Hopper was 81 when he painted Sun in an Empty Room, his last great painting. The original plan for the picture included a human figure, but in the end, the patch of light and the wind-swept trees were enough. "Whether we like it or not," Hopper wrote, "we are all bound to the earth with our experience of life and the reactions of the mind, heart, and eye, and our sensations, by no means, consist entirely of form, color, and design." This was meant as a swipe at the Abstract Expressionists working a few blocks north of Washington Square, and yet—as that "by no means" suggests—Hopper's vision was pushing him inexorably toward abstraction. Sun in an Empty Room has the meditative weight of Rothko's saturated canvases as well as something of Richard Diebenkorn's refracted light in his California paintings of the 1960s. Hopper, and American art, had come a long way since Summer Interior, but that patch of light on the floor carries a similar emotional freight. The empty space is not so much unfurnished as cleared of furniture, like a room for rent, or an opening for the unconscious. The room feels inhabited—as Wallace Stevens once wrote—by "nothing that is not there and the nothing that is."