thing) inertia; and conversely, as I have already pointed out in my first article, we know nothing of mass, except by its relation to force. Mass, inertia (or, as it is sometimes, though inaccurately, called, matter per se), is indistinguishable from absolute nothingness; for matter reveals its presence, or evinces its reality, only by its action, its force, its tension or motion. But, on the other hand, mere force is equally nothing; for, if we reduce the mass upon which a given force, however small, acts until it vanishes—or, mathematically expressed, until it becomes infinitely small—the consequence is that the velocity of the resulting motion is infinitely great, and that the "thing" (if under these circumstances a thing can still be spoken of) is at any given moment neither here nor there, but everywhere—that there is no real presence. It is impossible, therefore, to construct matter by a mere synthesis of forces. And it is incorrect to say, with Bain ("Logic," ii., 225), that "matter, force, and inertia, are three names for substantially the same fact," or that "force and matter are not two things, but one thing," or (ib., p. 389) that "force, inertia, momentum, matter, are all one fact"—the truth being that force and inertia are conceptual constituents of matter, and neither is in any proper sense a fact. Nor is the ordinary analysis of physical reality into matter + force correct, inasmuch as force is already implied in the term matter. It is an analysis of a thing into two elements, one of which is the thing itself. The true formula of matter is mass x force, or inertia x force.
We now have before us, in full view, one of the fundamental fallacies of the atomic theory. This fallacy consists in the delusion that the conceptual constituents of matter can be grasped as separate and real entities. The corpuscular atomists take the element of inertia and treat it as real by itself, while Boscovich, Faraday, and all those who define atoms as "centres of force," seek to realize the corresponding element, force, as an entity by itself. In both cases elements of reality are mistaken for kinds of reality. It is, therefore, sheer nonsense to speak, with Papillon (see the article on the Constitution of Matter in the September number of this journal, p. 553), of a "bare energy, stripped of its material dress;" of a "force in its purest essence, upon which we look as on the marble of the antique, in splendid nakedness, which is radiant beauty too."
This disposes, in my judgment, of the authority of the "scientific imagination," in all cases where an attempt is made to determine the constitution of matter. In respect to the general question, however, whether our ability to imagine a thing is decisive of its possible reality,
- The translation of the passage from which the above is taken, though on the whole admirable, fails to do justice to the magniloquence of the original, which reads thus: "Toutes ces energies n'apparaissent à nous à de rares exceptions près que revêtues de cet uniforme qu'on appelle la matière. Une seule de ces energies se montre dépouillée de ce vêtement et nue. . . . Comment la définir autrement que la force en sa plus pure essence, puisque nous la contemplons comme un marbre antique dans une superbe nudité qui est aussi une beauté radieuse."