Robert Ryman (1930-2019) was a white painter. His medium, as he said, was white paint. The white paint, as some have said, eliminates distraction and reveals the painting in its material facticity. Ryman’s paintings are the sheer material product of a simple process. Painting degree zero. Anything but white is a distraction because other colours refer to other things. Others have said that he continued painting’s long involvement with light, but that his light is real and not depicted, in that his paintings reflect the ambient light in the room. His white is universal and opaque, absorbing signification but reflecting light rays. But others still, most eminently the artist William Pope L., have contended that white’s absorption of signification—its blankness, its universality—is a problem. Is the problem.