Commentaria in Primam Partem Summae Theologiae

A clear title. – In the body, four parts: first, the manner of investigating the divine eternity; second, he pursues it with respect to the parts placed in the intrinsic definition, there: For ¹; third, with respect to the parts placed in the definition as added, there: Likewise those things are said ²; fourth, applying everything to the matter at hand, the question is answered affirmatively, there: Therefore thus ³.

II. As to the first point: Eternity is to be known through time. – It is proved: because it is related to it as the simple to the composite. For eternity, as will be shown⁴, is unity, while time is number: the former without succession, the latter consisting of before and after, etc. Now it is evident that number is composite with respect to unity: and likewise before and after compose, with respect to that which stands without these differences.

III. As to the second: The intelligibility of eternity consists in the apprehension of the uniformity of that which is wholly outside motion. — It is explained. The intelligibility of time consists in the numbering of before and after in motion: therefore. The consequence is proved: because they are proportionally related, just as time is to the succession of part after part in motion, so is eternity to a thing lacking these.

IV. Note here that this proposition as set down in the text, namely the ratio of eternity consists in the apprehension of uniformity, can be expounded in two ways with respect to the phrase in apprehension. In one way, so that it signifies eternity's consisting in being apprehended or known: thus that eternity would be completive by the soul, just as is said of time. And thus, in my judgment, it is not to be understood: because the unity of everlasting uniformity exists in act without the act of the soul, no less than does the unity of the divine essence. In another way, so that it signifies the same as in objective conception, which by frequent usage we call a ratio; as if he had said: the ratio of eternity consists in apprehension, that is, in the ratio of uniformity. And this is the intended meaning.

Yet it can still be explained in two ways. For it may be interpreted formally or materially: formally, indeed, so that the ratio of eternity is uniformity itself; but materially, so that it is the unity of uniformity. And although some think this text must be interpreted materially, on account of the words of St. Thomas in I Sent., dist. XIX, qu. II, art. I (where he says that just as numbered before and after constitute time, so the permanence of the act as one by unity, insofar as it has the ratio of a measure, is eternity); and from this they think all the objections of Aureol, recited in the ninth distinction of the First Book ⁵ by Capreolus, are answered—objections which proceed against this saying as understood formally and not materially—nevertheless I understand this text formally, as well as the others, moved by this reason: nothing compels a material sense; for the formal understanding is always preferred to the others, provided it can be preserved equally.

Know, therefore, that since uniformity is a species of unity (for it speaks of unity contracted to a form: for we say synonymously of a uniform thing that it is a thing of one form), to add unity to uniformity is a redundancy; just as to add animal to man. Hence in I Sent.⁶ it is not said that "uniformity acts as one," but that "permanence acts as one." And accordingly, to say that eternity is uniformity and to say that it is unity do not differ, except that uniformity is said more specifically, more perfectly, and better; just as the proximate genus, rather than the remote, better explains the nature of a thing universally. And therefore deservedly in this gloss, published last, the better explanation has been given. The account of eternity, then, consists in the account of uniformity, insofar as uniformity has the character of a measure. –

It is clear, moreover, that this is the meaning of the text, from the fact that the apprehension (that is, the account) of uniformity is expressly set in opposition to the numbering of the prior and posterior of motion.

V. But Aureol's arguments are easily answered. For they consist in these two points. The first is this. Uniformity is immutability itself, and consequently it is that which is measured by eternity; therefore it is not formally eternity. The consequence holds: because immutability is one attribute, and eternity another. The antecedent is proved: because uniformity is opposed to motion with respect to its variety; therefore. – The second is this. Time is not formally the disformity of motion; therefore eternity is not formally the uniformity of what is outside motion. And the inference holds from the course of this passage of the text.

To these things it is answered, by showing how uniformity is related to immutability. For a thing, as was made clear in the preceding question⁷, is said to be and is immutable, through the negation of any potency whatever to be otherwise: and from this there arises in it the negation of all succession, and consequently of all number of prior and posterior. This, however, when the ratio of measure is added, is to be uniform. For uniformity posits nothing other than one (to which first of all the ratio of measure belongs, as is said in Book X of the Metaphysics⁸) in form, taking form in the most universal way. And therefore we use the name of uniformity also in motion, just as unity likewise extends to all things. And hence it comes about that uniformity is manifold, according to the things to which it is applied, just as unity is: for the uniformity of motion is one thing, that of a permanent thing another, that of what is measured another, that of the measure another. And yet one arguing uses the word "uniformity" as if it were univocal, contrary to the doctrine of Aristotle, Book IV of the Metaphysics⁹

Formally, therefore, against Aureol's arguments, it is denied that uniformity is formally immutability: rather, it is as its passion. And likewise it is denied that it is what is measured: rather, it is the measure. As to the proof, however, it is said that uniformity is opposed to the variety of motion not absolutely, but to motion in the way in which we first call motion uniform. But this is not what is being discussed here: rather, uniformity is being discussed insofar as it is the measure of immutability. – To the second, however, the inference is denied: since the disformity of motion and the uniformity of an immobile thing are not proportionally related to the ratio of time and eternity. For for the ratio of eternity, the unity of an immutable form suffices; but for the ratio of time, the diversity of the form of motion does not suffice, but there is required a diversity of such a form, namely of a prior one after a posterior one as such. And therefore, since the disformity of motion signifies nothing but a diverse form of motion, it does not posit number of such a form of motion according to priority and posteriority; and consequently it does not suffice for the ratio of time. The uniformity of an immobile thing, however, because it posits the unity of every form, that is, of the condition of the immutable thing, embraces all the constituents of eternity formally.

VI. As to the third point¹⁰: A wholly unchangeable being lacks a beginning and an end. – It is proved: because it lacks succession. This is explained: because what is measured by time has a beginning and an end in time, from the fact that everything moved has a beginning and an end.

VII. Note here briefly, since these points are taken from Book IV of the Physics, that the present discussion is directly concerned with the beginning and end of duration, except for the last proposition, in which it is proved that what is measured by time has the termini of its duration from the termini of the subject of the motion. For he is not speaking of the termini of the duration of the subject, since a mobile thing, say the heaven, could be posited as eternal; but rather of the termini of the magnitude of the subject. And his intention is that, because every mobile thing begins to be moved from some terminus within itself and is moved up to another terminus within itself, therefore everything measured by time has a beginning and an end of its duration. And this is an excellent reason a priori: namely, because prior and posterior in motion and time derive from the prior and posterior of the magnitude of the mobile thing and of the space, as is clear in Book IV ¹¹ and Book VI of the Physics¹² Now I have called "terminus from which" and "terminus to which" either those which are such both formally and materially, as in rectilinear motion; or formally only, as in circular motion. Nor does it stand in the way if the heaven is posited as having been moved from eternity: because, as is said in Book II of On the Heavens¹³ it suffices that it began virtually, that is, that it have within itself that from which, had it begun, its motion would have been initiated, say the point of Aries.

VIII. As to the fourth¹⁴, the elicited responsive conclusion is stated affirmatively, namely: That definition is fitting. –

It is proved: because eternity is made known from two things: namely, from its proper measure, in the words interminabilis vitae; and from its proper quiddity, in the words tota simul existens.

IX. Note here that, because the definition is investigated through a compositional process aided by division, the text accordingly distinguished, on the side of the measure, the measure of duration as measured by the mode of successive number and by the mode of an immobile unity: and having excluded the first, because it is time, it introduced the second. On the side of the thing measured, however, it distinguished the thing measured into that which is terminated at beginning and end, and into that which is unbounded on both sides: and having excluded the first, because it is temporal, it introduced the second. And since these points are posited in the definition of eternity brought forward, the conclusion reached is fitting. – Nor does it matter that the word perfect was omitted: first, because it was touched upon implicitly, by positing the uniformity of what is altogether immobile; for such is not the uniformity of the now of time, since it is not outside motion. Second, because this was to be explained in the reply to the fifth objection.