THE WIZARD OF AIX

The Cezanne show now at the Grand Palais in Paris is one of the great exhibitions of our age. It comes to London in February

WE ARE fortunate to live in an age of great exhibitions, and the Cezanne retrospective at the Grand Palais in Paris is one of the most moving tributes to an artist that the late 20th century has devised. Appropriately, its power and scope remind one of the huge shows of Picasso and Matisse we saw in New York in 1980 and 1992. These later artists - each of them, in their separate ways, monsters of egotism - correctly thought themselves to be Cezanne's children, and at the Grand Palais one senses the reasons for their reverence.

What is the attitude of today's artists? When the exhibition comes to the Tate in February the IoS will be asking distinguished contemporaries for their reactions. I've never met a serious artist who doesn't admire Cezanne. But that doesn't mean that they feel any affiliation. Cezanne was certainly a father of modern art but he belongs to the French modernism that more or less expired at the time of World War Two. Furthermore, his painting was heir to a classic trad-ition. The comparisons with Poussin are not unjustified.

Indeed, he may have had more in common with Baroque and Romantic painters than with the Impressionists of his own day. He grew up in a time of revolutionary art but was not a revolutionary by nature. He neither felt the great social events of the period nor the social niceties that delighted the Parisian Impressionists. Though born (in 1839) to wealth, his character had much in common with the peasants he so sympathetically portrayed. He kept to his native fields. He was stoical, a constant labourer and sus-picious to the point of paranoia.

By extraordinary coincidence, his schoolboy comrade in their native Aix- en-Provence in the 1850s was Emile Zola. Thus Cezanne became a model for the protagonist of Zola's L'Oeuvre, published in 1886. Note, though, that literature and art did not march hand in hand. Zola knew Cezanne well but did not understand his painting. All through his friend's early period he wrote about the Impressionists, and in fact became their champion. But not once did he mention Cezanne. The painter was already an outsider. In the suave company of artists in Paris he deliberately made himself difficult, coarse as soil. "I do not shake your hand, M Manet. I have not washed for a week." His uncouth manners disguised high and indeed noble ambitions - but this disguise was a good one. For many, his art was as unpleasant as his personality.

We had the opportunity to come to terms with Cezanne's early style in the Royal Academy exhibition of 1988. These paintings still look shocking. They are in their own way as dissonant as the "primitive" paintings of Picasso's African manner around 1907. The canvases are anti-avant-garde as well as anti-academic. It looks as though Cezanne was set on making art without reference to any cultivated standards. He summoned paintings exclusively from his own resources. How violent and primitive they appear. Yet it is worth searching them for beauty. Early pictures include religious scenes, a rape, murder and so on, always depicted in unnatural light. The touch is important because so much of it was done without a brush. Cezanne came to use a palette knife through study of his admired Courbet, but took the technique to an extreme. Many pictures are entirely executed with a knife. In all of them the slicing and plastering of pigment is especially marked. No doubt this was another part of Cezanne's campaign against good taste; but I add that the palette knife is the most sculptural tool in a painter's equipment, and that this had an effect on his later work.

CEZANNE caught up with open-air Impressionism when he painted alongside Camille Pissarro, a wise artist who could often act as a catalyst for other people's innovations. Then for some years in the 1870s he travelled between Aix and the countryside north of Paris. There in the Ile de France, at Auvers and Pissarro's village of Tontoise, Cezanne first made paintings that are unequivocally the work of a master and are also a recognisable part of the modern movement. This period is a little understated in the Paris show but it does have La Maison du Pendu, which was in the first Impressionist Exhibition in 1874, and the Vue d'Auvers, a serene canvas - when seen from a little distance - whose complications become apparent on closer acquaintance.

With his long and awkward apprenticeship at an end we might say that the landscapes of the 1870s represent the classical side of Cezanne's art. The Baroque part of his nature was not lost to view, however. It's there in a renewed series of figure pictures. Une Moderne Olympia obviously responds to Manet. But we now find paintings, primarily the Trois Baigneuses, then the Apres-midi a Naples and the Tentation de Saint-Antoine, that dig deep into the culture of French painting. Cezanne was excavating previous art, quarrying past Courbet and Delacroix - that most Baroque of the Romantics - toward the turbulent, non-classical side of the 17th century.

Though these paintings have erotic themes, their subjects or actors are not observed. Cezanne took the nude as a theme for more than 40 years yet hardly ever painted from the nude model. In his maturity he always insisted on looking at the motif. His clothed models sometimes sat a hundred times before he achieved their portraits. So why not unclothed models? Perhaps he thought that a naked woman in the studio would be too reminiscent of the working methods of academic artists. His much younger friend Emile Bernard once asked him about models, got an evasive reply and surmised that Cezanne suffered from religious scruples. This does not seem very likely. A deeper reason for his restraint may be that Cezanne conceived the nude not as a living person but as sculpture.

I think there was a sculptor within Cezanne's personality, though it is impossible to say whether he would have been a modeller or a carver. In other words, one cannot tell whether his instinct would have been to build up around an armature or to pare down from a block. The former is a wet process, the latter a dry one. And here is a clue to the famous "constructive brushstroke" that Cezanne developed in the 1870s. His handling treats space as though air itself were palpable, with a reminiscence of the palette knife's trowelling and smoothing. And while his brush, in many pictures, has clearly been immersed in plentiful, fat pigment, yet its strokes appear as crisp and thoughtful actions. Never did he caress a shape.

These brushstrokes, often marks in parallel, make us notice their own nature as much as the objects they depict. Though Cezanne never lost sight of the world his touch became an end in itself. Thus he announced later modern art, even abstraction. We used to think he was an orthodox part of art history. I am persuaded of his unorthodoxy by this demanding exhibition. Picasso and Braque's Cubism, developed half a dozen years after Cezanne's death, took all sorts of hints from his painting. Yet Cezanne himself remains awkward, a bit outside history, his own modern artist and his own academy.

He was self-academic, we might say. Rules were of his own making but still they were rules. Look, for instance, at his colour. Cezanne is said to have been a great colourist. So he was, but not in the sense that he presented colour for its own sake. The Midi might have heatened his palette. Or he might have developed the lurid optical sense of his early years. Instead he settled on a range of colour that had wide but not vast limits. He used orange, green, blue and red. There are of course other colours, in particular brown. This is none the less Cezanne's basic palette and his greatness as a colourist is in the accuracy, not the abundance, with which he employed his tints and hues.

There must have been a fastidious selection of colour for each and every application of the brush. Such mental effort separates Cezanne from contemporary artists who painted by instinct or with a less intellectual use of their eyesight - Renoir, for example. My impression is that landscape presented harder tasks for Cezanne than did portraiture. For many artists it would have been the other way round. Cezanne's portraits feel more relaxed than his work before the vistas of Provence, however many hours he spent on the features of people who were near to him - primarily his wife and then himself. At the Grand Palais there are little groups of these portraits, and they give the visitor a little breathing space, a distraction from the strictness of the artist's vision.

Not much is known of Cezanne's wife, except that she was Hortense Piquet, an artists' model. She was 19 years old when Cezanne met her in Paris in 1869. It seems that she cured him, partly at least, of the neurotic fear of women that was a theme of his first decade as an artist. Their child, Paul, whom Cezanne loved with fierce and protective passion, was born in 1872. For many years Cezanne concealed the existence of this family from his conservative banker father. He and Hortense lived apart for long periods. They were eventually married, at Aix, in 1886. Hortense much preferred Paris to Provence, but Cezanne made her live close to him - though not necessarily with him. After 1891 he continued to have his home at the ancestral Jas de Bouffon with his mother and elder sister while Hortense and Paul were lodged nearby - not too close nearby.

Hardly a promising set of arrangements for intimate family portraits. Yet Hortense could well have found it convenient not to live with an obsessed painter, and she posed for Cezanne with great patience and dignity. Conceivably, Cezanne was better able to cope with his wife when he was merely looking at her and her canvas, silently, hour after hour. At all events, portraits of his wife are like deep pools of pure visual emotion. Since they belong to such a secluded part of his life they are not easy to date. It is also difficult to decide which of them are the more profound. Many visitors to the exhibition will prefer to linger over Madame Cezanne aux Chevaux Denoues, which probably belongs to the 1890s. With her hair down for once, Hortense looks less formal than in some portraits. The picture is none the less of monumental gravity and sadness.

In his self-portraits, which (significantly) are never quite full-face, Cezanne appears shrewd and wise. Apart from one anomalous picture painted from a photograph when he was scarcely out of his teens, he did not portray himself until his art reached its maturity. Wise he certainly was, however crabbed his human relations; and the wisdom of his eyesight becomes the more apparent when we study his watercolours and drawings. At the Grand Palais they are housed in a room at the bottom of a flight of stairs, reached after one has looked at very many paintings before about 1890. This gallery is cramped, but it's filled with treasures and reveals something we might not have expected after the physicality of the paintings: Cezanne as a master of watercolour.

One of the best watercolourists that ever lived, I would say, though it is not easy to make comparisons. All Cezanne's art is about meditation, but his watercolours concern what we might call serial meditation. Their loveliness is as surely from the heavens as the oil paintings have their sturdy position on Cezanne's native ground. Alas, many of their colours have faded. A further difficulty is that the whiteness of the sheets on which Cezanne made his marks has often discoloured. Over the years, brownness has crept in, and the original whiteness matters enormously because Cezanne used it not as a neutral ground but as a colour in its own right.

We could almost add the bareness of white to the list of colours in Cezanne's palette. In one respect the watercolour sheets and the painted canvases came to have a common attribute. They are not fully worked from edge to edge. There are expanses of some paintings that are quite without pigment and many passages in which the paint has been applied with different degrees of finish. The "unfinishedness" of so many of Cezanne's paintings invites a range of theories. Obviously one could not ignore the conventions of academic finish before the birth of modern art. Then there was the new notion that an artist's authentic feelings absolved him from the usual regulations. And, as we know, Cezanne made his own rules. It is worth repeating what an aesthete he was. Sometimes his work is unfinished because just one further dab would have made it ponderous or unbalanced. Furthermore, "unfinishedness" emphasised the miraculous and fragile nature of creation. I think that the empty areas have something to do with Cezanne's sculptural yearnings. They reveal his desire for construction. Behind all these theories must lie one personal truth. Cezanne was tentative because he was always in search of some ultimate and infinite expression.

His narrow-mindedness, even his personal failings, all served him in the pursuit of infinity. Two series of late paintings are his testimony as a painter who believed that the sublime and the ineffable might be brought within his grasp. The first are the views of Mont Sainte-Victoire, the second the Grandes Baigneuses. In 1902 he moved into a purpose-built studio in the hills outside Aix. It gave him an especial view of the dramatic Provencal mountain and, just as important, the plain below its slopes. Over and again he recorded this view. In many paintings of this sort he achieved a density and concentration unequalled in previous landscape art. He was able to come to this conclusion through an individual route. The Mont Sainte-Victoire paintings not only draw on his experience as a landscapist. They are also the result of his long and painstaking devotion to still-life. Cezanne's apples, we now see, helped him to paint the ungraspable skies.

Another aspect of the Mont Sainte-Victoire pictures is that they are architectural. We sense some great open-air palace. Also architectural is Cezanne's Grandes Baigneuses of 1906, the year of his death, generally regarded as his most ambitious painting. There are three late Grandes Baigneuses. We know the first of them well, for it is in the National Gallery. A second version belongs to the Barnes Collection. This third and largest one, from the Philadelphia Museum of Art, is so awe-inspiring that it makes the National Gallery picture look like a failure. Henry Moore (a sensitive critic of art) saw it in 1921 when it was still in a Paris private collection. He wrote that it was "like seeing Chartres Cathedral". I suppose that is just. But the immense arches of this painting seem modern too, joining the 20th century to a far older age in a way that only the 20th century could achieve.

! Grand Palais, Paris (00 331 44 13 17 30) to 7 Jan 1996; then Tate Gallery, SW1 (0171 887 8000) 8 Feb to 28 Apr.