David Salle is back with a new show in New York, back at Mary Boone’s gallery, where he came to prominence in the 1980s. “Salle is right up there with Jasper Johns as one of contemporary art’s all-time great question dodgers. Although he was initially viewed as a cynical provocateur, that characterization is no longer useful or even accurate. With the gift of hindsight, he seems more like an art Sphinx. His pictures feed at least partly off Mr. Johns’s use of pop images, and their work is similarly confounding, a box of puzzle pieces that you keep trying to put together only to realize that six pieces are missing on the floor of your hall closet.