A second Leonardo masterpiece?

The BBC has an article by Alastair Sooke, art critic of The Daily Telegraph, about a (maybe) second Mona Lisa:

One of the surprising things about Leonardo da Vinci is that, despite his colossal reputation as an artist, he didn’t actually produce many paintings. Over the course of a long career, lasting almost half a century, he began probably no more than twenty pictures. Only fifteen have survived that scholars agree are wholly his.
So the discovery of a new painting by Leonardo would be a very big deal indeed. According to recent reports, a picture by the nineteenth century French artist Paul Gauguin has been sold privately for a record-breaking three hundred million dollars. Imagine how much an authentic Leonardo could make if one ever came to the market.
The thing is, attributing artworks to Leonardo is notoriously difficult. One painting currently touring cities across Asia exemplifies what I mean. It used to be known as the Isleworth Mona Lisa, but its current owners have rebranded it the Earlier Mona Lisa, because they believe that Leonardo himself painted parts of it a decade or so before beginning arguably the most famous picture in the world: the Mona Lisa in the Louvre in Paris, France.
In December of 2014, the Isleworth painting went on show to the public in an exhibition at the Arts House at the Old Parliament building in Singapore. In March of 2015, it will travel to Hong Kong before arriving in China and then visiting other destinations in Asia.
At first glance, it is remarkably similar to the Louvre’s Mona Lisa. A woman with dark hair and an enigmatic smile sits at a slight angle to the viewer on a loggia opening onto a panoramic landscape. Except this woman is obviously much younger than the subject of the Louvre painting. If Mona Lisa had been painted a decade earlier, then this is how she would appear.
So what is this unusual picture? A curious, sexed-up copy of Leonardo’s masterpiece? Not according to the Mona Lisa Foundation, a Swiss non-profit organization leading research into the painting on behalf of the anonymous international consortium that owns it. Three years ago, the foundation convened a press conference in Geneva, Switzerland at which they presented “the results of thirty-five years of research and convincing arguments” suggesting that the painting was in fact an earlier portrait of Mona Lisa, which Leonardo had left unfinished.
The event sparked headlines around the world. Here, it seemed, was a newly discovered, authentic Leonardo. How exciting! But, the day after the press conference, Leonardo expert Martin Kemp, emeritus professor of art history at the University of Oxford in the UK, published a blog post rubbishing the foundation’s claims, and explaining in detail why he considered them to be erroneous. Perhaps the idea of a second Mona Lisa was too good to be true.
In fact, art historians had known about the Isleworth Mona Lisa for some time. Shortly before World War One, the maverick English connoisseur Hugh Blaker spotted it in an old manor house in Somerset, where it had hung for more than a hundred years, having been bought in Italy as an original masterpiece by Leonardo.
Sensing something special beyond the covering of dirt and varnish, Blaker acquired it and brought it to his studio in Isleworth in west London (hence the painting’s moniker). Not long afterwards, his stepfather, John R. Eyre, published a monograph proposing that Leonardo had worked on two versions of his portrait of Mona Lisa, and that the Isleworth picture was the first one. The ‘Isleworth Mona Lisa’ appears to depict Lisa Gherardini about ten years earlier than the Mona Lisa that hangs in the Louvre.
The painting was subsequently bought by the American collector Henry F. Pulitzer, who in turn published a self-serving book arguing that the Isleworth picture was in fact Leonardo’s only real portrait of Mona (short for Madonna) Lisa Gherardini, wife of the Florentine merchant Francesco del Giocondo. (Pulitzer concluded that the Louvre painting was an idealized portrait of someone else.)
Yet despite all this theorizing, the idea that the Isleworth Mona Lisa was actually by Leonardo never gained traction with important scholars. In 1979, following Pulitzer’s death, the picture disappeared inside a Swiss bank vault, where it remained until 2008, when it was acquired by the consortium that now owns it.
At the same time, the Mona Lisa Foundation was established to investigate the question of the picture’s attribution to Leonardo. According to its vice president, the stamp dealer David Feldman, the foundation “does not have any stake in the painting” and endeavors “to examine facts in the most objective light possible”. However, he would not comment directly when asked if there was any overlap between the owners of the painting and the foundation’s board. And to the question of whether the consortium’s ultimate goal was to sell the painting as a real Leonardo, he replied: “I cannot disclose any information relating to the consortium.”
Like Eyre and Pulitzer before them, the current owners of the Isleworth painting are convinced that it is, in part, by Leonardo. Yet, like Eyre and Pulitzer, they are struggling to convince leading scholars. As well as Kemp, other respected Leonardo experts, including the German art historian Frank Zollner, deny that there is any substance to their claims. Why?
The foundation interprets historical evidence including written sources, as well as the fact that Leonardo sometimes created multiple versions of the same picture, such as the Virgin of the Rocks, to contend that he painted two portraits of Mona Lisa: one that was commissioned around 1503 by her husband Francesco; the other a decade later by the artist’s patron Giuliano de’ Medici.
Some who believe that Leonardo did paint the Isleworth Mona Lisa still admit someone else must have painted the inferior background. This would account for the younger appearance of the woman in the Isleworth painting. It would also explain why Raphael, who made a sketch probably from memory around 1505 after seeing the painting in progress, showed the sitter flanked by two columns. Similar columns are visible in the Isleworth picture, but only their bases appear in the painting in the Louvre, which has never been trimmed.
Admittedly, it is awkward that the support of the Isleworth picture is canvas, when Leonardo usually painted on wood. But the foundation points to the fact that the artist did occasionally paint on canvas, witness his tempera study of drapery on linen canvas in the Louvre, which dates from the 1470s, when Leonardo was still making his name. (This is, however, an exception to the general rule: Leonardo’s mature oil paintings, including the Louvre’s Mona Lisa, were executed on wood.)
In addition, the foundation has collaborated with scientists to help build its case. Feldman says that research physicist John Asmus of the University of California has run “a series of peer-reviewed scientific tests” determining “with ninety-nine per cent scientific certainty that the same artist painted at least the face of both the Isleworth and Louvre Mona Lisas. Accordingly, if one denies that the Isleworth is by DaVinci, then one also denies the Louvre version.”
The foundation therefore concludes that Leonardo was responsible for the face and hands of the woman in the Isleworth picture, while an inferior artist must have painted the clumsy landscape in the background.
Among Leonardo scholars, however, the ‘two Mona Lisas’ theory remains moot, and that’s before the particular merits of the Isleworth picture are evaluated. Kemp believes that Leonardo only ever began one painting of Mona Lisa, which he then worked on intermittently until his death. While the foundation interprets revisions in “under-drawings” discovered during infrared analysis of the Isleworth painting as a sign that it must be an original work, Kemp argues that they “do not reveal any of the characteristics of Leonardo’s preparatory methods”. When I contacted him recently, Kemp reaffirmed his belief that the Isleworth picture is a later, “stilted” copy.
Although Kemp has closely scrutinized (and questioned) the evidence provided by the foundation, he has never actually studied the painting firsthand. Feldman told me that, despite an invitation, Kemp “refused” to examine the canvas before the foundation announced its findings in 2012.
The Louvre’s Mona Lisa is arguably the world’s most famous painting and has survived numerous attempts at theft and vandalism.
But, says Kemp, “I have not ‘refused’ to see it. I decided not to because I only go to see works (at my expense and never for remuneration) if the evidence I have– documentation, provenance, digital images and scientific examination– convinces me that it is worth the time, travel, and expense.” In the case of the Isleworth painting, he saw “nothing to convince me that seeing it in the flesh is of high priority. I am sent many non-Leonardos– as many as one a week– and have to make choices. If I travelled to see every hopeful ‘Leonardo’, I would be impoverished.” He adds: “If they want to bring the painting to me, they can.”
To gain a fresh perspective on the story, I invited the British scholar and leading Leonardo expert Luke Syson to comment on it. In 2011, Syson, who now works at the Metropolitan Museum of Art in New York City, oversaw the blockbuster exhibition Leonardo da Vinci: Painter at the Court of Milan, at the National Gallery in London. The climax of the show was the introduction to the public of an oil-on-walnut picture of Christ as Salvator Mundi, Savior of the World.
Following intense analysis, art historians now agree that Leonardo painted it, making it the first “new” Leonardo for a century. (Incidentally, like the Isleworth Mona Lisa, this painting, which was previously thought to be a copy after a picture by one of Leonardo’s pupils, has been known since the start of the twentiety century.)
In other words, Syson knows a thing or two about attributing paintings to Leonardo. He is one of a handful of international scholars with well-established reputations as authorities on Leonardo whose backing the foundation would ideally like to secure.
Like Kemp, Syson has not seen the Isleworth picture in reality though, as he says, “I have never been asked to view it, and that fact may in itself be revealing. A serious campaign to introduce a new work by a great artist would ensure it was shown to all the principal experts.”
But on the basis of published photographs of the picture, he has “never taken these claims seriously. In all honesty, one doesn’t in this instance need to see the work in the flesh to judge this Mona Lisa a rather poor, somewhat later copy, one of dozens that were made of this famous picture in the centuries that followed its creation.”
Syson says that “lots of the details are misunderstood” and points out that the canvas support “would be very off the mark for Leonardo, who typically painted on wooden panels. But most important it’s simply not good enough to be by Leonardo himself. This is just the most recent of many attempts made by optimistic owners to prove their copies of Leonardo’s pictures are by him, wholly or ‘in part’.”
Moreover, Syson does not accept that scientific evidence can conclusively settle debates over the authenticity of pictures such as the Isleworth Mona Lisa. “The bringing in of science– sometimes pseudo-science– is increasingly a feature of such claims,” he continues. “Even if the science is good, it can never prove an attribution (though it can sometimes disprove it); it’s only ever one of several factors we’d use to assess the authenticity and authorship of a work of art. The picture needs also to be of the right quality, and to contain the characteristic thought and ‘hand-writing’ of the artist.”
Syson notes that Leonardo’s workshop did produce copies of his paintings, sometimes imitating his every change as he executed the original. “But this picture, to judge from available photos, and the fact it was painted on a canvas support, doesn’t come into this category. The story ignores art history, denies the principles of connoisseurship, and bypasses the experts. The whole thing is a little sad, especially for anyone visiting the display who is hoping to see a masterpiece by Leonardo.”
The Mona Lisa Foundation, of course, disagrees with this position. “We at the foundation find it hard to accept that there can be valid points of view against something which is now proven scientifically,” says Feldman, who also cites “public feedback” in Singapore that the Isleworth picture must be by Leonardo. However, advances in art history are determined not by public vote but by consensus among experts. And in the case of the Isleworth Mona Lisa, the foundation still has much to do in order to win more support among people whose opinions really count.

Rico says there's an old adage about never buying a painting, the copy of which hangs in the Louvre, that applies here...