II.
The second theory admits only forces in nature, and places in these forces the principle of all that is produced. It also goes up to the atom, and considers it as equally indivisible and imponderable. It attributes to matter properties, so to speak, immanent which give it its power and action. Atoms, separated from each other in the bodies which they compose, and forming mere simple mathematical points, possess, when they are reunited in mass, a force of attraction which acts at a distance, and then reacts on them in order to produce all the sensible phenomena.
Several savants and certain spiritualist philosophers agree on this theory. Both take facts as the starting point in establishing their synthesis; the former build it on a foundation more exclusively physical; the latter give to their generalization a more philosophical basis.
M. Magy and M. Laugel, hardly overstepping the limits of the experimental world, follow the action of forces into their different modes and transformations.
M. Paul Janet, in his turn, delivers his theory on matter.[202]
"It is in fact," he writes, "force and not extent which constitutes the essence of bodies; an atom in motion occupies successively places which it fits exactly. What distinguishes this atom from the space previously occupied by it? It is not the extent, since in both cases the shape is the same; every thing which relates to extent is absolutely identical in the empty and in the full atom. It is, therefore, something else which distinguishes them, and this something is solidity or weight; but neither solidity nor weight is a modification of extent; both are derived from force, and represent it."
M. Ch. Lévêque adds:[203]
"How do we make the extension which we need? Always by resistance; when extension is not a pure abstraction, when it is real and concrete, it is always equivalent to a sum of resisting points or forces. There is no longer occasion to ask how, with unextended elements, we may form extension. There is but one question possible, and it is this: How to form a sum of resistance with resisting points?"
This is what a learned Englishman, P. Bayma, establishes with precision.[204] According to him, the elements, or atoms, are indivisible points without material extent, and extension is not an essential property of matter.