Martin Gayford argues that Blake's visions and his homemade philosophy can be a barrier to appreciation of his art.

One of the most vivid documents in the history of British art is a copy of the literary works of Sir Joshua Reynolds. On the title page of the first volume, the original owner made a note in his beautiful handwriting: ‘This man was hired to depress art. This is the opinion of Will Blake my Proofs of this opinion are given in the following notes.’ The marginal annotations on the pages that follow are pungently critical of the text and its august author.

The great poet, painter and engraver William Blake (1757–1827) was, of course, an odd man out in the world of late-Georgian art: an iconoclast and a neglected eccentric. As Alexander Sturgis, Director of the Ashmolean Museum, Oxford, writes, Blake was among ‘the most complex and easily misunderstood’ of artists. Scholars, he goes on, ‘feel they must take proper account of his extravagant religious and social beliefs’ and ‘the palpable reality of his visions’.

The new exhibition at the Ashmolean, ‘William Blake: Apprentice & Master’, takes a different approach, putting the brilliance and novelty of Blake’s work as an engraver/printer/poet in the foreground. After all, Blake was not altogether an outsider. As a youthful artist, he was thoroughly trained. First, he was apprenticed to a prominent engraver, James Basire, after which he studied for six years at the Royal Academy Schools.

As an apprentice, he drew the medieval effigies in Westminster Abbey. He was also well acquainted with the art of the Old Masters, at least through prints (there were no public art galleries open in the London of his youth). One of his first identifiable works was a copy of a figure in the lower left of Michelangelo’s Crucifixion of St Peter. Blake repositioned this brooding giant on the seashore and dubbed him Joseph of Arimathea Among the Rocks of Albion. This is a good example of how Blake’s ‘visions’ were, in many cases as Kenneth Clark pointed out based on vivid visual memory.

The choice of Michelangelo was significant because instinctively and stubbornly Blake preferred the clear outlines of Renaissance drawing to the illusionism of Venetian and Dutch painting: the lying ‘infernal machine’, as he called the chiaroscuro that obs-cured the true form with shadows and blurring brushstrokes. This was the reason for his detestation of Reynolds and all he stood for and why Blake stood apart from the main-stream of 18th-century painting.

The most unusual feature of the installation is a reconstruction of Blake’s studio at 13, Hercules Building, Hercules Road, Lambeth, SE1, where he lived and worked between 1791 and 1800. This house one of London’s most intriguing lost buildings survived until it was demolished in 1918 (despite vehement protests by a writer for The Spectator). At that date, it was still much as it had been when inhabited by Blake. The fig tree and vine he had been given by the painter Romney still grew in the garden.

Atmospheric photographs and measurements of the site made it possible to re-create Blake’s working space in the years in which he made some of his finest illustrated books including The Marriage of Heaven and Hell and Visions of the Daughters of Albion and achieved the most prosperity he ever saw. Those illustrated books, Phillips points out, were an extraordinary innovation. Even more so were the large colour prints, including Newton and Nebuchadnezzar, of 1795.

Normally, the typesetting of the text and the engraving of illustrations were separate operations, undertaken by different craftsmen. Blake found a way of integrating both on one plate, thus cutting out the middle men and becoming writer, illustrator, printer and retailer of his own books (much like a modern self-publisher on the internet).

‘I must create my own system or be enslaved by another man’s.’ Accordingly, he devised his own philosophy and religion and, Clark noted, ‘a pretty good muddle it is’. Fascinating though Blake’s ideas, his imagination and visions can be however muddled they can also be a barrier to the appreciation of his art (his insistence on those visions caused the poet Southey to judge Blake ‘a decided madman’ when they met). This exhibition squarely focuses on his achievement not only as a visionary, but also as a visual artist.

‘William Blake: Apprentice & Master’ is at the Ashmolean Museum, Oxford, from December 4 to March 1, 2015 (01865 278000; www.ashmolean.org)