REFUTATION OF AVICEBRON'S POSITION
24.--These arguments which we have set forth are plainly improbable in many respects:
The first argument is unacceptable because Avicebron proceeds upward from the lower beings to the highest ones by resolving them into material principles, which is an argument absolutely contrary to reason. For matter is compared to form as potency to act. Now it is clear that potency is less a being than is act, for potency is said to be a being only according to its order to act. Wherefore, neither do we say without qualification that the things which are in potency exist; we say this only of things which are in act. Therefore, the lower one descends by resolving to material principles, the less does one find of the character of being. On the other hand, among beings the highest ones must be preeminently beings, for the highest in every genus which are the principles of all the rest, are eminently said to exist in the highest degree, just as fire is most hot. Accordingly, Plato, while investigating the highest beings, proceeded by resolving them into formal principles, as has been said above. Most unfittingly therefore, did Avicebron proceed in the opposite direction by resolving beings into material principles.
25.--Second, because at least so far as appears from his own words, Avicebron in a way returned to the opinion of the ancient Naturalists who held that all things were one being, by positing that the substance of all things was nothing other than matter. This matter they did not consider as something only in potency, as Plato and Aristotle did, but as some actual being. There was this difference, however, that the ancient Naturalists, believing that only bodies existed, said that this common matter and substance of all things was some body, as for example, fire or air or water or something in between; on the other hand, Avicebron, thinking that the nature of things was not contained in bodies alone, said that that one principle which he held to be the first matter and common substance of all things, was a non-corporeal substance. And that he posited this universal matter, which he says is the substance of all things, in the same way in which the Naturalists posited this of some one body, is clear from the fact that according to Avicebron, matter is the genus of those things which agree in genus, while the differences by which the species differ, are forms.
26.--For he says that the common matter of all material things is body itself. And again, the common matter of all substances, both corporeal and spiritual, is substance itself. Therefore it is clear that there is the same relation of the genus to its differences as of a subject to its proper attributes. In other words, substance is divided into spiritual and corporeal, and body into heavenly and elemental, just as number is divided into odd and even, and animal into healthy and sick. Of these, number is the subject of the even and of the odd as of its proper attributes, and animal is the subject of the healthy and the sick, with the subject and the attributes being predicated of all the species. Thus, therefore, if the substance that is predicated of all things, should be compared to spiritual and corporeal as the matter which is their subject, it will follow that these two come to substance in the manner of accidental attributes. The same applies in all subsequent cases, as he himself expressly admits by positing that all forms considered in themselves are accidents. They are said to be, however, "substantial", in comparison with certain things in whose definitions they are included, as whiteness belongs to the definition of a white man.
27.--But this position destroys the true nature of prime matter. For if it is of the nature of matter that it be in potency, then prime matter must be completely in potency. As a consequence, it is not predicated of any actually existing thing, just as a part is not predicated of the whole. This position likewise destroys the principles of logic by doing away with the true nature of genus, species, and substantial difference, inasmuch as it reduces them all to the mode of accidental predication. Moreover, it destroys the foundations of natural philosophy by removing a true generation and corruption from things, as did the ancient Naturalists, in positing one material principle. For a thing is said without qualification to be generated only because it becomes without qualification a being. For nothing which previously existed comes to be. Therefore if it existed previously in act--which is for it without qualification to exist--it will follow that it will not unqualifiedly become a being but rather a being which previously was not. Therefore, it will be generated in a certain respect and not in an unqualified manner.
28.--Finally and to reach a last conclusion, the aforementioned position also destroys the principles of first philosophy by taking away unity from each thing and, as a consequence, the true being and the diversity of things. For if to some being existing in act, another act is added, the whole will not be one essentially but only accidentally because two acts or forms are essentially diverse and agree only in subject. But to be one through the unity of the subject is to be one accidentally, whether the two forms are not ordered to each other, as the white and the musical, (for we say that the white and the musical are one accidentally because they inhere in one subject), or whether the forms or the acts are ordered to one another as color and surface. For that which is colored and has a surface is not absolutely one, though in a way, the "colored" is essentially predicated of the surfaced thing, not indeed, because "surfaced" signifies the essence of the "colored", as genus signifies the essence of a species, but because the subject is included in the definition of an accident; or otherwise the "colored" would not be predicated of the surfaced thing essentially but the "surfaced" of the "colored".
Now in this way alone is a species one without qualification, namely, insofar as that which is man is truly animal, not because animal is the subject of the form man but because the very form animal is the form man, differing only as the indeterminate from the determinate. For, if animal be one thing and biped something else, the biped animal that is man will not be essentially one and consequently will not be essentially a being. As a consequence, it follows that whatever things agree in the genus, will differ only by an accidental difference and all things will be one in substance which is the genus and the subject of all substances; just as the one part of a surface is white and the other part black, yet the whole is one surface. For this reason, the ancients themselves who posited one matter which was the substance of all things and predicated of all of them, asserted that all things were one. These difficulties likewise beset those who posit an order of diverse substantial forms in one and the same being.
29.--Third, following the method of the aforementioned position, it is necessary to proceed to infinity among material causes, with the result that a first matter is never reached. For in all things which agree in some point and differ in another, that in which they agree, they have as their matter; and that in which they differ, they have as their form, as is clear from what has been said. If, therefore, there is one common matter for all things for it to receive diverse forms, it is then necessary that the more noble form should be received in a finer and more excellent matter; the less noble form should be received in an inferior and coarser matter; for example, the form of spirituality should be received in a more refined matter, whereas the form of corporeity should be received in an inferior matter, as he himself says. Prior to the form of spirituality and of corporeity, there is therefore required in matter a difference of fineness and coarseness. It is therefore again necessary that prior to the coarseness and fineness, there pre-exist in matter some other difference through which one matter is receptive of the one and the other receptive of the other. The same question will re-appear concerning those other pre-existent differences and so on to infinity. For as often as one arrived at one completely uniform matter, according to the principles of the aforementioned position it would be necessary that this matter should receive only one form and this equally throughout the whole. And again the matter underlying that form would, as a consequence, receive only one form and this uniformly throughout the whole; and thus by descending even to the lowest of beings, no diversity could be found in things.
30.--Fourth, given the position of the ancient Naturalists that there was a prime matter as the common substance of all things, it was possible to produce diverse things from it by attributing diverse forms to diverse parts of this common substance. For, since that common matter was corporeal, there could be understood in it a division according to quantity. But if we remove quantitative division, there remains only a division according to form or according to matter. If, therefore, we posit a universal matter which is common to every substance and which has no quantity in its nature, the division of this matter can be understood only according to form or only according to the matter itself.
When, however, it is said that common incorporeal matter in part receives this form and in part that form, a division of matter is presupposed to the diversity of the forms received in the matter. That division, therefore, cannot be understood according to some other forms. If, therefore, it should be understood according to some forms, it must be understood according to prior forms of which matter receives neither one through the whole of itself. Accordingly, it is necessary again that we presuppose in matter some sort of division or distinction. This distinction or division, too, will therefore be according to other forms to infinity, or we must come to this, that the first division is according to the matter itself.
31.--Now there cannot be a division according to matter except because the matter is distinguished through itself and not through a diverse disposition or form or quantity; for this would mean that the matter is distinguished according to quantity or form or disposition. Therefore we must finally reach the conclusion that there is not one matter for all things but that matters are many and distinct in themselves. Now it is proper for matter to be in potency. This distinction of matter must therefore not be understood according as matter contains its diverse forms or dispositions, for this is outside the essence of matter, but according to the distinctions of potency with respect to the diversity of forms. For, since potency is called that which is said relatively to act, it is necessary that potency be distinguished with respect to that of which potency is primarily predicated. I say potency is primarily said in relation to something in the manner in which the potency to see is said in relation to color but not to white and black, since the same potency can receive both. In the same way, a surface can receive white and black according to one potency which is primarily predicated with respect to color. Avicebron therefore presupposed a clearly false principle when he said that potency and reception are found in all in the same way.