De Anima

In our enquiry concerning soul it is necessary to state the problems which must be solved as we proceed, and at the same time to collect the views of our predecessors who had anything to say on the subject, in order that we may adopt what is right in their conclusions and guard against their mistakes. Our enquiry will begin by presenting what are commonly held to be in a special degree the natural attributes of soul. Now there are two points especially wherein that which is animate is held to differ from the inanimate, namely, motion and the act of sensation: and these are approximately the two characteristics of soul handed down to us by our predecessors. There are some who maintain that soul is preeminently and primarily the cause of movement. But they imagined that that which is not itself in motion cannot move anything else, and thus they regarded the soul as a thing which is in motion. Hence Democritus affirms the soul to be a sort of fire or heat. For the"shapes" or atoms are infinite and those which are spherical he declares to be fire and soul: they may be compared with the so-called motes in the air, which are seen in the sunbeams that enter through our windows. The aggregate of such seeds, he tells us, forms the constituent elements of the whole of nature (and herein he agrees with Leucippus), while those of them which are spherical form the soul, because such figures most easily find their way through everything and, beings themselves in motion, set other things in motion. The atomists assume that it is the soul which imparts motion to animals. It is for this reason that they make life depend upon respiration. For, when the surrounding air presses upon bodies and tends to extrude those atomic shapes which, because they are never at rest themselves, impart motion to animals, then they are reinforced from outside by the entry of other like atoms in respiration, which in fact, by helping to check compression and solidification, prevent the escape of the atoms already contained in the animals; and life, so they hold, continues so long as there is strength to do this. The doctrine of the Pythagoreans seems also to contain the same thought. Some of them identified soul with the motes in the air, others with that which sets these motes

in motion: and as to these motes it has been stated that they are seen to be in incessant motion, even though there be a perfect calm. The view of others who describe the soul as that which moves itself tends in the same direction. For it would seem that all these thinkers regard motion as the most distinctive characteristic of the soul. Everything else, they think, is moved by the soul, but the soul is moved by itself: and this because they never see anything cause motion without itself being in motion. Similarly the soul is said to be the moving principle by Anaxagoras and all others who have held that mind sets the universe in motion; but not altogether in the same sense as by Democritus. The latter, indeed, absolutely identified soul and mind, holding that the presentation to the senses is the truth: hence, he observed, Homer had well sung of Hector in his swoon that he lay "with other thoughts." Democritus, then, does not use the term mind to denote a faculty conversant with truth, but regards mind as identical with soul. Anaxagoras, however, is less exact in his use of the terms. In many places he speaks of mind as the cause of goodness and order, but elsewhere he identifies it with the soul: as where he attributes it to all animals, both great and small, high and low. As a matter of fact, however, mind in the sense of intelligence would not seem to be present in all animals alike, nor even in all men.

Those, then, who have directed their attention to the motion of the animate being, conceived the soul as that which is cognitive, most capable of causing motion: while those who laid stress on its knowledge and perception of all that exists identified the soul with the ultimate principles, whether they recognised a plurality of these or only one. Thus Empedocles compounded soul out of all the elements, while at the same time regarding each one of them as a soul. His words are "With earth we see earth, with water water, with air bright air, but ravaging fire by fire, love by love, and strife by

gruesome strife." In the same manner Plato in the Timaeus constructs the soul out of the elements. Like, he there maintains, is known by like, and the things we know are composed of the ultimate principles. In like manner it was explained in the lectures on philosophy, that the self-animal or universe is made up of the idea of One, and of the idea-numbers Two, or primary length, Three, primary breadth, and Four, primary depth, and similarly with all the rest of the ideas. And again this has been put in another way as follows: reason is the One, knowledge is the Two, because it proceeds by a single road to one conclusion, opinion is the number of a surface, Three, and sensation the number of a solid, Four. In fact, according to them the numbers, though they are the ideas themselves, or the ultimate principles, are nevertheless derived from elements. And things are judged, some by reason, others by knowledge, others again by opinion and others by sensation: while these idea-numbers are forms of things. And since the soul was held to be thus cognitive as well as capable of causing motion, some thinkers have combined the two and defined the soul as a self-moving number.

But there are differences of opinion as to the nature and number of the ultimate principles, especially between those who make the principles corporeal and those who make them incorporeal; and again between both of these and others who combine the two and take their principles from both. But, further, they differ also as to their ro number: some assuming a single principle, some a plurality. And, when they come to give an account of the soul, they do so in strict accordance with their several views. For they have assumed, not unnaturally, that the soul is that primary cause which in its own nature is capable of producing motion. And this is why some identified soul with fire, this being the element which is made up of the finest particles and is most nearly incorporeal, while further it is preeminently an element which both moves and sets other things in motion. Democritus has expressed more neatly the reason for each of these facts. Soul he regards as identical with mind, and this he makes to consist of the primary indivisible bodies and considers it to be a cause of motion from the fineness of its particles and their shape. Now the shape which is most susceptible of

motion is the spherical; and of atoms of this shape mind, like fire, consists. Anaxagoras, while apparently understanding by mind something different from soul, as we remarked above, really treats both as a single nature, except that it is preeminently mind which he takes as his first principle; he says at any rate that mind alone of things that exist is simple, unmixed, pure. But he refers both knowledge and motion to the same principle, when he says that mind sets the universe in motion. Thales, too, apparently, judging from the anecdotes related of him, conceived soul as a cause of motion, if it be true that he affirmed the loadstone to possess soul, because it attracts iron. Diogenes, however, as also some others, identified soul with air. Air, they thought, is made up of the finest particles and is the first principle: and this explains the fact that the soul knows and is a cause of motion, knowing by virtue of being the primary element from which all else is derived, and causing motion by the extreme fineness of its parts. Heraclitus takes soul for his first principle, as he identifies it with the vapour from which he derives all other things, and further says that it is the least corporeal of things and in ceaseless flux; and that it is by something in motion that what is in motion is known; for he, like most philosophers, conceived all that exists to be in motion. Alcmaeon, too, seems to have had a similar conception. or soul, he maintains, is immortal because it is like the beings which are immortal; and it has this attribute in virtue of being ever in motion: for he attributes continuous and unending motion to everything which is divine, moon, sun, stars and the whole heaven. Among cruder thinkers there have been some, like Hippon, who have even asserted the soul to be water. The reason for this view seems to have been the fact that in all animals the seed is moist: in fact, Hippon refutes those who make the soul to be blood by pointing out that the seed is not blood, and that this seed is the rudimentary soul. Others, again, like Critias, maintain the soul to be blood, holding that it is sentience which is most distinctive of soul and that this is due to the nature of blood. Thus each of the four elements except earth has found its supporter. Earth, however,

has not been put forward by anyone, except by those who have explained the soul to be derived from, or identical with, all the elements.

Thus practically all define the soul by three characteristics, motion, perception and incorporeality; and each of these characteristics is referred to the ultimate principles. Hence all who define soul by its capacity for knowledge either make it an element or derive it from the elements, being on this point, with one exception, in general agreement. Like, they tell us, is known by like; and therefore, since the soul knows all things, they say it consists of all the ultimate principles. Thus those thinkers who admit only one cause and one element, as fire or air, assume the soul also to be one element; while those who admit a plurality of principles assume plurality also in the soul. Anaxagoras alone says that mind cannot be acted upon and has nothing in common with any other thing. How, if such be its nature, it will know anything and how its knowledge is to be explained, he has omitted to state; nor do his utterances afford a clue. All those who introduce pairs of opposites among their principles make the soul also to consist of opposites; while those who take one or other of the two opposites, either hot or cold or something else of the sort, reduce the soul also to one or other of these elements. Hence, too, they etymologise according to their theories; some identify soul with heat, deriving ζῆν from ζεῖν, and contend that this identity accounts for the word for life; others say that what is cold is called soul from the respiratory process and consequent"cooling down," deriving ψυχή from ψύχειν. Such, then, are the views regarding soul which have come down to us and the grounds on which they are held.