Now, Rëaction, as far as we know anything of it, is Action conversed. The general principle of Gravity being, in the first place, understood as the rëaction of an act—as the expression of a desire on the part of Matter, while existing in a state of diffusion, to return into the Unity whence it was diffused; and, in the second place, the mind being called upon to determine the character of the desire—the manner in which it would, naturally, be manifested; in other words, being called upon to conceive a probable law, or modus operandi, for the return; could not well help arriving at the conclusion that this law of return would be precisely the converse of the law of departure. That such would be the case, any one, at least, would be abundantly justified in taking for granted, until such time as some person should suggest something like a plausible reason why it should not be the case—until such period as a law of return shall be imagined which the intellect can consider as preferable.
Matter, then, irradiated into space with a force varying as the squares of the distances, might, à priori, be supposed to return towards its centre of irradiation with a force varying inversely as the squares of the distances: and I have already shown[1] that any principle which will explain why the atoms should tend, according to any law, to the general centre, must be admitted as satisfactorily explaining, at the same time, why, according to the same law, they should tend each to each. For, in fact, the tendency to the general centre is not to a centre as such, but because of its being a point in tending towards which each atom tends
3*
