LeWitt began making pictures of squares arranged in simple, serial patterns. He also began making what he called "structures" based on the elemental shape of a cube. "For LeWitt, ... Muybridge's approach offered a way of creating art that did not rely on the whim of the moment but on a consistently thought out process that gave results that were interesting and exciting," wrote [Andrea Miller-Keller] in "Of Sun and Stars: [Sol LeWitt] Wall Drawings," her catalog for the 1996 Sao Paulo Bienal, in which she and LeWitt participated as representatives of the United States. "Seriality also meant that all of the parts were only the result of the basic idea that each individual part was equally important, and that all parts were equal -- nothing hierarchical."

By the mid-1960s, LeWitt had begun to experiment with wall drawings, an idea that was radical for a number of reasons. For starters, LeWitt was drawing directly on the wall -- not on canvas, not on paper. Wall drawings were, by their nature, impermanent, their evanescence challenging the question of art, collection and value. LeWitt's drawings were designed to be painted over. When, in 1968, the New York gallery owner Paula Cooper was faced with painting out LeWitt's first-ever wall drawing, she couldn't do it. She was unable "to destroy something of such beauty," she said. She insisted LeWitt come and do it himself, which he did without flinching.

LeWitt's support and philanthropy was not confined to the art world. Chester's Congregation Beth Shalom synagogue, dedicated in 2001, "probably wouldn't exist without the LeWitts," said [Lary Bloom]. The structure, resembling an Eastern European synagogue, was designed by architect Steven Lloyd from sketches created by LeWitt. Over the years, Sol and Carol LeWitt together amassed a major private art collection, much of it the result of their purchases and of LeWitt's habit of trading with fellow artists.