Gemusaeus’ reaction, although serving as advertising for his friend Oporinus, is interesting for several reasons. He acknowledges immediately that the Fabrica marks a break with the past, although he interprets it, in line with Vesalius’ own rhetoric, as a correction, interpretation, and proper restoration of Galen’s anatomical enterprise. Gemusaeus was a committed Galenist; he had after all been one of the editors of the major 1538 Basle edition of the collected works of Galen in Greek. His comment occurs in a preface to a work almost entirely dependent on Galen’s ideas and even wording. Nonetheless, he welcomes the Fabrica warmly as developing Galen’s anatomical ideas as well as bringing to light Galenic passages that had been previously unknown. His comments, and in particular his classification of Vesalius as a progressive Galenist, can be found elsewhere in sixteenth-century authors whose outlook, especially in therapeutics, remains firmly wedded to Galen. They appreciated that Vesalius had innovated, yet at the same time they could easily accommodate his discoveries within their overall framework. Far from overthrowing Galenism, the Fabrica in their eyes supported the general truths of Galenic medicine.
That the Fabrica could be seen in this way was one of the reasons for its dissemination, both swift and wide, among the medical professors of Europe, and for its general acceptance. Oporinus sent at the end of July 1543 a copy of the Epitome of the Fabrica to his friend Vadianus in St. Gallen, but the messenger fell into a river and the book was allegedly swept away; more likely, thought Oporinus, the man had decided to keep it for himself, preferring to have a damp copy than to send it back. A second copy was then sent to Vadianus by Oporinus, confident that this humanist would be only too delighted by the illustrations. By the end of 1543 all the copies of both Fabrica and Epitome with the booksellers in Leipzig had been sold, and a prospective buyer, the humanist and editor of Galen, George Agricola, had to place his order several days’ journey away in Frankfurt. By 1546 there were at least three copies in circulation in distant Oxford. Philip Melanchthon, the great Lutheran reformer and leader of the University of Wittenberg, read and annotated his copy, now in the National Library of Medicine, Bethesda, Md., from cover almost to cover. He was so delighted that he wrote on the flyleaf of the book a Latin poem praising its and its author's merits. He set to work to incorporate its findings in a revision of his treatise On the soul, published in 1551, that became standard reading in Lutheran schools and universities. Just as he felt it necessary that every good Lutheran should understand the truth about the soul, so he was concerned that they should have the best and most up-to-date information about the body that would, at the Resurrection Day, rise with the soul to heaven.
The same year, the German botanist Leonhard Fuchs, professor of medicine at Tübingen, published the first part of his Epitome of the fabric of the human body taken from Galen and Vesalius. This was avowedly a student text, based to an great extent on Vesalius, who was, in Fuchs’ opinion, divinely inspired to bring to light and make known a part of medicine almost extinct or besmirched with error. Fuchs distances himself from the ultra-Galenists, who sought to defend Galen at every turn, condemning their insolence and ignorance, but at the same time seeking to imply that he had been preaching the same message as Vesalius for many years.
Another early commentator, although somewhat more grudging, was the elderly Venetian doctor and anatomist Niccolò Massa (1485–1569). In 1536 he had published an Introduction to anatomy, claiming to have included in it the results of very many dissections and autopsies, and acknowledging that Galen had made many errors through relying overmuch on animals. But for all its claims to have seen everything that was described, the Introduction, although effective enough as a student guide to be reprinted as late as 1559, still followed Galen and Mondino extremely closely. Massa’s “book review” took the form of two letters, dated 20 and 23 January, 1544. He accepted almost all that Vesalius had said, including his criticisms of Galen, although these seemed to him somewhat exaggerated, but argued that the Fabrica, for all its merits, was doing nothing new. Vesalius had merely put into print what Massa and many others were already teaching — and had been offensive in his criticisms of those from whom he had learned most. Unmarried and ambitious, rich and with few obligations, Vesalius had the time to produce the definitive work on anatomy that a heavy medical practice and a large family denied to Massa and his other competitors. While there is a certain truth in this, no-one who has read Massa’s Introduction or, still more, ploughed through his medical correspondence has felt the need to bemoan a lost masterpiece.
Massa’s reaction was typical of the more pragmatic anatomists. Colombo, to Vesalius’ own disgust, immediately included the teachings of the Fabrica in his Paduan lectures, telling his students where he, Colombo, could improve on this new work. Fallopia also accepted Vesalius’ ideas, but was more honest in acknowledging his debts, even if he then went on to make a large number of criticisms and corrections. Others, like Fuchs, pointed out that Vesalius’ Epitome was too brief to serve as a introductory guide for medical students of anatomy, his Fabrica far too detailed and cumbersome. Hence there was a place for other, modest introductions to anatomy, like his own or that of Massa.
Very different, and far more vociferous, were the feelings of those who had been at the very forefront of introducing the new Galenist anatomy, some of whom, especially Guinther, Caius and Sylvius, had once been Vesalius’ friends and companions. The sense of betrayal must have added to their anger, and Guinther in particular could feel aggrieved at the unasked plagiarism of his own Introduction. Their rage is almost palpable in the furious strokes of the pen with which Cornarius, professor of medicine at Marburg and a leading translator of Galen, scored through the name of Vesalius at every point in his copy of the 1542 Froben reprinting of the collected works of Galen in Latin translation, now in the British Library. Vesalius’ name is expunged from the list of translators and correctors, and his errors are heavily marked down. John Caius went through his copy of the 1538 Greek edition of the collected works of Galen, now at Eton College, carefully recording in its margins the misunderstandings and foolish suggestions of ‘Wesalius’ in his translations and in the Fabrica.
Girolamo Donzellini (d. 1588), in a letter to the physician and botanist Pietro Andrea Matthioli written around 1560, described how Vesalius had angered all the leading physicians of Italy by his “immortal book.” He had provoked them by his language, and still more by his discoveries, and there were still some, almost twenty years later, who were still as hostile to Vesalius as they had ever been. The argument of these diehards, to judge from their criticisms, was expressed in a variety of ways. The first was simply factual: Galen had indeed largely dissected animals, but he had considerable experience of inspecting humans also. This was the primary argument used against Vesalius by Massa in his book review. John Caius listed on the first page of his Galen all the passages where Galen could be shown to have looked at a human body: others pointed to Galen's expressed awareness that he was having to rely on animal dissections for most of his description of the body. To deny this, as Vesalius seemed to do, was to fly in the face of the evidence. Alas for the defenders of Galen; while they were correct in their assertions, they did not appreciate the extent of Galen’s reliance on animals - and even Vesalius underestimated it.
Secondly, they pointed to many errors and misunderstandings of Galen’s Greek on the part of Vesalius. It ill behoved a man to make such damning criticisms of an author whose writings he could not properly translate. Sylvius, Caius and Cornarius eagerly seized on this proof, so they thought, of the incapacity of their opponent. It was compounded, in their view, by his unwillingness to accept fully one of the central tenets of the new Greek-based medical humanism: that the primary cause of alleged errors by Galen lay in the poor textual basis of the early printed editions and translations. By searching in libraries for Greek manuscripts, one could find many passages in which a manuscript preserved more accurate readings that corresponded better to what Galen had said than what had appeared in print. Scribal corruption over the centuries was responsible for making Galen appear more fallible than in fact he was. A good editor like Cornarius, so his Marburg colleague Dryander declared, could easily emend away those passages where Galen himself had been accused of error. This part of the argument had a great deal of plausibility to commend it. Manuscript hunters like Agostino Gadaldino and John Caius did discover older and more accurate manuscripts, and new finds were constantly being made: Galen’s On bones appeared in Greek for the first time only in 1543 and Caius himself published in 1544 the first ever edition of the first Book of On the opinions of Hippocrates and Plato. More investigation and better editing did appear to offer the possibility of a more accurate Galen. Yet, four and a half centuries of manuscript research later, the weaknesses of this approach are clear. Although, thanks in particular to material preserved in Arabic translation and hence unknown in the sixteenth century, modern scholars have at their disposal more extensive and better founded texts on anatomy than had Caius and Vesalius, improvements have been in details rather than in any overall conception or level of accuracy on the part of Galen. A few of Vesalius’ conclusions can be shown to be based on error, but these do not nullify his general contentions.
The third argument to preserve the infallibility of Galen had again a certain justice. Sylvius and, indeed, Fallopia argued that some of the differences between what Galen described and what Vesalius saw were due to a change in the actual body being examined. The noble Romans, a very different breed from modern degenerates, had a slightly different physique from their sixteenth-century successors. Just as one could breed dogs to produce different qualities, and, indeed, changes in their bodily structure, so it was possible to believe that nurture and environment together might combine to bring about alterations in the human body. Renaissance scholars were familiar with the Hippocratic passage in Airs, Waters, and Places, in which the author described how the tight binding of children's heads led first to the artificial production of long heads, and then over time to the generation of a race of long-headed individuals. But Renaissance scholars were not to know the fallibility of this account, or that genetic changes might take generations, and certainly far longer than Vesalius’ opponents assumed. Particularly in Sylvius’ attacks, the contrast between ancient nobility of mind and body and the degenerate present bore the appearance of a shrill reluctance to countenance any error on the part of Galen.
Finally, there were those who attacked Vesalius for his anatomical errors. Sylvius, Corti, and Caius all claimed to have seen structures whose existence had been denied by Vesalius. An anatomy of the senses was thus met by an identical claim to authority. Sylvius reported his experience in very many dissections, Caius likewise; Colombo and Fallopia equally pointed out errors of perception made by Vesalius, both when he failed to notice something and when he still adhered to Galen’s teaching. They rightly drew attention to instances where Vesalius might have mistaken something unusual for the norm, and Vesalius in the second edition of the Fabrica accepted many of these criticisms. But the result was less to discredit Vesalius, whose work was increasingly seen as marking a new epoch in anatomy, than to urge greater care in investigating anomalies, and in using comparative material.
As we have seen, Vesalius was not alone in demanding a leading place for anatomy in medical education; he was contributing to a trend, not setting it. His emphasis on using human corpses, where possible, was also one that was not unique to him, although the impact of the Fabrica undoubtedly inspired many to follow him, and contributed to the general acceptance of human dissection beyond Italy. Dissections drew large crowds in Bologna, Pisa, or Heidelberg; temporary booths, such as had been described by Benedetti, were replaced by permanent anatomical theatres, e.g. in Padua; and condemned criminals, particularly if they came from afar, were likely to end up on the anatomist's table within hours of their execution, a contribution to a public spectacle as well as to medical science.
But one caveat must be entered here. There were never enough bodies to go round to supply all the needs of professors and students. Even when, as at Wittenberg in the second half of the century, the pursuit of human anatomy was strongly encouraged by the authorities of both church, state and university, there were often difficulties in obtaining suitable bodies. There were certainly never enough for students to be able to enjoy the same “hands-on” experience that Vesalius advocated. Two solutions were commonly followed. The first was for the professor to concentrate on skeletal anatomy, where the same bones could be reused for several years in teaching about, for example, the skull. The second was to carry out more and more dissections, but on animals, especially cats and dogs. Provided that one was aware of what one was actually doing, as indeed Galen himself had been, then one could gain an understanding of human anatomy through comparative anatomy. Volcher Coiter’s work on anatomy in the late 1560s and early 1570s and still more, the major series of investigations into individual organs or groups of organs by the Paduan Professor Fabricius of Aquapendente (1533–1619), testify to the sophistication reached by comparativists in response to the methodological challenge laid down by Vesalius. They were still carrying out dissections of both humans and animals, as Vesalius himself had done, but they were now conscious of the pitfalls involved in linking the two together.
To assess the impact of the Fabrica on anatomical drawing is far from straighforward. Although Vesalius’ plates had undoubtedly contributed to the great success of the book, as Massa acknowledged, they brought their own problems, not least that of cost. Few anatomy books for students had more than a few plates, and none were as lavishly illustrated as the Fabrica. But although the illustrations were both clear and beautiful, they carried a visual message that not every anatomist was willing to accept unhesitantingly. Massa was far from alone in identifying the difficulty. Concentrating solely on a sensate anatomy, describing only what one could see or feel, was to minimise the whole purpose of anatomy teaching. As well as description, one needed discussion — of how the bodily part worked and how it related to the other operations of the body. Function was at least as important as form, and that required verbal exposition, not just observation. If the duty of the teacher of anatomy was to explain the body, then Vesalius had left his task only half done. Besides, if, as he had repeated, illustration was required to supplement a verbal description, then greater clarity of exposition would automatically reduce the necessity for a visual image. Not every leading anatomist included plates in his anatomical treatise. Although Realdo Colombo had in 1548, in not earlier, dissected in the presence of an eminent painter, illustrations are absent from the text of his 15-book anatomical treatise of 1559, although his frontispiece shows an artist drawing while he dissects, and a spectator comparing the open viscera of the corpse with a crude full-page drawing in a large folio volume (the Fabrica ?). The unauthorised Lyons re-printing of the Fabrica in 1552 in two volumes with a much smaller format includes only one set of illustrations, those of the skull, on pp. 130–132.
The impact of Vesalius’ illustrations, however, was not entirely beneficial. Their very success as images seems to have driven out competitors. While the new Catholic emphasis on realistic naturalism in art, advocated by the almost contemporary Council of Trent, undoubtedly encouraged young artists to turn to anatomical drawing, for a generation after 1543 it is the Vesalian plates that dominate. Compared with the plurality of images and styles before 1543, this was a regression. Canano’s planned atlas of copperplate engravings did not get beyond the first part, published in 1541–1542; the plates for Eustachius' anatomical textbook, which were ready by 1552, did not appear in print until 1714.
Instead, there came a whole series of plagiarisms or crude copies of the plates to the Fabrica or Epitome. In 1545 Thomas Geminus in England copied the plates from the Fabrica and a version of the text of the Epitome for his Latin Compendium of Anatomy. A Spanish anatomist Bernardino de Monserrate took over some of the plates, crudely drawn and much reduced in size, for his short introductory text on anatomy in 1551, the same year that Geminus’ book was itself copied in Augsburg. The celebrated French surgeon, Ambroise Paré, was another who copied, in this instance much more crudely, Vesalius’ illustrations for his own Anatomy of 1561. Most provocative of all was the takeover of Vesalius’ plates by the Spanish anatomist, Juan Valverde de Hamusco, who was active in Rome and a friend of Colombo. His Historia de la composicion del cuerpo humano appeared in Rome in 1556, but went through several later editions in Italian, Latin and Dutch. His illustrations were much reduced in size, and were crudely drawn, and, according to Vesalius in 1561, accompanied a text written by a man who had never dissected himself and who was ignorant of the very principles of medicine and the liberal arts. It was no more than a pot-boiler, issued solely with an eye to profit. If that was so, Valverde was a shrewd investor. His book was much smaller than the Fabrica, yet much larger than the Epitome. Vesalius considered it superficial, yet others judged it much more favourably. Fallopia, for example, thought it worthy of special praise for its brevity and for its illustrations, which made it ideal for a student market. Its smaller size and weight made it more easily portable than the Fabrica, and subsequent reprints incorporating the Epitome increased its didactic value still further. If the Fabrica was aimed at a wealthy market, it was Valverde's revision that triumphed among the average physician and surgeon, not least because it was published in so many vernaculars.
One further development should be noted, the burgeoning of the fugitive anatomical sheets in various manifestations and languages. This was the way in which anatomical knowledge was most easily transmitted to the widest possible readership. Vesalian anatomy took time to appear in this form, and some of his images, especially the Adam and Eve figures of the Epitome, were more easily assimilated than others. The Wittenberg printer Simon Gronenberg went one step further. In his set of anatomical sheets, “intended for those studying Melanchthon’s On the Soul,” the male figure bears a recognisable likeness to the portrait of Vesalius in the Fabrica. In a trope so characteristic of the sixteenth century, the anatomist is himself anatomized. His final service to his readers is become himself his own subject; it is his body that is laid open, to be peered at by enquirers. He has, in short, become the ultimate anatomical icon.