Guide for the Perplexed, by Moses Maimonides, Friedländer tr. [1904], at sacred-texts.com
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
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.