We.—Is the substance of the surrounding sphere, i.e., the heavens, the same as that of the elements?
Ar.—No; the substance is different, and the forms are different. The term “body” is homonymously used of these bodies below and of the heavens, as has been shown by modern philosophers. All this has been demonstrated by proof.
But let now the reader of this treatise hear what I have to say. Aristotle has proved that the difference of forms becomes evident by the difference of actions. Since, therefore, the motion of the elements is rectilinear, and that of the spheres circular, we infer that the substances are different. This inference is supported by Natural Science. When we further notice that substances with rectilinear motion differ in their directions, that some move upward, some downward, and that substances which move in the same direction have different velocities, we infer that their forms must be different. [[186]]Thus we learn that there are four elements. In the same way we come to the conclusion that the substance of all the spheres is the same, since they all have circular motion. Their forms, however, are different, since one sphere moves from east to west, and another from west to east; and their motions have also different velocities. We can now put the following question to Aristotle: There is one substance common to all spheres; each one has its own peculiar form. Who thus determined and predisposed these spheres to receive different forms? Is there above the spheres any being capable of determining this except God? I will show the profundity and the extraordinary acumen which Aristotle displayed when this question troubled him. He strove very hard to meet this objection with arguments, which, however, were not borne out by facts. Although he does not mention this objection, it is clear from his words that he endeavours to show the nature of the spheres, as he has shown that of the things in the sublunary world. Everything is, according to him, the result of a law of Nature, and not the result of the design of a being that designs as it likes, or the determination of a being that determines as it pleases. He has not carried out the idea consistently, and it will never be done. He tries indeed to find the cause why the sphere moves from east and not from west; why some spheres move with greater velocity, others with less velocity, and he finds the cause of these differences in their different positions in reference to the uppermost sphere. He further attempts to show why there are several spheres for each of the seven planets, while there is only one sphere for the large number of fixed stars. For all this he endeavours to state the reason, so as to show that the whole order is the necessary result of the laws of Nature. He has not attained his object. For as regards the things in the sublunary world, his explanations are in accordance with facts, and the relation between cause and effect is clearly shown. It can therefore be assumed that everything is the necessary result of the motions and influences of the spheres. But when he treats of the properties of the spheres, he does not clearly show the causal relation, nor does he explain the phenomena in that systematic way which the hypothesis of natural laws would demand. For let us consider the spheres: in one case a sphere with greater velocity is above a sphere with less velocity, in another case we notice the reverse; in a third case there are two spheres with equal velocities, one above the other. There are, besides, other phenomena which speak strongly against the hypothesis that all is regulated by the laws of Nature, and I will devote a special chapter to the discussion of these phenomena. In short, there is no doubt that Aristotle knew the weakness of his arguments in tracing and describing the cause of all these things, and therefore he prefaces his researches on these things as follows:—“We will now thoroughly investigate two problems, which it is our proper duty to investigate and to discuss according to our capacity, wisdom, and opinion. This our attempt must not be attributed to presumption and pride, but to our extraordinary zeal in the study of philosophy; when we attempt the highest and grandest problems, and endeavour to offer some proper solution, every one that hears it should rejoice and be pleased.” So far Aristotle. This shows that he undoubtedly knew the weakness of his theory. How much weaker must it appear when we bear in mind that the science of Astronomy was not yet fully developed, and that in the days of Aristotle the motions of the [[187]]spheres were not known so well as they are at present. I think that it was the object of Aristotle in attributing in his Metaphysics one Intelligence to every sphere, to assume the existence of something capable of determining the peculiar course of each sphere. Later on I will show that he has not gained anything thereby; but now I will explain the words, “according to our capacity, wisdom, and opinion,” occurring in the passage which we quoted. I have not noticed that any of the commentators explain them. The term “our opinion” refers to the principle that everything is the result of natural laws, or to the theory of the Eternity of the Universe. By “our wisdom” he meant the knowledge of that which is clear and generally accepted, viz., that the existence of every one of these things is due to a certain cause, and not to chance. By “our capacity” he meant the insufficiency of our intellect to find the causes of all these things. He only intended to trace the causes for a few of them; and so he did. For he gives an excellent reason why the sphere of the fixed stars moves slowly, while the other spheres move with greater velocity, namely, because its motion is in a different direction [from the uppermost sphere]. He further says that the more distant a sphere is from the eighth sphere the greater is its velocity. But this rule does not hold good in all cases, as I have already explained (p. 174). More forcible still is the following objection: There are spheres below the eighth that move from east to west. Of these each upper one, according to this rule, would have a greater velocity than the lower one; and the velocity of these spheres would almost equal that of the ninth sphere. But Astronomy had, in the days of Aristotle, not yet developed to the height it has reached at present.
According to our theory of the Creation, all this can easily be explained; for we say that there is a being that determines the direction and the velocity of the motion of each sphere; but we do not know the reason why the wisdom of that being gave to each sphere its peculiar property. If Aristotle had been able to state the cause of the difference in the motion of the spheres, and show that it corresponded as he thought to their relative positions, this would have been excellent, and the variety in their motions would be explained in the same way as the variety of the elements, by their relative position between the centre and the surface; but this is not the case, as I said before.
There is a phenomenon in the spheres which more clearly shows the existence of voluntary determination; it cannot be explained otherwise than by assuming that some being designed it: this phenomenon is the existence of the stars. The fact that the sphere is constantly in motion, while the stars remain stationary, indicates that the substance of the stars is different from that of the spheres. Abu-nasr has already mentioned the fact in his additions to the Physics of Aristotle. He says: “There is a difference between the stars and the spheres; for the spheres are transparent, the stars are opaque; and the cause of this is that there is a difference, however small it may be, between their substances and forms.” So far Abu-nasr. But I do not say that there is a small difference, but a very great difference; because I do not infer it from the transparency of the spheres, but from their motions. I am convinced that there are three different kinds of substance, with three different forms, namely:—(1) Bodies which never move of their own accord; such are [[188]]the bodies of the stars; (2) bodies which always move, such are the bodies of the spheres; (3) bodies which both move and rest, such are the elements. Now, I ask, what has united these two bodies, which, according to my opinion, differ very much from each other, though, according to Abu-nasr, only a little? Who has prepared the bodies for this union? In short, it would be strange that, without the existence of design, one of two different bodies should be joined to the other in such a manner that it is fixed to it in a certain place but does not combine with it. It is still more difficult to explain the existence of the numerous stars in the eighth sphere; they are all spherical; some of them are large, some small; here we notice two stars apparently distant from each other one cubit; there a group of ten close together; whilst in another place there is a large space without any star. What determined that the one small part should have ten stars, and the other portion should be without any star? and the whole body of the sphere being uniform throughout, why should a particular star occupy the one place and not another? The answer to these and similar questions is very difficult, and almost impossible, if we assume that all emanates from God as the necessary result of certain permanent laws, as Aristotle holds. But if we assume that all this is the result of design, there is nothing strange or improbable; and the only question to be asked is this: What is the cause of this design? The answer to this question is that all this has been made for a certain purpose, though we do not know it; there is nothing that is done in vain, or by chance. It is well known that the veins and nerves of an individual dog or ass are not the result of chance; their magnitude is not determined by chance; nor is it by chance, but for a certain purpose, that one vein is thick, another thin; that one nerve has many branches, another has none; that one goes down straight, whilst another is bent; it is well known that all this must be just as it is. How, then, can any reasonable person imagine that the position, magnitude, and number of the stars, or the various courses of their spheres, are purposeless, or the result of chance? There is no doubt that every one of these things is necessary and in accordance with a certain design; and it is extremely improbable that these things should be the necessary result of natural laws, and not that of design.
The best proof for design in the Universe I find in the different motions of the spheres, and in the fixed position of the stars in the spheres. For this reason you find all the prophets point to the spheres and stars when they want to prove that there must exist a Divine Being. Thus Abraham reflected on the stars, as is well known; Isaiah (xl. 26) exhorts to learn from them the existence of God, and says, “Lift up your eyes on high, and behold who hath created these things?” Jeremiah [calls God] “The Maker of the heavens”; Abraham calls Him “The God of the heavens” (Gen. xxiv. 7); [Moses], the chief of the Prophets, uses the phrase explained by us (Part I., chap, lxx.), “He who rideth on the heavens” (Deut. xxxiii. 26). The proof taken from the heavens is convincing; for the variety of things in the sublunary world, though their substance is one and the same, can be explained as the work of the influences of the spheres, or the result of the variety in the position of the substance in relation to the spheres, as has been shown by Aristotle. But who has determined the variety in the spheres and the stars, if not the Will of God? To say that the Intelligences have determined it [[189]]is of no use whatever; for the Intelligences are not corporeal, and have no local relation to the spheres. Why then should the one sphere in its desire to approach the Intelligence, move eastward, and another westward? Is the one Intelligence in the east, the other in the west? or why does one move with great velocity, another slowly? This difference is not in accordance with their distances from each other, as is well known. We must then say that the nature and essence of each sphere necessitated its motion in a certain direction, and in a certain manner, as the consequence of its desire to approach its Intelligence. Aristotle clearly expresses this opinion. We thus have returned to the part from which we started; and we ask, Since the substance of all things is the same, what made the nature of one portion different from another? Why has this sphere a desire which produces a motion different from that which the desire of another sphere produces? This must have been done by an agent capable of determining. We have thus been brought to examine two questions:—(1) Is it necessary to assume that the variety of the things in the Universe is the result of Design, and not of fixed laws of Nature, or is it not necessary? (2) Assuming that all this is the result of Design, does it follow that it has been created after not having existed, or does Creatio ex nihilo not follow, and has the Being which has determined all this done always so? Some of those who believe in the Eternity of the Universe hold the last opinion. I will now begin the examination of these two questions, and explain them as much as necessary in the following chapters.
CHAPTER XX
According to Aristotle, none of the products of Nature are due to chance. His proof is this: That which is due to chance does not reappear constantly nor frequently, but all products of Nature reappear either constantly or at least frequently. The heavens, with all that they contain, are constant; they never change, as has been explained, neither as regards their essence nor as regards their place. But in the sublunary world we find both things which are constant and things which reappear frequently [though not constantly]. Thus, e.g., the heat of fire and the downward tendency of a stone are constant properties, whilst the form and life of the individuals in each species are the same in most cases. All this is clear. If the parts of the Universe are not accidental, how can the whole Universe be considered as the result of chance? Therefore the existence of the Universe is not due to chance. The following is, in short, the objection which Aristotle raises against one of the earlier philosophers who assumed that the Universe is the result of chance, and that it came into existence by itself, without any cause. Some assume that the heavens and the whole Universe came into existence spontaneously, as well as the rotation and motion [of the spheres], which has produced the variety of things and established their present order. This opinion implies a great absurdity. They admit that animals and plants do not owe their existence or production to chance, but to a certain cause, be that cause Nature, or reason, or the like; e.g., they do not assume that everything might be formed by chance of a certain seed or semen, but that of a certain seed only an olive-tree is produced, and of a certain semen only [[190]]a human being is developed. And yet they think that the heavens, and those bodies which appear divine among the rest of bodies, came into existence spontaneously, without the action of any such cause as produces plants and animals. Having thus examined this theory, Aristotle then proceeds to refute it at greater length. It is therefore clear that Aristotle believes and proves that things in real existence are not accidental; they cannot be accidental, because they are essential, i.e., there is a cause which necessitates that they should be in their actual condition, and on account of that cause they are just as they in reality are. This has been proved, and it is the opinion of Aristotle. But I do not think that, according to Aristotle, the rejection of the spontaneous origin of things implies the admission of Design and Will. For as it is impossible to reconcile two opposites, so it is impossible to reconcile the two theories, that of necessary existence by causality, and that of Creation by the desire and will of a Creator. For the necessary existence assumed by Aristotle must be understood in this sense, that for everything that is not the product of work there must be a certain cause that produces it with its properties; for this cause there is another cause, and for the second a third, and so on. The series of causes ends with the Prime Cause, from which everything derives existence, since it is impossible that the series should continue ad infinitum. He nevertheless does not mean to say that the existence of the Universe is the necessary product of the Creator, i.e., the Prime Cause, in the same manner as the shadow is caused by a body, or heat by fire, or light by the sun. Only those who do not comprehend his words attribute such ideas to him. He uses here the term necessary in the same sense as we use the term when we say that the existence of the intellectus necessarily implies that of the intellectum, for the former is the efficient cause of the latter in so far as intellectum. Even Aristotle holds that the Prime Cause is the highest and most perfect Intellect; he therefore says that the First Cause is pleased, satisfied, and delighted with that which necessarily derives existence from Him, and it is impossible that He should wish it to be different. But we do not call this “design,” and it has nothing in common with design. E.g., man is pleased, satisfied, and delighted that he is endowed with eyes and hands, and it is impossible that he should desire it to be otherwise, and yet the eyes and hands which a man has are not the result of his design, and it is not by his own determination that he has certain properties and is able to perform certain actions. The notion of design and determination applies only to things not yet in existence, when there is still the possibility of their being in accordance with the design or not. I do not know whether the modern Aristotelians understood his words to imply that the existence of the Universe presupposes some cause in the sense of design and determination, or whether, in opposition to him, they assumed design and determination, in the belief that this does not conflict with the theory of the Eternity of the Universe.
Having explained this, I will now proceed to examine the opinions of the modern philosophers.