Alexander Calder was an artist beloved for mobiles that are guided by the wind and other elements of chance.
Composer George Lewis has paid homage to him through a work he'll present in concert Saturday at Walker Art Center.
The musicians will move like the parts of a mobile, Lewis explained by phone: "You go up on stage and take a card, which has a task assigned to it. You have to walk around without playing in order to do it, and that regulates time."
St. Paul contemporary chamber quartet Zeitgeist, abetted by more than a dozen local improvisers, will perform "Calder" and other Lewis compositions in an event designed to showcase his catalytic impact on music.
"The main thing about these kinds of pieces is that I want people to take responsibility for the musical environment they are creating," Lewis said. "They come together and create sort of momentary community."
Lewis, who will turn 70 in July, is among an elite group of experimental composers alongside John Cage, John Zorn and perhaps a dozen others.
He first came to prominence as a trombonist, but has focused on composing and teaching in recent years. A pioneer in interactive music involving computers, Lewis built his own machines as far back as the mid-1970s, and developed a program in which the computer acts as a member of the ensemble, responding almost intuitively to musical elements such as pitch or timbre.
It would be fair to refer to Lewis as a renaissance man.