2. Inasmuch as the actuality of a given essence makes a given thing formally complete, one, and perfect according to its entitative degree, it is to such an actuality that everything owes that it is formally good, and that it answers to the finality of its creation. Such a goodness implies two things: the first, that every creature is good in its absolute being, for it is in such a being that God's design is fulfilled of communicating his goodness outside of himself; the other, that every creature is good in its relative being also—that is, in its intrinsic aptitude and determination to manifest God's perfections in a manner and degree proportionate to the kind and degree of its entity. Accordingly, every created being is good not only as it is a thing, but also as it is a principle of action. In the first capacity it fulfils the immediate end of its creation, and in the second it fulfils by its action the ultimate end for the sake of which it has been made to exist.
3. Hence we further infer, that the essence of every created being is its nature also. For nature is a principle of motion, according to Aristotle, whether motion is taken as the action proceeding from that nature itself, or as the reception of an action proceeding from an extrinsic agent. Now, we have seen that all creatures are manifestative of God's perfections, and therefore that they have in themselves an act which is a principle of action; on the other hand, we have also seen that every creature has its potential term, and therefore passivity, or receptivity of new determinations. Accordingly, every created being, by the very nature of its essential constituents, is a complete principle of motion. Essence and nature are, therefore, the same thing in reality, though they are distinguished from one another in our conception. S. Thomas considers that these three words, nature, essence, and quiddity, apply to one and the same thing viewed under three distinct aspects; the word nature meaning the essence of the thing as connoting operation, since there is no natural being without active power; whereas the word quiddity means the same essence viewed as an object of definition; and the word essence is used to express the fact that in it and through it a thing has its own being.[286] Whence it follows that a complete being is no sooner endowed with existence than with activity, and is no sooner a being than an individual nature. And therefore a complete being and a concrete nature are really one and the same thing. Malebranche's theory, denying that creatures have any true causality, is therefore utterly untenable, as it cannot be reconciled with the first principles of metaphysics.
4. The entity of the active power contained in the nature of any being cannot be anything else than its essential act; that is, the very act produced by God in its creation. In fact, we have just seen that in all creatures the essence and the nature are the same reality, and that the constituents of the nature are nothing but the constituents of the essence. Accordingly, the nature of every creature consists of an essential act and an essential term; the one being its principle of activity, as the other is its principle of passivity. "The form," says S. Thomas, "is that by which the agent acts," and "By what a thing is, by that it acts," and "The principle of being is the principle of acting," and "Every agent acts inasmuch as it is in act." These axioms are accepted by all real philosophers. Hence the active principle of any complete being, and its essential act, are the same thing in reality, though they are distinguished from one another in our conception, in the same manner as are nature and essence; for the essential act connotes the intrinsic term of the essence, to which the act is essentially terminated, whilst the active principle connotes any extrinsic term to which the action proceeding from the same act is, or can be, accidentally terminated. This is what S. Thomas means when he says that "a natural form is a principle of operation, not inasmuch as it is the permanent form of the thing to which it gives existence, but inasmuch as it has a leaning towards an effect."[287] Such a leaning (inclinatio) should be taken to mean a natural ordination or determination to act.
Philosophers agitate the question, whether created substances act by themselves immediately, or by the aid of accidents. The Scotistic school holds the first opinion, whilst the Thomistic supports the second. For reasons which it would take too long to develop in this place, we are inclined to believe that natural accidents are not active, and that their bearing on the action of substance is not of an efficient, but of a formal, character; by which we mean that accidents have no play in the production of effects, except inasmuch as their presence or absence entails a different formal determination of the conditions in which the agent is to exert its power. It is true, indeed, that created substances never act independently of accidental conditions; but it is true, at the same time, that they always act by themselves without the aid of accidents, inasmuch as the active power they exert is so exclusively owned by them that it cannot even partially reside in any of their accidents.
As the active principle is really nothing else than the act by which the agent is, so also the passive principle is really nothing else than the essential term by which that act is completed. Here again the same reality presents itself under two distinct aspects; for the phrase essential term connotes the essential act by which the term is essentially actuated, whilst the phrase passive principle connotes any accidental act by which the same term is liable to be accidentally actuated.
5. Since a being possessing its three intrinsic principles is so fully and adequately constituted as to require nothing additional to exist, it is obvious that such a being contains in its perfect constitution the sufficient reason of its aptitude to exist non in alio et non per aliud, but in se et per se; that is, in itself and by itself. Now, to exist in itself is to be a substance, and to exist by itself is to be what philosophers call suppositum—i.e., a thing having separate subsistence; and, therefore, such a being, if simply left to itself, will be both a substance and a suppositum. In fact, the essential act of a created being, though always needing positive conservation on account of its contingency, needs no termination to, or sustentation from, a subject, as it already holds under itself its own intrinsic term, by which it is sufficiently terminated and sustained. And in the same manner, the essence of a complete being needs no union with any extraneous nature to be made completely subsistent, as it is already sufficiently complete on account of its formal actuality and individuality. Thus it is manifest that nothing positive is to be added to a complete being in order to make it a substance and a suppositum; it suffices to leave it alone without further sustentation and without further completion. By the first of these two negations, the being will exist non in alio, but in itself; and by the second it will subsist non per aliud, but by itself. Hence it is that the first negation is called the mode of substance, and the second the mode of the suppositum.
6. To be, to be true, to be one, to be good, to be a thing or a being, are convertible expressions so far as their real objective meaning is concerned, and are distinct only on account of their different connotations. A thing is called a being, inasmuch as it has existence. It is called true, inasmuch as its act suits its term, and vice versa. For the objective truth of things—i.e., their metaphysical truth—is nothing but their intelligibility; and the whole intelligibility of a being consists in the agreement of an essential act with its essential term; that is, in this: that the one adequately satisfies the wants of the other, and thus constitutes with it one perfect intelligible ratio or essence. Hence the termination of the proper act to the proper term makes a thing objectively true; just as the application of the proper predicate to the proper subject makes true a proposition. This objective or metaphysical truth is perfectly independent of our knowledge of it; it has, however, the reason of its being in God's intellect, in which the archetypes of all that is intelligible are contained, and to which the whole ideal order is to be traced as to its original source. A thing is called one on account of the formal unity of its essence and of its existence. It is called good, objectively and metaphysically, inasmuch as it is materially and formally complete in the manner above described, and consequently perfect, so as to require no further intrinsic endowment to exist.
The objective goodness of any being arises from its truth; for it is the mutual fitness of the essential act and of the essential term that accounts for their mutual agreement in unity of existence; whence it follows that the being will naturally exist in itself, and subsist by itself, without any further addition, as though finding rest in its own reality. But, that in which anything finds rest is its own good; and therefore everything that exists in itself completely is good to itself, while its act and its term, as the intrinsic factors of such a goodness, are good also, but only of an initial and relative goodness—viz., so far as the one is good to the other. Lastly, the word thing expresses the whole being as it is in its concrete essence—that is, the whole reality implied in its three intrinsic principles. Thing in Latin is res; and res, as well as ratio, are connected with the verb reor (to judge) in the same manner as pax (peace) and pactio (compact) are connected with the verb paciscor (to make a compact); and accordingly, as peace implies the compact, of which it is the result, and by which its conditions are duly determined, so also res implies the ratio, of which it is the concrete result, and by which it is confined between the bounds of a determinate quiddity. Whether the English words thing, thought, and to think bear to one another the same relation as the Latin res, ratio, and reor, we are not ready to decide.
7. The verb to be has not exactly the same meaning, when applied to a complete being, as when applied to its constituent principles. Of the complete being we say that it is simply and completely. Of the essential act we also say that it is, but not absolutely nor completely, because it has no existence apart from its term; existence being the result of the position of the one in the other. Of the essential term we should not say precisely that it is, but rather that it has being. This adjective predication is here employed, because the being of the term is wholly due to its act, without which the term would be nothing, as we have already shown; and therefore the term is not a being, but only has the being borrowed from its act, just as the geometric centre has no being but that which it receives from the circumference. Of the complement we do not say that it is, or that it exists, because the complement is the formal existence, not of itself, but of the being of which it is the complement, and therefore must be predicated of the existent being, not of itself. Thus we cannot correctly say that loquacity talks, nor that velocity runs: and for the same reason we should not say that existence exists; for as it is the woman that talks by her loquacity, and the horse that runs with its velocity, so it is the complete being that exists by its own existence.
Nevertheless, the verb to be, when used in a logical sense to express the existence of an agreement between a predicate and a subject, or any other mental relation between objects of thought, applies equally to all things conceived, whatever their degree of reality; because, inasmuch as such things are actually known, they are all equally actual in our intellectual faculty.