The subject isolated by the viewing frame is the most passive type of composition. The photographer has no other starting point, however much he may alter the aspect of the subject with the refinements of optical instruments. But the draftsman is not tied to an irrevocably inclusive subject; he can leave things out or introduce distant or imagined things.
In any case, the isolated subject cannot prevent the beholder asking what happens beyond its borders. However full the composition and however detailed the rendering, however much it aims at being a slice of reality, it can give only a part, perhaps the essential part, of the incident it portrays but never the whole of it. On the other hand, a drawing may be placed in an empty space without arousing curiosity in the beholder, if there is nothing to awaken it.
It does not matter whether the picture is a drawing on white paper, grows in color out of a tinted ground, or, as so often happens in the work of Rembrandt, emerges as light against a dark ground; what is important is how the subject is placed in the "empty" space. This is for the most part the basis of composition in modern murals which no longer fill the whole wall inside the architectural framework but leave large areas untouched inside these limits. On very large areas a small mural painting will act only as a center of gravity. The subject itself cannot then use the emptiness of the surface as a supporting field but must free itself from it.
Apart from a few rare aberrations, the shape of pictures has always remained one of three regular geometrical figures: rectangle, circle, or ellipse. The center of gravity of these areas, the geographical center, is virtually never the right center of gravity for the pictorial composition, since it constitutes an indifferent balance. A hanging picture requires a stable equilibrium, which necessitates raising the center of gravity above the center point. It then forms the beginning of a symmetrical composition rather like the summit of the "figura pyramidale" so beloved in the Italian Renaissance.
Central and symmetrical composition underlines ceremonial, sacred themes. It is often supported by a central perspective. Art historians have made great efforts to formulate a series of schemes of composition from the famous masterpieces, assiduously drawing diagonals and triangles, circles, ellipses, and arcs, not noticing in their zeal that linear construction alone can never fully render the effects of areas. Even if such analyses are carried out more realistically, nothing more emerges than certain similarities in the arrangement of areas which are hardly capable of explaining the individual peculiarities of the compositions.
The artist can build only a very trite composition by constructing in this way. His feeling works more correctly and, in a higher sense, more logically for him. Besides, there are other centers in the composition that cannot be traced with areas and lines at all, such as, for instance, the empty space that takes up the turn of a body or a head which would otherwise jump out of the plane of the picture, or the high, wide expanse of sky which can express nobility, burden, menace, and many other sensations, according to what else is happening in the picture. The classical painters of the Far East were past masters in the art of using this empty space.
When we discuss composition in color it will be seen that when one seeks really to interpret a composition one almost needs a model in the round. Weight, movement, and projecting or receding effects of color cannot be understood through drawn lines and areas. The essence of a composition cannot be reduced to the formal arrangement of the plane of a picture, which is something very superficial. It is much more concerned with the dynamic of depth. The position and expression of the eye, for instance, is the only way of depicting which way a figure is looking. The path of the look cannot be represented, but, compared with the small dot representing the eye, it has a tremendous pull in the composition. This is proved by the welltried rule that there must be much more free space within the field of a figure's vision than outside it. Perspective has the same pull, so do light and shadow.
A flight of perspective can lead the beholder's eye to an imaginary point which is not represented but which nonetheless works as the center of gravity of the picture or as a counterweight to some clearly portrayed center. Light, again, does not make its only effect by the small patch represented but often by a path which may be merely indicated only by a few illuminated points rather than a continuous shaft. These are just a few samples of the endless possibilities. Another is shadow with its contribution of dark areas and indications of direction.
An entirely new concept of composition arose with Impressionism. Hitherto, the weight and stress of the composition had always been confined within the edges of the picture. Now there arose a disharmony between the incident in the picture and its borders. The beholder feels the urge to pull the subject back into position, and since he is unable to do this his interest is excited and 'held. It is the same sensation as that given by a piece of music ending on a discord.