Coming to Know Ens Commune – Negative Judgment
What defines the science of metaphysics is its subject matter, and according to Aquinas, the subject matter of metaphysics is ens commune, i.e. common being. But ens commune, as explained elsewhere, enjoys what Thomists have come to term a negative immateriality. It does not carry with it the notion of a positive immateriality, i.e. the notion of positively being without matter as, e.g. God or angels are non-material in a positive sense. The immateriality of common being is such that common being is know to be realized in material things, but that it need not be so realized. It is immaterial in the sense of an exclusive association with matter is denied of it (hence the term negative). However, if one is to know that common being does not have an exclusive association with material things, one has to know that being has an association with some non-material kind of thing. Thus, in order to establish the subject matter of metaphysics, one has first to establish scientifically the existence of immaterial realities. And, since the knowledge of this association is supposed to take place when one is beginning his or her study of the science, such knowledge must be gained in a prior science, i.e. the science of the philosophy of nature.
There are traditionally two kinds of positively immaterial things that one comes to know prior to Thomistic metaphysics. A philosopher of nature can come to know of the positively immaterial if, by investigating the human soul and the nature of understanding, she can demonstrate that the principle of human life, i.e. the soul, is also immaterial. Likewise, the natural philosopher is able make an intelligible claim about the existence of a positively immaterial subsistent thing if and only if he can, for example, by the reasoning proper to his science, make a true predication that the substance which is the First Mover is not material.
This latter possibility is just what is realized at the end of Aquinas’ commentary on the Physics of Aristotle according to those who claim that proof of an immaterial subsistent is necessary to initiate metaphysics.(Mark Johnson, “Immateriality and the Domain of Thomistic Natural Philosophy,” Modern Schoolman, 67 (1990), p. 300.)
And so it is clear that the prime mover is indivisible, both because it has no part, just as the point is also indivisible, and also as having no magnitude whatsoever, existing as it were outside the genus of magnitude. And in this way the Philosopher terminates the common consideration of natural things in the first principle of the whole of nature, who is God, above all Blessed forever, Amen.Thomas Aquinas, Commentary on Aristotle’s Physics, Book VIII, l. 23, n. 1172, as cited by Johnson.
Mark F. Johnson comments: It bears stressing that the ‘this way’ mentioned by Thomas is that of natural philosophy…. Now the middle term in the argument that precedes this corollary is ‘partless mover of infinite power,’ and the condition of the prime mover such that it be said to be ‘of infinite power’ and ‘partless’ was shown to be true through arguments that fall within the domain of natural philosophy: continuous sempiternal motion, and the impossibility of such a mover’s residing in a body of finite magnitude — a body of infinite magnitude has already been ruled out….(emphasis mine)
This demonstration leaves us with an immaterial being of infinite power, and Thomas takes this to be God, although an angel would seem a possible per se existing immaterial reality capable of being the prime mover of the motions of material things.Johnson, “Immateriality and the Domain …,” p. 300-301.
The philosopher of nature can come to know the existence of a positively immaterial subsistent things if, and only if, he can, by the reasoning proper to his science, make a true predication of such a kind that commits him, on the one hand, to denying of a hypothetical subject predicates that characterize material things. This feat is within the competence of his science of material things. On the other hand, his science must also lead him to affirming predicates that commit that hypothetical subject of having the being that belongs to substance. In this way, the natural philosopher’s concept of substance, previously limited to the material order, is seen to extend beyond the material.
For example, if the statement “The Prime Mover is immaterial” is known to be true, then the philosopher of nature begins by using “is” to signify the truth of the predication. Since “immaterial” means “partless mover of infinite power” it commits the natural philosopher to extending to the Prime Mover being in the sense of substance. And since the being of substance is seen to apply to something that is not a body, it is seen that not all being is material.
It is possible to make true predications about the immaterial within the philosophy of nature since it is within the competence of a science to know whether a thing falls outside of its field of inquiry. And if the philosopher of nature can draw the true conclusion, for example, that the First Mover to which his science naturally tends is both subsistent and not material, then he knows that not all being is material.
Such an assertion provides a basis for grasping the formality ens inquantum ens, or ens commune, which designates the subject of metaphysics, as negatively immaterial. This assertion allows one to grasp being as being in contradistinction to materiality because it shows that to be is not the same as to be material. If a natural philosopher has actually demonstrated a subsistent immaterial thing, then he has accomplished what will allow him to initiate the subject of metaphysics using pre-metaphysical means.
If it is to be required that metaphysics begin with the knowledge that its subject matter is distinct from natural philosophy’s, then natural philosophy’s proof for the immaterial seems essential. For if, and only if, one can say that there is some being which is not material, is it possible to claim that not all being is material and that being is separate from materiality. Unless one knows that there is some immaterial reality, one will not know that “to be” is distinct from “to be made of stuff.”
This, then, is the subject of metaphysics, common being or being as such. The meaning of common being must then be refined to make it a suitable topic for human inquiry, that is, to establish the proper subject matter of metaphysics. This the metaphysician does by making a negative judgment about being.
The negative judgment, “being is neither material nor immaterial exclusively,” is the only way for human understanding to establish the subject matter of metaphysics. Common being first of all cannot be abstracted from material things, the mode of understanding to which the human mind is most properly proportioned. Abstraction is made from material things. Consequently it gives not the slightest awareness of immaterial being. More importantly, the essence of the material comes to the knower through abstraction, leaving behind its particular existence, the very notion we are trying to formulate. Instead, being is known through a judgment including both materiality and immateriality. This judgment is not a positive one for immateriality is not known positively. Being, then, is known through separation from any exclusive association with the material or immaterial.
In order to study common being, we apply it to both material and immaterial beings analogously and not univocally. From this negative judgment, the metaphysician may gather that there are two ways for things to exist, as opposed to two kinds of things that exist in just one way. The being of a thing is related to the kind of thing that it is; such that material beings exist materially, and immaterial beings exist immaterially. Common being is the analogous proper proportionality between an essence and its existence, according to its corporeality, or lack thereof.