Commentaria in Summam contra Gentiles, Liber III

After St. Thomas showed which works are miracles, he intends further to make clear to whom it belongs to work miracles¹.

Concerning this, however, he does two things: first, he shows that God alone can work miracles; second, that other spiritual substances perform certain wonderful works which are not true miracles, in the following chapter.

I. Because, moreover, this proposition, God alone can work miracles, has two exponents—namely, God can work miracles, and, No one other than God can do this—St. Thomas proves both in this chapter: first, the second; second, the first².

He argues therefore, first, thus: Every creature is constituted under the order that God established in things. Therefore, no creature can work above this order, which is to work miracles. — The consequence is proved: Because that which is totally constituted under an order cannot work outside that order.

For the understanding of this argument, it must be considered, from the teaching of St. Thomas in the First Part, q. cx, a. 4, that for the notion of a miracle it is not sufficient that something be outside the order and inclination of some particular created power, but it is required that it be outside the order of the whole of created power: that is, that no created power can effect that result with all its conditions. It is evident, however, that a particular created power cannot work outside the order of the whole of created nature, since it works according to its own order and inclination, which order is contained under the universal order imposed on the universe of creatures by God, just as a part is contained in its whole. And therefore no created power can work miracles. And it is along these lines that this argument proceeds.

Hence also that proposition which St. Thomas assumes—namely, That which is totally constituted under an order cannot work outside that order—is understood in this sense: that if something, according to all its power, is contained under some total order as a part of that order, it cannot work outside that total order. For the opposite implies a contradiction. For if something by its own power works outside some total order, it follows that according to its power it is outside that whole order, since it works that to which no power contained in that order can extend itself. And thus, if it is posited that something contained in some whole order works outside that whole order, it is posited that the same thing, according to its power, is in some order and is not in that order.

II. Secondly: The power of every creature is limited to some determinate effect, or to some effects. Therefore, whatever is done by the power of any creature cannot properly be called a miracle; but that can well be which is done by divine power, which is infinite, and on that account incomprehensible. — The consequence is proved: Because when some finite power works its proper effect to which it is determined, it is not a miracle.

For the understanding of this, it must be considered, from the teaching of St. Thomas in the place cited above, ad 2; and q. cxiv, a. 4; likewise II Sent., d. xviii, q. 1, a. 3; and IV Sent., d. xvii, q. 1, a 5³, that something can be called a miracle in two ways: in one way, with respect to us only; in another way, simpliciter. With respect to us, it is called a miracle when something happens outside the order of created nature known to us, by a created power unknown to us, although in itself it is knowable and comprehensible by a created intellect. But simpliciter, that is called a miracle which occurs outside the order of the whole of created nature, by a power incomprehensible in itself by any created intellect. Therefore, because every finite power—such as every created power is—is comprehensible by some created intellect, and consequently is not a cause that is hidden simpliciter; whereas infinite power is incomprehensible, and consequently entirely hidden: therefore St. Thomas very well says that those things which are done by a finite power are not miracles simpliciter, but can be wonderful to one who is ignorant of such a power, and consequently miracles with respect to him (just as to one ignorant of the power of a magnet it is wonderful that iron is attracted by it, and to one ignorant of the power of a certain fish it seems wonderful that it holds back a ship); while those things which are done by an infinite power, such as the divine power is, are truly and simpliciter miracles—understand, if the other conditions set forth in the preceding chapter are also present.

III. Thirdly: No creature can act upon any thing except that which is in the potency of that thing. Therefore, there are many miracles that can be done by no created power. — The antecedent is proved: Because, since to create belongs to God alone, every creature in its action requires a subject. Nothing of such a kind, however, can act except toward those things to which the subject is in potency, since it works only to educe the subject from potency to act. — The consequence, however, is proved: Because many miracles are performed divinely when there is done in some thing by divine power that which is not in the potency of that thing: as that a dead man should return to life, that the sun should go backward, that two bodies should be together.

Note that in this argument, by the potency of the subject is understood natural potency simpliciter, in the way in which a subject is said to be in potency to a form educible from its potency by a natural agent. But obediential potency is not understood, according to which something is said to be in potency to whatever God has willed to effect in it: because in that way all miracles, worked in whatever thing, are in the potency of that thing.

Note also that this argument does not prove universally that no miracles can be performed by created power, but only some. For God also sometimes works miraculously in a thing that to which it is in natural potency, although he effects it in another way: as when he restores someone from a fever immediately to health. And therefore, from the fact that a created power does not act upon a thing except toward that to which it is in natural potency, it cannot be concluded universally that no miracles can be performed through created power.

IV. Fourthly: and it is a confirmation of the preceding argument. The effects according to which a subject is reduced from potency to act either are naturally suited to be brought about through superior causes alone, or they are not. But in neither of those ways is it a miracle. Therefore, in no way can any miracles be worked by the power of superior causes.

The major premise is proved: Because, since the subject upon which an agent acts has an order both to the agent through which it is reduced to act and to the act to which it is reduced, just as it is in potency to a determinate act, so it is to a determinate agent. This is shown from the fact that an agent is required in diverse ways for reduction to a diverse act; and this is made clear by examples.

The minor, however, is proved as to the first part by example: For it is not a miracle when animals are generated from putrefaction without seed. — As to the second part, however: because for the completion of effects that are not naturally suited to be brought about by superior causes alone, inferior particular causes are required. But when an effect is produced by a superior cause through the mediation of proper principles, it is not a miracle.

2. Concerning the proof of the major, it must be noted that St. Thomas takes the order of the subject to the form and to the agent from the definition of passive potency given in V Metaph.⁴. For it is defined as the principle of being changed by another insofar as it is another. From this, however, it is held that the subject from whose potency some act is educed expresses an order not only to the act into which it can be educed through transmutation, but also to the agent by which it has to be transmuted and reduced to act. From this, moreover, it further follows that, since the naturalness of a potency is a mode of that potency; and a passive potency in its notion expresses an order to the act and to the agent: that alone will be called a natural potency which looks to an act that is not above the order of natural acts, and has for its proper active principle some agent that is contained in the order of natural agents. For just as passive potency taken in common has to be defined through the act and through the agent, so natural passive potency has to be defined through the natural act and through the natural agent: just as a violent potency is called that which is receptive of a violent act (that is, one contrary to itself) from an agent acting upon it through violence.

From this is evident the error of Scotus in I Sent., q. 1 of the Prologue⁵, who holds that our end, which is the vision of the divine essence, is natural to our soul, but supernaturally acquirable. For it is evident that this is false. Because by no created power can the soul be educed into the act of that end. And consequently the soul does not have a natural potency simpliciter toward it, but only an obediential one: although there is something of naturalness in it, as was said in the preceding sections⁶, insofar as its nature is constituted capable of that beatitude, and is ordered to it from its first institution by God.

The opinion of Scotus can, however, be sustained if by such natural potency is understood the bare capacity of the potency and the non-repugnance to such an act: as he seems to intend in the Quodlibets, question xiv⁷.

3. It must also be noted that this argument proceeds from the same foundation from which the preceding one proceeded—namely, from this, that no creature can effect in anything except that which is in the potency of the subject. For if to this foundation is joined what was said above⁸—namely, that a miracle is outside the order of the whole of creaturely nature—the argument proceeds very well. For if by a creature only that can be done which is educed from the potency of the subject; and that which is educed from the potency of the subject is naturally suited to be educed into act either by universal causes alone, or by them through the mediation of proper causes: it is necessary that everything that is done by a creature be done in one of those ways. But that which is done in that manner and in that order in which it is naturally suited to be done is not a miracle, since it is according to the order of nature, not outside the order of nature. Nothing, therefore, that is done by superior creatures is a miracle.

V. Fifthly, it is argued from the same foundation: Every creature of necessity must use a subject⁹ in order to do anything. Nor can it do anything except that to which the subject is in potency. Therefore, it cannot do anything unless it reduces the subject into act through determinate means. Therefore, etc.

The first consequence is proved: Because it seems to be of the same reason that something works from a subject, and that it works that to which the subject is in potency, and in an orderly way through determinate means, because the subject does not become in proximate potency to the ultimate until it has been in act in the intermediate¹⁰. This is made clear in food being transmuted into flesh. — The second, however, is proved: Because miracles arise from the fact that some effect is produced not in that order in which it can naturally come to be.

2. Concerning the proof of the first consequence, it must be considered that a subject which is in potency to several acts regards them not confusedly, but with a certain order, as was shown in the second book¹¹. For it must first be actuated through the prior act by way of generation, and afterward through the posterior act: because the prior act is potential with respect to the posterior act, and through it the subject is disposed for the reception of the posterior act, as is evident in the generation of flesh from food, which must first be converted into blood before into flesh; and in the generation of man from menstrual blood, in which the matter must first be transmuted to the vegetative and sensitive before to the intellective. Because, therefore, a power that necessarily requires a subject in its action does not do anything except that to which the subject is in potency, and in the manner in which it is in potency, it is necessary that it reduce the subject itself to act according to the order of acts to which it is in potency. And therefore it cannot reduce it to the ultimate act unless it first reduces it to the prior acts. This is to work in an orderly way through determinate means. And this is the foundation of that consequence.

VI. Sixthly: Local motion is the cause of all other motions. Therefore, the effect that is brought about in these lower things by an incorporeal agent, which properly cannot be moved locally, must occur through something moved locally. Therefore, created incorporeal substances cannot work miracles by their own power. Therefore, much less can corporeal substances. Therefore, etc.

The antecedent is proved: Because local motion is the first of motions. The first in any genus is the cause of those that follow. — The first consequence is proved: Because effects that are produced in lower things—namely, by a created agent—must of necessity be produced through some generation or alteration. — The second is proved: Because effects that are brought about by incorporeal substances through corporeal instruments are not miraculous, since bodies do not work except naturally¹². — The third, however: because every action of a corporeal substance is natural—namely, clearly and manifestly, speaking of its proper action.

Note, when St. Thomas says that an incorporeal agent cannot properly be moved locally, that he added properly for this reason: because, just as incorporeal substances are improperly in a place—for they are in a place because they work in a place, but not because they are circumscribed by a place—so also they can improperly be said to be moved locally: because, namely, by their power they successively touch diverse places, but not because they successively occupy diverse places through containment by a place.

VII. Although mention of the motion of an angel has occurred incidentally, yet because this matter in the teaching of St. Thomas is extremely difficult, it will not be beside the point if I explain a few things. For three things are said in the First Part, question LIII, which seem to present difficulty.

The first is that, besides the discontinuous local motion of an angel, there can also be some continuous motion of it: because, namely, it can successively leave a divisible place in which it previously worked, successively and part by part occupying another place¹³.

The second is, that such motion takes place in a continuous time which is distinguished from the time measuring the motion of the heaven¹⁴.

The third is, that no motion of an angel, neither continuous, I say, nor discrete, can be in an instant¹⁵.

2. For concerning the first statement, a doubt arises. For St. Thomas himself, in the first article of that question, describing the local motion of an angel, says that it is necessary that the local motion of an angel be nothing other than diverse contacts of diverse places successively, and not simultaneously. For from this it is argued thus: The local motion of an angel is nothing other than diverse contacts of diverse places successively. But diverse angelic contacts succeeding one another take place according to diverse operations. Therefore, the local motion of an angel requires its diverse operations concerning a place. But the diverse operations of an angel are not continuous, since each one is measured by its own instant. Therefore, the motion of an angel cannot be continuous.

It is confirmed: Because St. Thomas himself, on this account of motion, in I Sent., d. XXXVII, q. IV, a. 1, holds that the motion of an angel is not continuous.

3. Concerning the second; a doubt arises first¹⁶, because in Quodlibet III, a. 5¹⁷, it is shown that, because all continuous motions agree in one genus insofar as they are measurable, therefore they can have one common measure. And on that account of all continuous motions there can be one common time. If therefore it is posited that some motion of an angel is continuous, it is not unfitting that it be measured by the same continuous time as other motions.

Secondly: When the motion of an angel is said to be continuous, either by the name 'motion' are understood the immanent operations themselves in the angel, by which the exterior effect is commanded and produced; or the effects produced in a place through such operations; or other transient operations. Not the first: Because any immanent operation in an angel is produced all at once, and is measured by an instant of discrete time as in an adequate measure; and thus several operations of this kind cannot be measured by continuous time. — If the second: in this way it is not unfitting for angelic operations to be measured by the time measuring celestial motion. For it is not unfitting for the effect of an angelic operation to be measured by such time, just as neither is a divine effect. — If the third: since a transient action is the same as its term, the action by which an angel moves the heaven will be the same as the motion of the heaven itself; and thus, since the motion of the heaven is measured by time, the action of the angel itself will also be measured by common time; and thus the motion of the angel will be in common time.

4. Concerning the third, there is also doubt¹⁸. For that change through which the terminus a quo is cast off all at once, and the terminus ad quem is acquired all at once, is an instantaneous change. For this is evident in substantial generation, and in illumination, which are called instantaneous changes.

It is also evident by reason¹⁹: For that which is moved in time must be partly in the terminus a quo and partly in the terminus ad quem, as is held in VI Physics²⁰. This, however, is not found where one whole terminus is cast off all at once, and the other is acquired all at once. Therefore, etc. — But in the discrete motion of an angel, one whole place is abandoned all at once, and another whole place is occupied all at once. Therefore, the discrete motion of an angel is in an instant: although its continuous motion is in time, just as is the motion of bodies.

VIII. For the understanding of the first doubt, it must be considered first that, since an angel is not defined to a place through an operation according as it proceeds from its essence, but according as it is terminated at what is worked in the place, as St. Thomas says in I Sent., d. XXXVII, q. IV, a. 2; in order to see how an angel is moved from place to place continuously or discretely, one must look to the operations themselves according as it works toward what is worked around diverse places. And because in the First Part, q. LIII, he speaks of the continuous motion of an angel proportionately to the local motion of a body, one must come to the knowledge of angelic motion from the motion of a body.

2. It must be considered secondly that, since the local motion of a body, according as it is successive, is divided according to the division of magnitude, and has continuity according to the continuation of magnitude; just as magnitude is indeed one by continuity, but nevertheless has several parts of which one is not another; so the motion of a body over a magnitude is indeed one by continuity, but nevertheless has several parts, each of which is a motion, corresponding to the diverse parts of the magnitude. Hence it can be said that in the transit of a body over one magnitude there is one total motion, but several partial motions, out of which the total motion itself is integrated: just as also the total magnitude is constituted out of several parts, each of which is a magnitude. Thus therefore, speaking proportionately of the local motion of an angel, when an angel is moved by continuous motion by successively abandoning a prior place, and successively occupying a posterior place according to the order of the parts, there must be there one contact and one total operation according to continuity, just as the places themselves in which it is continuously moved have continuity: but nevertheless that contact and that operation have several parts, according as it is applied to several parts of the magnitude through something worked in them. And therefore it can be said that in such continuous motion there is indeed a single total contact, but many partial contacts.

Whether, however, according as the operation goes forth from the essence, there are many partial contacts in such continuous motion? — It seems must be said that, if an angel acts upon bodies by command and an act of the will alone, in such a way that the execution is not really distinguished from the command, it is not possible for there to be any plurality in that contact. For there cannot be there one willing having continuity integrated from several parts succeeding one another, since every immanent operation of an angel is whole all at once and indivisible. Nor can there be several commands corresponding to the several places that are traversed by the angel in continuous motion: because, since the places traversed by the angel in such motion are infinite, just as in the motion of a body, it would be necessary to say that at the end of the motion the angel had elicited infinite acts of willing. Which is manifestly impossible: for the infinite cannot be traversed ²¹. — If, however, an angel acts upon bodies through some operation that is truly and formally transient, it must be said that in the same way in such a contact as it goes forth from the essence, there is a total unity and a partial plurality, just as there is also in it as it terminates at what is wrought in place. For, since such a contact and operation is the same as what is wrought, just as in bodily actions motion and action are the same as the term of motion; as what is wrought itself has succession and divisibility, so also the action itself proceeds successively and partibly from the operating angel himself.

3. From these things the answer to the doubt is easily evident. For it is said that even in the continuous motion of an angel there are in some way several contacts, according as they terminate at what is wrought: for there is there one total contact, but there are several partial contacts. And this suffices for the intention of St. Thomas.

When, however, it is urged that diverse operations of an angel are not continued: — it is said that this is true of immanent operations as they go forth from the essence of the angel. It is also true of total transient operations. But it is false of partial operations. For, as has been said, one operation of an angel, as it terminates at what is wrought, can have succession and partibility; and thus be integrated from several parts, any one of which can be called a partial operation, according as through it a part of the traversed magnitude is reached.

4. To the confirmation the answer is that, if we wish to maintain the statements of St. Thomas in I Sent. as not retracted by the statements in the First Part, we can reconcile both statements in two ways. First, that in I Sent. he is speaking of the motion of an angel by which he reaches several places through several total and completely distinct operations; but in the First Part he is speaking universally of the motion by which he reaches several places through several operations in whatever manner, whether, I say, they are total and completely distinct, or partial.

Second, that in I Sent. he is speaking of the nature of angelic motion so far as it is on the part of the angel: for, since he is outside magnitude, continuity does not belong to him in his motion on the part of his own substance. In the First Part, however, he is speaking of the nature of angelic motion both on the part of the angel and on the part of the magnitude in which he operates, and over which he is said to be moved locally. And therefore he posited that a certain motion of his can be discrete, while a certain one can be continuous: from the fact that he can both leave one place whole all at once; and he can successively abandon by parts the place in which he previously was, and successively occupy another in the same way.

IX. As to the second doubt ²², it must be noted first, from the doctrine of Aristotle in X Metaphysics, text 4 and following ²³, that the proper measure of anything ought to be connatural, or of the same nature with what is measured, not only according to agreement in a common and generic nature, but also according to agreement in a special nature, as regards that according to which something is measurable: for a line must be measured by a line, a surface by a surface, a weight by a weight, and so of others. And therefore, just as things agree or are distinguished in nature insofar as they are measurable, so they can or cannot be measured by one measure. For things that agree in one particular or specific ratio insofar as they are measurable can be measured by one specific measure; but things that share in one generic ratio but not in one specific ratio can be measured by one generic measure, but not by one according to species; while things that agree only in one analogous ratio can be measured by one analogous measure, but not by one generic and univocal measure. — But we are speaking of a per se and proper measure, not of a measure per accidens, or an exceeding measure.

2. It must be considered secondly that, since motion is of another ratio than time even in the ratio of quantity, it does not belong to measurable motion according to its whole self to be measured primarily by time, but it must be measured by another motion, namely the first and most simple in the genus of motions. But by means of that first motion itself, it can be measured by time: from the fact that time is the number of the first motion. And therefore, if there are some motions that have an order and dependence upon the first motion as upon their exemplar, and as upon the most perfect and most simple of their genus, they can be measured by the time numbering the first motion. If, however, there are some motions that do not have such an order to the first motion, they are not to be measured by the time measuring that motion.

3. Because, therefore, the local motion of an angel is not of the same ratio with the motion of any body, but an angel and a body are equivocally said to be moved locally: therefore the local motion of an angel does not depend on the motion of the heaven nor is it measured by it, and consequently neither is it to be measured by the time that is the number of the motion of the heaven. And this is the reason on account of which St. Thomas holds that the time measuring angelic motion is not the same as the time measuring the motion of the heaven and other bodily motions.

It must be noted, however, that an angel can be said to be moved locally in two ways: in one way, per se; in another way, per accidens. He is said to be moved by a continuous motion per se when by his operation he immediately touches diverse places successively, leaving one part after part, and occupying another in the same way. But per accidens, when he moves one body with a continuous motion, through the motion of which he successively has presence at diverse places, from the fact that the body moved by him successively occupies diverse places: as when he moves a body assumed by him, or a single stone, from place to place. What was said, therefore, that the motion of an angel is not measured by common time, is to be understood of his motion per se, but not of his motion per accidens. For in motion per accidens he is always in the same place per se, although he is moved per accidens: just as he who sits in a ship and is moved at the motion of the ship is in the same place per se, but is moved per accidens at the motion of the ship.

X. But concerning what has been said a doubt occurs. For, although the ratio of the local motion of an angel is one thing, and the ratio of the local motion of bodies is another, nevertheless both motions agree in the same ratio of continuity: for each has continuity from the continuity of magnitude. Since, therefore, motion is to be measured by the time measuring the motion of the heaven by reason of its continuity, it seems that each is measured by the same time, notwithstanding that they are called local motions equivocally. And thus the argument of St. Thomas does not seem to conclude.

2. The answer is: and it is said first that, although these motions have continuity from some one and the same thing, namely from magnitude, there is nevertheless not the same ratio of continuity in them. For the continuity of the local motion of bodies is the continuity either of the places successively circumscribing the moved body itself, or of the diverse ubis that are successively received in the moved body; and further its continuity not only arises from the continuity of the magnitude over which the motion takes place, but also from the continuity of the body that is moved. But the continuity of the motion of an angel is the continuity of diverse partial contacts by which the angel touches diverse places; and its continuity arises from the continuity of the magnitude over which the motion takes place alone, but not from any continuity of that which is moved.

It is said secondly, that from the common ratio of continuity things do not have it that they are measured by one specific measure, otherwise length, and surface, and motion, and weights ought to be measured by one measure: but from the particular ratio of continuity. And therefore, although there is one certain common ratio of continuity in all motions, both angelic and bodily, yet because there is one particular ratio of continuity in some and another in others, therefore they are measured by different proper measures: although those proper measures agree in the common ratio of continuous time.

3. Whether, however, the continuous motion of an angel is in the genus of quantity? — It seems must be said that, if the operation of an angel is itself nothing other than his command, as St. Thomas seems to wish in Quolibet. VI, a. 2 ²⁴; and De Malo, q. xvi, a. 1, ad 14; and De Spiritualibus Creaturis, a. 6, ad 8, the motion of an angel itself, so far as it is on the part of the operation, is not of the genus of quantity, since it is an immanent action: but on the part of the produced effect, it is not unfitting for it to be in the predicament of quantity per accidens, just as other motions are. — If, however, the operation itself is a truly transient operation, which is really the same as the term of the operation, thus it does not seem unfitting that it too should be in the genus of quantity per accidens: namely, as having continuity from magnitude, and likewise the time that measures such a continuous operation.

Although it could perhaps also be said that, while the operation itself, as a certain accident of a quantified thing, is quantified per accidens by a quantity of the genus of quantity; yet as the operation and continuous motion of an angel, it is not in the genus of quantity, but is continuous with a transcendent continuity. For just as the succession of immanent operations in an angel, which constitute his discrete motion, is not placed in the genus of quantity; nor is the time of motion measuring this kind of motion in the genus of quantity, but is a transcendent number: so the continuous motion of an angel is not in the genus of quantity, but is transcendent, and the time measuring it is a transcendent time. For quantity, which is a predicament, is found only in material things. — But let these things be stated with probability.

XI. To the arguments adduced above ²⁵, however, the answer is given. To the first, indeed, it is said first, that perhaps St. Thomas there held that no motion of an angel is continuous; and on account of this he said that all continuous motions are measured by one time. But in the First Part he held that a certain motion of an angel is continuous. Therefore, following his determination in the First Part, what he said elsewhere is not to be held. For the things he says in the Summa are to be held.

It is said secondly, maintaining the statements in the aforementioned Quodlibet, that he is speaking there of continuous motions that are univocally called motions: but not of those that are called motions equivocally, of which sort are the motion of an angel and the motion of bodies.

It is said thirdly that, just as these motions are in some way proportionally called motions analogically, so they are measured by one time by a unity of analogy and proportion. For all are measured by continuous time: although the ratio of this time is one, and the ratio of that time is another.

2. To the second it is said first, that by the name of angelic motion we understand not the immanent operation itself insofar as it is immanent: but either the effect at which the immanent operation itself terminates, insofar as it terminates the said action; or some action of the angel that is truly transient and has continuity.

When it is urged against the first, because it is not unfitting for such an effect to be measured by common time: — it is said that, although it is not unfitting for some effect of an angelic operation to be measured by common time, it is nevertheless unfitting for the effect of which we are speaking, as it successively terminates the operation of an angel, and as it is the motion by which the angel is said to be moved per se, to be measured by such time: since, as such, it is of another ratio from the motion of the heaven.

When, however, it is urged against the second, because, since the transient action itself is the same as the term of the action, the action by which an angel moves the heaven by continuous motion will be measured by common time, just as the motion of the heaven itself is: — it is said that the argument assumes what is false, namely that, while an angel moves the heaven, he is himself said to be moved continuously per se through that motion. For this is false. For, if an angel is posited to apply his power immediately to the whole heaven, it is clear that through that motion the angel does not change place, neither according to his whole self nor according to part, since the heaven itself according to its whole self does not change place: and consequently through such motion the angel is not moved locally. — If, however — which seems truer, and more conformable to the doctrine of Aristotle in VIII Physics ²⁶ — the angel moves the heaven by applying his power to parts succeeding one another in the east, then that motion of the angel is not continuous, but discrete. For he does not touch successively in such a way that he successively leaves the prior part, and successively reaches another part: but he applies his power to one part of some quantity, and leaving that whole part all at once, he is applied all at once to another whole part of the same quantity, or even a greater or lesser one, according as many parts arrive at the east. And thus, although the heaven is moved continuously, yet the angel himself, in moving the heaven, is moved not by a continuous motion, but by a discrete one. — But if an angel were posited as attached to a determinate part of the orb, and rotated with that part at the motion of the orb, then he would indeed be moved by that motion per accidens. And thus it would not be unfitting to say, according to what was said before, that he would be moved in common time. But we are speaking of his motion per se, not of his motion per accidens.

XII. For the evident understanding of the third doubt ²⁷, it must be considered first that, since motion is a certain transit from a term from which to a term to which; and this transit expresses nothing other than departure from one term and arrival at another: for any change to be in an instant or in time is nothing other than for the departure from one term and arrival at another itself to be measured by time, or by an instant. Whence, when it is asked, Whether the local motion of an angel is in an instant? nothing else is asked than, whether the transit of an angel from place to place, or, whether his departure from one place and arrival at another place, takes place in an instant.

2. It must be considered secondly, conformably to the doctrine of St. Thomas in IV Sent., d. xi, q. 1, 3°, quᵃ 2, ad 3, that when in some change a last to-be of the term from which is given, namely because some instant is given in which the movable is in it in such a way that immediately after that instant it will not be in it; and a first to-be of the term to which is also given, namely because some instant is given in which it is true to say the movable is now in that term and immediately before this it was not: then those two instants pertain to the change itself, or to that transit from term to term, one namely as the principle of its duration, and the other as its end. For when something transits from white through intermediate colors to black, the instant in which it was last under whiteness is the principle of such an alteration, while the instant in which it is first under black is its end: for it has neither another principle nor another intrinsic end of its duration. Whence each instant has two aspects: for the first is the end of the preceding rest, and the beginning of the following motion; but the second is the end of the preceding motion, and the principle of the following rest. — When, however, a last to-be of the term from which is not given, namely because a last instant in which the movable is under it is not given, the transit from one term to the other term does not include two instants, but only one, namely in which the movable is first under the term to which and first is not under the term from which: for in the whole preceding time it was in the term from which, and in that instant it first is not in it. Whence of that change, if it is taken per se alone, namely as it is distinguished from every other motion, the same instant is the principle and the end. And on account of this such changes are called instantaneous: namely because they begin and terminate in the same instant. This is evident in the generation of fire from air, which is posited as the term of the alteration ordered to the introduction of substantial form. For because throughout some whole time the matter is under the form of air, and a last instant in which it was under it is not given; but in the last instant of that time it is under the form of fire: therefore, taken with the preceding alteration set aside, the transit of matter from the form of air to the form of fire includes only one instant, in which is the principle and the end of the transit itself. And on account of this the substantial generation of fire is called an instantaneous change.

From this it appears to be necessary what St. Thomas frequently says, namely that instantaneous changes of this sort are terms of some motion. For if in the time preceding the instantaneous introduction of the substantial form into matter, the matter had been at rest under the preceding form, the preceding form could not in the last instant of that time be first cast off and the following first introduced, so that the principle and end of the change would be in the same instant. Because what is at rest in some whole time is in the same disposition in the last instant of that time in which it was in the whole preceding time. Whence it is necessary either that in the same instant matter be under both forms, which is utterly impossible: or that the movable was not at rest under the term from which in the time preceding that instant, but was moved from it through a greater approach to the term to which. And thus it is necessary that that sudden introduction of the term to which, and cessation of the term from which, follow upon some motion.

3. It must be considered thirdly, that while an angel is moved locally with a discontinuous motion, namely by touching several places successively according to their whole selves through several contacts; because every one of these contacts is instantaneous, as being measured by one instant of discrete time: it must be said that in such motion there is given a last instant in which he was in the place from which he departs, and there is also given a first instant in which he is in the term to which he arrives; for things that endure only throughout an instant have both their first to-be and their last to-be. But the discontinuous motion of an angel has this as proper, because it is measured by discrete time, in which one instant immediately succeeds another instant, that the term from which not only has a last instant of its to-be, but also has a first instant of its not-being: for in the instant in which the term to which first is, the term from which first is not. Which in things that endure through an instant of discrete time alone is not found: for although they have a last instant of their to-be, yet they do not have a first instant of their not-being. Therefore, as is clear from the preceding, the discrete motion of an angel does not include only one instant, but two, in one of which he is last in the place from which he departs, while in the other he is in the place to which he arrives. For for an angel to be moved locally is not for him to occupy one place, for this belongs to him even in the first instant in which he first touches the place: but it is to depart from one place and to arrive at another place, or to leave one place and occupy another; but this includes two instants in the motion of an angel.

4. From these things it follows that Capreolus wrongly concedes to Gregory, in II Sent., d. VI, q. 1, ²⁸ that an angel in the precisely same instant departs from the term a quo in which it is in the term ad quem. For if departure from the term a quo is taken as accompanying arrival at the term ad quem, it is clear that this departure is not in only one instant, but in two instants, in one of which it is said to depart through an affirmation about the present and a negation about the future, while in the other it is said to have departed through a negation about the present and an affirmation about the past. And thus such departure is in time: just as also in continuous motion departure from the term a quo, conjoined with arrival at the term ad quem throughout the entire motion, is not measured by any instant, but by the time measuring the motion. — But if by the name departure we wish to take only the first non-being of the term a quo, it would indeed be true that in the instant in which it is in the term ad quem, it departs: but this is improperly said; for an angel is not said to depart from the term a quo in the instant in which it first is in the term ad quem, but it is then said to have departed. — But if by departure from the term a quo is understood an instantaneous abandonment of the term a quo, it must rather be said that it departs in the instant in which it is in the term a quo itself, than in the instant in which it is in the term ad quem. For where a last being of the term a quo is given, departure from the term is through an affirmation about the present, not through a negation: as appears in all continuous motions. For when some body is moved from place to place, it is true to say that in the first instant of its motion it departs from the place in which it was according to its whole self; because it is true to say, "This body in this instant according to its whole self is in this place. And immediately after this, it will not be in it according to its whole self. Therefore it now departs from this place." But it is not said to depart in any instant in which it first is not: since that is not found. Similarly the same is found in the motion of alteration and other motions.

When, however, Gregory proves his thesis, ²⁹ when something simultaneously leaves a certain whole, it simultaneously leaves it and has left it: — it is said that this is true when that which is left has a first of its non-being, but not a last being, as when matter simultaneously leaves one substantial form and simultaneously receives another whole form: for then it is said to leave when it first is not in it. But it is not true where the thing which is left has a last of its being and a first of its non-being: because then it is first said to be left when it lastly is, but not when it first is not.

5. It must be considered, lastly, that since an instant means an indivisible of time, where several instants succeeding one another are found, there time is necessarily found: because there is the number of prior and posterior in motion, in which the notion of time consists. ³⁰ But this is found in one way in continuous time, and in another way in discrete time. For where there are several instants of continuous time, there time must necessarily be, not indeed constituted out of those instants as out of parts, but contained within those instants as within its terms: for all finite time is contained within two instants, just as also all continuous motion within two changed beings, or within two indivisibles of motion. Where, however, there are several instants of discrete time, there time must necessarily be, not indeed contained within those instants, but constituted out of those instants as out of its parts: for just as the discontinuous motion of an angel consists of indivisibles, so also does the time by which it is measured.

XIII. From these things it follows that St. Thomas, from the consideration of those things which are found in corporeal changes, cleverly, both in the First Part, q. LIII, and in I Sent., d. XXXVII, ³¹ and Quodlib. XI and IX, ³² concluded that the motion of an angel is not in an instant, but in time. For where, he says, ³³ there are several instants succeeding one another, there is necessarily time, since there is a numbering of prior and posterior in motion. But in the motion of an angel there are many instants succeeding one another. Therefore the motion of an angel is in time. — The minor is proved from what was said above. Because, namely, where a last being of the term a quo and a first being of the term ad quem are given, there must be several instants pertaining to the time measuring that motion, as has been shown.

To the reason brought forward to the contrary, ³⁴ however, it is answered that, if the local motion of an angel is said to be the occupation of one place in any way whatsoever, it is certainly conceded that it can be in an instant. For even if an angel had been nowhere, and began to operate in some place, it would be said to occupy a place in the instant by which its operation would be measured. And thus the major is conceded, and the whole argument. But this is an improper acceptance of local motion, nor do we accept the local motion of an angel in this way.

If, however, the local motion of an angel is called its passage from place to place, or departure from one place and arrival at another place, which is the proper acceptance of local motion, the assumed major is denied. For that the term a quo is left all at once and the term ad quem is acquired all at once does not suffice for the motion to be instantaneous: but besides this it is required that a last being of the term a quo is not given, as in substantial generation and in illumination it is not given. For if a mobile in one instant leaves the whole place through an affirmation about the present and a negation about the future, and in another instant simultaneously acquires the whole other place, this proves that the motion is discontinuous, but does not prove that it is in an instant: as is clear from the aforesaid.

To the proof it is said that being partly in the term a quo and partly in the term ad quem is required for continuous motion, but not for discrete motion, as we are now speaking of the motion of an angel. For concerning its continuous motion there is no doubt that it is in time.

XIV. Concerning the reason by which it is proved that effects made by corporeal substances through corporeal instruments are not miraculous, because namely bodies do not operate except naturally, ³⁵ a doubt arises. For either the term naturally is taken as it is distinguished against supernaturally, so that to operate naturally is the same as to operate according to the order of created nature: or as it is distinguished against voluntary, so that to operate naturally is the same as to operate from the necessity of nature, and not freely and from choice. In whatever way it is understood, someone could say that that reason is not sufficient. For if it is taken in the first way, it will be said that, although bodies do not operate except naturally insofar as they operate by their own power, they can nevertheless, insofar as they are instruments of an incorporeal agent, operate supernaturally, and consequently miraculously. — If, however, it is understood in the second way, it will be said that, although bodies do not operate except naturally, nothing nevertheless prevents them from being able to be an instrument of an incorporeal agent for working miracles. For God also sometimes operates miraculously through bodies as through instruments: as when at the touch of the bones of Elisha a corpse revived, as is found in IV Kings, chapter XIII. ³⁶

2. It is answered that here naturally is taken as it is distinguished against supernaturally, and outside the order of nature. For corporeal agents are said to operate naturally only because they operate according to the order and inclination of nature, and operate nothing outside the order of nature.

But it must be considered, from the doctrine of St. Thomas, De Potentia, q. VI, a. 3, that those things which occur by means of natural actions are not properly miracles: because those things alone are truly miracles which occur from a supernatural cause without natural actions. Hence, although some wondrous effects are produced by separated substances through natural corporeal powers, which corporeal power according to itself cannot produce, just as in the works of art we see some wondrous effects produced through certain instruments which the instruments themselves cannot produce per se: those effects nevertheless are not miracles, because they occur by means of the action of a natural power.

It must be considered further that a body can be understood to be an instrument of an incorporeal agent in two ways: in one way, by the action of its own power cooperating toward its effect; in another way, by only conveying the power of the incorporeal agent, and presenting it to the matter in which the effect is produced. In the first way, a body properly has the nature of an instrument, but not in the second way (although even thus it can in some way be called an instrument): since, as is said in the First Part, q. XLV, a. 5, an instrumental cause does not participate in the action of the principal cause except insofar as through something proper to itself it operates dispositively toward the effect of the principal agent.

3. When, therefore, it is said that bodies can operate outside the order of nature insofar as they are instruments of an incorporeal agent: it is denied, speaking of a created incorporeal agent. For a body cannot be an instrument of this incorporeal agent for acting to produce any effect in these lower things except in the first way only. Because, as St. Thomas holds in the following chapter, and in many other places, separated substances cannot transmute corporeal matter to a form except by means of natural actions: when, however, something is done by an incorporeal agent by means of the natural action of a corporeal agent, that is not outside the order of nature, even if it could not be done by corporeal agents alone. For the order of nature has it that something may be done through corporeal action insofar as an incorporeal agent uses it, which could not be done without an incorporeal agent: just as through an instrument, insofar as it acts in the power of the principal agent, something can be done beyond the power of the instrument absolutely considered; for a bed is made by the power of art through a saw, which would not be made by the power of the saw alone.

4. When it is said secondly, that God sometimes operates miraculously through bodies: — this is certainly conceded: because God sometimes uses a body as conveying his command to things, as can be found in De Potentia, the cited question, a. 4, and IIª IIae, q. CLXXVIII, a. 1, ³⁷ by which command alone he operates miraculously. But he does not use a body as a co-agent through the action of its own power for a miraculous work. And if God were to effect something in things by means of the action of nature, that would not be a miracle: as if he were to heal someone through the application of a natural medicine. But it is not thus with a created incorporeal agent, as has been said.

XV. In the second place St. Thomas proves the other exponent, namely: God can work miracles. ³⁸

He proves it, however, through the opposed conditions made in the above reasons. Because, namely, he is above the order of the universe, inasmuch as from his providence this whole order flows: the opposite of which was said of a creature in the first reason. And because his power, inasmuch as it is infinite, is not determined to any special effect, or to any determinate mode or order of producing: the opposite of which was said in the other reasons concerning created power.