Modernism in the arts is 100 years old, because Pablo Picasso's painting Les Demoiselles d'Avignon is now 100 years old. In 1907, the Titanic had yet to sink, cinema was a flickering newsreel of the Boer war, Scott of the Antarctic was still alive and the Wright brothers travelled to Europe to publicise their invention of powered flight. San Francisco was still shattered by the previous year's earthquake. But in a crowded, dilapidated warren of artists' and writers' studios on the Parisian hill of Montmartre, home to anarchy and cabaret, a 25-year-old Spanish immigrant was creating the first, and greatest, masterpiece of modern art.
Picasso drew his first designs for what became Les Demoiselles d'Avignon in the winter of 1906-07. He developed his ideas intensively, in a programme of conscious planning that resembled the great academic projects of Leonardo or Géricault, before finally painting his 8ft square canvas in the early summer. With that painting, the nature of reality was altered as profoundly as it would be by the physics of Picasso's contemporary, Albert Einstein.
This is one centenary worth thinking about. It's not just 100 years in the life of a painting, but 100 years of modernism. Les Demoiselles d'Avignon is the rift, the break that divides past and future. Culturally, the 20th century began in 1907. Consider the dates of other works of high modernism. In music, Schoenberg's Erwartung was composed in 1909 and Stravinsky began The Rite of Spring in 1910. James Joyce didn't get started on Ulysses until 1914, by which time Picasso was into the final stages of cubism.
You can make a case for many beginnings of modern art. Some would say it began with Manet's confrontational 1863 nude, Olympia. After Olympia, the late 19th century and early 1900s teem with provocative works of art that engage specifically with the same sexual territory as Picasso: Munch's Madonna, Klimt's Pallas Athene, Zola's novels. In this context, you could argue that Les Demoiselles d'Avignon is in fact a backwards-looking, unoriginal work of art, a recycling of the 19th century's biggest cliches - "loose women" cavorting in exotic interiors. So what is so new, so radical about this painting?
Five pink women are entangled in silver and blue draperies. Two of them stand with arms raised to flaunt their breasts, staring at you out of huge black eyes. The other three are masked: one in a fleshy brown wooden simulacrum of a face as she stands in profile at the left of the picture; the two at the right in African masks, one of them intruding from behind the jagged cloth while the other squats among fabric diamonds. On a plate, there is a collection of blatantly meaningful fruit: a scything blade of melon with testicular grapes, an apple and a pear. This is a painting of nudes in which there is scarcely a curve to be seen - elbows sharp as knives, hips and waists geometrical silhouettes, triangle breasts.
The painting is square to the eye (in reality there are a few centimetres more to its height than its width), which disposes you to attend to space and symmetry. Or rather, the squareness puts you on your mettle, to look at this perpetual motion machine that never loses its vitality.
Picasso worked on Les Demoiselles d'Avignon as he had never worked on any painting before. One art historian has even claimed that the hundreds of paintings and drawings produced during its six-month gestation constitute "a quantity of preparatory work unique not only in Picasso's career, but without parallel, for a single picture, in the entire history of art". Certainly, it matches the work artists had traditionally put into history paintings and frescoes. Picasso knew he was doing something important, even revolutionary - but what?
He started out with the idea of a brothel scene. The painting was to have a male customer in it, a sailor, or the artist himself. It would have been a shocking slice of contemporary Parisian life, not that far removed from Toulouse-Lautrec or all the other cynically honest "painters of modern life". But you don't think about any of this, or make any of those connections, when you stand in front of Les Demoiselles d'Avignon in New York's Museum of Modern Art.
This is true even in reproduction. Try an experiment. Look directly at Les Demoiselles d'Avignon and speculate on its meaning. You can't. You never get as far as deciding it is a painting of five women, let alone concluding that they're prostitutes, or that it reflects male fears, or reach for any of the neat ways we customarily turn images into words. In order to interpret it, you must look away, or unfocus your eyes. Actually looking at the picture means moving constantly from one facet to another; it never lets you settle on one resolved perception.
Most of all, this is a painting about looking. Picasso looks back at you in the central figure, whose bold gaze out of huge asymmetrical eyes has the authority of a self-portrait. It's interesting that we're trained to see transvestite self-portraits in the art of Leonardo or Marcel Duchamp, but it doesn't often occur to us to understand this painting in that way, misled as we are by the caricatures of Picasso as a patriarchal voyeur. What he painted in 1907 is a work of art that looks back at you with furious contempt.
What struck Picasso about African masks was the most obvious thing: that they disguise you, turn you into something else - an animal, a demon, a god. Modernism is an art that wears a mask. It does not say what it means; it is not a window but a wall. Picasso picked his subject matter precisely because it was a cliche: he wanted to show that originality in art does not lie in narrative, or morality, but in formal invention. This is why it's misguided to see Les Demoiselles d'Avignon as a painting "about" brothels, prostitutes or colonialism. The great, lamentable tragedy of 18th- and 19th-century art, compared with the brilliance of a Michelangelo, had been to lose sight of the act of creation. That's what Picasso blasts away. Modernism in the arts meant exactly this victory of form over content.
That doesn't mean it is disconnected from the world. Les Demoiselles d'Avignon could not be more earthily, pungently affective - it is, after all, full of sex. It's a sexuality that bears no resemblance to that of, say, Klimt. Although it emerges from the same decadent milieu, it does things no artist of the fin-de-siècle had contemplated. In this painting Picasso anticipates the discoveries he made explicit in his cubist pictures: he all but obliterates the 500-year-old western tradition of perspective by flattening his flesh silhouettes in a space that goes nowhere. It's this visual violence that liberates his eroticism, because it erases any meaning or narrative. Such a tremendous unbinding of desire was unprecedented in art, not to mention Christian culture. After the first world war, André Breton came to Picasso's studio, saw Les Demoiselles d'Avignon and recognised it as the definitive modern masterpiece. Breton, the leader of the surrealists, saw in it a painting about the revolutionary menace of the unconscious, and he was right.
Even in a world that no longer worships painting, this painting is unsurpassed. It anticipates the end of painting, gladly contemplates the cultural destructions Picasso was to step back from. There's something anarchist and ruthless about it that contains dada and Marcel Duchamp and punk.
So - a centenary. If you care about modern art, this is its centenary. Works of art settle down eventually, become respectable. But, 100 years on, Picasso's is still so new, so troubling, it would be an insult to call it a masterpiece.
