The sculpture of ancient Egypt is an instance of great unity in conception, and the suppression of variety to a point at which life scarcely exists. The lines of the Egyptian figures are simple and long, the surfaces smooth and unvaried, no action is allowed to give variety to the pose, the placing of one foot a little in front of the other being alone permitted in the standing figures; the arms, when not hanging straight down the sides, are flexed stiffly at the elbow at right angles; the heads stare straight before them. The expression of sublimity is complete, and this was, of course, what was aimed at. But how cold and terrible is the lack of that play and variety that alone show life. What a relief it is, at the British Museum, to go into the Elgin Marble room and be warmed by the noble life pulsating in the Greek work, after visiting the cold Egyptian rooms.
In what we call a perfect face it is not so much the perfect regularity of shape and balance in the features that charms us, not the things that belong to an ideal type, but rather the subtle variations from this type that are individual to the particular head we are admiring. A perfect type of head, if such could exist, might excite our wonder, but would leave us cold. But it can never exist in life; the slightest movement of the features, which must always accompany life and expression, will mar it. And the influence of these habitual movements on the form of the features themselves will invariably mould them into individual shapes away from the so-called perfect type, whatever may have been nature's intention in the first instance.
If we call these variations from a common type in the features imperfections, as it is usual to do, it would seem to be the imperfections of perfection that charm and stir us; and that perfection without these so-called imperfections is a cold, dead abstraction, devoid of life: that unity without variety is lifeless and incapable of touching us.
On the other hand, variety without unity to govern it is a riotous exuberance of life, lacking all power and restraint and wasting itself in a madness of excess.
So that in art a balance has to be struck between these two opposing qualities. In good work unity is the dominating quality, all the variety being done in conformity to some large idea of the whole, which is never lost sight of, even in the smallest detail of the work. Good style in art has been defined as "variety in unity," and Hogarth's definition of composition as the art of "varying well" is similar. And I am not sure that "contrasts in harmony" would not be a suggestive definition of good colour.
Let us consider first variety and unity as they are related to line drawing, and afterwards to mass drawing.