The Lives and Opinions of Eminent Philosophers

by Diogenes Laertius

XL. These now were his chief opinions. He affirmed that the soul was immortal and clothed in many bodies successively, and that its first principle was number, and that the first principle of the body was geometry. And he defined it as an abstract idea of spirit diffused in every direction. He said also, that it was self-moving and threefold. For that that part of it which was capable of reasoning was situated in the head, that that portion which was affected by passion was seated around the heart, and that which was appetitive was placed around the navel and the liver. And that it is placed in the middle of the body, and embraces it at the same time in all its parts, and that it consists of elements; and that when it is divided according to harmonic intervals it forms two connected circles; of which the inner circle is divided into six portions, and makes in all seven circles; and that this is placed on the left hand of the diameter, and situated in the interior. But the other is on the right hand of the same line; on which account, and because it is one only, it is the superior of the two. For the other is divided internally; and this too, is the circle of that which is always the same; the other, the circle of that which is changeable and different. And the one he says is the motion of the soul, but the other is the motion of the universe and of the planets.

On the other side, the division of the circles from the centre to the extremities, being harmoniously appropriated to the essence of the soul, the one knows existing things and establishes harmony between them, because it is itself composed of harmonious elements. The circle of what is changeable, engenders opinion by its regular movements; but the circle of that which is always the same produces knowledge.

XLI. Plato lays down two primary causes or principles of all things, God and matter, which he also calls mind, and the cause. And he defines matter as something without shape and without limitation, and says that from it all concretions arise. He affirms also that as it was moving about at random, it was brought by God into one settled place, as God thought order better than disorder; and that this nature is divided into four elements, fire, water, air, and earth, of which the world itself and everything in it was made. But he says that the earth is the only thing that is unchangeable, as he considers the cause to be the difference of the figures of which it is composed; for he says that the figures of the others are homogeneous; for that they are all composed equally of scalene triangles. The figure of the earth, however, is peculiar to itself; for the element of fire is a pyramid; of air, an octagon; of water, an eicosagon; and of the earth, a cube; owing to which these things cannot be changed into earth, nor earth into them. He teaches also that these elements are not separated so as to occupy each a peculiar and distinct place; for the spherical motion collects and compresses all the small things towards the centre, and the small things separate the great ones, on which account the species, as they change, do also change their positions.

Moreover he asserts that the world is one, and has been produced, since it has been made by God, in such a manner as to be an object of sensation. And he considers it endowed with life, because that which is so endowed, is superior to that which is not, and it must be the production of the most excellent producer. It is also one, and illimitable; because the model after which it was made was one; and it is spherical, because its creator was of that form; for it also contains all other animals, and God who made it comprises all forms. And it is smooth, and has no instruments whatever all round it, because it has no need of any. But the whole world remains imperishable, because it cannot be resolved into God; and God is the cause of universal production, because it is the nature of the good to be productive of good; and the best is the cause of the production of the heaven; for the best of all productions can have no other cause than the best of all intelligible existences. And since God is of that character, and since heaven resembles the best, inasmuch as it is at least the most beautiful of all things, it cannot be like anything else that is produced, except God.

He also teaches that the world consists of fire, water, air, and earth; of fire, in order that it may be visible; of earth, in order that it may be firm; of water and air, that it may not be destitute of proportion; for two middle terms are indispensable to keep the solid bodies in due proportion to one another, and to realize the unity of the whole. In short, the world is formed of all the elements together, in order that it may be perfect and imperishable.

Again, time is the image of eternity; eternity subsists for ever; but the motion of the heaven is time; for day, and night, and the months, and all such divisions, are parts of time, on which account there could be no such thing as time apart from the nature of the world; for time existed contemporaneously and simultaneously with the world. And it was with reference to time that the sun, and the moon, and the planets were made; and it was in order that the number of the seasons might be manifest, and that the animals might partake of number, that God kindled the light of the sun; and that the moon was above the circle of the earth, and that the sun was next to it, and in the still higher circles were the planets. And that the universe was animated, because it was altogether bound up in animated motion, and that the race of all other animals was produced in order that the world might be made perfect, and resembling an animal such as could be comprehended by intellect. Since then God had life, the heaven also must have life; and the Gods are to a great extent composed of fire. And there are three other races of animals, those which fly in the air; those which live in the water; those which walk in the earth. The oldest of all the deities in heaven is the Earth; she was formed in order to be the dispenser of night and day; and as she is placed in the centre, she is constantly in motion around the centre.

And since there are two efficient causes, some things must, he says, be affirmed to exist in consequence of intellect, and some from some necessary cause. Now necessary causes are the air, fire, earth, and water, these not being real elements, but rather receptacles; and they too are formed of triangles in combination, and are resolvable into triangles; and their elements are the scalene triangle and the isosceles. These two before mentioned elements are the principles and causes of things, of which the models are God and matter, which last must necessarily be destitute of form, as is the case of other receptacles. And that the cause of these things was a necessary cause, which, receiving the ideas, produced the substances, and was moved by the dissimilarity of its own power, and again by its motion compelled those things which were moved by it to move other things in their turn.

But all these things were formerly moved without any reason or order; but after they began to form the world by their combination, they then received symmetry and regularity from God, according to the principles applicable to them; for the efficient causes, even before the creation of the heaven, were two in number. There was also a third, namely production; but these were not very evident, but rather traces than actual things, and quite devoid of regularity. But after the world was made, then they too assumed a regular form and arrangement; but the heaven was made of all existing bodies. And Plato considers that God is incorporeal just as the soul is, and that it is owing to that that he is not affected by any destruction or external circumstances. And ideas, as we have said before, he defines as certain causes and principles, owing to which it is that such and such things are by nature what they are.

XLII. On the subject of good and evil, these were his sentiments: that the end was to become like God; and that virtue was sufficient of herself for happiness, but nevertheless required the advantages of the body as instruments to work with; such as health, strength, the integrity of the senses, and things of that kind; and also external advantages, such as riches, and noble birth, and glory. Still that the wise man would be not the less happy, even if destitute of these auxiliary circumstances; for he would enjoy the constitution of his country, and would marry, and would not transgress the established laws, and that he would legislate for his country, as well as he could under existing circumstances, unless he saw affairs in an unmanageable condition, in consequence of the excessive factiousness of the people. He thinks too that the Gods superintend all the affairs of men, and that there are such beings as dæmons. And he was the first person who defined the notion of the honourable, as that which borders on the praiseworthy, and the logical, and the useful, and the becoming, and the expedient, all which things are combined with that which is suitable to, and in accordance with, nature.

XLIII. He also discussed in his dialogues the correctness of terms, so that he was the first person who reduced the science of giving correct answers, and putting correct questions to a system, which he himself used to satiety.