You see that all is action in nature, and yet pretend that nature by itself is dead and without power. You imagine that this all, essentially acting, needs a mover! What then is this mover? It is a spirit; a being absolutely incomprehensible and contradictory. Acknowledge then that matter acts of itself, and cease to reason of your spiritual mover, who has nothing that is requisite to put it in action. Return from your tiseless excursions; enter again into a real world; keep to second causes, and leave to divines their first cause, of which nature has no need, to produce all the effects you observe in the world.
It can be only by the diversity of impressions and effects, which bodies make upon us, that we feel them; that we have perceptions and ideas of them; that we distinguish one from another; that we assign them properties. Now, to see and feel an object, the object must act upon our organs; this object cannot act upon us, without exciting some motion in its ; it cannot excite motion in us, if it be not in moti~i itself. At the instant I see an object, my eyes are struck by it; 1 cati have no conception of light and vision, without motion, communicated to my eye, from the luminous, extended, colored body. At the instant I smell a body, my smell is irritated, or put in motion, by the parts that exhale from the odoriferous body. At the moment I hear a sound, the tympanum of my ear is struck by the air, put in motion by a sonorous body, which would not act if it were not in motion itself. Whence it evidently follows, that without motion, I can neither feel, see, distinguish, compare, judge, nor occupy my thoughts upon any subject whatever.
We are taught in the schools, that the essence of a thing, is that from which all its properties flow.* [*Essentia est quid primium in re, fon et radix omnium rei proprietatum] Now it is evident, that all the properties of bodies, of which we have ideas, are owing to motion, which alone informs us of their existence, and gives us the first conceptions of them. I cannot be informed of my own existence but by the motions I experience in myself. I am therefore forced to conclude, that motion is as essential to matter as extension, and that matter cannot be conceived without it.
Should any persons deny, that motion is essential and necessary to matter, they cannot at least help acknowledging that bodies which seem dead and inert, produce motion of themselves, when placed in a fit situation to act upon one another. For instance: phosphorus, when exposed to the air, immediately takes fire. Meal and water, when mixed, ferment. Thus dead matter begets motion of itself. Matter has then the power of self-motion; and nature, to act, has no need of a mover, whose pretended essence would hinder him from acting.