Leonardo belongs to the very small group of painters who are as famous for their personalities or their lives as for their work. The basic elements of the legend are already present in the biography produced by Vasari in 1550: his precocious and prodigious talent, the range of his interests, his extraordinary physical beauty and charm, which could persuade people of his ability to carry out even the most extravagant schemes, his lack of religious belief, his love of animals, his reluctance to follow a conventional career, his unsystematic manner of working, and, finally, his death in the arms of Francis I, King of France. Vasari had much less to say about Leonardo’s works. He provided a long and rather misleading description of the Mona Lisa, which had left Florence well over thirty years before, and shorter references to works in private hands, none of which can now be identified apart from one drawing. But the only picture on public display he mentioned was the Last Supper in the refectory of the monastery of Santa Maria delle Grazie in Milan, which he praised in enthusiastic terms. At that time Vasari himself had never seen it, but when he did so, sixteen years later, he complained that it was no more than an “indistinct smudge.”
In Vasari’s account Leonardo was the founding father of modern painting, the equal of Raphael and Michelangelo, and other writers of the time were no less laudatory. But for the next three centuries his name was overwhelmingly associated with a single picture, the Last Supper, which was painted shortly before 1500, and which had already begun to deteriorate by 1517, according to a contemporary witness named Antonio de Beatis. The composition was known from numerous copies and prints, and it was universally regarded as one of the supreme masterpieces of Italian painting, even though tragically damaged. Thus at least from the middle of the sixteenth century visitors have always brought to it a mass of expectations and preconceptions, approaching it in much the spirit of pilgrims revering a religious relic. It is indicative of its special status that travelers and connoisseurs paid little attention to a much better preserved work by Leonardo in Milan, the Virgin of the Rocks, now in the National Gallery in London, which for centuries was his only other painting on public display anywhere in Europe.
Admiration for the Last Supper was almost always combined with a sense of disappointment and loss. In 1572 Serafino Razzi called it “half ruined and flaking,” while Gian Paolo Lomazzo, a few years later, again remarked that it was falling off the wall. Francesco Scannelli, who saw it in 1642, reported that by then only a few traces of the figures were preserved, that in large part they were no longer attached to the wall, that areas were exceptionally dark, and in general that one could scarcely make out the subject. Writers of the later seventeenth and early eighteenth century were equally negative about the condition, with Jonathan Richardson Sr., for example, observing in 1722 that in places there remained only bare plaster. Indeed by that period many travelers did not mention Leonardo’s painting at all, presumably because it no longer seemed worth visiting.
The situation changed in 1726, with the first recorded restoration, by a painter named Michelangelo Bellotti. He evidently managed to alter the appearance of the picture dramatically, and although he claimed that this was thanks to a secret method of cleaning, at least one observer, named De la Condamine, who saw it in 1754, concluded that the picture must have been entirely repainted.
Bellotti’s restoration was followed by seven others, and it was probably preceded by limited interventions of which no records have come to light. In almost every case these restorations have been controversial, with some observers claiming that Leonardo’s original had been miraculously recovered, while others deplored the supposedly irreparable damage that had been inflicted on it. Eighteenth- and nineteenth-century restorers tended to be secretive in their methods as well as casual about keeping records, so it is difficult to reconstruct exactly what happened, a problem compounded by the nineteenth-century practice of touching up photographs.
It is only for the last two restorations, the first by Mauro Pellicioli, after World War II, and the second by Pinin Brambilla Barcilon, completed after more than twenty years of work in 2000, that adequate records are available. These two restorations were undertaken in very different circumstances and with different intentions. Pellicioli was faced with urgent problems caused by the destruction of the refectory by a bomb. His first priority was to fix the unstable paint surface, which was flaking off the wall. He then cautiously removed overpaint where this seemed to obscure the original pigment; but he left large areas intact, in an attempt to achieve a more or less uniform effect. Barcilon, by contrast, working over a far longer period, tried to remove almost all the work of earlier restorers, except in areas, such as the ceiling, where the original had entirely disappeared, in order to expose as much of Leonardo’s paint as could still be found.
As is abundantly clear from the superb photographs in Leonardo: The Last Supper, which is a report on the restoration along with a short history of the painting, Leonardo’s own work now consists of a mosaic of small fragments, like a jigsaw puzzle with most of the pieces missing. Although estimates are necessarily subjective, in total it looks as if only about 20 percent of the original paint still survives; and while critics have claimed, not necessarily correctly, that some of Leonardo’s pigment was itself lost in the latest restoration, it seems beyond dispute that most of it disappeared long ago. If the accounts of the early writers are to be trusted, much of the damage must have occurred well before Bellotti’s restoration of 1726.
What is more, it is evident that even where Leonardo’s paint exists, the upper layers have been lost. The clearest evidence for this is provided by seven strips of blue embroidery at each end of the tablecloth, which seem to include some of the most intact areas of original pigment. In the fifty or so known copies of the Last Supper made before the late eighteenth century, in the form of paintings, drawings, and prints, some of them dating from Leonardo’s own lifetime, only one includes embroidery at all. But this feature is visible in all known copies dating from about 1790 or later. Of the early copies the exception is a picture first recorded at Ecouen outside Paris around 1750, which shows five strips of embroidery, not seven, and these are black, not blue. That all the artists responsible for the other copies would have omitted such a conspicuous feature is not remotely credible, so it would seem either that the embroidery is not original, which is difficult to believe, or that it was eliminated by Leonardo himself and then revealed during one of the two restorations in the eighteenth century, probably the second, undertaken by a painter named Giuseppe Mazza, who worked under the misconception that Leonardo had used fresco.
Presumably the Ecouen copy, which was in the Louvre from just before 1800, was itself restored at some stage, when this feature was added. The upper layer of Leonardo’s paint has also disappeared from the drapery of Simon, the apostle at the extreme right. The early copies show that he had a red robe over his right shoulder, but this is now almost entirely white, because only some of the underpaint has survived.
Since the original surface of Leonardo’s masterpiece is gone, while only patches of the lower layers have been preserved, to all intents and purposes the Last Supper no longer exists and has not existed for centuries. Faced with this problem, Barcilon and her assistants have not tried to conceal the damage, as so many of their predecessors did, but have reconstructed the missing areas in such a way as to make a distinction between what is original and what is new, by indicating the original contours, which can be established with the help of early copies, and filling the spaces between the areas of Leonardo’s paint with watercolor of the same general hue, but lighter in tone. When the latest restoration was begun, the intention was simply to reveal everything by Leo-nardo, eliminating the rest, but so little was preserved that this option turned out to be unrealistic.
It is now possible to see more clearly than before the structure of the painted space, including the floor, as well as the poses of the figures, while the objects on the table have acquired a new precision. But the tonality is certainly much less intense than Leonardo can ever have intended, the range of color much more limited. Nor has any attempt been made to recreate the extreme subtlety of the modeling so evident in the copies and in Leonardo’s surviving paintings. The effect is as if the original picture had faded. This of course is not what happened, but the solution is an ingenious one, and arguably the most intelligent in the circumstances.
It has been pointed out, with some justification, that the result does not look like any Renaissance painting, but before restoration the Last Supper did not look like a Renaissance painting either, and the only way to have given it such an appearance would have been by undertaking a far more radical repainting on the basis of the surviving copies. This could certainly have been done, but it is difficult to believe that it would have met with wide approval or would have served any useful purpose. An alternative would have been to do nothing at all, or at least to have done the bare minimum required to maintain the picture in roughly the state left by Pellicioli. Such a course of action would have saved a great deal of time and labor. It would also have preserved an image which, however false to Leonardo’s intentions, was extraordinarily famous and which, because of its historical associations, had a potency of its own.
But even assuming that the painting itself was stable, which has been denied, the case for keeping a particularly damaged and misleading copy, painted by several artists, apparently from 1726 onward, does not seem strong. The arguments used to justify restorations in the past, after all, have been, first, to prevent further deterioration and, second, to reveal what remained of Leonardo’s own work; and in these respects the present restoration has had similar goals.
It is inevitable that comparisons have been made with another controversial Italian restoration of an equally famous Renaissance masterpiece, Michelangelo’s ceiling of the Sistine Chapel, but the issues involved are quite different. The Sistine ceiling is painted in fresco, that is to say with water-based pigment on plaster. While the restorers left the very durable pigment painted on wet plaster, they removed virtually everything else. What remains is certainly all by Michelangelo; but the question is whether the material that was removed consisted only of dirt and the additions of earlier restorers, or whether it included large areas of pigment applied by Michelangelo to the plaster after it had dried, principally to indicate shadows. Although it was initially claimed that the Sistine ceiling had been repeatedly restored in the past, no significant evidence of this has come to light.
Leonardo, by contrast, did not use fresco at all, but painted in a combination of egg tempera and oil on a smooth layer of gesso. He did so in order to achieve the kind of luminosity, detail, color range, and subtlety of modeling typical of painting on panel. Unfortunately, because it proved impossible to protect the wall from damp, the paint surface soon began to deteriorate, and successive attempts to halt or reverse the process proved unsuccessful. Thus while it is generally agreed that Michelangelo’s work on the Sistine ceiling had survived virtually intact up to the latest restoration, and while defenders of the restoration claim that it is still intact today, the Last Supper has been a ruin for centuries.
By the removal of dirt and overpaint, and with the help of early copies, enough has been recovered of Leonardo’s painting to give some sense of how startling the original must have been, in the way in which the wall surface seemed to open up to a deep space behind, in the scale of the figures, and in the eloquence of the gestures. But at the same time, particularly because of the reconstruction of the floor in Leonardo’s painting, one can see more clearly than before the truth of the common observation that his attempt to unite the space of the refectory itself and the painted room on the wall was not entirely successful. The most obvious reason is that he set the vanishing point of the painting four meters above the real floor, probably in order to show the surface of the table. But that meant, for the spectator in the rectory, that the painted floor seems to slope steeply upward, making the table appear dangerously unstable. This is not evident in photographs, which are not normally taken from the eye level of such a spectator. The idea of showing a very deep painted room is also troubling, because the side walls do not appear as extensions of the real walls of the refectory, but bend sharply at the picture plane.
It was evidently to avoid this kind of problem that copyists often reduced the space between the table and the back wall or eliminated the ceiling; and similar solutions were common in later representations of the same subject, as one could see in the exhibition in Milan about the origins and influence of Leonardo’s masterpiece. Perhaps a more satisfactory effect could have been achieved if the Last Supper were lit from the left, as Leonardo intended, rather than from below, as at present. The current system of display, with the painting visible only from a distance, behind a row of concealed lights, and the refectory itself dimly lit, is designed for dramatic effect, but it is entirely misleading.
One lesson that emerged very clearly from the exhibition was that, in comparison with earlier representations of the Last Supper, Leonardo’s was the first to turn it into a dramatic event, the response of the apostles to Christ’s declaration, as quoted by Matthew, “One of you shall betray me,” a text which is included in the earliest engravings and which is cited in connection with the picture by Leonardo’s friend Luca Pacioli. Despite this evidence there have been repeated suggestions that he also simultaneously alluded to the other famous episode of the Last Supper, the Institution of the Eucharist, that is to say Christ’s declaration “This is my body—this is my blood,” because Christ’s hands are not far from a glass of wine and a roll of bread.
The idea, which is not discussed very clearly in the catalog, dates from the 1960s, when art historians were fond of detecting many levels of meaning in Renaissance paintings, but in this instance the approach seems particularly implausible. Not only does it make Christ’s own action and the response of the apostles ambiguous and incoherent, it is contradicted by the text of Matthew, who places the Institution of the Eucharist after the revelation of the betrayal, and it is difficult to reconcile with the fact that Leo-nardo omitted the one indispensable element of the Eucharist, namely the chalice, which was regularly included in depictions of the Institution. The table is full of fruit, rolls, and wine glasses, so Christ’s hands had to be in proximity to them; but it is difficult to believe that Renaissance Christians would have associated the Eucharist with a half-drunk wine tumbler. In any case, the eucharistic theme, though regularly shown in altarpieces for obvious reasons, was not regarded as appropriate for refectories.
In a manner without obvious precedent, Leonardo conveyed the emotions of the apostles both through a highly artificial and studied language of gesture and by an extraordinary concentration on physiognomy and facial expression, as one can see from the few surviving preparatory drawings. One of the earliest published anecdotes about the artist, recounted by the tragedian and literary theorist Giambattista Giraldi in 1554, describes his difficulties in finding a suitable model for the head of Judas, which alone was still unfinished. When the monks complained to the Duke of Milan that he had done nothing for a year, Leonardo retorted that every day he spent two hours among the criminals of the city, looking for someone whose features would be appropriate, and added that he would use those of the prior of the monastery unless he stopped pestering him. But however much in this respect Leonardo’s emphasis on distinctive expressions may have impressed his contemporaries, it was not much followed by later artists dealing with the subject, partly because the faces of the apostles soon lost their original definition, as is evident from the accounts of the picture’s condition from the time of Vasari onward, and also because in the hands of a less accomplished artist it could easily degenerate into caricature. But the gestures of the figures retained their power as the painting deteriorated, and it is these that have made the work so memorable.
Whereas in his lifetime and for the next three centuries or so, Leonardo’s reputation was based almost exclusively on his activity as a painter, he is now equally famous for his other interests, which have been accessible since the publication of his notebooks. These owe their preservation largely to the fact that they were written by a very famous painter and that they contained a large number of beautiful drawings. Until shortly before 1800 only the drawings and Leonardo’s observations on painting attracted any interest. These notes were copied at a relatively early date and published in 1651 in France. The title then given to them, Treatise on Painting, is somewhat misleading, because Leonardo never arranged his ideas in a coherent way. And even when they were published, there was much disagreement about their value. Poussin, for example, who knew the material well, since he had provided illustrations for one of the manuscript copies, memorably claimed that everything of value could have been written on a single page, in large letters.
The idea of Leonardo the scientist starts in 1797, with the publication of excerpts from the notebooks, and from that time onward this aspect of his activity has attracted increasing interest. This is partly because history painting as such, on which his reputation was founded, has lost much of its prestige, and partly because of the appeal of his drawings. But perhaps most important is the attraction of the notion of a genius whose ideas were far ahead of his time. It is significant in this respect that both Sherwin B. Nuland and Michael White, although providing general accounts of his career, choose to concentrate on Leonardo the scientist, so much so that neither includes any reproductions of his paintings, apart from one detail illustrated by White. The book by Nuland, a professor of surgery, is much the better of the two, not least because he chooses to concentrate on Leonardo’s study of anatomy. His own professional expertise enables him to write with particular insight and authority about the artist’s many discoveries in this field, for example regarding the structure and functioning of the heart, since he is able both to explain their significance and to describe the practical difficulties Leonardo faced in carrying out his dissections and making sense of what he saw.
White’s text is more wide-ranging but also much more superficial. His understanding of the historical background is rudimentary, so that he claims, for example, as an instance of “the general lasciviousness of the age during which Leonardo was writing” his notes on human reproduction, that Pope Alexander VI had an illegitimate child by his own daughter Lucrezia Borgia, whom he believes was sleeping with her elder brother, Cesare. Here, as elsewhere, he makes no distinction between historical fact and pure invention, and this is true also of his treatment of many episodes in Leo-nardo’s own career, which would be more appropriate in a work of fiction (“Leonardo was something of a country bumpkin, with rough manners and a pronounced rural accent; but Verrocchio was no snob”). Some of his attempts to explain Leonardo’s achievements in modern terms are also unhelpful, such as the suggestion that the illustrative method used in his anatomical drawings involved “a form of what we would now call hyper-text and the cutaway, layering technique used in the creation of CD-ROMs.”
Like many previous writers on the topic, both authors tend to emphasize those observations of his that have been confirmed by later research; they more or less take for granted that Leonardo worked largely alone and that he was unique in his time in the kind of investigations that he undertook. There may be some truth in both contentions, but given that his notes were preserved because he happened to be Leonardo, rather than because of their content, we are scarcely in a position to say whether others at the time, whose notes have not survived, might have been working on the same subjects.
Although we now tend to make a clear distinction between Leonardo’s activity as a painter and his investigations of aspects of the natural world, this is in one important respect misleading, because these investigations grew out of his work as an artist and were in fundamental ways conditioned by it. The subjects that he chose to study, such as technology and weapons, optics and anatomy, were of interest to many artists and military engineers, professions that were often combined in the Renaissance. Thus Leonardo’s preoccupation with machines, lifting devices, or weapons can be paralleled in the work of various fifteenth-century artists and engineers, such as Francesco di Giorgio or Mariano Taccola, while Piero della Francesca produced a highly systematic treatise of lasting importance on perspective, Ghiberti was interested in optics, and other Florentine artists are known to have carried out dissections. Leonardo carried his inquiries much further than any of his known predecessors, but he belongs in this tradition, much more than in that of conventional scientific study, insofar as it existed at that time.
The basis of most scientific knowledge in his day was the body of texts that had been transmitted from antiquity and from the Arabs, much of which was only accessible to those with an understanding of Latin, and for certain topics also a grounding in mathematics. Leonardo’s competence in both these fields was very limited. In one way this was an advantage, because he was less constrained than he might otherwise have been by conventional ideas; but at the same time in certain matters he was unaware of work that had already been done, relying as he did almost exclusively on texts in the vernacular.
As one would expect, his attitude toward established ideas was both dismissive and defensive. His own approach to almost every kind of inquiry that he undertook was deeply dependent on the one unique skill that he possessed, the ability to draw in a far more accomplished way than anyone before him anywhere in Europe and probably anywhere in the world. Unlike those who had investigated nature previously, Leonardo was able to draw what he saw accurately, and he developed new techniques for the representation of complex machines and above all of human anatomy which had the potential for transforming the study of these subjects. At the same time, he had remarkable patience, exceptional curiosity, and great ingenuity in developing experimental techniques, such as the use of wax injected into the ventricles of the brain to establish their exact shape. Again, as Nuland points out, Leonardo’s idea of immersing the eye in egg white and boiling the whole, in order to make it easier to dissect, anticipates standard modern techniques for the “accurate slicing of fragile structures.”
With these unprecedented gifts, it is not surprising that he made a number of fundamental discoveries, especially in anatomy. What is more surprising is that none of these discoveries, so far as is known, had the slightest influence on the history of scientific knowledge, because they remained locked in his notebooks until centuries after his death. This cannot simply be explained on the grounds that Leonardo was snubbed by the scientific community because of his lack of a conventional higher education. He was, after all, one of the most famous men of his day, favored and supported by the Duke of Milan, the brother of Pope Leo X, and the King of France; and with backers like this, he would surely have had access to anyone he wished to meet. What is more, he was certainly on friendly terms with Luca Pacioli, one of the leading mathematicians of his day, even providing him with drawings of regular solids which were then published. Yet he did not collaborate with any physicians, in the way that, a generation later, the Flemish artist Jan Calcar collaborated with the great anatomist Andreas Vesalius to produce illustrations of the human body which transformed European medicine.
Leonardo, then, does not seem to have had much interest in making his discoveries known, or in collaborating with others. The simplest explanation for this is that his privileged status depended on persuading his patrons that he possessed a unique body of knowledge and a unique range of skills, for he was not simply employed as an artist but also devised court entertainments of every kind and acted as consultant on various engineering projects. To have shared his hard-won knowledge would have been to undermine his own position.
But there is perhaps also a subtler reason. Leonardo was an autodidact, with only limited formal education. He had no direct experience of the higher learning of his contemporaries, no real understanding of the way in which the growth of knowledge was a cumulative and collaborative process, as was so evidently the case with the major intellectual enterprise of his time, the recovery of the heritage of classical antiquity. He took the trouble to preserve his own papers, which represented his own accumulated intellectual capital; but he was much less concerned about increasing the intellectual capital of the society in which he lived, because he did not fully appreciate its value. And in this respect at least, he was very different from the later scientists with whom he is so often compared.
The one field in which he was historically important, of course, was as an artist; and while the history of science and technology could be written without him, the history of art could not. It is because of his artistic gifts that so many of his notebooks were preserved and that they are still studied today. Yet it is a curious irony that his artistic legacy has survived much less well than his scientific investigations. The Last Supper has all but disappeared; the other major project of his years in Milan, his full-size clay model for an equestrian monument, was destroyed by invading French troops in his own lifetime; and his other mural painting, the unfinished Battle of Anghiari for the Palazzo Vecchio in Florence, also vanished a few years after he abandoned work on it in 1506. But it was the fame of these works, which we can no longer see, rather than that of the Mona Lisa or the Virgin of the Rocks, that established the reputation that he has enjoyed ever since.
August 9, 2001