There is something irresistibly attractive about the idea of experts making fools of themselves, which must be why this book was news before it had even been published. Its big idea is that considerably more than half of the drawings customarily attributed to Michelangelo are not by him, or, as one headline tantalisingly had it, “Spot the difference: one of these Michelangelos is said to be fake.” Since the “fakes” in question include various treasures of the Royal Collection and the British Museum, there is a great deal at stake here. Or rather, there would be, if the book’s authors – three German academics – came close to proving their case.

At 18in high, Michelangelo: Complete Works will defeat most bookshelves. It is opulently and beautifully illustrated, not least with magnificent details of the relatively recently (and dramatically transformed) frescoes on the Sistine Chapel ceiling and the Last Judgment on the end wall, but also with atmospheric black-and-white images of most of the sculptures. The short and instructive texts connected with these sections, and indeed with Michelangelo’s architecture, are entirely unobjectionable, but notably cautious in matters of attribution where there is any room for doubt.

No other Renaissance artist’s life and works are anywhere near as fully documented as Michelangelo’s, and he was the subject of extensive biographical attention during his long lifetime. A substantial biography of Michelangelo appeared in the first edition of Vasari’s Lives of the Artists of 1550, and was swiftly followed in 1553 by a corrective that came out under the name of Ascanio Condivi, but was evidently coordinated by Michelangelo himself. Finally, in 1568, Vasari produced an emended version of his biography for the vastly expanded second edition of his Lives. This means that from his own day to the present there has been a remarkable degree of consensus concerning the corpus of Michelangelo’s painting, sculpture and architecture. By contrast, his figural drawings remain the victims of extraordinary connoisseurial mood swings (there is broad agreement over his architectural drawings). Around 1900, Bernard Berenson and others took a minimalist view, numbering the total of autograph sheets around 200, and this figure has been slowly but surely climbing since the 1950s, especially in what might be described as the Anglo-American and Italian axis, towards a figure of around 800, counting fronts and backs of double-sided drawings separately. Michelangelo is known to have organised bonfires of drawings, so it is worth underlining that such a total represents a modest average of under 12 surviving drawings for each year of his working life. Yet a persistent strain of German scholarship has resisted this expansion, and perhaps the most charitable thing one can make of this book’s exclusionism (it brings the number back down to 200) is that it is more of the same.

The author of the figural drawings section is Thomas Pöpper, a lecturer in art history at Leipzig, whose entry on his university’s website describes him as an expert on sculpture, not drawings. He explains that “each attribution has been weighed up again and again in a lengthy process of review”, and that “it is not possible to explain how this was done in each case”. In fact, the reasoning behind several hundred individual thumbs down is not once explained, although we are promised “an in-depth discussion of this topic elsewhere”.

For the time being, what the reader is given is a splendidly illustrated all-colour anthology of 240 figural drawings variously categorised as Michelangelo, Michelangelo (partly), Michelangelo (?), Michelangelo (copy?), Michelangelo (workshop), and after Michelangelo. To this is added an extremely useful list of all the generally accepted Michelangelo sheets, together with Pöpper’s ex cathedra verdict on their status.

Turning the pages of reproductions is a surreal experience, as some of the most beautiful drawings ever made are summarily dismissed. It would of course be simpler if the evidence of handwriting, watermarks, provenance and the like could prove a drawing was by Michelangelo or anyone else, but ultimately we must form a view by using our eyes. Every so often (as in the case of the red chalk study in the British Museum for the figure of Adam for the scene of his Creation on the Sistine ceiling) we are afforded the opportunity to compare what I should perhaps not dare describe as the original with a copy in the Louvre (for Pöpper, they are both “after Michelangelo”, a term he usually employs for what he believes to be copies of lost original studies, but here for 16th-century forgeries). These comparisons invariably vindicate the originals, and it is hard to imagine the visual material persuading anyone who does not require the aid of a labrador and a white stick when studying drawings. As it happens, the British Museum is currently displaying both the Adam and an equally sublime drawing for the figure of Haman in red chalk, also for the Sistine ceiling, so sceptics can go and judge for themselves.

In the book’s preface, Frank Zöllner, professor of Renaissance and Modern Art at Leipzig University, states that its radical approach to the drawings “should be understood as a starting point for future discussion”, which sounds like a plea for its inadequacies to be treated leniently. More disquieting by far is his wish that what he dubs “the stagnating debate surrounding the attribution of Michelangelo drawings” should enter “a new phase, one that is dictated neither by the interests of the art market nor by the desire to secure for the artist the most comprehensive possible graphic oeuvre”.

The first part of this implies that auctioneers and art dealers are in the business of selling drawings as Michelangelos which they do not believe to be by him. The second part – more cryptically – seems to suggest that museums and their curators are determined to protect “their” Michelangelos from attack, for comparable reasons. This is poisonous nonsense. I would not dream of proposing that the authors of this volume are acting in bad faith in order to attract a few headlines; sadly, I am sure they are fools, not knaves, and they should accord those who disagree with them the same benefit of the doubt.

An originals sin?

Michelangelo’s preliminary sketch for the Sistine Chapel’s fresco of the creation of man, right, is among the British Museum’s great treasures. Its provenance, however, does not impress the authors of Michelangelo: Complete Works, who dismiss it, and others, in a sentence. “They prove upon closer inspection chiefly to be early copies after the finished fresco . . . occasionally deliberately trying to pass themselves off as original sketches.” The response of the British Museum’s curator of Italian drawings? “I’m all for a fair fight.” Curiously, the book is not stocked by the museum’s shop.

Michelangelo: Complete Works

by Frank Zöllner, Thomas Pöpper and Christof Thoenes (Taschen £120 pp768)

Available at the Sunday Times Books First price of £108 (inc p&p) on 0870 165 8585

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