To learn to see pictorially is the first essential duty of the would-be picture-maker. - Arthur Hammond

The picture-space should be filled, but need not be crowded, and it must be remembered that in judging balance, not only the masses of the subject, but also the shapes of the area remaining after being cut into by the outlines of these masses, have a bearing on the general design of the picture.

The areas of tones are called masses and, whatever the subject of picture may be, its success as a picture depends very largely on the effectiveness of the spacing and massing.

...I would recommend the photographer to regard the focusing-screen of his camera as a space to be divided into a pleasing pattern, rather than as a glass on which a reduced facsimile of a scene or view or a miniature likeness of a person can be seen.