Side by side

In 1907, Matisse and Picasso exchanged works, a gesture of mutual admiration between two fierce rivals.

o rate great artists in the way that you might rate, say, Formula One drivers isn't usually a great idea. In fact, it's a ridiculous idea – especially when you are talking about two artists of the calibre of Matisse and Picasso. Between them, these two men produced the first important breakthroughs of the 20th century. Their astonishing creative fecundity lasted, in both cases, for more than 50 years. And they lent modern art not only an aura of high seriousness but a playfulness and love of risk-taking that betokened two imaginations working at full throttle.

So why is it that, of the two, Picasso has, for the longest time, been considered the greater, the more broadly accomplished, the more creatively potent? The Museum of Modern Art's John Elderfield, one of six curators who have worked on the upcoming "Matisse Picasso" exhibition, says that the show "makes no argument about one being greater than the other. But it does, I suppose, make an argument about the difficulty or perniciousness of making judgements like this."

Any such argument has, however, been ignored by those pundits who are using the exhibition as a pretext to indulge in that favourite old game of pick-the-winner. Most, predictably, have gone on record expressing a preference for Picasso. One utterly desperate critic has even gone so far as to anchor his article in the baseless surmise that, had Matisse been alive in France today, he would have voted for Le Pen (the writer in question naturally makes no mention of the fact that Picasso was an apologist for Stalin, and that he continued as such even after he learnt of Stalin's infamous show trials in Moscow).

Picasso's name has been used to sell everything from perfume to cars. Matisse is used, rather less adventurously, to sell a line of paints. Picasso's "superiority" is reflected in everything from exhibition attendance figures to the sheer volume of scholarly research devoted to him. Most tellingly, perhaps, prices for Picasso's works – even works from "weaker" periods such as the early Blue period – consistently outstrip Matisse's at the auction sales.

It wasn't always the case. Matisse was undoubtedly the first in the race to invent a fresh pictorial language for the new century. He was 12 years older than Picasso when his "Fauve" works made their shocking debut at the Salon d'Automne in 1905. Picasso felt the ensuing attention that Matisse received was a serious threat to his own ambitions. A series of radical new Matisse works over successive Salons – Luxe, Calme et Volupté, Le Bonheur de Vivre, The Blue Nude and so on – only drove home the point.

Matisse was not only the first to explore the possibilities of African tribal art, he was also the first to get to grips with and digest the formidable precedent of Cézanne. As Hilary Spurling, author of The Unknown Matisse, writes: "The worrying thing about Matisse at this point was not so much his age, or his air of respectability, as the fact that even the most iconoclastic youth could not make head or tail of his fearsomely subversive paintings."

But of course, everything changed with the invention by Picasso and Braque of Cubism. Matisse's reputation ended up suffering from his lack of interest in movements and the intellectual conformity they entailed. His Fauve colleagues, Braque and Derain, had by now defected to the Picasso camp. "A difficult watershed for me was the period of Cubism's triumph," he later admitted. "I was virtually alone in not participating in the others' experiment – Cubism – in not joining the direction that was acquiring more and more followers and whose prestige was becoming increasingly widespread ... I was entrenched in my pursuits: experimentation, liberalisation, colour, problems of colour-as-energy, of colour-as-light."

There can be no doubt that a natural rivalry existed between both men over a long period. It was in full, tropical bloom during certain phases of their careers and it lay almost entirely fallow during others. It was a rivalry which allowed enough room for admiration and generosity as well as snide asides and furious threats. The two artists frequently visited each other's studios and even exchanged works – the first time in 1907, when Picasso chose Matisse's child-like portrait of his daughter, Marguerite, and Matisse chose a Picasso still life, both of which are in the Tate exhibition. What is most remarkable is the extent to which both men resisted the cruder manifestations of their rivalry in order to pursue their own perfectly idiosyncratic visions.

Still, over time, the phenomenon which places Picasso always ahead of Matisse, as if they continued to be in permanent competition even after their deaths, has resulted in a hollowing out of meanings in both artists' work. John Golding, one of the two London-based curators of "Matisse Picasso", seems tacitly to acknowledge this situation when he tells me: "In terms of their stature, if we haven't brought them out neck and neck, the exhibition is a failure." The clichés that have formed around both men's reputations have, like all clichés, some foundation in truth. But they are so over-developed and entrenched that they tend to short-circuit people's private responses to the actual work.

Picasso's slipperiness, his shocking and often intoxicating unpredictability, has played an enormous part in keeping alive the public's fascination with him. His contradictions which, artistically, were f part and parcel of his greatness, have always demanded a lion's share of attention. They take a greater effort to resolve. Artistically advanced, he could be emotionally adolescent. Politically and socially idealistic, he was in fact atrociously naive in matters of politics. A great and sympathetic lover of women, he was capable of stunning neglect and cruelty ... and so on.

Matisse, although wracked by his own contradictions, was, as an artist and as a man, more of a piece. He, too, had his character flaws: his obsession with the prerogatives of his life as an artist resulted in an alienating self-absorption. At times he seemed surrounded by an aura of humourlessness; and he, too, was "guilty", if that is how we must put it, of various infidelities. But on the whole, his artistic concerns and his personal demeanour have a seamless quality which demands less by way of explanation.

The spread and expansion of Picasso's reputation was hugely aided by the close friendships he formed with some of the most influential writers and critics of his time. "No artist," wrote Leo Steinberg, "was ever more closely surrounded by master wordsmen." The daunting list includes Guillaume Apollinaire, Max Jacob, Gertrude Stein, Andre Salmon, Jean Cocteau, Andre Breton, Paul Eluard, Louis Aragon, Pierre Reverdy and Rene Char. Both as an artist and as a man, Picasso seemed to many of these peers – as he can still seem to us – genuinely engaged with his century, with its moods, its major events. His work seemed to capture the zeitgeist of the terrible, ecstatic era.

As his career progressed, Picasso found himself at the forefront of various cultural and political waves. With Cubism, he and Georges Braque made art out of everyday life and mass culture (still a brand-new phenomenon at that time). In the Twenties, Picasso was a central figure in Surrealism. He was an active supporter of the Republican side in the Spanish Civil War, and, in 1944, he joined the French Communist Party. In paintings such as Guernica and Massacre in Korea, he responded explicitly to war – and he did so from a partisan and passionate point of view. All this took the edge off whatever esoteric connotations Picasso's art (and modern art in general) had in people's minds. It helped his small but quickly growing public to relate to him.

But it was Picasso's personality that was and has remained his greatest asset. From the beginning, there was something exotic and untamed about him. His Spanish upbringing played a huge and ongoing part here. It did more than simply fuel the persistent sense he had of himself as an outsider: it imbued him with a set of responses, habits and values that never really left him, and which others found fascinating, even when they were appalled.

In recent years, Picasso's reputation has been further bolstered by the extraordinary surge of interest in his life. Prior to publishing the first volume of his great biography, John Richardson stated that biographical facts "have more bearing on Picasso's art than is the case with any other great artist, except perhaps Van Gogh ... In no other great artist are the minutiae of gossip so potentially significant." He was right. But it is also true that Picasso himself fell dangerously in thrall to the romance of the idea that his life was indistinguishable from his art. He felt the constraints of the notion, its fertile paradoxes and, at times, its fraudulence more acutely than anyone.

The recent "over-revving" of the biographical approach to Picasso's work has had a sterilising effect on the untouchable, dream-like nature of his most wonderful inventions. Confusion and false consciousness have tended to grow, as it becomes increasingly difficult to tell whether the life is important because the art is great or the art is great because the life is chock full of incident and gossip – material which, in one form or another, made it into the art. Commentators and the public tend to prostrate themselves before the barrage of coded messages in Picasso's work and to indulge in endless guesswork about the comparative personalities of his wives and lovers, their respective standing in his favour, their fates, and so on.

Matisse's reticence, the strange objectivity about his most marvellous creations, stands in stark contrast to all this. He wrote in the text that went with his book Jazz: "An artist must never be a prisoner even of himself, a prisoner of style, a prisoner of reputation, a prisoner of good fortune. Did not the Goncourt brothers tell us that Japanese artists of the great period changed their names several times in their lifetime? This pleases me: they wanted to safeguard their liberties."

But this attitude does not mesh easily with our contemporary culture's preoccupation with biography, with the kind of "personal expression" that is often so difficult to dissociate from narcissism. The other abiding obsession of our culture, of course, is politics, and it has always stuck in the craw of social idealists that Matisse's art never sought to express any political response to the upheavals and atrocities he lived through. Picasso, on the other hand, backed up paintings like Guernica and Massacre in Korea with inflammatory statements such as: "I am proud to say that I have never looked upon painting as an art intended for mere pleasure and amusement ... [It] is a means of waging offensive and defensive war against the enemy." This, of course, was in pointed response to Matisse's 1908 statement that he wanted his art to be like a comfortable armchair for the "tired brain worker" – still the first statement that comes to mind when most people think of Matisse.

People forget, however, that Matisse's Arcadian and transcendent visions were grounded to some extent in the anarchist milieu of his early mentor, Paul Signac, and that his later disavowal of political postures in his art were an indicator of great integrity. "I can't admire enough," wrote Clement Greenberg, "the kind of courage that permitted [Matisse] to write for publication, back in 1908, that he dreamt of an art that would be like an easy-chair for the tired 'brain-worker' ... That Matisse's art actually does ever so much more than that, including 'uplifting', isn't to the point here. What is, is that he himself was willing to claim only so much and not more for it. And maybe those who might want to bestow their own rhetoric on his art were being warned off. His art would speak for itself – just as all art does when it comes down to it, good and bad art alike ..."

Matisse's was an art of accumulated and distilled sensations. Picasso's art, on the other hand, could be seen as a "sum of destructions" (his own phrase). His rapid-fire, myriad transformations, as David Sylvester wrote, "are like those in the pattern seen in a kaleidoscope, forever forming and re-forming as it is shaken up, but only changing, never growing, whereas transformations in Matisse belong to a process of growth."

Picasso certainly came to satisfy, as Meyer Schapiro wrote, "a new norm of creativeness as a process of perpetual innovation, not only from canvas to canvas, but within each canvas". But, for all the admiration he incites, his work can often create a strange sense of disappointment, as the reality of individual works fails to match the extraordinary hype, the great and fascinating myth of the man. One of the pleasures of looking at Matisse has to do with an absence of such clamour in the background.

'Matisse Picasso' runs 11 May to 18 August at Tate Modern, Bankside, London SE1 (020-7887 8000). 'Side by Side: Picasso v Matisse' by Sebastian Smee, is published by Duffy and Snellgrove, ISBN 1 876631 325, AU$22.00.