lightning performs an immense work. However this may be, it is impossible to think of the energies that make up the atom otherwise than as of pure force, and the ether itself, whose existence is demonstrated by the whole of physics, can be no otherwise defined than by the attributes of force. It follows from this that atoms, the last conclusion of chemistry, and ether, the last conclusion of physics, are substantially alike, although they form two distinct degrees, two unequal values, of the same original activity. All those physico-chemical energies, as well as the analogous energies of life, only show themselves to us, save in rare exceptions, clothed with that uniform we call matter. A single one of these energies shows forth, stripped of this dress, and bare. It rules all the others, because it knows them all without their knowing it. It is not power merely, but consciousness besides. It is the soul. How define it otherwise than as force in its purest essence, since we look upon it, as on the marble of the antique, in splendid nakedness, which is radiant beauty too?
Whether we consider coarser matter which can be weighed and felt, or that more subtle, lively, and active matter we call ether, or again the spiritual principle, which is energy simple, we have then always before us only harmonious collections of forces, symmetrical activities, ordered powers, more or less conscious of the part they play in the infinite concert for which the Creator has composed the glorious music. Let us set aside for a moment the variety of groupings which determine the succession and the manifold aspects of these forces, and there will remain, as constituent principles of the web of the universe, as irreducible and primordial ingredients of the world, nothing but dynamic points, nothing but monads.
The term of the rigorous analysis of phenomena is, definitively, the conception of an infinity of centres of similar and unextended forces, of energies without forms, simple and eternal. We ask what these forces are, and we assert in answer that it is impossible to distinguish them from motion. Force may be conceived, but not shaped to the fancy. The clearest and truest thing we can say of it is, that it is an energy analogous to that whose constant and undeniable presence we feel dwelling in our deepest selves. "The only force of which we have consciousness," says Henry Sainte-Claire Deville, "is will." Our soul, which gives us consciousness of force, is also the type of it, in this sense that, if we wish to pierce to the elementary mechanisms of the world, we are imperiously driven to compare its primal activities with the only activity of which we have direct knowledge and intuition, that is to say, with that admirable spring of will, so prompt and sure, which permits us every moment to create and also to guide motion.
Motion may serve to measure force, but not to explain it. It is as subordinate to the latter as speech is to thought. In truth, motion is nothing else than the series of successive positions of a body in different points of space. Force, on the other hand, is the tendency, the
