The Lives and Opinions of Eminent Philosophers by Diogenes Laërtius (best free ebook reader txt) 📕

perception, any general quality peculiar to all beings which is not either an attribute, or an accident of the body, or of the vacuum.

The same principles are laid down in the first, and fourteenth, and fifteenth book of the treatise on Nature; and also in the Great Abridgment.

Now, of bodies, some are combinations, and some the elements out of which these combinations are formed. These last are indivisible, and protected from every kind of transformation; otherwise everything would be resolved into nonexistence. They exist by their own force, in the midst of the dissolution of the combined bodies, being absolutely full, and as such offering no handle for destruction to take hold of. It follows, therefore, as a matter of absolute necessity, that the principles of things must be corporeal, indivisible elements.

The universe is infinite. For that which is finite has an extreme, and that which has an extreme is looked at in relation to something else. Consequently, that which has not an extreme, has no boundary; and if it has no boundary, it must be infinite, and not terminated by any limit. The universe then is infinite, both with reference to the quantity of bodies of which it is made up, and to the magnitude of the vacuum; for if the vacuum were infinite, the bodies being finite, then, the bodies would not be able to rest in any place; they would be transported about, scattered across the infinite vacuum for want of any power to steady themselves, or to keep one another in their places by mutual repulsion. If, on the other hand, the vacuum were finite, the bodies being infinite, then the bodies clearly could never be contained in the vacuum.

Again: the atoms which form the bodies, these full elements from which the combined bodies come and into which they resolve themselves, assume an incalculable variety of forms, for the numerous differences which the bodies present cannot possibly result from an aggregate of the same forms. Each variety of forms contains an infinity of atoms, but there is not for that reason an infinity of atoms; it is only the number of them which is beyond all calculation.

Epicurus adds, a little lower down, that divisibility ad infinitum is impossible; for, says he, the only things which change are the qualities; unless, indeed, one wishes to proceed from division to division, till one arrives absolutely at infinite littleness.

The atoms are in a continual state of motion.

He says, farther on, that they move with an equal rapidity from all eternity, since the vacuum offers no more resistance to the lightest than it does to the heaviest.

Among the atoms, some are separated by great distances, others come very near to one another in the formation of combined bodies, or at times are enveloped by others which are combining; but in this latter case they nevertheless preserve their own peculiar motion, thanks to the nature of the vacuum, which separates the one from the other, and yet offers them no resistance. The solidity which they possess causes them, while knocking against one another, to react the one upon the other, till at last the repeated shocks bring on the dissolution of the combined body; and for all this there is no external cause, the atoms and the vacuum being the only causes.

He says further on that the atoms have no peculiar quality of their own, except from magnitude and weight. As to color, he says in the twelfth book of his Principia that it varies according to the position of the atoms. Moreover, he does not attribute to the atoms any kind of dimensions; and, accordingly, no atom has ever been perceived by the senses; but this expression, if people only recollect what is here said, will by itself offer to the thoughts a sufficient image of the nature of things.

But, again, the worlds also are infinite, whether they resemble this one of ours or whether they are different from it. For as the atoms are, as to their number, infinite, as I have proved above, they necessarily move about at immense distances; for besides, this infinite multitude of atoms of which the world is formed, or by which it is produced, could not be entirely absorbed by one single world, nor even by any worlds the number of which was limited, whether we suppose them like this world of ours or different from it. There is, therefore, no fact inconsistent with an infinity of worlds.

Moreover, there are images resembling, as far as their form goes, the solid bodies which we see, but which differ materially from them in the thinness of their substance. In fact it is not impossible but that there may be in space some secretions of this kind, and an aptitude to form surfaces without depth, and of an extreme thinness; or else that from the solids there may emanate some particles which preserve the connection, the disposition, and the motion which they had in the body. I give the name of images to these representations; and indeed, their movement through the vacuum taking place, without meeting any obstacle or hindrance, perfects all imaginable extent in an inconceivable moment of time; for it is the meeting of obstacles or the absence of obstacles, which produces the rapidity or the slowness of their motion. At all events, a body in motion does not find itself, at any moment imaginable, in two places at the same time; that is quite inconceivable. From whatever point of infinity it arrives at some appreciable moment, and whatever may be the spot in its course in which we perceive its motion, it has evidently quitted that spot at the moment of our thought; for this motion which, as we have admitted up to this point, encounters no obstacle to its rapidity, is wholly in the same condition as that the rapidity of which is diminished by the shock of some resistance.

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