The flatbed picture plane makes its "...symbolic allusion to hard surfaces, or any receptor surface on which objects are scattered, on which data are entered, on which information may be received, printed, impressed - whether coherently or in confusion. It does not simulate vertical fields, but opaque flatbed horizontals. It does not depend on a head-to-toe correspondence with human posture, but insists on an essentially new orientation, in which the painted surface is no longer the analogue of a visual experience of nature but of operational processes… it is not the actual physical placement of the image that counts. It is the psychic address of the image, its special mode of imaginative confrontation, that tends to regard the tilt of the picture plane from vertical to horizontal and is expressive of a radical shift in the subject matter of art, the shift from nature to culture."

Leo Steinberg