When David Hockney pronounced "all the works here were made by himself, personally" of his new exhibition of landscapes at the Royal Academy, he wasn't only taunting Damien Hirst and his younger rivals. He was laying claim to a whole tradition of British and Western art and declaring he had made it his own.
It's work of breathtaking ambition and, indeed, of scale. Go into the first, octagonal room and you are surrounded a series of monumental pictures of trees. Each has been painted on eight separate canvases and then joined and each portrays the leaves and light at different seasons. Look through the open door on your right and the space is dominated by an even more gigantic oil of "Monument Valley", a fierce study of red and massed form. Peer through the archway straight ahead and you are startled by a richer, denser oil panting of "Woldgate Woods" while to the left is his brilliant 32-canvas "The Arrival of Spring in Woldgate, East Yorkshire in 2011 (twenty-eleven)".
There has been too much hype about this synoptic show of Hockney's recent devotion to the landscape of his native East Yorkshire and too little. It doesn't represent a total revolution in landscape painting. But it does reveal a major artist at full pelt and bursting with creativity in his seventies. Just as last year ended on the high of the Leonardo da Vinci show of paintings, still running at the National Gallery, so the Royal Academy has kicked off this year with an absolutely stunning exhibition, this time of contemporary art, the paint still fresh on the canvas, reeking of turpentine and oil.
That is not to put the two artists in the same category, although Hockney arrives at this show with the popular reputation of being Britain's greatest living artist now that Lucian Freud and Richard Hamilton have both died. But any good artist, like any good composer, pits himself against the past and attempts not just to extend tradition but to recreate it. In Hockney's case it is the tradition of landscape that he has now set out to build anew.
His decision to live in Yorkshire late in the last decade after four decades in California marks not only his return to his native land but a return to painting and to watercolour, a medium he has tended to leave aside in his career.
The Royal Academy, which commissioned the exhibition from the artist when they first became fully aware of his landscape work in Yorkshire after he produced his 50-canvas "Bigger Trees near Warter" in 2007, have done him proud, giving the artist full space to sow his works, big and small, in profusion but also uncluttered and airy. Hockney's obsession, like Gerhard Richter's, has always been in trying to test what an artist can do which photography alone cannot. It started with using photographs themselves to build up collages of the Grand Canyon in which the photos each portray a slightly different but melding view of the Canyon, acting as the eye does but the photography can't in taking in several viewpoints and several images at once. Always a quick and fluent graphic artist, Hockney went further, and seized the possibilities of drawing on an iPad to produce sketches which could then be translated into print, adjusting for size and tone as he went, an interest he has kept up in his latest digital prints from iPad sketches and in his more recent development of multi-screen film.
With these Yorkshire works, he has applied the same techniques to painting, and tried to give brushwork the same scale as digitally enlarged prints. What close observation of the countryside around has also done is to give him a profound interest in season and light, in portraying the same scenes time and again in different periods of the day and year.
With considerable effect, the Royal Academy has grouped the bulk of his paintings into a series of locational themes in a sequence of galleries that embrace you with a place while delighting you with seasonal variation. It's an organisation that helps you feel the sheer intensity of Hockney's concentration, if it also shows considerable variation in quality. At his best, in works such as the "Felled Trees" paintings of lines of logs arranged along the woodland path, he can take your breath away. At other times, as in some of the "Hawthorn Blossom" paintings you just feel that, in his love of shape, he has simply failed to understand texture.
That is a weakness of Hockney when it comes to landscape. His primary interest is in image and how you project it. Even in representing light, he tends to look on it as a means of clarifying image rather than the subtleties of its effect, as in Monet (whom he much admires) or in the light itself, as in Claude Lorrain. If you compare this show with the watercolour landscapes by Edward Burra on show in Chichester and Graham Sutherland in Oxford, you sense a different objective. In the case of Burra you're witnessing an artist's view of time and himself as he looks at landscape and in Sutherland's case you are experiencing a man's passionate relationship with the land. It's hard to sense either with Hockney. It may be that he does feel a deep spiritual bond with Yorkshire and that his concern with painting and landscape in recent years is a product of his view of his ageing. But it doesn't show in these works.
What does come out of them is an artist at the peak of his powers grasping full on a challenge: the challenge set out in a gallery devoted to his recent painting after Claude Lorrain's seminal "Sermon on the Mount". How does a painter take his observation of nature and make it come alive through the artistry of his hand? It's a task he has embraced with gusto and, one suspects, has still not seen it to its end.
David Hockney RA: A Bigger Picture, Royal Academy, London W1 (020 7300 8000) 21 January to 9 April