Finally the notion that the picture is a representation of depth as well as length and height develops the idea of balance in the chain of items from foreground to distance. A pivotal space then will be found, a neutral ground in the farther stretch from which may be created so much attraction as to upend the foreground, or in the nether reach toward us there may be such attraction as to leave the distance without its weight in the convention of parts. The group with insufficient attraction back of it topples toward us, to be sustained within the harmonious circuit of the picture only by such items of attraction behind it as will recover a balance which their absence gave proof of. This is a more subtle but none the less potent influence than the vertical and lateral balance and may best be apprehended negatively. The “aggressiveness ” of many foreground items which are in themselves essential as form and correct in value is caused by the lack of their balancing complements in the back planes of the picture.
Balance is not of necessity dependent upon objects of attraction. Its essence lies in the movement from one part of the picture to an-other, which the arrangement compels, and this may often be stimulated by the intention or suggestion of movement in a given direction.