“Since the photographer's picture was not conceived but selected, his subject was never truly discrete, never wholly self-contained. The edges of his film demarcated what he thought most important, but the subject he had shot was something else; it had extended in four directions. …The central act of photography, the act of choosing and eliminating, forces a concentration on the picture edge—the line that separates in from out—and on the shapes that are created by it.” -John Szarkowski, The Photographer’s Eye, 1966