JIM LEHRER: Now a painter who changed American art. Senior Producer Jeffrey Brown reports.

JEFFREY BROWN: The painting is violent, like a boxing match.

KIRK VARNEDOE, Museum of Modern Art: The way that things are flung against the canvas -- the splat, the splatter -- there's a sense of aggression in the picture.

JEFFREY BROWN: It's lyrical , like a ballet. (music in background)

KIRK VARNEDOE: There's something extremely fine and delicate about a lot of these lines that is choreographed on some level of ecstasy.

JEFFREY BROWN: It's dense, like a dream --.

KIRK VARNEDOE: There's no foreground, there's no background, there's no tree, there's no dog, there's no recognizable anything in this picture. And yet there's a sense of very complex space that's poised between opposites.

JEFFREY BROWN: That is the view from curator Kirk Varnadoe of "Autumn Rhythm," dripped, poured, and flung into existence by Jackson Pollock in 1950, and now part of a Pollock retrospective at New York's Museum of Modern Art. The music is from a CD put out by the museum, the jazz Pollock listened to for days on end, from his own collection.

JACKSON POLLOCK: Sometimes I use a brush but often prefer using a stick. Sometimes I pour the paint straight out of the can.

JEFFREY BROWN: Pollock, shown in this 1951 film, is the man who poured the paint -- "Jack the Dripper" as Time Magazine called him back then. He was at the center of a group, known as abstract expressionists, who changed both the look and the geography of art after World War Two, giving it a distinctly new, American face. But when he died in 1956 in a drunken car wreck, his legacy was uncertain. Pollock's life was marked by both a burning ambition to be a great artist, and real doubt as to what he had achieved.

KIRK VARNEDOE: Pollock's idea of being an artist had a notion in it of making a mark in the world. Pollock had a range of emotional difficulties. He had a dislike of authority. He slugged one instructor in grade school, and slugged another one in high school. He was thrown out of school twice. And the idea of shaping something, of making something, of composing something was almost like a metaphor for him of taking charge of his own life.

JEFFREY BROWN: Pollock was born in Wyoming in 1912. His family moved around the southwest, before settling near Los Angeles. At age 18 he dropped out of high school and moved to New York, where he struggled for more than a decade to make it as an artist.

KIRK VARNEDOE: People who knew him in the early thirties, in his early years as an artist flat out said he could not draw. And you see from his early paintings and drawings that there's something about struggle and push in the work; nothing came easy to him.

JEFFREY BROWN: His early work shows him trying out different styles -- of an early mentor, the regionalist painter Thomas Hart Benton -- of the Mexican muralist painters, and, by 1941, of Picasso and the European avant garde. It was this work that caught the eye of the hottest art dealer of the day, Peggy Guggenheim. She signed Pollock to a contract for a show in 1943 and commissioned a huge mural -- his first large-scale work.

KIRK VARNEDOE: It's a real Paul Bunyan kind of exploit story and you get skeptical just listening to it.

JEFFREY BROWN: The story goes that Pollock secretly tore down walls in his rented Greenwich Village apartment to make room for the 18-foot canvas -- and then, after procrastinating for months, painted the whole thing in one 15-hour marathon session.

KIRK VARNEDOE: When you look at the picture, it's clear that no matter how long it took him to paint this picture, he never thought twice during the whole time he was painting it. There is a family of marks, hooks, commas, scythe-like marks, long loops and sinews that set up a rhythm. And that rhythm runs across the length of the canvas like a kind of stampede. It's clear that he got onto something, it got a hold of him, and he let it rip across the surface of the canvas.

JEFFREY BROWN: Pollock was also letting it rip in the barroom; he was a heavy drinker -- a mean drunk by many accounts -- and often in the midst of fights. But in 1942 he'd met painter Lee Krasner. Three years later they married and she persuaded him to leave the city for East Hampton, Long Island. The exhibition features a re-creation of Pollock's Long Island studio.

KIRK VARNEDOE: Getting Pollock away from the bars in New York in the mid-forties was a key move and allowed him to concentrate. I mean, East Hampton was really isolated in those days. And it concentrated him on his art in a very special way.

JEFFREY BROWN: Now came the radical break -- fully abstract works quite new in their look and their craft. Pollock abandoned traditional painting techniques -- laying his canvases on the floor, for example, -- and even traditional paint - he often used common enamel house paint which he'd pour out or dribble through a small hole in the can, or fling with a stick. Objects such as nails, coins, even a cigarette butt, made their way into the surface of the painting.

JACKSON POLLOCK: And we have mechanical means of representing objects in nature, such as the camera and the photograph. The modern artist is expressing an inner world, expressing the energy, the motion, and other inner forces. The modern artist is working with space and time, and expressing his feelings rather than illustrating.

JEFFREY BROWN: Hans Namuth photographed Pollock in his studio and filmed him in action outside for better light.

JACKSON POLLOCK: I don't work from drawings or colored sketches. My painting is direct. I usually paint on the floor. I enjoy working on a large canvas. I feel more at home, more at ease in a large area. Having the canvas on the floor, I feel nearer, more a part of the painting. This way I can walk around it, work from all four sides, and be in the painting.

KIRK VARNEDOE: You cannot imagine the impact these photographs, as distinct from the paintings, had on artists world-wide when they were first published in the fifties, to see a man making up art like this. To see him standing into his canvas, to see him throwing down paint was so radical that the pictures had a huge impact on the popular imagination of Pollock.

JEFFREY BROWN: Like the paintings, with their large scale and bursting energy, the image of Pollock the artist was recognized as distinctly American. In 1949, Life Magazine made him a celebrity -- a cultural icon of the post-war years.

KIRK VARNEDOE: The cigarette hanging from his lips, crossed leg, crossed arms, staring you down, tough guy, the sense of a kind of blue collar, macho tough guy as an abstract artist changed the whole definition of what the avant garde was in the United States. I think Pollock created an art into which a lot of people projected a lot of anxieties of the post-war era. They felt that this war was savage, violent, apocalyptic in a way that they felt was attuned to the age of the atom bomb, the age of an intense interest in Freudian matters, and psychological matters. At the same time, his confidence, his macho, his very celebrity and success fed the notion of America's emerging from the war as a leader on the global cultural stage.

JEFFREY BROWN: Three large paintings done in a brief period in 1950 now seem to represent the height of Pollock's powers -- one is spare, black and white -- another dense and lush ... the third, "Autumn Rhythm." Yet, along with the growing reputation, there were always those who saw a phony claim to fame. "It's easy to describe a Pollock" wrote an art critic in 1950 -- "chaos -- absolute lack of harmony -- complete lack of structural organization -- total absence of technique."

JEFFREY BROWN: For some people this will always be the quintessential 'my five year old could do it.' I have a five year old. Could he paint this painting?

KIRK VARNEDOE: No. Your five-year-old could absolutely not do this. But if the art didn't push that button, if it didn't push hard against the notion that it was radically unconventional, that it defied any standard notion of skill, it wouldn't be the modern art that it is. It wants to push hard against that. It wants to leave behind all of the comfortable anchors that allow you to judge whether the picture is good or bad, or indeed whether it's legitimately a work of art.

JEFFREY BROWN: Even Pollock had his doubts at times. With some disbelief, his wife, Lee Krasner, quoted him once asking, 'Is this a painting? Is this a painting?' Ruth Kligman, Pollock's girlfriend during a split with Krasner, said he would boast that he was the equal of Picasso and Matisse, and then turn around and say, "I'm no good; I'm a phony."

KIRK VARNEDOE: If you're painting a picture of a dog by a pond, it's going to be a better dog by a pond or a worse dog by a pond. But if you're painting these things, it's either going to be a painting or it's going to be a mess. And it's not guaranteed to pay off, and it's not guaranteed that everybody wants to follow him out to that edge.

JEFFREY BROWN: Pollock himself went over that edge. His focus seemed to drift away. There was more drinking, less work, finally almost no painting at all in his last two years. In August, 1956, driving drunk, he crashed his car into a tree and died. He was 44 years old. Despite all the doubts, his influence grew. After Pollock, artists could not face a canvas in the same way. As for the public, as Kirk Varnadoe says, Pollock challenges by taking attitudes about art and pushing them to the edge. That leaves each viewer to decide whether or not to push back.

JIM LEHRER: The Pollock exhibition will be at New York's Museum of Modern Art until February 2nd. It then moves to the Tate Gallery in London.