When we analyze the principle of this method of seeing, it is found to be that of relativity. In selecting this or rejecting that the artist has been guided by its more or less of value in relation to the whole. The composition, in fact, is an adjusted balance of varieties of values; an interlocked scheme of mutual relations; shrewdly calculated to assert the significance of the whole without undue impairment of the varying character of the parts. And this principle, thus applied to the whole composition, operates also in the treatment of every part. Whether it be the folds of a sash, the modeling of an arm in a sleeve, the substance and set of a ruff, or the construction of a face, each is attained by observing the relation of the values. In this case, however, one uses values, not to measure the amount of relative importance that they play in the general scheme, but in the technical sense of the amount and quality of light reflected from the several facets of the surface. Hals chose to view his subject in a diffused light that permitted practically no shadows, but reduced the whole to a tissue of more light and less light, of higher and lower values. While this sounds like the method of the modern _plein-air_ painters, which has been evolved from the example of Hals and Velasquez, it is not quite the same; for Hals does not represent the light as being independent of the figures and enveloping them, but still adheres to the old convention of making the figure itself a center of light, as, for instance, a lamp is. Thus in one of his groups, where a window appears at the back, the light beyond it is of lower value than that which illumines the figures; and, in another case, a landscape presents a darker background. But, having adopted this convention, he adheres to the logic of it, and, like the modern painter who has followed his example, but with the difference that he tries to represent the effect of _plein-air_, models his forms in colored light by the juxtaposition of the various values. And it is characteristic of Hals that in doing this he overlooks minute distinctions of value, seizing only the most salient ones and laying them on the canvas with a broad brush and a remarkable decision. Thus his technique presents a bold and vigorous generalization of the values; often conspicuous for what it omits, as when he indicates the back of a hat or a ruff by a flat tone that is almost uninterrupted by contrasting tones. It is a technique, in fact, that relies very largely on suggestion; hence its stimulating character, for one’s own imagination is invited to assist in the illusion.