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

from low to high, ad infinitum; and one single movement from high to low. From low to high, when even the object in motion, going from us to the places situated above our heads, meets ten thousand times with the feet of those who are above us; and from high to low, when in the same way it advances towards the heads of those who are below us. For these two movements, looked at by themselves and in their whole, are conceived as really opposed the one to the other, in their progress towards the infinite.

Moreover, all the atoms are necessarily animated by the same rapidity, when they move across the vacuum, or when no obstacle thwarts them. For why should heavy atoms have a more rapid movement than those which are small and light, since in no quarter do they encounter any obstacle? Why, on the other hand, should the small atoms have a rapidity superior to that of the large ones, since both the one and the other find everywhere an easy passage, from the very moment that no obstacle intervenes to thwart their movements? Movement from low to high, horizontal movement to and fro, in virtue of the reciprocal percussion of the atoms, movement downwards, in virtue of their weight, will be all equal, for in whatever sense the atom moves, it must have a movement as rapid as the thought till the moment when it is repelled, in virtue of some external cause or of its own proper weight, by the shock of some object which resists it.

Again, even in the compound bodies, one atom does not move more rapidly than another. In fact, if one only looks at the continued movement of an atom which takes place in an indivisible moment of time, the briefest possible, they all have a movement equally rapid. At the same time, an atom has not, in any moment perceptible to the intelligence, a continued movement in the same direction; but rather a series of oscillating movements from which there results, in the last analysis, a continued movement perceptible to the senses. If then one were to suppose, in virtue of a reasoning on things invisible, that in the intervals of time accessible to thought the atoms have a continued movement, one would deceive oneself, for that which is conceived by the thought is true as well as that which is directly perceived.

Let us now return to the study of the affections, and of the sensations; for this will be the best method of proving that the soul is a bodily substance composed of slight particles, diffused over all the members of the body, and presenting a great analogy to a sort of spirit, having an admixture of heat, resembling at one time one, and at another time the other of those two principles. There exists in it a special part, endowed with an extreme mobility, in consequence of the exceeding slightness of the elements which compose it, and also in reference to its more immediate sympathy with the rest of the body. That it is which the faculties of the soul sufficiently prove, and the passions, and the mobility of its nature, and the thoughts, and, in a word, everything, the privation of which is death. We must admit that it is in the soul most especially that the principle of sensation resides. At the same time, it would not possess this power if it were not enveloped by the rest of the body which communicates it to it, and in its turn receives it from it, but only in a certain measure; for there are certain affections of the soul of which it is not capable.

It is on that account that when the soul departs the body is no longer possessed of sensation, for it has not this power (that of sensation namely) in itself; but, on the other hand, this power can only manifest itself in the soul through the medium of the body. The soul, reflecting the manifestations which are accomplished in the substance which environs it, realises in itself, in a virtue or power which belongs to it, the sensible affections, and immediately communicates them to the body in virtue of the reciprocal bonds of sympathy which unite it to the body; that is the reason why the destruction of a part of the body does not draw after it a cessation of all feeling in the soul while it resides in the body, provided that the senses still preserve some energy; although, nevertheless, the dissolution of the corporeal covering, or even of any one of its portions, may sometimes bring on with it the destruction of the soul.

The rest of the body, on the other hand, even when it remains either as a whole or in any part, loses all feeling by the dispersion of that aggregate of atoms, whatever it may be, that forms the soul. When the entire combination of the body is dissolved, then the soul too is dissolved, and ceases to retain those faculties which were previously inherent in it, and especially the power of motion; so that sensation perishes equally as far as the soul is concerned, for it is impossible to imagine that it still feels, from the moment when it is no longer in the same conditions of existence and no longer possesses the same movements of existence in reference to the same organic system; from the moment, in short, when the things which cover and surround it are no longer such that it retains in them the same movements as before.

Epicurus expresses the same ideas in other works, and adds that the soul is composed of atoms of the most perfect lightness and roundness; atoms wholly different from those of fire. He distinguishes in it the irrational part which is diffused over the whole body, from the rational part which has its seat in the chest, as is proved by the emotions of fear