Knock around the art world long enough and you realize that anything goes and everything is happening simultaneously. If conceptualism is all the rage in avant-garde circles, somewhere artists are beavering away on spin paintings or sculpting cheese curds. The year 1964 was one of those moments when the reigning "ism" -- abstract expressionism -- had sputtered out, and the zeitgeist screamed for change.

Cultural and political upheavals added to the pressure for a breakout. President John F. Kennedy had been killed the previous year. Decades of racial injustice were coming to a boil. In Southeast Asia, the United States started bombing an obscure country called North Vietnam that most Americans couldn't locate on a map.

Even so, life was pretty good. Skirts were short, the music rocked, the moon beckoned, and lots of Americans were optimistic enough to kick back, pop a beer and enjoy life.

Walker Art Center was young, feisty and receptive to the rambunctious newness of the time. Having jettisoned its aspirations to be a pyramids-to-Picasso museum in the late 1940s, the Walker was feeling its oats as a contemporary art center. Among much else, it imported new art from Argentina that year, bought an all-white Italian painting and was given a wall sculpture that included the word "air" in blue neon.

All that is surveyed in a smart new show called "1964" on view through Oct. 24. Organized by Walker curator Siri Engberg, it includes sculpture, paintings, films, videos and even a transparent plastic dress. All the art was made in the 1960s, most of it in or near 1964. Many pieces were acquired then, too, although some were donated or purchased later.

And what an eclectic, fertile moment it was. Pop art is, of course, the signature style of the time, nicely represented by an Andy Warhol image of Marilyn Monroe, the era's exemplar of sex and celebrity. Also by Warhol: a pile of grocery boxes signaling the explosive growth of consumer culture, and 15 prints about the Kennedy assassination, with its gruesome conflation of fame, politics and tragedy. A comic-book style "Explosion" sculpted by Roy Lichtenstein and a huge fabric sculpture of shoestring potatoes by Claes Oldenburg amplify the Pop theme, along with Jasper Johns' painting of two American flags in eye-tricking colors. (Stare at the green-and-orange flag a while, then look at the gray one for a patriotic color shift.)

Pop was merely the populist tip of the era's creative iceberg, however, and Engberg deftly samples pretty much every other trend du jour, including: an eye-dazzling op-art Bridget Riley painting, a neon-light sculpture by Dan Flavin, droll postcards and letters that Ray Johnson sent friends as "mail art," a minimalist red lacquered wall-sculpture by Donald Judd, a plastic rose wrapped in cellophane by Christo, an enormous assemblage recycled by Louise Nevelson from discarded architectural ornamentation, two of George Segal's plaster-cast sculptures, a painting by Italian artist Michelangelo Pistoletto on mirror-polished steel, a torn canvas by Austrian performer Otto Muehl who was intent on killing painting, and an ice-cream glass that Paul Thek filled with disgusting goo as a critique of soda-fountain escapism when war loomed.

There are also Fluxus games and several continuously running films that flood the galleries with a surprisingly compatible soundtrack of bubble-gum rock alternating with Stockhausen noise. A 9-minute video of Yoko Ono's "Cut Piece" proved especially riveting. Staged at Carnegie Hall in March 1965, the performance consisted of Ono kneeling passively onstage while at least 20 members of the audience cut away her clothing. In these post-feminist times, it is deeply disconcerting to see women take the lead in her symbolic despoliation and to hear the tittering and flutters of applause as cutters, male and female, remove her undergarments. Profound political and psychological undercurrents rage, too, in an event staged 20 years after Japan's humiliating defeat in World War II, and almost exactly a year after New Yorker Kitty Genovese was murdered while neighbors allegedly ignored her cries for help.

This art has aged well. A half-century later, it's still aesthetically vital and psychologically relevant. Democratic and visual, it pulls viewers into its ethos and offers a fresh and approachable take on the familiar. Segal's plaster casts of a woman brushing her hair and a man tarring a roof depict working-class stiffs, ordinary Americans living quotidian lives now immortalized in art. Christo's rose and Warhol's groceries are similarly iconic, along with Nevelson's moody castoffs, Fluxus' toys, Flavin's light and even Ed Ruscha's silkscreen of a "Standard" station. For years Walker has boasted about wanting to break down whatever barriers stand between art and audience. "1964 "does it.

Mary Abbe • 612-673-4431