The very word composition, defined as the "the act of composing; putting together; arranging in proper order," implies that the picture-maker must do something besides setting up his camera and letting it photograph just what happens before it.

The would-be picture-maker must learn to think pictorially; he must try to regard a picture as a pattern, as an arrangement of lines and shapes, making in themselves a pleasing and satisfying design, quite apart from the objects represented. The lines will form certain shapes, and the shapes will vary in tone; some may be light, some dark and some of intermediate shades of gray, which we call halftones.

...I want to make it clear that the success of a picture, as a picture, does not depend upon topographical interest of the subject, but on the ability of the photographer to convey impressions of beauty or interest by his manner of treating it.