“Space is made by an artist or architect; it is not found and packaged,” said Donald Judd. “It is made by thought.” In fact, Judd wished his work to be “the simple expression of complex thought.” His untitled of 1980—at 80 feet wide the single largest structure he made from Douglas-fir plywood—is the manifestation of a mental process. Its grid configuration makes one think of a computer code, a puzzle box, or, as the artist’s son Flavin Judd has said, a Bach fugue. Untitled was first shown in 1981 at the Castelli Gallery. This is the second time Judd’s monumental work is on view in New York. —E.C.