of friends and compatriots, but around 1512 he also wrote an eight chapter summary of his theory – the so-called Commentariolus – which then circulated in unpublished form among interested astronomers and mathematicians. He seems to have sent a copy to the Cracow cartographer and historian Bernard Wapowski and it is this copy that probably found its way into the library of Matthew of Miechów, where its appearance in that library’s catalogue in 1514 is the first recorded mention of Copernicus’ theory. Copernicus’ friend and supporter, Bishop Tiedemann Giese of Culm, was almost certainly one of those who circulated the Commentariolus and he seems to have either sent a copy or at least written about the theory to the great Humanist scholar, Erasmus of Rotterdam – though another mathematician in Cracow, Johannes Broscius, later described Erasmus’ reception of the thesis as “temperate”.

Audiences in Rome, on the other hand, were rather more enthusiastic. In 1533 the German scholar and theologian Johann Albrecht Widmanstadt (or Widmannstetter) was serving as a secretary to Pope Clement VII and was invited by the pope to give a lecture on Copernicus’ theory. Widmanstadt gave at least one lecture (or it may have been a series) in the Vatican gardens for the pope and leading members of the Curia and Papal court, including Cardinal Franciotto Orsini, Cardinal Giovanni Salviati, the Bishop of Viterbo Giampietro Grassi and the papal physician Matteo Corte. The pope was fascinated by the theory and rewarded Widmanstadt, who was a famous orientalist and Grecophile, with a precious manuscript of Alexander of Aphrodisias’s De sensu et sensibili, with Widmanstadt proudly inscribing the circumstances in which he received this gift in its front pages.

Widmanstadt continued as papal secretary to Clement’s successor, Pope Paul III, and then to Cardinal Nikolaus von Schönberg after 1535. It was probably from Widmanstadt that von Schönberg learned of Copernicus’ theory, leading him to write to Copernicus to encourage him to publish his book:

“Some years ago word reached me concerning your proficiency, of which everybody constantly spoke. At that time I began to have a very high regard for you, and also to congratulate our contemporaries among whom you enjoyed such great prestige. For I had learned that you had not merely mastered the discoveries of the ancient astronomers uncommonly well but had also formulated a new cosmology. In it you maintain that the earth moves; that the sun occupies the lowest, and thus the central, place in the universe; that the eighth heaven remain perpetually motionless and fixed; and that, together with the elements included in its sphere, the moon, situated between the heavens of Mars and Venus, revolves around the sun in the period of a year. I have also learned that you have written an exposition of this whole system of astronomy, and have computed the planetary motions and set them down in tables, to the greatest admiration of all. Therefore with the utmost earnestness I entreat you, most learned sir, unless I inconvenience you, to communicate this discovery of yours to scholars, and at the earliest possible moment to send me your writings on the sphere of the universe together with the tables and whatever else you have that is relevant to this subject. Moreover, I have instructed Theodoric of Reden to have everything copied in your quarters at my expense and dispatched to me. If you gratify my desire in this matter, you will see that you are dealing with a man who is zealous for your reputation and eager to do justice to so fine a talent. Farewell.” (Rome, November 1, 1536)

So it could not be more clear that the idea that Copernicus was fearful of religious persecution is pure fantasy. There is no evidence to support White’s claim that he somehow fled Rome in 1503 and he quite obviously did not keep his theory in any way “secret” – it was known to a network of scholars across Europe and, through them and his summary in the Commentariolus, to a wider group of interested intellectuals. The idea that it was fear of churchmen that inspired this mythical “secrecy” is also patent nonsense, given that both Catholic and Protestant scholars were aware of his theory well before 1543 and those who expressed great interest and admiration included several bishops, three cardinals and the Pope himself.

Copernicus’ Hesitation

Yet for several years after the encouragement of various supporters and the enthusiastic support of Cardinal von Schönberg, Copernicus still hesitated. If it was not fear of religious persecution that made him reluctant to publish, what was the actual reason? Writing later, in his prefatory dedication of De revolutionibus to Pope Paul III, Copernicus himself gives us an insight into the real source of his hesitation:

“Those who know that the consensus of many centuries has sanctioned the conception that the earth remains at rest in the middle of the heaven as its center would, I reflected, regard it as an insane pronouncement if I made the opposite assertion that the earth moves. Therefore I debated with myself for a long time whether to publish the volume which I wrote to prove the earth’s motion or rather to follow the example of the Pythagoreans and certain others, who used to transmit philosophy’s secrets only to kinsmen and friends, not in writing but by word of mouth …”

This is, in effect, more or less what he did from 1503 to 1543, though his Commentariolus meant the transmission was not entirely by word of mouth. This kind of private circulation of ideas was common in the period, because it kept the work in question within the confines of technical specialists. Publishing them, on the other hand, laid them open to analysis and criticism by all and, in an age of polymaths and overlapping intellectual disciplines, Copernicus knew this meant a wider, potentially more critical audience who did not share the his intellectual circle’s attitudes toward purist mathematical astronomy. So Copernicus’ dedication continues:

“[The ancient Pythagoreans] wanted the very beautiful thoughts attained by great men of deep devotion not to be ridiculed by those who are reluctant to exert themselves vigorously in any literary pursuit unless it is lucrative; or if they are stimulated to the non acquisitive study of philosophy by the exhortation and example of others, yet because of their dullness of mind they play the same part among philosophers as drones among bees. When I weighed these considerations, the scorn which I had reason to fear on account of the novelty and unconventionality of my opinion almost induced me to abandon completely the work which I had undertaken.”

Of course, Copernicus’ rhetoric here is working to blunt any criticisms his book would attract by casting the potential critics as “drones among bees”, but he is making it clear that it is the critiques by these other scholars that made him hesitate, not the purely theological objections of churchmen or any persecution by the Church hierarchy. He was obviously confident enough in his theory for it to be discussed by other fellow mathematici, but in a time when any scholastic, astrologer, mystic or even semi-educated crackpot saw themselves capable of judging astronomical works, he was not convinced wider dissemination of his theory was in his best interest. As he put is bluntly in his dedication to the Pope, “astronomy is written for astronomers”.

There is a further but related likely reason for his hesitation which he does not articulate but which needs to be remembered. While Copernicus and his followers and supporters certainly seem to have been convinced by his theory, they also knew that there were sound scientific objections to it, particularly on the grounds of physics. Copernicus knew what these objections were going to be and tried to head them off in his work, with fairly limited success. These problems were to become front and centre in the debate about the competing cosmological models that really began in the later sixteenth century and raged until they were finally settled by a combination of Kepler’s Laws and Newton’s new physics a century later. Copernicus and his followers did not acknowledge this at the time, but they would have known that at least some of the scientific objections they knew the theory would attract would be entirely valid and, at that stage, were actually impossible to refute fully.

But despite all these reasons for hesitation, Copernicus was convinced to change his mind and publish after all largely thanks to the efforts of Georg Joachim Rheticus. Rheticus was a Protestant who had been appointed as Professor of Mathematics at the new university of Wittenberg in 1536 by the Lutheran reformer, theologian and educator Philipp Melanchthon. Two years later he was given leave to go study with leading astronomers to expand his knowledge and while on this tour of Europe Rheticus heard of Copernicus and sought him out in Fromborg. Rheticus spent two years with Copernicus and became his most enthusiastic disciple, encouraging the ageing master to finally publish the full exposition of his model. In 1540 Rheticus published his Narratio Prima or “First Report” – an anonymous abstract of Copernicus’ De revolutionibus that laid out the heliocentric model in more detail than the Commentariolus. The Narratio was published first in Danzig and then in a second edition in Basel in 1541, with both editions attracting great interest. Copernicus was encouraged by the positive reception that the Narratio received and so finally decided to publish his full work, complete with its explanation of his initial reluctance.

By this stage Rheticus had returned to Wittenberg, so Coperniucus – now too old to travel – gave the manuscript of De revolutionibus to his friend Bishop Giese to deliver to Rheticus to oversee publication. Rheticus took the manuscript to the great German publishing centre of Nürnberg, but soon afterwards was asked by Melanchthon to take up a professorship of mathematics in Leipzig, so he entrusted the publication project to a fellow Protestant scholar, Andreas Osiander, though he stayed in contact with the project via an ongoing correspondence with both Copernicus and Osiander. These letters give a further insight into Copernicus’ lingering concerns about how his work would be received.

It seems the three continued to discuss the best way to present Copernicus’ work and that it was the novelty of the theory and the continuing influence of Aristotle on the cosmology of the day that concerned Copernicus. He seems to have feared, probably with good reason, that many non-specialists would dismiss his book without bothering to (or being capable of) working their way through its complex mathematics. As already noted, Aristotle had been the dominant influence on the view of the cosmos thanks to the way Ptolemy mathematically synthesised his physics and cosmology with what can be observed in the sky. Then both this and Aristotle’s philosophy generally had been further synthesised with Christian theology and Scriptural interpretation to form the Scholastic system that had dominated European thinking since the thirteenth century. By Copernicus’ time the Humanist movement had been pushing against the “Peripatetics” – more conservative thinkers who clung to the heavily Aristotelian-Christian system – but in physics and cosmology the “Peripatetics” definitely held sway; in no small part because the synthesis of Aristotle and Christian theology had proved so comprehensive and seemed so solidly-based. In letters to both Copernicus and Rheticus, Osiander suggested a strategy to get around the objections of the Aristotelians:

“The Peripatetics and Theologians will easily be placated if they hear that there can be different hypotheses for the same apparent motion and that these (of Copernicus) are not presented because they are certain but rather because they permit the most convenient way to calculate the apparent and compounded motions; and, it is possible that someone else may contrive other hypotheses so that to explain the same apparent motion one person may present suitable mental images (imagines), another even more suitable; and, each one is free – even better: each should be thanked – if he contrives even more convenient hypotheses.” (Wittenberg, April 20, 1541)

This was effectively the approach taken by Osiander in the infamous “Preface” that he attached to the final published version of De revolutionibus, suggesting that it could be read merely as a hypothesis and calculating device rather than physical theory (more on this below). But the point to note here is the term “peripatetics and theologians”, which is used twice in this letter to refer to the potential critics of the book. Clearly the issue was not simply “theologians” per se, but those theologians and philosophers who were especially devoted to Aristotle. It was not reaction to any contradiction of the Bible that concerned Copernicus and his editors, but rather the expected reaction to the contradiction of the synthesis between Aristotelian natural philosophy and theology that was the issue.

Early Reactions to ‘De revolutionibus’

If the genuine concern of Copernicus had been purely theologically-based rejection and furious Church condemnation, as the myth supposes, then surely this is precisely what we would have seen once the book was finally released in 1543. Certainly, given that Copernicus was dead by the time his book came to be read, he himself would only have suffered post mortem repudiation by a furiously anti-science Church, but surely if it was this expected religious response that stayed his hand for so many decades the reaction of the Church would have been all the more ferocious because he had escaped the Inquisition by his death. Except the reaction to the publication of De revolutionibus was … not much. Like the Narratio, it was well received by the specialists who had an interest in astronomy and cosmology, but there was no firestorm of condemnation or calls for the book to be declared heretical.

It is sometimes claimed that this was because the “Preface” inserted by Osiander mentioned above managed to convince everyone that the book was merely setting out a calculating method and was not meant to be taken literally, thus completely deflecting the religious condemnation it would otherwise have received. This argument makes little sense, however. Osiander’s preface certainly did set out to blunt ill-informed criticism of the work, as a later section of the letter to Rheticus and Copernicus quoted above makes clear. Osiander goes on to argue that highlighting the fact that all mathematical cosmological models were essentially just calculating devices would give room for “the Peripatetics” to consider Copernicus’ thesis carefully rather than rejecting it out of hand:

“In this manner, induced to leave behind their severe critique in order to pass over to the pleasures of investigation, first they will become more reasonable; then, after they have sought in vain, they will come over to the author’s opinion.”

So Osiander’s noting the fact that Coperncius’ model, like all such models, was first and foremost a mathematical device which agreed with the celestial phenomena was simply in keeping with the understanding of such models at the time. More importantly, however, it was not a ruse to convince everyone that the book should only be read this way, because anyone who read past the “Preface” could see fairly quickly that Copernicus clearly was arguing for the physical reality of his system. The Prefatory note was simply a way to overcome uninformed criticism and get potential a priori critics to consider the mathematical core of the book seriously.

It did not become completely clear that the “Preface” was an editorial addition and not by Copernicus himself until the second half of the seventeenth century, but analysis of the early reactions to the book make it clear that readers did indeed understand the model was meant to be taken as a literal, physical one and not just a calculation device and at least one, Giovanni Maria Tolosani (see below) worked out that the “Preface” was not written by Copernicus. Despite this, the religious reaction was minimal. It is often noted that no less a religious authority than Martin Luther rejected Copernicus on purely religious grounds, but the evidence for this is thin and actually not entirely certain. Luther’s comment is found in the collection of his “table talk” – a compilation of anecdotes and reported comments and sayings taken from notes made by students between 1531 and 1544 and then published as the Tischreden in 1566. Luther is reported to have referred dismissively to Copernicus:

“There was mention of a certain astrologer who wanted to prove that the earth moves and not the sky, the sun, and the moon. This would be as if somebody were riding on a cart or in a ship and imagined that he was standing still while the earth and the trees were moving. [Luther remarked] ‘So it goes now. 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’ [Joshua 10:12].”

This seems at first glance to be an open an shut case of a purely religiously-based rejection of Copernicanism by no less an authority than the father of Protestantism. But closer inspection shows that it is not quite this simple. The anecdote is recorded by Anthony Lauterbach and dated to 1539. Of course, this puts it four years before De revolutionibus was published and even two years before the first edition of the Narratio. Since we have good reason to believe that the Commentariolus was not in circulation in Wittenberg at this time, this comment is – at best – based on hearsay about Copernicus’ theory, not any considered objection to the (as yet unpublished) theory. It is also, by Luther’s usual standards, a very mild and off-handed dismissal, given that when the great reformer really wanted to make his disapproval known – about, for example, dirty revolting peasants or “lying Jews” – he was more than capable of issuing hundreds of pages of thundering condemnation. Then there is the problem that the “astrologer” in question is not named. So Luther could be referring to some second hand report about Copernicus, but given that the theory this person is supposed to have proposed is not heliocentrism but a revolving earth, it could also be a reference to Nicole Oresme, Jean Buridan, Nicholas of Cusa or any other pre-Copernican who had discussed the movement of the earth.

Rather more clear and certainly more significant is the reaction of Phillip Melanchthon, given that he was (unlike Luther) an actual philosopher literate in astronomy and the founder of the Lutheran education system. He was the patron of both Rheticus and Osiander but it seems he took a dim view of Copernicus’ theory. In a textbook he wrote published in 1549 he wrote:

“But some dare say, either because of the love of novelties or in order to appear ingenious, that the earth moves, and contend that neither the eight sphere nor the sun moves while they assign other movement to the celestial spheres and place the earth among the stars. The joke is not new. There is a book by Archimedes called ‘De Numeratione Arenae’, in which he reports that Aristarchus of Samos defended this paradox, that the sun remains fixed and the earth turns around the sun. And although clever workers investigate many questions to give expression to their ingenuity, the young should know that it is not good to defend such absurd opinions publicly, nor is it honest or a good example.” (Initia Doctrinae Physicae)

This seems a fairly clear rejection of Copernicus, though it does not make clear whether Melanchthon considered his theory “absurd” for scientific reasons, religious ones or both. It also needs to be considered that while this book was published in 1549, it had been written in 1545 soon after he had read De revolutionibus. Subsequent editions of Melanchthon’s book toned down the ridicule in this passage while retaining the rejection of the model as a physical actuality. Despite this, Melanchthon still encouraged the use of Copernicus’ model as a calculating device at Wittenberg University and other Lutheran institutions – an instrumentalist approach that has been dubbed “the Wittenberg interpretation” as a result.

For an objection to Copernicanism that has any clear substantial religious component we have to turn to Giovanni Maria Tolosani (c. 1470 – 1549), who was a Dominican friar from Florence, an adviser to the papacy and a skilled astronomer. Tolosani wrote a large work called On the Truth of Sacred Scripture which he completed around 1544. He then addended to it a series of 12 supplements on various topics, including one on Copernicus. Tolosani was very much an Aristotelian in the tradition of Thomas Aquinas and so exactly the kind of “Peripatetic” Copernicus suspected would reject his theory. And reject it he did – for exactly the combination of scientific and theological reasons we would expect from a Thomist:

“For by a foolish effort [Copernicus] tried to revive the weak Pythagorean opinion, long ago deservedly destroyed, since it is expressly contrary to human reason and also opposes holy writ. From this situation, there could easily arise disagreements between Catholic expositors of holy scripture and those who might wish to adhere obstinately to this false opinion.”

The dual reasons for rejection given here – that the theory is “contrary to reason and [it] also opposes holy writ” – were to form the basis for the rejection of Galileo 90 years later and, as an astronomer, Tolosani’s objections were based on both his upholding of traditional interpretations of relevant Biblical texts and his knowledge of Aristotelian physics. He argues that astronomy, as a mathematical discipline, has to be subordinate to the higher and “nobler” disciplines of physics and theology – “the lower science receives principles approved by the superior” – and he rejects Copernicus because his theory is contradicted on key points by both physics and theology and because he finds him “very deficient in the sciences of physics and logic”.

So this is no mere preacher rejecting Copernicus purely because he contradicts the Bible: its the synthesis of natural philosophy and theology and the weight of the tradition supporting that synthesis that Tolosani feels cannot be overturned by a mere mathematicus, practising a “lower” discipline and not dealing sufficiently with the physical problems with his theory. Interestingly, Tolosani also notes that “Master of the Sacred and Apostolic Palace [scholastic scholar Bartelomeo Spina] had planned to condemn this book, but, being prevented first by illness and then by death, he could not fulfil this intention”. So here is the reaction by “the Peripatetics” that Copernicus expected. But what is notable about it is how muted it is. Obviously we cannot know how much of an impact a refutation by Spina may have had, but Tolosani’s work had very little. His pamphlet was never published and vanished into the archives of his order in manuscript form only. There is some evidence that it was read by some of his fellow Florentine Dominicans and may have influenced Tommaso Caccini, the Dominican preacher whose sermon attacking Galileo on December 20, 1614 began the whole Galileo Affair. Apart from this unpublished pamphlet, however, there is little sign of any criticism of De revolutionibus that had any substantial religious basis.

“The Book Nobody Read”

For most of the rest of the period from 1543 to around 1600 the reaction to De revolutionibus was twofold. On one hand, the overwhelming majority of astronomers did not accept Copernicus’ model as a physical system, largely because of the scientific objections to it based on Aristotle’s physics. On the other hand, its mathematical sophistication was appreciated and while it was no more precise than Ptolemy’s model, it was easier to use for some calculations. In 1551 Erasmus Reinhold used Copernicus’ calculations as the basis for his Prutenic Tables – a new set of ephemerides intended to replace the earlier Alphonsine Tables that astronomers, astrologers and navigators had been using for the previous 300 years. These planetary tables were highly practical instruments that laid out the weekly, daily and hourly positions of the various heavenly bodies, but the inaccuracy of the old Alphonsine Tables had long been recognised and it was hoped that Reinhold’s new tables would be better. As it turned out, this was not really the case: some aspects the new tables were better than their predecessors, others about the same and in some respects they were worse. Despite this, the Prutenic Tables came to be widely adopted and eventually formed the basis of the calendar reform of Pope Gregory XIII in 1582, with the establishment of the Gregorian Calendar still used to this day.

The use of the Prutenic Tables probably raised the profile of Copernicus’ theory, but it did not greatly increase the acceptance of his model as anything other than a mathematical calculating device. Reinhold himself rejected the Copernican theory on physical grounds and translated Copernicus’ calculations back into a geocentric model and the fact that the new Tables were not significantly more accurate probably also stunted the wholesale acceptance of the theory. On the whole , the scientific reaction to De revolutionibus was that it was great mathematics, but bad physics. Writing in 1578, Pierre de la Ramée of the Collège Royal in Paris appreciated the Prutenic Tables but was not convinced about Copernicus’ “vain and cumbersome” theory:

“If only Copernicus had addressed the edification of astronomy without hypotheses! In fact, it would have been much easier for him to trace an astronomy in accordance with the truth of heavenly bodies than [to make] such a gigantic effort to move the Earth, forcing us to look at and speculate on the immovable stars from a moving Earth.” (Scholae mathematicae, II.47)

In 1559 Thomas Hill published The School of Skill in which he lays out the accepted scientific objections to Copernicus’ model in detail and then makes reference to objections based on Scripture rather briefly, as something of an afterthought. For scholars before around 1600 the issues with Copernicanism were primarily scientific, not religious. Harvard historian of science Owen Gingerich undertook an 30 year long analysis of the surviving copies of the first two editions of De revolutionibus – 601 copies in all – and discovered something interesting. In The Book Nobody Read: Chasing the Revolutions of Nicolaus Copernicus (2004) Gingerich analyses the handwritten notes and marginal comments in the editions he had examined and found that while the mathematical sections of the book were usually heavily annotated, the sections where he defends his theory as a physical reality were generally not. This pattern seems to reflect the consensus of the time – that it was useful mathematically but unconvincing as a physical model. (Perhaps The Book that Was Inconsistently Annotated would have been a more accurate title, though it would have been hard to get a publisher to agree to that one).

And this also fits with the evidence on how few scholars actually accepted Copernicus’ theory prior to the Galileo Affair. Robert S. Westman’s survey of writings from 1514 to 1600 turns up just 11 writers who accepted Copernicanism as something other than a calculating device in this period: Thomas Digges and Thomas Hariot in England; Giordano Bruno and Galileo Galilei in Italy; Diego de Zuñiga in Spain; Simon Stevin in the Low Countries; and Georg Joachim Rheticus, Michael Maestlin, Christoph Rothmann, and Johannes Kepler in Germany, though it seems Rothmann later changed his mind (see Robert S. Westman, “The Astronomer’s Role in the Sixteenth Century: A Preliminary Study,” History of Science, 18 (1980): 105-147, p. 106). Pietro Daniel Omodeo’s survey of Copernicus’ reception in Copernicus in the Cultural Debates of the Renaissance: Reception, Legacy, Transformation (2014) arrives at much the same conclusion, though he would argue the English scholar John Feild could possibly be added to the total. If we take the date right up to 1616, the eve of Galileo’s first encounter with the Roman Inquisition, we can also add William Lower and Paolo Foscarini. This means that when the Inquisition came to the conclusion that Copernicanism was “absurd in philosophy”, it had the overwhelming majority of European astronomers and physicists on its side. In other words, the Church backed the scientific consensus – contrary to the myth that the Galileo Affair was purely a case of “religion versus science”. Christopher Graney’s superb Setting Aside All Authority: Giovanni Battista Riccioli and the Science against Copernicus in the Age of Galileo(2015) shows just how strong the scientific case was against heliocentrism even a generation after Galileo and why the consensus of science did not change until well after Newton’s Principia Mathematica (1687). Despite this, many still strenuously resist the fact that the Church’s opposition to Galileo and heliocentrism was primarily based on this clear scientific consensus.

Of course, myths die hard, especially when they are bolstered by a combination of ignorance and prejudice. The myth that Copernicus feared religious persecution and delayed publication of his book as a result is nonsense. He was part of a late medieval/early modern culture that was already questioning the Ptolemaic and Aristotelian orthodoxy and looking for a more elegant and precise mathematical underpinning for astronomy. He did not keep his theories secret and was strongly encouraged and supported in his work by leading churchmen, including several bishops, three cardinals and the Pope. His hesitation came from his correct perception that Aristotelian scholastics would reject his thesis primarily on physical grounds, though their synthesis of that physics with theology would also be a motivator. Finally, when he did publish his work the religious objections were few and far outweighed by scientific ones until the discoveries of the seventeenth century slowly turned the consensus in the favour of heliocentrism.