Five hundred years have passed since the death of Leonardo da Vinci at Amboise on 2nd May 1519. His reputation, which has never stood higher, might be summed up in the judgment of one famous critic: he is ranked with Phidias among artists ‘incapable in their way, of any improvement conceivable by human mind’.1 These are the words of John Ruskin, whose birth in London on 8th February 1819 is another major anniversary being celebrated this year, with a programme of exhibitions, conferences and other events scarcely smaller than that devoted to Leonardo, albeit more confined geographically.2

Ruskin’s verdict on Leonardo is usually quoted out of its context in the first volume of Modern Painters, published in 1843. It forms part of an appreciation of J.M.W. Turner, and the reference to Phidias and Leonardo is no more than a nod to a canon of artistic genius. Ruskin began to change his mind when he started looking at Leonardo’s paintings, which necessitated travel since there were as yet none in any public collection in Britain. When in 1844 Ruskin studied the Virgin of the Rocks in the Musée du Louvre he made notes on the species of flowers depicted in it. Although he then admired the painting, Ruskin’s proto-Pre-Raphaelite emphasis on Leonardo’s botanical accuracy contained the seeds of his later disapproval. Returning in 1849 he could find only fault with the painting, condemning its depiction of rocks as being so stylised as to be ‘no better than those on a china plate’.3

By 1865 Ruskin had turned against Leonardo: ‘because he made models of machines, dug canals, built fortifications, and dissipated half his art-power in capricious ingenuities, we have many anecdotes of him;— but no picture of importance on canvas, and only a few withered stains of one upon a wall’.4 This assessment, an exaggerated version of Vasari’s verdict on the artist, seems less surprising than Ruskin’s determination to elevate Bernardino Luini above Leonardo: because Luini ‘laboured in constant and successful simplicity, we have no anecdotes of him;— only hundreds of noble works’.5 It might be thought that Leonardo’s combination of consummate draughtsmanship with intense curiosity about the natural world would have appealed deeply to Ruskin, but his judgment was based on inadequate evidence. In particular, he knew few of Leonardo’s drawings and none of his unpublished writings.

The failure of such a great Victorian critic to understand Leonardo is a reminder of how much our knowledge of the artist is based on developments that began in the late nineteenth century. Most significantly, there was the publication in 1883 of Jean Paul Richter’s Literary Works of Leonardo, which remains the foundation of the study of Leonardo’s manuscripts. Modern appreciation of them is demonstrated by the exhibition that has started the anniversary year, Water as Microscope of Nature at the Galleria degli Uffizi, Florence (to 20th January), based around the loan by Bill Gates of the Codex Leicester.

Richter was the first scholar to study in depth one of the major repositories of Leonardo’s drawings, the Royal Collection at Windsor Castle. Appreciation of them had been hampered by the fact that it was not until the nineteenth century that they began to be removed from the volume into which they had been bound in the late sixteenth century. Representing a large span of the artist’s career and almost the entire range of his interests, the collection unlocks Leonardo’s mind to an unparalleled degree. In February 144 of the drawings will go on show in twelve simultaneous exhibitions across the United Kingdom before coming together as part of an exhibition of 200 drawings at the Queen’s Gallery, Buckingham Palace, Leonardo da Vinci: A Life in Drawing (24th May–13th October).6 The exhibition will be accompanied by a book by Alan Donnithorne, presenting the results of recent scientific analysis of the drawings’ materials and techniques, such as the type of stylus used by Leonardo in his metalpoint sheets and the composition of the pigments in their grounds.

The other major exhibition of the anniversary year will be Leonardo da Vinci at the Louvre (24th October–24th February 2020), which promises to be the most comprehensive exhibition on the artist since Leonardo da Vinci: Painter at the Court of Milan at the National Gallery, London, in 2011– 12.7 It will be very interesting to see the effect of the juxtaposition of the museum’s recently cleaned Virgin and Child with St Anne with unrestored works. Might the exhibition finally trigger the release of Mona Lisa from the deeply discoloured modern varnish in which she is trapped?

The most welcome of the smaller anniversary exhibitions are those that focus in detail on particular aspects of Leonardo’s intellectual world, such as that on his physiognomic studies, at the Teylers Museum in Haarlem (to 6th January). So wide were Leonardo’s interests and so enormous the academic industry that has arisen around them that no one scholar can encompass his achievements. The exception is Carmen C. Bambach, whose monograph on Leonardo – a book that for once merits the cliché ‘long awaited’ – will be published in four volumes by Yale University Press in June. What will it leave for other scholars to do? We must wait to see, but it seems likely that attention will turn in future to Leonardo’s intellectual sources. The popular perception of him as a thinker ahead of his time has helped to obscure his debt to medieval intellectual traditions, in the Islamic world as well as Europe.

Despite the intense study of Leonardo, many paintings and drawings still lurk in an attributional penumbra. Light will only be brought to this academic sfumato by further work on Leonardo’s influence: in other words, how precisely can the ‘Leonardesque’ be defined? That question may seem especially pressing if, as hoped, the Abu Dhabi Salvator Mundi makes an appearance at the Paris exhibition. It can be argued that this noble wreck of a painting has been made by restoration into something ‘Leonardesque’. Those who find it disagreeable – or think that it might be by Luini – may like to recall that in 1865 Ruskin deplored the way that Leonardo ‘remained to the end of his days the slave of an archaic smile’.8 Although he presumably had the Mona Lisa in mind, Ruskin’s criticism was based on a knowledge of the Leonardesque rather than of Leonardo’s own achievements. One hundred and fifty years later there is still some way to go in distentangling what Leonardo did from what he is thought to have achieved.