November 5, 2018

Physic

We have now before us the main facts with regard to the Stoic view of man's nature, but we have yet to see in what setting they were put. What was the Stoic outlook upon the universe? The answer to this question is supplied by their Physic.

There were, according to the Stoics, two first principles of all things, the active and the passive. The passive was that unqualified being which is known as Matter. The active was the Logos, or reason in it, which is God. This, it was held, eternally pervades matter and creates all things. This dogma, laid down by Zeno, was repeated after him by the subsequent heads of the school.

There were then two first principles, but there were not two causes of things. The active principle alone was cause, the other was mere material for it to work on—inert, senseless, destitute in itself of all shape and qualities, but ready to assume any qualities or shape.

Matter was defined as that out of which anything is produced. The Prime Matter, or unqualified being, was eternal and did not admit of increase or decrease, but only of change. It was the substance or being of all things that are.

The Stoics, it will be observed, used the term "matter" with the same confusing ambiguity with which we use it ourselves, now for sensible objects which have shape and other qualities, now for the abstract conception of matter, which is devoid of all qualities.

Both these first principles, it must be understood, were conceived of as bodies, though without form, the one everywhere interpenetrating the other. To say that the passive principle, or matter, is a body comes easy to us, because of the familiar confusion adverted to above. But how could the active principle, or God, be conceived of as a body? The answer to this question may sound paradoxical. It is because God is a spirit. A spirit in its original sense meant air in motion. Now the active principle was not air, but it was something which bore an analogy to it—namely aether. Aether in motion might be called a 'spirit' as well as air in motion. It was in this sense that Chrysippus defined the thing that is, to be a spirit moving itself into and out of itself, or spirit moving itself to and fro.

From the two first principles which are ungenerated and indestructible must be distinguished the four elements which, though ultimate for us, yet were produced in the beginning by God and are destined some day to be reabsorbed into the divine nature. These with the Stoics were the same which had been accepted since Empedocles—namely earth, air, fire and water. The elements, like the two first principles were bodies; unlike them, they were declared to have shape as well as extension.

An element was defined as that out of which things at first come into being and into which they are at last resolved. In this relation did the four elements stand to all the compound bodies which the universe contained. The terms earth, air, fire and water had to be taken in a wide sense: earth meaning all that was of the nature of earth, air all that was of the nature of air and so on. Thus, in the human frame, the bones and sinews pertained to earth.

The four qualities of matter—hot, cold, moist and dry—were indicative of the presence of the four elements. Fire was the source of heat, air of cold, water of moisture, and earth of dryness. Between them, the four elements made up the unqualified being called Matter. All animals and other compound natures on earth had in them representatives of the four great physical constituents of the universe, but the moon, according to Chrysippus, consisted only of fire and air, while the sun was pure fire.

While all compound bodies were resolvable into the four elements, there were important differences among the elements, themselves. Two of them, fire and air, were light; the other two, water and earth, were heavy. By 'light' was meant that which tends away from its own centre, by 'heavy,' that which, tends towards it. The two light elements stood to the two heavy ones in much the same relation as the active to the passive principle generally. But further, fire had such a primary as entitles it, if the definition of element were pressed, to be considered alone worthy of the name. For the three other elements arose out of it and were to be again resolved into it.

We should obtain a wholly wrong impression of what Bishop Berkeley calls 'the philosophy of fire' if we set before our minds in this connection, the raging element whose strength is in destruction. Let us rather picture to ourselves as the type of fire the benign and beatific solar heat, the quickener and fosterer of all terrestrial life. For according to Zeno, there were two kinds of fire, the one destructive, the other what we may call 'constructive,' and which he called 'artistic'. This latter kind of fire, which was known as aether, was the substance of the heavenly bodies, as it was also of the soul of animals and of the 'nature' of plants. Chrysippus, following Heraclitus, taught that the elements passed into one another by a process of condensation and rarefaction. Fire first became solidified into air, then air into water and lastly water into earth. The process of dissolution took place in the reverse order, earth being rarefied into water, water into air, and air into fire. It is allowable to see in this old world doctrine an anticipation of the modern idea of different states of matter—the solid, the liquid, and the gaseous, with a fourth beyond the gaseous which science can still only guess at, and in which matter seems almost to merge into spirit.

Each of the four elements had its own abode in the universe. Outermost of all was the ethereal 'fire' which was divided into two spheres: first that of the fixed stars and next that of the planets. Below this lay the sphere of 'air', below this again that of 'water', and lowest or in other words, most central of all was the sphere of 'earth', the solid foundation of the whole structure. Water might be said to be above earth because nowhere was there water to be found without earth beneath it, but the surface of water was always equidistant from the centre, whereas earth had prominences which rose above water.

When we say that the Stoics regarded the universe as a plenum, the reader must understand by 'the universe' the Cosmos or ordered whole. Within this there was no emptiness owing to the pressure of the celestial upon the terrestrial sphere. But outside of this lay the infinite void without beginning, middle, or end. This occupied a very ambiguous position In their scheme. It was not being, for being was confined to body and yet it was there. It was in fact nothing, and that was why it was infinite. For as nothing cannot be bound to any thing, so neither can there be any bound to nothing. But while bodiless itself, it had the capacity to contain body, a fact which enabled it, despite its non-entity, to serve, as we shall see, a useful purpose.

Did the Stoics then regard the universe as finite or as infinite? In answering this question we must distinguish our terms, as they did. The All, they said, was infinite, but the Whole was finite. For the 'All' was the cosmos and the void, whereas the 'Whole' was the cosmos only. This distinction we may suppose to have originated with the later members of the school. For Appolodorus noted the ambiguity of the word 'All' as meaning,

(1) the cosmos only,
(2) cosmos + void

If then by the term "universe" we understand the cosmos, or ordered whole, we must say that the Stoics regarded the universe as finite. All being and all body, which was the same thing with being, had necessarily bounds, it was only not being, which was boundless.

Another distinction, due this time to Chrysippus himself, which the Stoics found it convenient to draw, was between the three words 'void,' 'place' and 'space'. Void was defined as 'the absence of body', place was that which was occupied by body, the term 'space' was reserved for that which was partly occupied and partly unoccupied. As there was no corner of the cosmos unfilled by body, space, it will be seen, was another name for the All. Place was compared to a vessel that was full, void to one that was empty, and space to the vast wine-cask, such as that in which Diogenes made his home, which was kept partly fully, but in which there was always room for more. The last comparison must of course not be pressed. For if space be a cask, it is one without top, bottom or sides.

But while the Stoics regarded our universe as an island of being in an ocean of void, they did not admit the possibility that other such islands might exist beyond our ken. The spectacle of the starry heavens, which presented itself nightly to their gaze in all the brilliancy of a southern sky—that was all there was of being, beyond that lay nothingness. Democritus or the Epicureans might dream of other worlds, but the Stoics contended for the unity of the cosmos as staunchly as the Mahometans for the unity of God, for with them the cosmos was God.

In shape they conceived of it as spherical, on the ground that the sphere was the perfect figure and was also the best adapted for motion. Not that the universe as a whole moved. The earth lay in its centre, spherical and motionless, and round it coursed the sun, moon, and planets, fixed each in its respective sphere as in so many concentric rings, while the outermost ring of all, which contained the fixed stars, wheeled round the rest with an inconceivable velocity.

The tendency of all things in the universe to the centre kept the earth fixed in the middle as being subject to an equal pressure on every side. The same cause also, according to Zeno, kept the universe itself at rest in the void. But in an infinite void, it could make no difference whether the whole were at rest or in motion. It may have been a desire to escape the notion of a migratory whole which led Zeno to broach the curious doctrine that the universe has no weight, as being composed of elements whereof two are heavy and two are light. Air and fire did indeed tend to the centre like everything else in the cosmos, but not till they had reached their natural home. Till then they were of an upward-growing nature. It appears then that the upward and downward tendencies of the elements were held to neutralise one another and to leave the universe devoid of weight.

The universe was the only thing which was perfect in itself, the one thing which was an end in itself. All other things were perfect indeed as parts, when considered with reference to the whole, but were none of them ends in themselves, unless man could be deemed so who was born to contemplate the universe and imitate its perfections. Thus, then, did the Stoics envisage the universe on its physical side—as one, finite, fixed in space, but revolving round its own centre, earth, beautiful beyond all things, and perfect as a whole.

But it was impossible for this order and beauty to exist without mind. The universe was pervaded by intelligence as man's body is pervaded by his soul. But as the human soul though everywhere present in the body is not present everywhere in the same degree, so it was with the world-soul. The human soul presents itself not only as intellect, but also in the lower manifestations of sense, growth, and cohesion. It is the soul which is the cause of the plant life, which displays itself more particularly in the nails and hair; it is the soul also which causes cohesion among the parts of the solid substances such as bones and sinews, that make up our frame. In the same way the world-soul displayed itself in rational beings as intellect, in the lower animals as mere souls, in plants as nature or growth, and in inorganic substances as 'holding' or cohesion. To this lowest stage add change, and you have growth or plant nature; super-add to this phantasy and impulse and you rise to the soul of irrational animals; at a yet higher stage you reach the rational and discursive intellect, which is peculiar to man among mortal natures.

We have spoken of soul as the cause of the plant life in our bodies, but plants were not admitted by the Stoics to be possessed of soul in the strict sense. What animated them was 'nature' or, as we have called it above, 'growth'. Nature, in this sense of the principle of growth, was defined by the Stoics as 'a constructive fire, proceeding in a regular way to production,' or 'a fiery spirit endowed with artistic skill'. That Nature was an artist needed no proof, since it was her handiwork that human art essayed to copy. But she was an artist who combined the useful with the pleasant, aiming at once at beauty and convenience. In the widest sense, Nature was another name for Providence, or the principle which held the universe together, but, as the term is now being employed, it stood for that degree of existence which is above cohesion and below soul. From this point of view, it was defined as "a cohesion subject to self originated change in accordance with seminal reasons effecting and maintaining its results in definite times, and reproducing in the offspring the characteristics of the parent". This sounds about as abstract as Herbert Spencer's definition of life, but it must be borne in mind that nature was all the time a 'spirit', and as such a body. It was a body of a less subtle essence than soul. Similarly, when the Stoics spoke of cohesion, they are not to be taken as referring to some abstract principle like attraction. 'Cohesions,' said Chrysippus, 'are nothing else than airs, for it is by these that bodies are held together, and of the individual qualities of things which are held together by cohesion, it is the air which is the compressing cause which in iron is called "hardness", in stone "thickness" and in solver "whiteness"'. Not only solidarity then, but also colours, which Zeno called 'the first schematisms' of matter were regarded as due to the mysterious agency of air. In fact, qualities in general were but blasts and tensions of the air, which gave form and figure to the inert matter underlying them.

As the man is in one sense the soul, in another the body, and in a third the union of both, so it was with the cosmos. The word was used in three senses—

(1) God
(2) the arrangement of the stars, etc.
(3) the combination of both.

The cosmos as identical with God was described as an individual made up of all being who is incorruptible and ungenerated, the fashioner of the ordered frame of the universe, who at certain periods of time absorbs all being into himself and again generates it from himself. Thus the cosmos on its external side was doomed to perish and the mode of its destruction was to be by fire, a doctrine which has been stamped upon the world's belief down to the present day. What was to bring about this consummation was the soul of the universe becoming too big for its body, which it would eventually swallow up altogether. In the efflagration, when everything went back to the primeval aether, the universe would be pure soul and alive equally through and through. In this subtle and attenuated state, it would require more room than before and so expand into the void, contracting again when another period of cosmic generation had set in. Hence the Stoic definition of the Void or Infinite as that into which the cosmos is resolved at the efflagration.

In this theory of the contraction of the universe out of an ethereal state and ultimate return to the same condition one sees a resemblance to the modern scientific hypothesis of the origin of our planetary system out of the solar nebula, and its predestined end in the same. Especially is this the case with the form in which the theory was held by Cleanthes, who pictured the heavenly bodies as hastening to their own destruction by dashing themselves, like so many gigantic moths, into the sun. Cleanthes however did not conceive mere mechanical force to be at work in this matter. The grand apotheosis of suicide which he foresaw was a voluntary act; for the heavenly bodies were Gods and were willing to lose their own in a larger life.

Thus all the deities except Zeus were mortal, or at all events, perishable. Gods, like men, were destined to have an end some day. They would melt in the great furnace of being as though they were made of wax or tin. Zeus then would be left alone with his own thoughts, or as the Stoics sometimes put it, Zeus would fall back upon Providence. For by Providence they meant the leading principle or mind of the whole, and by Zeus, as distinguished from Providence, this mind together with the cosmos, which was to it as body. In the efflagration the two would be fused into one in the single substance of aether. And then in the fulness of time there would be a restitution of all things. Everything would come round regularly again exactly as it had been before.

To us who have been taught to pant for progress, this seems a dreary prospect. But the Stoics were consistent Optimists, and did not ask for a change in what was best. They were content that the one drama of existence should enjoy a perpetual run without perhaps too nice a consideration for the actors. Death intermitted life, but did not end it. For the candle of life, which was extinguished now, would be kindled again hereafter. Being and not being came round in endless succession for all save him, into whom all being was resolved, and out of whom it emerged again, as from the vortex of some aeonian Maelstrom.