Disputationes metaphysicae

1. It remains to say whether at least dividedly the same effect can be made by several total causes, which is to ask whether the light which here and now is produced in this air by this lamp applied in this place would be produced the same in number by another lamp distinct in number, yet wholly like in power of acting, if it had been applied to the same air at the same time and place; and so of the other effects. In which matter there is no controversy about the absolute power of God; for so no one that I have seen denies that God can make through one natural cause the same effect in number which He makes through another; although this too needs declaration in the opinion of those who deny that this can be done naturally, if they are to speak consistently, as I shall declare below.

The former, negative opinion

2. The disputation, then, is of the natural power of causes, and in this way many deny that one natural cause can effect the same effect in number which another makes, even if it were applied to the same patient with the same conditions. Which opinion St. Thomas signifies, Quodl. V, a. 8; and Capreolus, In II, dist. 20, q. 1; and Marsilius holds it, I De Generat., q. 8; and Soto, In IV, dist. 34, q. 1, a. 3. And it is the opinion of the Commentator, in VII Metaph., comm. 31.

3. The first reason for the reported opinion.—Various reasons are adduced. The first is that, when this effect is produced such in the individual, some proximate natural cause must be given why such individual is produced rather than another; but this can be none except because such effect is produced by this singular cause, not that it alone is the adequate reason of the production of such effect in the individual, but that without it the adequate reason cannot consist; for this is enough for this effect in number not to be able to be produced except by this cause in number. The inference is clear; but the antecedent can be proved by running through all things which can contribute to the production of this individual effect. Because neither does this subject suffice, because it is indifferent to several forms, nor time, place, etc., both on account of the same cause and because they are very extrinsic, as was treated at length above, disp. V.

4. It is refuted.—But this reason in our opinion has no force, for if the discourse is of the intrinsic notion of the individuation of the effect, we already said above that it is placed in the intrinsic principles themselves of the thing or in its proper entity. But if the discourse is of the reason on account of which the agent is determined to this effect in number, the reason is not rightly given because it is this agent, for this agent too is powerful and of itself indifferent to producing several effects distinct in number. But if it is said that this particular agent is not indifferent to producing several effects distinct in number here and now about this subject, but is determined to one, the cause of this determination still remains to be inquired, which is not sufficiently given from the individuation of the cause, because that per se is powerful for several; nor yet from the other adjoined circumstances, as I proved in the said place, because either they too are indifferent, and from many indifferent things one determined principle is not made; or they are very extrinsic, as extrinsic time or place. On account of which we thought it more probable that the secondary cause is determined as to this from the concurrence of the first; but this determination on the part of the first cause can be made as well with this individual cause as with another like one distinct in number in order to the same effect in number, as I shall show a little below; therefore from this head it is not proved that for this singular effect this singular secondary cause is necessary. But Soto objects (who chiefly magnifies this first reason) that it is not philosophical to bring back this determination to the first cause, because the first cause of itself does not concur except by general and indifferent influx. But this is proved by him by no reason, nor is it true, as is established from what was said above about the concurrence of God; and it is more consonant with the perfection of divine providence that God by His will decree which individuals are to come from all causes.

5. A second reason is wont to be given, because, if this effect in number could have been produced by another cause distinct in number, it would not depend per se and essentially on this singular cause by which it is now produced, and consequently such cause would not be the per se cause of this effect, but only per accidens, because the effect depends per se and essentially on the per se cause. But the discourse was supposed to be of the per se cause; therefore, in order that the per se order between cause and effect be saved, it is necessary to say that the singular effect which is made by this cause in number cannot naturally be made by another distinct in number. The first sequel is proved, because, if in place of this cause another distinct in number had been applied, the same effect in number would have been produced by it; therefore it is per accidens that this effect is produced by this cause. And it is confirmed, first, for every determinate and singular effect by its nature demands a determinate per se cause by which it is made, because it depends per se on some one; therefore it cannot naturally be made except by it. And it is confirmed, secondly, because this action in number which is made by this total cause cannot be made by another distinct in number; but this action in number tends to this effect in number, and actions distinct in number to effects distinct in number; therefore this effect too which is made by this cause cannot be made by another like one and of the same order and distinct in number.

6. It is disproved.—But neither are all these things efficacious for persuading the opinion. And indeed in the principal reason two terms are to be distinguished, to depend per se or essentially; for they are not equivalent, but to depend essentially is more than per se; for in order that the effect depend per se on the cause, it is enough that it truly and properly receive its being from it, because to receive being and to depend are almost the same. But to depend essentially adds that the effect from its intrinsic nature and essence demands the influx of such cause, so that without it it cannot be; which is sufficiently proved from the signification of that word, essential dependence. When, then, it is inferred that, if this effect in number could be produced by another total cause of the same order, it follows that it does not depend per se and essentially on this cause by which it is now produced, since the consequent is twofold, a twofold answer too must be applied, and the former part of the sequel denied and the latter granted.

7. I deny, then, that it follows that the effect does not depend per se, because it depends on a cause properly and per se inflowing being into it. Nor does it matter that it could be made by another, because in fact it is not made by another, but by this alone in the order of causes; therefore that is enough for it to depend on it as on a total cause. But when it is pressed that another could be applied, and so it is per accidens that it is made by this one, it is answered that there is an equivocation in that term per accidens, because it is no longer taken as it is opposed to the per se cause, but as it is opposed to the simply necessary or unique cause. I grant, then, that with respect to the effect it is per accidens, that is, contingent and outside its essence and beside its notion, that it is made by this cause in number rather than by another. Likewise on the part of the cause it can be called per accidens that this cause rather than another is applied, because either it is not applied by itself but by another, or because this is accidental and contingent with respect to it. But all these are remote and extrinsic to per se causality, because already in that instant in which this cause is applied it truly and properly inflows being into this effect, and this is enough both for it to be a per se cause and for the effect to depend per se on it. Just as also this cause, here and now applied to this patient, could induce not this form but another in number, and for this reason it can be called per accidens with respect to it that it makes this in number rather than another, because it is extrinsic and accidental that God defined concurrence to this effect rather than to another. Nevertheless, already so applied, it per se makes this effect; so, then, the effect too here and now depends per se on this cause by which it is properly made, even if it could be made by another. But the other part of the sequel rightly follows and is to be granted, namely, that such effect does not depend essentially on such cause; and that consequent is most true. Indeed, as is established from what was said above about the concurrence of the first cause, no effect depends essentially on a univocal cause; indeed no created effect, inasmuch as it is from the efficient cause, depends essentially on a created cause, but on God alone, because it can be made by Him alone without any other, but by the others it cannot be made without Him.

8. But if it is said that this is true taking that word essentially in its rigorous signification, but that here it is not so taken, but as it is the same as connaturally, and in this way a created effect can depend on a created cause and a univocal on a univocal, and so one effect has only one cause on which it connaturally depends, I answer that it is indeed true that actually one effect depends only on one total cause of one order by connatural dependence; but I deny that one effect in number can depend only on one cause in number, because if it were made by another like one, it would depend on it as connaturally as on the other.

9. Hence to the first confirmation I absolutely deny the antecedent, because this effect in number, if its individual nature and entity is considered absolutely, does not determine nor necessarily demand (namely by connatural and intrinsic necessity) to be made by this cause in number and not by another; or at least this is proved there by no reason, because this thing by its nature only demands to be made by something having sufficient power to make it. But if several agents have had that power, it matters nothing to the nature of such effect, nor does anything prevent it from being made per se by whichever happens to be applied, as has been declared.

10. To the second confirmation, I grant that this action in number can only be from this agent and to this terminus. But I deny that actions distinct in number necessarily terminate at effects distinct in number; for that this is not necessary has often been proved in the foregoing; otherwise not even by absolute power could the effect which is made by one agent be made by another distinct in number, even dividedly, because the action of one cannot be made by another. But if it is said that actions distinct in number tend by natural necessity indeed to effects distinct in number, yet not by absolute necessity and in order to the divine power, against this is that that natural necessity has been proved by no reason. For when several agents concur at once, there is some necessity or at least natural congruity that they act on the same effect by one rather than by two actions. But that diverse agents, total as to power of acting, cannot have their own proper distinct actions about some effect, so that each can by itself effect it, at least when it is applied alone and without the other, has so far been shown by no reason. There is no reason, then, why it should be necessary by natural necessity that one effect can naturally be made only by one individual and particular action, even dividedly.

The second opinion, contrary to the preceding

11. The foundation.—Because, then, more efficacious reasons have not so far been found for confirming that opinion, it has not been approved by other authors, but they say that the same effect in number can be made dividedly by diverse total causes, and that now indeed this light is made in this air by this lamp, because this one has been applied; yet that the same would nevertheless have been going to be if another lamp had been applied. Scotus holds this opinion, In II, dist. 20, q. 2, which is proved by him by a philosophical and a theological argument. The theological argument is that God, before original sin was foreseen, elected to glory these singular men whom He predestined, of whom many are now generated by reprobate men; but if Adam had not sinned, they would be generated by other men distinct in number, because then there would be no reprobate by whom they would be generated. But this argument inculcates many things which are to be passed over by us, lest we transgress the metaphysical bounds. Yet in truth the reason is not efficacious, and, besides many uncertain things which it supposes, this is certain with me, that God elected the predestined with at least conditional foreknowledge of the fall of the human race, which is enough for Him to have been able to will at the same time that these predestined be generated by these parents in number. But if God had foreseen, even in conditional knowledge, that Adam was not going to sin, either He would not have had the decree of electing these men whom He now elected, or He would have elected together with them the parents of those whom He now elected, or certainly He would also then have permitted some to be reprobate. For it is not true, or at least not certain, that if Adam had not sinned no other men would have sinned or been damned. Thus (that we may omit these things) it is certain that on account of the certitude of predestination it is not necessary to say that one man can naturally be generated by other parents than by those by whom he is in fact generated.

12. The physical reason is that two agents of the same species are of equal power; therefore whatever one can effect from such matter here and now applied to it, the other can effect; otherwise they would not be of equal power; therefore the effect which is made by one could be made the same in number by the other. But neither is this reason convincing; for from equality of power only equality of the effect can be gathered, not identity; for, just as in the power itself it is one thing to be equal, another to be the same, so also in the effect. It is easily answered, then, that equal power can from the same matter effect an equal effect, yet not the same. Other reasons too are wont to be made in favour of this opinion, which seem to me lighter and therefore I omit them.

The point of difficulty is opened

13. In order, then, that the point of controversy be attained, one must insist on seeing whether an effect contained under the object of one active power can be contained under the object of another, and whether this can be defined with certain reason on either side. In which is to be noted the difference between the particular and univocal cause and the equivocal and universal, that the universal, because it contains the effect not formally but eminently, can per se regard the whole species and all the individuals contained under it. And hence I think it certain that the same effect in number which is made by a particular and univocal cause can be made in a connatural way by an equivocal cause as total and proximate cause, if, without the intervention of the univocal cause, the equivocal cause alone, and of itself universal, is applied to generating such effect immediately and by itself alone. This is most certain in the most universal and most eminent cause, which is God, for by this reason He can make by His power any effect which secondary causes can. I think the same of the heavenly powers as to those effects which they truly contain eminently and as per se sufficient causes. As, for example, if the sun is a sufficient cause for generating gold or fire, so far as concerns itself it is sufficient for any individual of gold or fire, because its power, being more eminent, adequately regards that whole species, and therefore, so far as concerns itself, it can effect it in any individual.

14. An equivocal cause can effect the same effect in number which an inferior would effect.—As to these causes, then, no reason appears why it should be denied that the effect produced by fire, for example, in this wood could be produced the same in number by the sun, if it were sufficiently applied to the same patient and with the other circumstances. In which we do not properly compare the particular cause to the universal, inasmuch as that is called a universal cause which operates with another particular one, but we compare two particular and proximate causes operating through diverse powers, namely formal or eminent. From which it is also understood by the way that the reason is far diverse of total causes operating conjointly or dividedly, for two total causes of this kind which operate as particular and proximate causes cannot conjointly and at once effect the same effect in number by their own proper and distinct total actions, even if one is equivocal, the other univocal; for the reason and resolution made in the preceding point proceed equally in these; but dividedly the same effect can very well proceed from either of these causes, as has been said and declared.

15. The univocal cause does not have its whole species as adequate object.—But the univocal cause cannot have as the adequate object of its active power the whole species of such effect, as St. Thomas noted, I, q. 45, a. 5, ad 1, because otherwise such cause would enclose itself under the object of its natural power, which is impossible; otherwise it could produce itself. Nor yet is it enough if someone answers that, so far as concerns the power, it can produce itself, yet from another side it is repugnant that that power be reduced to act with respect to itself, because for acting the cause itself is necessarily supposed already produced. This (I say) does not satisfy, because efficiency from its intrinsic nature regards a distinct thing; therefore also the power of effecting by its nature has as object only a thing distinct from itself; therefore it in no way contains itself under its adequate object, and therefore the univocal cause cannot regard its species as the adequate object of its power. Which reason does not proceed in the equivocal cause, for, although this adequately regards some whole species, it is not reflected upon itself, because it itself is not an individual of that species, but of a higher order. Hence, then, a doubt arises, how widely the object of the univocal active power extends; for since it is not the whole species, nor only one individual of that species, as is per se established, it must be several individuals of that species; how many, then, will those be, or what rule is to be kept in assigning the adequate object of such power? In which all agree that a finite number of individuals cannot be designated, because the active power, so far as concerns itself, if it is not corrupted or impaired, can always produce another and another individual. Hence it can be said to be of itself indifferent to infinite individuals syncategorematically, successively or disjunctively. Yet this very infinite multitude can be understood in various ways; but there are chiefly two which pertain to the present matter.

Various modes of assigning the adequate object to the active power of the univocal agent

16. The first.—One is if we say that such cause can effect any individual of its species outside itself. And no improbable reason can be given, for about itself it cannot have efficiency on account of identity; but if this impediment were removed, there would be no drawback in such power having as adequate object that whole species; therefore, since this reason ceases about all the other individuals of the same species, because all others are distinct from this agent in number, it is likely that any individual of such species encloses under the adequate object of its active power all the individuals of the same species other than itself. But if this mode is true, it evidently follows that two total causes of the same species can dividedly effect the same effect in number. Indeed, rather it follows that no effect can be made by one which cannot be made by the other, themselves reciprocally excepted, for any one can effect the other, but not itself. Hence further it also follows that any univocal cause, so far as concerns its power, has force for effecting that individual by which it itself was begotten, as that Peter, for example, has power for generating his parent or also his grandfather and any progenitor of his, so far as concerns the force of the active power; which can seem the greatest drawback of all which can be thought of in this mode of speaking. Nor can it be denied that it follows, for all those individuals are comprehended under the adequate object of such power, as is supposed; therefore, so far as concerns the force of the active power, and per se speaking, it could produce any of them. But it can easily be denied that this is a drawback. For in fact this thing in number cannot effect those individuals from which it itself proceeded and was made, because those individuals preceded in being and were produced by other causes; yet, if they were considered according to themselves and no repugnant condition were presupposed, nothing would prevent those individuals which are now causes of others from being their effects, and conversely.

17. The second mode.—Another mode of explaining the adequate object of this power is if we say that the single active powers of the single agents determine for themselves certain individuals of their species which alone they can effect, and conversely that that whole series of individuals determines for itself from its nature such univocal cause by which they can be made, and not by another within that species. Which series of individuals proceeds indeed to infinity, yet nevertheless contains only a peculiar order or flock (so to speak) of individuals saying of themselves relation to such cause; which orders of individuals can be multiplied to infinity within the same species, for within one species there can be not only infinite individuals, but also infinitely infinite and infinite series of individuals, which all contain distinct individuals and in each one proceeds to infinity. And according to this mode it openly follows that the singular effect which is made by one univocal cause cannot be made by another, because the individuals contained under the object of one power are not contained under the object of the other.

18. What difficulties weaken this mode of resolving the question.—But I do not see a sufficient reason which can be given on the part of such causes why they so determine their objects and each tends to its proper collection of distinct individuals, but it can only be affirmed that by reason of its individuation each is so determined in acting. As the intellect of Peter, for example, is by its nature determined to effecting such acts of understanding in number as no other intellect distinct in number can effect; and the same holds of the single intellects; for in this way that opinion explained in the said mode philosophizes. Yet in truth the reason is not the same of the powers which elicit immanent acts and of those which effect in exterior matter, for in the former powers each is determined to effecting only in itself and from itself, for this is of the intrinsic notion of the immanent act; and because in diverse subjects diverse acts distinct in number are found, therefore each of these powers is determined by its nature to acts distinct from the acts of the other. But the power which acts in external matter does not determine for itself a certain subject in which it acts; and therefore agents distinct in number can act in the same patient in number, either at diverse times, or at the same, either conjoined as partial causes, or dividedly as total; and therefore there is not in them the same reason on account of which they are determined to effecting forms distinct in number, even with respect to the same patient.

19. Wherefore on the part of the cause no probable cause of this determination occurs; for certainly the individuation alone of the cause itself is not a sufficient reason for it to be determined to effecting these individuals rather than others; nor yet for causes distinct in number to be determined to individuals distinct in number. Otherwise with the same facility someone could say that the individual cause by virtue of its individuation is determined to effecting only one individual, especially from the same subject, as the univocal cause of one species is determined to making an effect of one species only. But on the part of the effect the reason touched upon above can be given, because one effect by its nature demands one determinate cause by which it is made, because, since the effect has natural dependence on the cause, the singular effect too has natural dependence on a singular cause; and therefore the power itself too encloses under its object only those effects which can naturally depend on it.

20. The first reason of difficulty.—But this principle too, which is taken from the effect, I do not see by what sufficient reason it can be proved; and from elsewhere vehement conjectures occur on account of which it does not seem to be admitted. First, because the dependence of the effect on the univocal cause is accidental, since it is only in becoming and is separable from the thing itself; but there is no reason on account of which this individual thing should by its nature determine such accident; as, then, the same subject is indifferent to several heats distinct in number and naturally receives that which the agent first occurring can effect, so the same effect is indifferent to dependences accidental to it, although, while it is made, it is made naturally and per se through the dependence which can be from that agent which is then applied.

21. The second.—Secondly this is declared further, because, if the entity of the effect itself is considered, it is absolute, that is, not including in itself a respect, even transcendental, to some univocal agent, because, since it does not depend on it essentially and in its being, there is no source from which it should include in itself such respect; therefore such effect by virtue of its entity does not demand dependence on this cause in number as more connatural to itself than on another.

22. The third.—Thirdly, the same effect in number which is made by a univocal cause can be made per se and connaturally by an equivocal cause, not only the first, but also a secondary and created one, if it eminently contains such inferior species, as we said and proved a little before; therefore, the comparison being made between those two causes, univocal and equivocal, that singular effect does not more determine for itself by its nature emanation from one than from the other; for it can be made equally indifferently by whichever of them has first been sufficiently applied; therefore, the comparison being made between univocal causes, there is no reason why that effect should determine for itself by its nature emanation from one of them only, but it can be produced indifferently by many, or by any like one. The consequence is evident, both because, if it were connatural to every effect to determine for itself only one cause, it would have to determine simply one, either univocal or equivocal, at least among created ones. And also because the reason which seems to have moved other authors to say that one singular effect has natural dependence on one singular cause, namely, that it may seem to be produced by it per se and not per accidens, this (I say) reason can equally be applied to the univocal and the equivocal cause, because it too could be said to be produced per accidens by either of them, since it could equally well be made by the other, if it had been applied; but if this does not impede the per se causality of that cause which in fact is applied, whether it be univocal or equivocal, it does not impede it in univocal causes either, whether this one in number is applied or another. But if someone says that the reason is unequal in the equivocal cause, since it eminently contains the whole species and consequently all its individuals, it is answered that this does not matter to the present reason, in which we consider the determination or indifference on the part of the effect, not on the part of the cause. But if the effect by its nature were determined to depending only on one singular cause, it could not be contained virtually in several causes; but if on the part of the effect there is not this determination, then neither on its part is it repugnant to be contained in many causes and to be able to depend on each; therefore there is no reason why this should be more true with respect to the univocal and equivocal cause than with respect to univocal causes. Most of all if both the first and the second comparison are made to created causes; for, although the univocal cause does not contain the whole species as the equivocal does, yet it can virtually contain any individuals like itself and distinct from itself.

23. Fourthly, we can at the same time take a similar reason from the fact that one effect in number can dividedly depend on two total equivocal causes, even created, distinct either in species or in number, for each of them contains eminently the whole species of the inferior effect; hence, so far as concerns itself, it is powerful for effecting any individual of that species; and consequently every individual which can be made by one of those causes can be made by the other; therefore the same can be in univocal causes. The consequence is evident from what was said above, because that is a sufficient indication on the part of the effect that it is not repugnant that it can naturally depend on this or that cause; nor can a reason be assigned why on its part it should be more repugnant in order to univocal causes than to equivocal ones. But if on the part of the effect there is no repugnance, in truth on the part of the causes none can be assigned.

24. And in this way another reason which can be made here has force, that the same effect in number is made by one cause and conserved by another; for this has no place in the univocal cause, for its effect does not depend on it in being conserved, per se speaking; for when it is said to conserve in the wood the heat which it produced, it is not understood of conservation directly and per se, but per accidens, by defending from contraries; and therefore it is no wonder that such conservation, or rather defence, can be made by any agent of like power. But in equivocal causes it seems certain that the effect produced by one can be conserved by another, as the light of this air made by this lamp is conserved by another sufficiently applied, even if this one is at once extinguished. For it is not likely that a sudden and insensible change of light takes place; therefore by the same reason one lamp could have effected from the beginning the same light which the other made, if it had been applied, both because conservation of this kind is true efficiency and of itself and by its nature could be production; and also because, unless this light were contained under the object of the other lamp, it could not naturally be conserved by it; but if it is contained, it can also be made.

25. But from univocal causes some sort of argument can be taken from the fact that one can intensify the same quality in number which another began; therefore it can also begin or effect it; for it is wonderful to say that one and the same quality according to diverse grades determines for itself diverse natural agents otherwise wholly like among themselves. Finally it does not seem likely that one angel cannot effect in the same body the same local motion in number, or the same intrinsic Ubi, which another would effect, if it had moved it at the same time. And therefore in this example the authors of the contrary opinion too admit that the same effect in number can be made by diverse total causes disjunctively; but they deny that a sufficient argument is taken thence to other effects, because through local motion no new absolute entity is made in the mobile. But this answer does not satisfy, both because, although through local motion no new absolute thing distinct from the mobile is made, yet a real absolute mode, distinct from the mobile from the nature of the thing, is made, from which no light argument is taken to the effect which is a distinct form. And most of all because, even with respect to local motion and Ubi, true efficient causality and per se dependence of this effect on this cause intervene; therefore, if this does not prevent such effect from being able to be made by another cause distinct in number, neither will it prevent it in effects which are distinct things or forms. It is true that this example too proceeds of equivocal causes, because in local motion the mover is always an equivocal cause; yet we have already shown that a sufficient argument is taken from equivocal causes to univocal ones.

Affirmative resolution of the whole question

26. The reasons of each side, then, being weighed, although neither wholly compels or demonstrates, yet these latter bear greater likelihood. Wherefore, speaking in general, I think it must be said that it is not repugnant that the same effect in number depend on several proximate and total causes disjunctively, or conversely (and it comes back to the same), that several causes can have power such that each can per se effect the same effect in number, which is more certain if both or one is an equivocal cause; yet it is also more probable in univocal causes. Some things, however, must be observed. First, it must be supposed that the effect is either equal or inferior to the cause; which I note for this reason, because, if the opinion were true which affirms that individuals of the same species can be unequal in perfection, it would not be necessary that any individual cause in some species could effect all other individuals of the same species by its own power, but only those which were proportioned or equal to it. Next, one must speak of effects wholly alike in the individual, as are two heats of the same subject; for if effects, although they are of the same species, are not wholly alike, but (so to speak) in some way heterogeneous individually, it can happen that on account of the peculiar condition which the single individuals have, they determine for themselves only one natural cause of one order, which can happen not only in univocal causes, but also in equivocal ones. As, for example, the visible species of Peter and of Paul are of the same species (for I suppose each is white), and nevertheless neither can Peter effect the species of Paul nor Paul that of Peter, because those species, although they are alike in specific nature, yet from their individuation have proper relations to distinct objects, and therefore I call those species unlike and as it were heterogeneous individually, and those objects, although they are in their way equivocal causes of such species, yet do not have eminent power for the whole species, but each for those species only which represent it. Something similar can be observed in immanent acts, as we said above; and the same holds of habits. Thus, where a peculiar reason or determination intervenes, it can happen that a cause is determined to some individuals of one species and cannot be to all; and thence too it can come about that the effect which is made by one cause cannot be made by another distinct in number; absolutely, however, it is not repugnant to the natures of things.

27. Finally it must be observed that so far we have explained only what can be done by virtue of particular causes, not what is done; for that is much more uncertain to us, so that it cannot be defined by any reason. For, although two particular causes have power for effecting the same effect in number, yet the actual determination of such cause to making this individual rather than another depends on the first cause as on the primary origin of such determination; and therefore, although this cause now applied effects this singular effect, to which it is determined by the first cause, whether, if another like one had been applied in its stead at the same time and place and about the same subject, it would have made the same effect in number, is not established to us. Not because it is not in that power, which we have so far treated, but because that power too is indifferent to several individuals and we do not know whether in that case it would be determined by the first cause to making the same individual in number; we affirm only, then, that it can be so determined, but that the actual determination depends on the concurrence and will of the first cause.

The arguments of the second opinion left over from the preceding section are satisfied

28. From these too must be answered that question which was made in the foundations of the second principal opinion adduced at the beginning of the preceding section, namely, what two causes total in power or in first act would do, if they were applied at once and equally to the same patient and were left to act according to their nature. For one must distinguish, for either those two causes would be applied at once and in the same instant, or one prior in time to the other. Again, either the patient is capable of several effects distinct in number, or of one only. Next, if the effect is one, it can be indivisible, as is the substantial form, or having latitude of dimensions; likewise it can depend on the cause only in becoming, or also in being conserved. First, then, if the causes are applied at once and the patient is capable of several effects, they will effect them, and each its own, and so all controversy ceases; for in this way two white objects equally applied will effect two intentional species. For in this example those two causes neither are nor can be total causes of the same effect in number, because neither object can make the species of the other. Hence I do not think an example can be found in which each cause can be total with respect to each effect, and yet the patient can receive both at once, because two forms or accidents distinct in number alone and wholly alike cannot be at once in the same subject. But if this is admitted according to the opinion positing several lights in the same air, it could also be said that then those causes would operate as total causes, yet not both the same effect, but each its own. Although this too would be uncertain; for it depends on the determination of the first cause, which could give concurrence either to diverse effects in number or only to one and the same; yet, since those causes from that hypothesis are then apt to operate as total causes, it is likely that they would receive the natural concurrence to operate so, and consequently would effect diverse effects in number.

29. But supposing that the subject is capable of only one form, then those causes applied at once would effect the same effect at once, yet not as total causes, but as partial; not because that effect the same in number could not be made by each of those causes, nor by either of them alone, but by both together partially; for it is incredible that some natural effect should by its nature determinately demand for itself this mode of dependence on many causes at once, to which it is per accidens to be so conjoined for operating. The reason, then, is only that that mode of acting is then more consonant with the natures of things, as was declared above. But if the effect is indivisible, it cannot be more perfect on account of the conjunction of two causes; but if it is capable of greater or less intensity, sometimes it will be more intense, namely, when neither of those causes by itself alone could have operated according to the whole latitude of its intensity or activity, either on account of distance, or on account of the resistance of the patient,¹ or on account of a peculiar property of its nature; in which way we experience that two lamps equal among themselves effect together a more intense light in the air than each could effect by itself.

30. But if one of such causes is applied prior in time to the other, it will at once effect the whole effect which it can effect at that time or instant; and then it is more uncertain what the other cause supervening effects. And indeed, if the effect does not depend in being conserved, but only in becoming, and is indivisible or already wholly produced, it is clear that the posterior cause can effect nothing, because it already finds it made, and because the other cause already does nothing, but has done. But if the effect depends in being conserved, some say that the effect which had been made by the prior cause will perish, and that a new one will be produced by those two at once and conserved for the future. But that is incredible, because there is no cause there why the prior effect should be corrupted, nor yet is it consonant with nature that God should suspend the concurrence by which He conserves it, no corrupting cause supervening.

31. Others say more probably that from that instant in which the posterior cause is applied that effect begins to be conserved by two causes at once, which before was conserved by one only, because it ought not to be idle, since it can operate for this. But this too has difficulty, because either that effect begins to be conserved by the posterior cause through a new action which flows from it alone, the prior cause also persevering in its action; and so it follows that that effect is conserved by those two causes at once as total causes; which we do not admit; or the prior cause desists from its proper action, and both causes begin to have a new common action by which they conserve the same effect; and this too is difficult, because there is nothing which compels the prior cause to remit its influx or to desist from the prior action. Nor can this be reduced to the determination of the first cause varying its concurrence and the determination of the action of the secondary cause, because it is not due to the supervening cause that the action or concurrence be changed in order that it can do something. Wherefore it is probable that in that case the posterior cause will effect nothing, because it finds made whatever it could make.

32. But if that effect were intensifiable and had not been produced according to the whole latitude of such causes, then the posterior cause would effect its intensification. But this could be understood in two ways: first, that the first cause would precisely persevere in the prior action, but the posterior would add so many grades of quality; and then each would be the total cause of some part (so to speak) or of some grades of that effect; but each would be a partial cause with respect to the whole effect, by partiality, as they say, not only on the part of the cause, but also on the part of the effect. In which mode of speaking it is only difficult, since those agents are like and equal, as we suppose, why that greater intensity should be made by the posterior agent alone, since that action of greater intensity seems in some way more perfect. For neither can it be said that the prior cause both conserves the whole action which it was effecting before and helps the supervening cause to the intensification of such effect, because by the prior action it was acting as much as it could, therefore it cannot act anything further unless it remits something of the prior action. And therefore it is probable that in that case the prior cause ceases from the action which it was totally exercising and is conjoined to the posterior, so that both together both conserve the effect and render it more intense. And so far about efficient causes.

Brief resolution about the concurrence of several final causes

33. Finally it is easily established from what has been said what is to be said of final causes; for in them the resolution is much easier. For if the discourse is of the intrinsic end, that can only be one with respect to one action, because both one action can have only one total terminus, and nature intrinsically and of itself always tends to one. But if the discourse is of the extrinsic end, which the free operator intends at his choice, either it is only proximate or particular, or it is the end simply ultimate and universal. When it is of the former mode, nothing is repugnant in there being several final and total causes of the same action, as is established by experience; for someone can give alms both in order to satisfy for sins and in order to honour God and to help his neighbour, so intending all these that for the sake of each he has an absolute will of doing that work. And the reason is that, when the end is so extrinsic with respect to the action or effect, it does not add intrinsic entity or real mode, but only subordination to the extrinsic intention or will of the agent, and therefore there is no drawback that in this way the same action proceed from many total ends. It is true that, if they are compared not to the external action but to the internal act of the created will, then two ends of the same notion, that is, equally proximate, cannot be total causes of wholly the same act, because with respect to the interior act they have the notion of object, if they are proximate ends; but one and the same internal act cannot tend to several total objects. And the reason is that with respect to interior acts such ends are not extrinsic, but intrinsic, since they are their proper and formal objects, but we have spoken of extrinsic ends; of which matter can be seen what we wrote in tome I of the III Part, disp. V, sect. 3. But if the ends are simply ultimate with respect to the operator, there cannot be several total with respect to the same, even from the intention of the operator himself, because it is of the notion of the end so ultimate that all things be referred to it, and therefore it is repugnant that it be multiplied, of which matter many things are disputed by the theologians, in I-II, q. 1, a. 5.