Back in 1977, I joined the notorious, London-based duo Genesis P. Orridge and Cosey Fanni Tutti in an impromptu performance. Banned in England because of their show "Prostitution" at London's Institute of Contemporary Art, they were touring the artists' spaces circuit in the United States.

While ferrying them to an interview, I got a flat and flopped up to a seedy gas station on Chicago's northwest side. After one look at Tutti's tutu-length skirt and Orridge's long green fingernails, Mongolian knot and powdered face, the attendant asked for autographs, even mine.

Orridge languidly explained in thick Cockney that we were part of the rock group Throbbing Gristle, and had gotten lost on our way to the stadium. As they excitedly waved us on our way, we promised to send them copies of our latest album.

He hadn't pulled the name out of a hat, Orridge explained. He and Tutti were spending all their grant monies on electronic instruments. They were longing to get into rock. (And did, eventually.)

The protean nature of performance art is often overlooked. As described by outraged commentators and congressmen, it appears a very marginal activity indeed, indulged in by kooks for small, insider audiences. Its very status as art has been questioned by no less an expert than Helen Frankenthaler, grande dame of abstract painting and member of the National Council on the Arts.

Even the artists sometimes seem to cling to marginal status. In interviews they often portray themselves as members of a tiny, harassed minority, eking out an existence on the fringes of the visual arts.

Yet by most measures, performance art has been by far the most successful of all the modern arts. It has the widest, most enthusiastic audience and generates the most money. Not even in their dreams could the futurists and dadaists have envisioned the impact of their live performances on the way we live and think. Among the direct descendants of those wild evenings in Turin, Zurich and Paris are Monty Python and music videos.

Performance art as practiced by Madonna, Michael Jackson and 2 Live Crew is rock and rap. When John Cage performs, it's music. When Meredith Monk, Bill Irwin, Laura Dean, Trisha Brown, Lucinda Childs and Pina Bausch do it, it's dance. A Peter Sellars performance is theater; a Robert Rauschenberg performance is art; a Garrison Keillor performance is radio; a Robert Wilson performance is opera. Mainstream media gobble up the innovations of performance art faster than microbes can eat oil.

One might almost say that performance is so central to the evolution of the 20th-century arts that it has become nearly invisible. It only explodes into view when there is a scandal, as recently when the National Endowment for the Arts denied four artists grants because of the content of their work. Yet confrontational content is at the very heart of 20th-century performance. The innovations that nourish modern film, television, theater, dance and music were initially devised by performance artists to challenge the audience.

Performance art is linked to the visual arts by association. The most tangible residue of the futurists and dadaists are art works we sell, buy and put in museums. Their evanescent performances have been turned by art historians into mythic events heightening the value of the art.

It's not really surprising, though, that visual artists had a big hand in bringing the theater and dance up to date. Since ancient times, painters, sculptors and architects have been involved with the design and arrangement of spectacles. Leonardo da Vinci proved a master impresario in the service of the Duke of Mantua. For a 1490 pageant entitled "Paradiso" he dressed his performers like planets and sent them flying through the air with winches. The Baroque sculptor Gian Lorenzo Bernini constructed a realistic flood scene in 1638 for "The Inundation of the Tiber."

These spectacles were staged for the pleasure of the powers that be. Twentieth-century performance was born in the spirit of revolt. Although many present-day performers feel more than a little uncomfortable with the fascist sympathies of their progenitor, there can be no doubt that the futurist poet and prophet Filippo Tommaso Marinetti (1876-1944) invented performance art as we know it today.

He penned the first futurist manifesto in 1909. Some of it might have been written yesterday. "We will sing of the multicolored, polyphonic tides of revolution in the modern capitals," reads one line. Proclaiming the beauty of speed and violence, Marinetti wrote, "A racing car whose hood is adorned by great pipes like serpents of explosive breath -- a roaring car that seems to run on shrapnel is more beautiful than the Victory of Samothrace."

Quickly attracting a group of like-minded collaborators, mostly painters, Marinetti arranged the first full-fledged futurist performance at the Teatro Ciarella in Turin on March 8, 1910. Against a backdrop of brightly colored futurist paintings, he read his manifesto to the accompaniment of clanking noises made by the artists. The furious crowd hurled oranges and rotten potatoes. The evening ended in riot. "There is no beauty except in strife," exulted Marinetti.

The futurist aesthetic developed at astonishing speed. Scarcely an aspect of modern performance was not explored first by these anarchic Italians between 1910 and 1920. Inventing an orchestra of boxes with motors and amplifiers, Russolo wrote a manifesto called "The Art of Noise." (In the mid-'80s a group of British studio musicians and techno-whizzes would take the title as its name.) There were futurist ballets with mechanical movements, futurist dramas in which you saw nothing but the actors' feet. Their performances eventually evolved into a kind of synthetic theater of the absurd in which the acts were brief, inventively mixed different media, involved a lot of things going on at once and aggressively confronted the audience.

In 1913, Marinetti codified these ideas in yet another manifesto that still stands as the most useful key to the nature of 20th-century performance art. Known as "The Variety Theatre Manifesto" and published, among other places, in the London Daily Mail under the title "The Meaning of the Music Hall," it presents Marinetti's argument that the British music hall could provide a "crucible" for dramatic entertainments that embodied modern speed and dynamism.

The Italian poet loved the anarchic nature of the music hall, its circus-like atmosphere, its illogical sequence of acts, its mix of music, dance, theater, spectacle and its outrageous performers popping in and out of character. He liked their nimble delivery, rapid patter and quick changes, their willingness to try new technologies like film, sound recordings and lighting. Most of all he loved the sparks that flew between performers and an audience that cheered, booed, sang along or threw things if they felt like it.

Since he hated "the Solemn, the Sacred, the Serious, the Sublime of Art with a capital A," Marinetti might not have been so keen on operatic extravaganzas like Robert Wilson's "Einstein on the Beach." Nevertheless, Wilson's use of illogical sequences, electronic sets and music, synchronous action and mechanization of movement owe a huge debt to the futurist pioneers. And there can be no doubt that Marinetti would have adored Monty Python. Its irreverence, its crazy changes of scene and costume, its "naughty bits" were right in his line.

Military service in World War I put a temporary halt to Marinetti's high jinks. But his ideas were picked up by a small group of draft evaders in Zurich, where an unemployed German writer and producer named Hugo Ball and his mistress, nightclub entertainer Emmy Hennings, convinced the proprietor of a bar that he could sell more beer and sausages by starting up a literary cabaret.

"Young artists of Zurich are invited to bring along their ideas and contributions," read Ball's 1916 announcement of the Cabaret Voltaire. The very first night, artists Marcel Janco and Jean Arp and Romanian poet Tristan Tzara arrived while Ball was still putting up futurist posters.

After some rather tame evenings of poetry reading and dancing to the tunes of a balalaika orchestra, dada performance art began to take shape. They invented masks, puppets, outlandish costumes. On a typical night, Janco played an invisible violin, Hennings did splits and Tzara wiggled like a belly dancer.

The dadaists wanted to strip art down to its most primitive level before it was "corrupted" by society. Henning used basic movements in her dances; Arp made forms according to chance. Renouncing "language devastated and made impossible by journalism," Ball wrote sound poems with "hiccups ... moos and meowing." The staid Swiss loved the pandemonium. For five months, until the owner got tired of the noise, Cabaret Voltaire was a great success.

From these futurist and dadaist beginnings, performance art proliferated. There was constructivist performance in Russia, surrealist performance in Paris, Bauhaus performance in Dessau and Weimar in Germany. Transplanted to the United States between the two world wars, performance art, like so much European modern art, left behind its politics and concentrated on the development of its forms.

John Cage was a central figure during the 1950s. Convinced by his study of Zen Buddhism that nothing was inherently good, bad or ugly and that art should be continuous with life, he taught his experimental music class at New York's New School for Social Research that chance and nonintentional actions could guide their art. Allan Kaprow, inventor of "Happenings," was one of his students.

A little earlier, in 1952, Cage collaborated with dancer-choreographer Merce Cunningham and artist Robert Rauschenberg in anarchic performances at Black Mountain College. In turn Rauschenberg collaborated with Cunningham's students Trisha Brown, Lucinda Childs and others in a performance piece in which the dancers reacted to the artist's moving collage of props and projected images.

As collaborations and alliances shifted from year to year, the performance ethos and Cage's ideas -- appealing in their experimental, anything-goes philosophy -- spread throughout the New York art, music, dance and theater communities and from there to the rest of the country. Encouraging the use of new forms and new media in these disciplines and experimental collaborations among them, they proved enormously fruitful for American art. For years the National Endowment for the Arts has supported this kind of experimental work handsomely.

For the last two decades, however, innovation in performance art has been spurred by emotional content, often difficult, confrontational content, as with Chris Burden's risk-taking body art or Karen Finley's "The Constant State of Desire," which inserts harrowing ruminations on sex and violence into a cabaret monologue format. Feminist artists have been particularly active in performance circles.

One such performance in the 1970s sorely tested my tolerance. At a crowded opening in Chicago's Artemisia Gallery, three men in black leather charged through the door, seized an artist named Joy Poe and threw her, screaming, to the floor. As one of them went through rather convincing motions of raping her, the other two kept the audience at bay. It was all over in a few minutes; within five Poe was explaining to the thunderstruck crowd that her performance was intended to raise consciousness about the vulnerability of women to attack.

I was deeply offended by the unexpected intrusion of such unmediated violence into a public space. An elderly woman, misunderstanding "art" for life, got hysterical. Luckily my 10-year-old wasn't there, although I was in the habit of taking her to openings. The "Joy Poe Rape Performance" engendered a flood of letters to the New Art Examiner, which I was editing at the time. A few were pro; many were con. To my mind, there was no excuse for not warning guests ahead of time that they would be participating in a theater of cruelty.

But censoring rape as performance subject matter would be absurd. Like cabaret entertainers and stand-up comics, today's performance artists deal with current issues; it is on the front lines of challenging content that they do their best work. Defunding performers because they deal explicitly or imaginatively with the subjects of sex, abortion, AIDS or homosexuality is like declaring life off limits to literature.