Leucippus and Democritus, of course, were not troubled with the problems raised by such phenomena as we have just been considering, since they knew nothing about them. For the founders of Atomism, a multiplicity of substances, living matter, and consciousness could readily be accounted for by the varied combination of variously formed atoms, physically considered. What would be their astonishment to learn that tens of thousands of different substances are actually composed of only four kinds of atoms--viz., hydrogen, oxygen, nitrogen and carbon! Yet for them _one_ element, qualitatively considered, was sufficient to produce all that is--including the “soul”--provided this primal matter existed in an infinite number of shapes and sizes of atomic dimensions. DEMOCRITEAN COLOR THEORY “We have no exact information,” says Professor Gompertz, “as to which bodies in the theory of Democritus were simple and which were complex,” but he adduces evidences to show that “the infinite multiplicity which Democritus recognized in the sizes and shapes of atoms did not arise from his incompetence to perceive or to conjecture a complex in an apparently simple body.” He remarks that the Democritean theory of color started from the assumption of four primary colors--white, black, red and green. “These, with the exception of green, which had taken the place of yellow, were likewise the primary colors in the scheme of Empedocles.” But all other colors “were designated as _mixed_, and we see that all the numerous bodies which were not equipped with one of the four primary colors must have been of a composite nature. That is to say, they must have included other than merely homogenously elementary particles.... The statements about the atomic forms underlying the several tastes give rise at first impression (to the idea that) each of the countless ‘juices’ or materials of taste is composed of homogeneous atoms possessing the size and shape required for the purpose. “But this, we plainly perceive, was not the opinion of Democritus. His own view of the mixed colors cries against it. The homogeneity of the atoms was admissible in the case of white salt, but it was not admissible in that of yellow-gold honey or of brownish-yellow human bile. It is true that he must have referred the sweetness of the one and the bitterness of the other to the presence of the atomic forms by which these impressions were produced. But yellow and brown were mixed colors in his theory, and he must accordingly have inferred that honey and bile alike contained atoms of other forms as well.”