of chemical science, of a true generalization of the phenomena of combination in definite proportions, both of weight and volume, which is independent of the atomic doctrine, and will serve to connect a number of concomitant facts for which this doctrine is utterly incompetent to account.
It is not infrequently asserted by the advocates of the atomic theory that there is a number of other phenomena, in addition to those of combination in definite proportions, which are strongly indicative of the truth of the atomic theory. Among these phenomena are isomerism, polymerism, and allotropy. But it is very doubtful whether this theory is countenanced by the phenomena in question. The existence of different allotropic states, in an elementary body said to consist of but one kind of atoms, is explicable by the atomic hypothesis in no other way than by deducing these different states from diversities in the grouping of the different atoms. But this explanation applies to solids only, and fails in the cases of liquids and gases. The same remark applies to isomerism and polymerism.
From the foregoing considerations, I take it to be clear that the atomic hypothesis mistakes many of the facts which it seeks to explain; that it accounts imperfectly or not at all for a number of other facts which are correctly apprehended; and that there are cases in which it appears to be in irreconcilable conflict with the data of experience. As a physical theory, it is barren and useless, inasmuch as it lacks the first requisite of a true theory—that of being a generalization, a reduction of several facts to one; it is essentially one of those spurious figments of the brain, based upon an ever-increasing multiplicatio entium praeter necessitatem, which are characteristic of the pre-scientific epochs of human intelligence, and against which the whole spirit of modern science is an emphatic protest. Moreover, in its logical and psychological aspect, as we shall hereafter see more clearly, it is the clumsiest attempt ever made to transcend the sphere of relations in which all objective reality, as well as all thought, has its being, and to grasp the absolute "ens per sese, finitum, reale, totum."
I do not speak here of a number of other difficulties which emerge upon a minute examination of the atomic hypothesis in its two principal varieties, the atoms being regarded by some physicists as extended and figured masses, and by others as mere centres of force. In the former case the assumption of physical indivisibility becomes gratuitous, and that of mathematical indivisibility absurd; while in the latter case the whole basis of the relation between force and mass, or rather force and inertia, without which the conception of either term of the relation is impossible, is destroyed. Some of these difficulties are frankly admitted by leading men of science for instance, by Du Bois-Reymond, in the lecture above cited. Nevertheless, it is asserted that the atomic, or at least molecular, constitution of matter
