“One doesn’t usually know where ideas come from,” says Jasper Johns. But he knows what inspired the set elements he made for Merce Cunningham’s Walkaround Time (part of the Walker collection): looking at a booklet featuring line drawings of Duchamp’s The Large Glass.

Sonic Youth’s Lee Ranaldo, who performs John Cage’s work at the Philadelphia Museum of Art this week, tells Elliott Sharp he loved Cage’s minimal approach: “What is the composer doing when the composer is hardly doing anything? It’s like a Zen poem.”