Page:The System of Nature.djvu/62

 with these parts, that are, analogous to it, and with those particles which are light and subtle; water carries off that which is suitable to liquescency; fire, bursting its chains, disengages itself, and rushes into new combinations with other bodies.

The elementary particles of the animal, being thus dissolved, disunited, and dispersed; assume new activity, and form new combinations: thus, they serve to nourish, to preserve, or destroy new beings; among others, plants, which arrived at their maturity, nourish and preserve new animals; these in their turn yielding to the same fate as the first.

Such is the constant, the invariable course, of Nature; such is the eternal circle of mutation, which all that exists is obliged to describe. It is thus motion generates, preserves for a time, and successively, destroys, one part of the universe by the other; whilst the sum of existence remains eternally the same. Nature, by its combinations, produces suns, which place themselves in the centre of so many systems: she forms planets, which, by their peculiar essence, gravitate and describe their revolutions round these suns: by degrees the motion is changed altogether, and becomes eccentric: perhaps the day may arrive when these wondrous masses will disperse, of which man, in the short space of his existence, can only have a faint and transient glimpse.

It is clear, then, that the continual motion inherent in matter, changes and destroys all beings; every instant depriving them of some of their properties, to substitute others: it is motion, which, in thus changing their actual essence, changes also their order, their direction, their tendency, and the laws which regulate their mode of acting and being: from