Commentaria in Primam Partem Summae Theologiae

In the title, note the two terms, namely subject and predicate: sacra doctrina sacred doctrine is here taken for the whole of theological science; and una one stands for a specific unity, indeed that of the most special species. And note carefully that what is asked here is not whether it is one simple quality, but whether it is one science according to species; whatever may be said of the mode of unity of this science in general—whether it is one by a unity of simplicity, or by a unity of order, etc.—is not to the point. For nothing depends on the matter at hand as to what anyone may think about this. It suffices here to inquire whether theology is one science according to the most special species; or whether it is not, but is divisible into many species; and, just as mathematics is divided into geometry, arithmetic, etc., so this might be divided into several sciences, say concerning God, concerning Christ, concerning morals.

II. In the body there is one conclusion, answering the question affirmatively: Sacred doctrine is one science. – It is proved. The unity of a power and of a habit is according to the unity of the formal aspect of its object: therefore sacred doctrine is one science.

The antecedent is declared in the power of sight and the formal reason of its object. – The consequence, however, is proved. All things considered in sacred doctrine share in one formal reason of the object of this science, namely, the light of divine revelation: therefore.

III. To make this argument evident, note that there is a twofold formal ratio of the object in science: one of the object as a thing, the other of the object as an object; or one as what, the other as under which. The formal ratio of the object as a thing, or what, is the ratio of the thing known which first terminates the act of that habit, from which the passions of that subject flow, and which is the medium in the first demonstration; as entity in metaphysics, quantity in mathematics, and mobility in natural philosophy. The formal ratio of the object as object, or under which, however, is such immateriality, or such a mode of abstracting and defining: for instance, without all matter in metaphysics, with matter intelligible only in mathematics, and with sensible matter, though not this matter, in natural philosophy.

IV. The necessity, quality, and distinction of these formal reasons must be drawn from the distinction of the two genera in which the object of a science must be located. For it is necessary that it be formally such a thing, in such a way knowable. And therefore it must have the formal reason constituting it formally in such a real being, and the formal reason constituting it formally in such an being of the knowable; and so it is placed both in the genus of things and in the genus of knowables, just as the object of sense is in two genera, namely under passible quality and under the sensible. For the differences and species of passible quality are one thing, and those of the sensible another. Of the former, the species are color, sound, odor, etc.; of the latter, the species are visible, audible, odorous. The differences of the former are constitutive of the objects themselves; the differences of the latter add nothing to those objects. The former again constitute subjects, the latter passions, according to II De Anima¹, where visible is posited as a predicate of the second mode of per se, that is, a passion, of color. And just as the distinction and multiplication of sense is not attended to according to any division whatever of sensible quality, but only according to that division into those five from which flows the division of the per se sensible as sensible (namely by the proper differences of the sensible itself, for instance, as altering sense in such a way, etc.), since sense is said to be divided according to the division of the sensible insofar as it is sensible: so the object of science is in the genus of being and in the genus of the speculable, such that these two genera are divided by other and other proper differences into their proper species. For the proper differences of being are constitutive of beings in their real genera, just as being through itself constitutes substance, and being in another constitutes accident, etc.; but the proper differences of the speculable add nothing to beings. Hence the former intrinsically constitute subjects, while the latter constitute their quasi-passions, since indeed the speculability of a being is a passion. And therefore only that division of being diversifies speculative habits which entails the proper division of the speculable as speculable, by the proper differences of the speculable itself: which are taken according to the diversity of the mode of abstracting from matter VI Metaphys.² So that first the reason of being is divided into entity simply, quantity, mobility, and deity. And from this flows another division of the knowable: into the knowable by metaphysical light, that is, a medium illumined by abstraction from all matter; and by mathematical light, that is, a medium illumined by immateriality from sensible matter, yet shadowed by intelligible matter; and by physical light shadowed, that is, a medium shadowed by sensible matter but illumined by the separation of individual conditions; and by divine light, that is, a medium shining with divine light, which constitutes theological knowable.

V. Therefore the object of a science has a twofold formal ratio: one quidditative in respect of itself as it is a thing; the other denominative of itself simply, but quidditative in respect of itself as it stands under the genus of the knowable—which is to be under the genus of object, since the knowable is a species of object. And therefore it was said that one of these belongs to the object as the object is an object. And since, just as sense is distinguished according to the distinction of the sensible as such, so science is divided according to the division of the knowable as such, it follows that where there is one most special species of the knowable, there there must be only one species of science, as also happens in sense and the sensible; and where several differences of the knowable as such are found, diverse species of science must be posited. And if you add to this that the differences of the knowable as such are themselves the formal ratios of the knowable object as it is an object, it follows of necessity that the specific unity and diversity of sciences is attended to according to the unity and diversity of the formal ratios of objects as they are objects; or, which is the same, of the formal ratios under which things are known. — And this is what is said in the text, when the reason why theology is one science is assigned from the unity of the formal ratio under which, or of the object as object, namely the light of divine revelation: for all things are said to be considered in theology insofar as they are divinely revelable. And thus the force and meaning of the argument brought forward in the text is clear.

VI. Concerning this argument as thus expounded, a threefold doubt arises: the first concerning the argument itself; the second concerning the antecedent³; the third concerning the proposition assumed in the proof of the consequence⁴. And each is to be resolved in turn, in the order proposed.

Concerning the reason of the letter, then,⁵ a doubt arises, because it has fallen into equivocation. For in the antecedent it speaks of the formal reason of the object as it is a thing (as is clear from its proof in the case of sight: for the reason of color is assumed to be the formal reason of the visible; but the reason of color is the formal reason of the visible insofar as it is a thing, as is evident): but the proof of the consequence speaks of the formal reason of the object as it is an object; for it assumes revelability to be the formal reason of the object of theology. Therefore an equivocation is manifestly committed, by assuming the formal reason of the object as object under the formal reason of the object as thing.

VII. To this it is said, by denying the assumption. For the antecedent supposes indistinctly for the formal ratio of the object, whether as a thing or as an object: although it has been made manifest with respect to the formal ratio of the object as a thing; then because that is better known; and then because those two formal ratios convertibly follow upon one another, as subject and passion, as was said⁶. And therefore without equivocation the inference could be drawn concerning the formal ratio of the object as object, namely, revelability.

And rightly the formal aspect of the object as object was subsumed, rather than the formal aspect of the object as thing. First, because the formal aspect of the theological object as thing had not yet been assigned, but was to be discussed in article 7; whereas another was assigned in articles 1 and 2. Second, because that formal aspect as thing does not imply a most special species of the object as such, and consequently neither a most special species of science, as will now be shown at ⁷; and thus it would not have achieved its intended purpose.

VIII. But against this reply a greater difficulty arises. For if it is true that the formal ratio of the object as thing, and its formal ratio as object, are related to each other as subject and passion convertibly, as the aforementioned reply maintains, and as was said above⁸; it follows that the theology of the blessed and ours agree in one formal ratio of the object as object, and consequently are one science according to the most special species. And consequently the whole subalternation argued in the preceding article collapses, as Scotus argued there⁹: because the same thing is not subalternated to itself. — The consequence is proved thus. These theologies agree in the formal ratio of the object as thing, because deity is the formal ratio in both cases: therefore also in the formal ratio of the object as object. The consequence is evident. For those two formal ratios infer each other convertibly, as subject and passion, according to what has been said: for agreement in the unity of the subject requires that they agree in the unity of that subject's passion, since the passion is inseparable from the subject.

IX. To this it is said that that proposition, namely: the formal ratio of the object as a thing, and its ratio as an object, are convertible, etc., is most true, rightly understood, namely concerning the formal ratio of the object as such adequately proportioned to the formal ratio of the thing. But otherwise it stands with the formal ratio of the object as object inadequately proportioned to the formal ratio of the object as thing (if it happens that some object has an inadequate ratio): for the inadequate ratio need not be converted with the ratio of the thing; rather it indeed entails that one, but is not necessarily entailed by it. So it is in the case at hand. For to the deity there corresponds only one formal ratio adequate to the object as object, and this is the divine light: but that formal ratio is not one in species, but in genus; and it is divided into the evident divine light, and the revealing divine light (abstracting from evidence and inevidence), and the inevident divine light. And the first is the ratio under which the theology of the blessed proceeds, the second ours, the third faith. And therefore, with the unity of the formal ratio of the object as thing, there stands a specific diversity of the formal ratios of that object as object; and consequently a specific diversity of habits. And therefore, although the deity is converted with that adequate ratio, and they mutually entail each other, nevertheless it is not converted with any species of it. And consequently it does not determinately entail any of them, but is entailed by each. For this holds: God under the ratio of deity is the object of such a science, therefore under the divine light, and conversely: but it does not hold, therefore under the evident light; or, therefore under the light of revelation, etc.

X. And so that you may know the root of this reply, note that, although the two formal rationes so often named are related convertibly as subject and passion, they are nevertheless not related convertibly in degree of unity; so that, if one of them is one with a most specific specific unity, the other is not therefore one in that way; and if one is one in genus, the other is not therefore one generically. Indeed, the complete opposite appears in several cases. For in the object of metaphysics, the ratio of being is one degree less than a genus: and yet the ratio of its speculability, namely abstraction from sensible and intelligible matter, is one according to the most specific species. And the same appears in geometry and arithmetic, whose subjects have generic unity as things, and atomic specific unity as objects. And conversely, sometimes the ratio of a thing is one according to an atomic species, and the ratio of the object as such is one according to genus; as in the case at hand with the deity and the divine light. And in the opposite manner, and deservedly so, the object of theology is related to the objects of the aforementioned sciences: because the formal object as a thing is infinite. For it accords with reason that, as a thing, an infinite species exceeds the finite species of the object, even though it is equal to its genus.

XI. It could also be said that the formal ratio of the object is assigned in two ways: namely, on the side of the object, and this is convertible with the ratio of the thing; or on the side of a defective power, and this is not convertible, but infers the formal ratio of the thing, and is not inferred from it. So it is in the case at hand. For deity and the divine light are convertible: but deity and this divine light so understood are not convertible; rather, such a light infers and encloses within itself the deity, but not conversely. And therefore it would have been licit even to subsume the light of revelation under the formal ratio of the thing, since that is enclosed within it.

XII. Concerning the antecedent¹⁰ there is a doubt, having a very wide field, about the unity and diversity of habit and power on account of the object: and therefore one ought rather to make a special question of this. Let it suffice here that that antecedent is found in II On the Soul¹¹, where it is said that powers are distinguished by their acts, and acts by their objects: for the same judgment holds of act and habit in this respect.

XIII. Concerning the proposition assumed in the proof of the consequence¹², namely: all things considered in sacred doctrine agree in one formal ratio, that is, divine revelability, a twofold doubt arises: first, against the proposition in itself; second, against it as applied to inferring the specific unity of theology.

Against this very position in itself, Albert the Great argues in Book I of his Summa Theologiae¹³: Revealedness adds nothing to the thing revealed; therefore it is not a formal ratio. He holds that the consequence follows, because a formal ratio adds something to the object whose ratio it is. — Next, Aureol argues ¹⁴: The divine light is related to theology as the agent intellect is related to the acquired sciences; therefore it is not a formal ratio. — Moreover, God is related as teacher; therefore his revelation is not a formal ratio.

Against this same argument, by which he infers the unity of science, Aureol argues¹⁵. If God were to reveal philosophy and geometry at once, they would not for that reason be one science; therefore from the unity of revelation there does not follow the unity of science, etc.

XIV. For the clarification of the answers to these objections, beyond what has been said, know that the light of divine revelation can be related to some science in two ways. First, as that which infuses to that which is infused, or as an efficient cause to its effect. And in this way it does not give unity to a science, since it could infuse all sciences, however diverse they may be. In another way, it is related to a science as the reason or mode of knowing the object, under which, or by means of which, the revealed thing is attained by the knower. And in this way it gives unity to a science. And although this twofold relation concurs here simultaneously, it is not necessary for them always to concur together. For if God were to reveal geometry to me, revelation would not for that reason be the formal reason under which I know the object of geometry, since I would know geometrical things under that very same formal reason under which other geometers know them. But in theology both relations concur: because this science is had only through infusion; and all the things known in it are attained, and assent is given to them, as they stand under the divine light as their mode of intelligibility. And therefore the unity of theology is inferred in the text from the unity of the divine light—not as it is that which infuses, but as it is the formal reason under which, in the manner explained above.

XV. And from these the answer to the objections is easily clear¹⁶. For Albert's argument equivocates on the notion of object, taking the formal notion of the object as a thing, while excluding the formal notion of the object as object, etc. - But the first argument of Aureol fails: because the divine light functions as the agent intellect, but not only so; it also functions as the formal notion of the object insofar as it is an object. - The second likewise fails in the same way: because the teacher's illumination here is not only an infusion, but also the formal notion of the thing infused, under which it is infused. And again, it is false that from one teacher as such many sciences could proceed.

Finally, as for Aureol, it is already clear that the inference is worthless: because the divine light, by infusing physics and mathematics at the same time, does not concur as the ratio of the object qua object, but only as infusing, etc.