Disputationes metaphysicae

1. That there is a cause is by far the best known.—We do not inquire whether there is a cause, because nothing is more self-evident; but for investigating what it is, we fittingly take our beginning from the notion of principle, since every cause is a principle and can and must be defined through it as through a genus, or in place of a genus. The reason for doubting, then, in the proposed question is taken from various sayings of Aristotle; for sometimes he signifies that cause and principle are altogether the same and are said reciprocally. For in Metaphysics IV, c. 2, he says that cause and principle are so compared among themselves as being and one; but being and one are convertible among themselves, as was said above. Likewise Metaphysics V, c. 1, where he enumerates the various modes of principle, at the end he so concludes: In as many ways too are causes said, for all causes are principles. Again, when in Physics I he had numbered privation among the principles of the natural thing, in Metaphysics XII, c. 2, he calls it a cause; he thinks, therefore, that cause and principle are the same; and the manner of speaking of some Greek Fathers favours this opinion, who also in the divine persons call the Father the cause of the Son because he is his principle; and similarly the Father and the Son the cause of the Holy Spirit, which is an indication that among the Greeks cause is the same as principle.¹ Which the Council of Florence signified in expounding those Fathers, last session. But the reason can be that a principle expresses a relation to what is from the principle as a cause to its effect; but what is from the principle seems to be the same as the effect.

2. But sometimes Aristotle seems to signify that cause extends more widely than principle; for he says, De generatione animalium V, c. 7, that it is of the notion of principle that it itself indeed be the cause of many, but that there be no superior cause of it; but it is not of the notion of cause that it not have a superior cause; therefore, according to Aristotle’s opinion, principle is something more contracted than cause. Whence also Physics I, c. 5, he says of the notion of principles that they be neither from themselves nor from others, but others from them; but it is not of the notion of cause that it not be from principles and causes; cause, therefore, extends more widely than principle. Finally, from elsewhere it appears manifest that principle is something more general than cause; for every cause is a principle, as we reported from Aristotle; yet not every principle can be called a cause; for privation, on the testimony of Aristotle, is a principle of generation, yet not a cause; and the dawn is the principle of the day and not a cause. And among the theologians it is sound and received doctrine that in the divine persons one is the principle of another, yet not the cause, as is evident from St. Thomas, I, q. 33, a. 1, ad 1.

The various modes of principles and their order

3. What the complex principle, or principle of knowledge, is.—In order to explain this question, one must begin from the name and notion of principle; but since, as Damascene says, Dialogue against the Manichees, at the beginning, the word principle is equivocal, that is, analogous, it will be better to enumerate its various significations, which Damascene recounts there, and before him Aristotle, Metaphysics V, c. 1. But in order that they may be handed down by us with some certain method, we can first distinguish a twofold principle, one of the thing, the other of knowledge or of science; which in another way is wont to be distinguished into incomplex and complex principles; for the principle of the thing is incomplex, but that of knowledge complex. For, although the principles of knowing are frequently taken from the principles of the thing, they are nevertheless not proximately principles of science except as complex principles flow from them. And in this way Aristotle says above: The suppositions of demonstrations are called principles; and Sophistici Elenchi II, last chapter, he says that one must chiefly insist on the principles of knowing, because, these being known, it is easy to know the things which follow. But of these complex principles nothing more need be said by us, for what is necessary for this doctrine was handed down in Disputations I and III; but the rest pertains to the books of the Posterior Analytics. But the denomination of principle which is attributed to these pertains to some genus of causality or to some relationship from among those which we shall immediately enumerate; for, because knowledge is a certain thing, a principle of knowledge is so called according to some relationship in which it agrees with other principles of things.

4. A principle of the thing, then, can be so called either only by reason of order and any connection whatever, or by reason of an intrinsic relationship. In the former way Aristotle seems to have spoken in the Poetics, a little after the beginning: We say that is a principle which is not necessarily after another, and after which something is apt by nature to be or to come about. But this appellation under this notion is manifold. For, first, in every action or business that from which it is begun is called the principle, which sometimes is arbitrary or casual, sometimes is due to the thing itself, or at least more consonant in order that it come about fittingly, either the nature of the thing which comes about being regarded, or sometimes the knowledge of the operator being considered. And in this way, in the order of science handed down, Aristotle says above that that which is better known to us can be called the principle of doctrine, because thence science is fittingly begun. Secondly, in succession or the order of time the dawn is called the principle of the day, because thence the day begins. Thirdly, in the order of place, he who sits first is called the principle of the others, and that place too from which a fountain arises is wont to be called its principle. Fourthly, Damascene adds that it is also wont to be said on account of the order of dignity, as: The king (he says) is the principle of those over whom he presides; although this can pertain to causality, as Aristotle indicates. Finally, whatever is presupposed to another can be called its principle, as the foundation is called the principle of the house and unity the principle of number. And in every thing which has extension or breadth, the first part or first extreme which is supposed to the others can be called the principle of the whole or of the other parts. Whence this acceptation or denomination of principle is most broad and can be multiplied in various ways, so that it cannot be reduced to a certain and scientific notion, because it is an almost equivocal denomination.

5. What principle more strictly taken signifies.—In another and more philosophical way, then, a principle is so called by reason of some per se relationship between it and that of which it is the principle, so that from it the other in some way per se arises. Which can happen in two ways. First, through positive influx and the communication of its own being; which mode with respect to created things is always with dependence and causality, as we shall explain; wherefore a principle of this kind, speaking philosophically, always puts on the notion of cause. Only in the divine persons is found a principle with true influx and communication of its own being without causality; but why this is so we shall try to explain in the following section. Whence this genus of principle, in so far as it includes the notion of cause, can be divided into as many members as cause. For some principles are intrinsically constituting the thing; but others are extrinsic, which flow being into the thing and remain outside it, as the end and the efficient, of which we must speak afterwards.

6. How privation is called a principle of the natural thing.—Secondly, something can per se arise from another as from a principle not through positive influx, but only on account of a necessary and per se relationship to the other. In which way privation is numbered by Aristotle among the principles of the natural thing, which seems to have a certain intermediate notion between the two modes of principles declared. For the former is most broad and is founded only in any order of priority whatever, nor does it require a per se relationship, but can be found in any genus of composition or succession whatever; but privation in a more perfect and more intrinsic way is called a principle of natural generation. But the other mode of principle through influx is more perfect than that it could belong to privation, because privation, since it is not a true thing, cannot have proper influx into the thing which comes about or into its generation; and much less can it intrinsically compose the thing generated. It is called a principle, then, on account of the intrinsic relationship of generation to it; for, because generation is essentially a transition from non-being to being, therefore it per se supposes privation and comes about per se from it as from a necessary term; by this reason, then, privation is said to be a principle of the natural thing, not indeed of its constitution in completed being, but of generation.

7. Form is the principle of generation in one way, of the thing generated in another.—How matter is the principle of generation.—Indeed (to say this in passing) form too, as it is the principle of generation, is a principle in a far other way than as it is the principle of the thing generated and its constitution; for of the thing itself it is the principle through influx and formal causality, as we shall declare below; but of generation it cannot be the principle in this way, because it cannot be the proper cause of the generation through which it comes about, so as truly to flow into it, unless perhaps it is reduced to the final cause, for the end of generation is the introduction of form; or also to the extrinsic formal cause, in so far as generation takes its species from the form to which it tends; which physical causalities are very improper with respect to such a form, as will be evident afterwards. And therefore this notion of principle by which form is called the principle of generation properly pertains to this last mode; for generation per se and intrinsically intends form as the formal term to which it tends, which is enough for it to be called the principle of generation. But it is otherwise of matter, because this has some influx and causality also with respect to generation, although diverse from that which it has about the constitution of the natural thing; for into this natural thing matter flows by intrinsically constituting it through itself; but into generation not so, but only by sustaining and receiving it. And let these be said on occasion about these principles, because the name of principle of the natural thing is wont by antonomasia to be accommodated to them. Finally, to this last denomination of principle can be reduced some examples posited in the first and general denomination, in so far as in them a per se order, necessary from within, can be found; for so the point can be called per se the principle of the line, and the first degree of the whole quality, and the foundation of the house; although in these such a per se mode of principle is always reduced to some genus of influx or causality.

How to be prior is common to every principle

8. From this enumeration of principles it can be gathered, first, that it is common to every principle that it be in some way prior to what is from the principle; for the very name of principle shows this. Indeed Aristotle, in the cited place of Metaphysics V, gathers that it is common to every principle that it be first, which is something greater than to be prior; for the latter expresses only antecedence to what is from the principle, but the former expresses the negation of a prior. But it is to be considered that that is called a principle simply in some genus or under some notion which is so a principle that it is not from a principle under that notion; for if it is from another principle in that series, it will not be a principle simply in that order, but only in a certain respect with respect to something; for example, a point is then properly the principle of a line when before it no point, and consequently no part of the line, has preceded; but a point continuing the parts of the line can only respectively be called the principle of the subsequent parts, since it is the term of the preceding ones. Which it is permitted to consider more clearly in time; for absolutely that instant alone is the principle of time before which instant no time has preceded, but which time immediately follows; but an intermediate instant will not be called simply the principle of time, but only respectively or under some determinate notion, namely the principle of the day or of the year. And the Saints seem to allude to this propriety of words² when they say that the eternal Father is the principle, fountain and origin of the whole deity. For they do not so speak because the Father is the principle of the divine nature itself, because according to the Catholic faith the divine nature has no principle, because it proceeds from none, otherwise it would be distinguished from it; whence, as this expression is condemned, the essence generates, so also this, the essence is generated or proceeds. They call the Father, then, the principle of the divinity, because in that grade or order (so to speak) of the divine persons he alone is so the principle of the other persons subsisting in the divinity that he has no principle; and therefore he is called the principle of the divinity, that is, of all communication of the divinity. But the Son, because he has a principle, cannot absolutely be called the principle of the divinity; but he is truly called the principle of the Holy Spirit, or of the communication of the divinity after the manner of spiration, because under that notion he has no principle. So, then, it is of the notion of every principle that it be prior to that of which it is the principle; but if it is absolutely and simply a principle in some order, it will also be first in that order.

9. Whether form is prior to generation.—You will say: form is the principle of the generation of the natural thing, and yet it is in no way prior to generation, since it is its formal term. Likewise the theologian will object that in the divine persons no proper priority is found, although in them there is the most proper notion of principle. To the former part the answer is that form is prior to generation in the notion of the per se term to which generation is ordered, which is reduced to priority in the order of intention. There will not be lacking, however, one who says that form is also prior in nature in execution and in the genus of formal cause; but this is not rightly said with respect to generation, because, as I said, it is not its proper cause; it is enough, then, the prior relationship of generation to form for this to be its principle, whatever may be the case with proper causality with respect to it. You will say: then act could be called the principle of potency, because, although it is posterior in generation or time to potency, it is nevertheless the term which potency per se regards and from which it takes its species; whence it is prior in nature in the order of intention. The answer is, first, by conceding the sequel in that genus of specifying principle; for what is inconvenient? Next, there is much greater reason concerning form with respect to generation, because form is so extrinsic to generation that it has it inseparably and intimately and essentially conjoined, so that actual generation cannot be understood without form actually informing intervening there; but act is more extrinsic to potency.

10. The other part of the objection pertains more to the theologians. Among whom there is a certain diversity, perhaps rather in the mode of speaking than in the thing. St. Thomas, then, I, q. 42, a. 3, in the body, although he concedes that among the divine persons there is an order of origin, nevertheless denies that one is simply prior to another, because in the Trinity (he says) there is order of nature without priority. And in the solution ad 2 he declares that there is there neither priority of nature nor of intellect, because those persons are both relative and subsist in the one same nature; whence neither on the side of the nature can they have priority, since that is the same, nor on the side of the relations, since correlatives are simultaneous in nature and intellect. Wherefore the same holy Doctor, in the said q. 33, a. 1, ad 3, so answers the difficulty which we are now treating that he seems to deny our assertion. For he says that, although the name of principle is taken from priority, it nevertheless does not signify priority. For it is frequent that in a name one thing is that which it signifies, another that from which it is imposed to signify. Nor is St. Thomas contrary to himself when, I, q. 40, a. 4, he says that the producing person is, in our mode of understanding, prior to the person produced. For there he speaks of our imperfect and confused mode of understanding. But in the other place he treats of the perfect understanding which is due to things as they are in themselves. And so Cajetan and the Thomists understand, and with them Durandus agrees in the thing, In I, dist. 9, q. 2, and dist. 20, q. 2. And this opinion is sufficiently probable, and that mode of speaking is cautious and secure; according to which opinion our assertion can be limited so that it be understood metaphysically, not theologically, that is, of the principle which the light of nature knows, not that which faith alone reveals. Nevertheless Scotus, In I, dist. 12, q. 2, and dist. 28, last question, whom Gabriel follows, In I, dist. 9, q. 3, concedes that, as in the divine persons one is the principle of another, so it is prior, not in duration, perfection or nature, but in origin only. For this priority does not include imperfection, and is necessarily included in the very notion of the producing principle. Each is evident, because it only imports in the producing person that it has being without such origin, according to which the other person proceeds from it; as the Father has being without generation, but the Son not except through generation; and both have being without spiration, but the Holy Spirit not except through it. Which kind of priority between correlatives cannot be found in created things, because one relative as such does not proceed from another; but in the divine there is found the procession of one correlative from another, in so far as they are such. And according to this opinion our assertion holds universally true; for, if it is found true in the divine persons, much more in created ones. Nor is it wonderful that, as the notion of principle is singular in those persons, so also the mode of priority is peculiar and of a far other notion than all those which are found in creatures. And this mode of speaking too is probable, and in the thing (as I think) St. Thomas does not contradict it, because he never expressly denied this genus of priority in the divine persons, but the others which are found in creatures. He was silent, however, and never used that expression, but called it the order of origin, not priority. And certainly not without cause, both because in divine things the manner of speaking of the Fathers is to be imitated, among whom that expression is not found; and also because the priority of origin is not of absolute priority as it is found in the divine persons, because priority asserted simply and without addition seems to indicate some imperfection in the thing which is called posterior. Likewise because that is called absolutely prior which can either be or at least be exactly understood without the other; but one divine person is compared to another in neither way. But what some add, that one divine person is prior to another in the order of natural enumeration, in which way we number the first, second and third person, this (I say) is not diverse from the preceding, for this mode of enumerating is founded only in the priority of origin; whence in the thing itself it does not indicate another genus of priority; but that mode of enumerating excellently declares that this mode of priority of origin, if it is declared in congruous words and in a sound sense, is not altogether foreign to the manner of speaking of the Church and of the Doctors. Whence with that addition it can be accepted, and is sufficient for it to be universally true that every principle is in some way prior to that of which it is the principle; although this always remains singular in the Trinity, that, while the notion of principle belongs absolutely and simply to one person with respect to another, the notion of prior is attributed only with an addition and limitation; for the former, absolutely said, seems to indicate no imperfection in the other extreme, but the latter some. The priority of origin, then, explained in the said way, is enough for the true notion of principle to be found in the divine; whence what St. Thomas says, that the name of principle was taken from priority, but does not signify it, is true if by priority he understands absolute and positive priority which connotes imperfection in what is from the principle; but if the discussion is of pure antecedence, as it were negative, under that notion under which it is called principle, then not only was the name of principle taken from priority, but it also signifies and requires it with due proportion, as has been declared and is evident from the definition of Aristotle and from all the things adduced.

The description of principle in common is completed

11. The connection required between principle and what is from the principle.—Secondly it is inferred from what has been said that for the notion of principle it is not enough that it be prior to another, but it is necessary that there be between them some connection or consequence of one from the other which is denominated principle. This is evident from the common mode of conceiving of men, and is easily declared by induction. For a man born yesterday is not the principle of one who is born today, although he is prior to him; and in the divine, if the Holy Spirit did not proceed from the Son, the Son could not be called his principle, even if he could in some way be thought prior in reason, namely in the way in which the act of the intellect is said to be prior to the act of the will. Some connection or consequence, therefore, is necessary; and therefore according to the various modes of such consequence the denomination of principle too is various; for sometimes it arises from position, sometimes from intrinsic succession, sometimes from emanation, and so of the others enumerated above. And Aristotle signified all this, in the said place of Metaphysics V, when he said that a principle is the first whence something is, etc.; for that word whence indicates the aforesaid connection or consequence. But this is to be understood with proportion; for a principle can be in act and in potency, and in each way it requires a relationship to the other, which follows upon it either in act or in potency.

12. A certain general division of principle.—What an intrinsic principle is, what an extrinsic.—And so is concluded the description of principle in common and most confusedly taken, which St. Thomas hands down under these terms, I, q. 33, a. 1: A principle is that from which something proceeds in any way whatever; where that word proceeds is not to be taken strictly for true origin, but for any consequence or connection whatever, as we have hitherto spoken; and to signify this St. Thomas perhaps added that particle in any way whatever. And in this sense that definition was taken from the aforesaid place of Aristotle, saying that a principle is that whence something is. For he seems deliberately to have abstained from a peculiar word signifying origin or another mode of emanation, so that by that particle whence he might embrace every mode of conjunction or consequence. But for greater explanation he adds that a principle is that whence something is, or comes to be, or is known, so that together with the description he might explain a certain general division of principles; for to those three members just mentioned all principles can be reduced, especially those which are per se; for those which are per accidens can scarcely be reduced to a certain method, except in so far as they are reduced to those which are per se. So, then, all principles are either principles of the thing in becoming or principles of the thing in being, and to these two members all principles of things are reduced, because another state in things cannot be understood except in becoming or in being; and the principle of effecting is not always the principle of the constitution of the thing, as is evident in privation. But under the principle of that which comes to be is comprehended every principle of motion or operation as such, or of any successive thing whatever, for all these have their being in becoming; but under the principle of that which is are included all the principles of things which in some way have being (as they say) in completed being. But because successive things too and actions themselves in some way are, therefore, taking the word is more generally, it is wont to be said by the theologians that a principle is that whence something is. And in the same way the principle of knowledge could be comprehended under these words, and in truth it is comprehended, if knowledge is considered in so far as it is a certain thing which comes to be or is; deservedly, however, Aristotle adjoined the third member, about the principles of knowledge, to signify that the principle of knowledge is not always the principle of the thing known, but that often the principles of the thing in known being are other than the principles of the same thing in being or becoming. But he did not add in special the principle of loving, because this is nothing but either the principle of being or of knowing. And from these things both the description and the division handed down by Aristotle are sufficiently evident—the division (I say) mentioned, which is three-membered. But after it Aristotle subjoins another two-membered one, saying that one principle is intrinsic, another extrinsic, which is a subdivision of the former members, as he himself sufficiently clearly indicates. And to that three-membered division he reduces all the acceptations of principle which he had enumerated above, and all others which can be thought out. For he was not solicitous in enumerating all the significations of the word itself, which would be prolix and not at all necessary, but those which were either more usual or from which others could easily be known. And therefore I judge it superfluous scrupulously to inquire into the further sufficiency of that enumeration. But if anyone requires a copious disputation on that matter, let him read Fonseca, Metaphysics V, c. 1, through seven questions, especially in the fourth.

The analogy of principle is declared

13. Thirdly it is inferred from what has been said that principle is not said merely equivocally of all the members which are contained under it and were enumerated above, since not only the name but also some notion of the name is common to them. But it is wont to be doubted whether it is univocal or analogous. To which it must briefly be said that it cannot be univocal. For three things can be considered in a principle: one is the thing itself which is denominated principle; another the proper relation according to being which is conceived of the principle to what is from the principle; the third is that which is understood as the proximate reason of founding that relation, which is that consequence or emanation of what is from the principle from the principle. But in none of these do all those things which are called principles agree univocally. The first is evident, because not only uncreated but also created being is denominated principle, and not only real being but also being of reason; but these do not agree univocally in some proper and intrinsic notion; therefore. And the same reason can be made of the second; for the relation of principle too is common to the created and the uncreated, although philosophy does not recognize the latter. Likewise to real relations and those of reason. And from these the same can be concluded of the third: first indeed, because so great is the variety in those notions or connections of what is from principles with the principles, that they scarcely agree among themselves except in name and some proportionality. Secondly, because when that which is denominated principle is only a being of reason, the reason of founding the relation of principle cannot be real; but in other things there is often true emanation and real procession. Again, this is sometimes created, sometimes uncreated; there is, therefore, in these the same reason of analogy. Finally, because principles which are so denominated only on account of the succession of time or the order of position, or another similar accidental connection, are far distant from per se principles, and most of all from those which are such through true influx and causality. Nor does the unity of the description given stand in the way of this analogy; for the terms of which it consists are so transcendental that they involve analogy in themselves. Nor does it stand in the way either that principle is almost always said absolutely and without addition of any of the significates posited above; for this can happen either on account of a clear and known proportionality, or because it is evident from the subject matter in which signification the word is taken, or certainly on account of some proper and intrinsic notion of principle, according to what we shall say below of the analogy of being.

14. The same is analogous with respect to diverse things both by attribution and by proportionality.—The order of the imposition of the word principle to its significates.—But someone will perhaps ask of what kind this analogy is, and of which significates principle is said primarily. On which matter the interpreters say many things, on the said Metaphysics V, c. 1. I, however, briefly judge that this analogy is not one but manifold with respect to diverse significates; for it is not repugnant that the same name, primarily signifying some thing, be transferred to some others by attribution, but to others by proportionality. As healthy, primarily signifying the animal, by attribution signifies medicine, but by proportionality an integral and incorrupt apple. So, then, I judge it must be said of the name of principle with respect to its significates. But it is to be considered that it is one thing to speak of the first imposition of this word as it was made by men, another of the thing signified by it, as St. Thomas distinguishes in a similar case, I, q. 13, a. 6. In the former way I think that this word was imposed to signify the principle of motion or of time; for, because the earlier philosophers knew only corporeal things, they first distinguished in them beginning, middle and end; but these seem to be first known from motion or some action; and therefore it is likely that the name of principle was first imposed to signify the principle of motion or of action, or that part of magnitude from which motion begins. And perhaps Aristotle signified this by enumerating this acceptation in the first place. But hence this word has been derived through proportion or proportionality to other significates.

15. What principle signifies primarily, what secondarily.—But as regards the thing signified, this word more principally signifies per se principles than per accidens ones; and especially those which are principles through true and real influx, because in these there is a much truer and more proper emanation of one from another and origin, which the name of principle shows. But this notion of principle is conjoined with causality with respect to creatures, and belongs both to God and to creatures. And by this reason it can be said of God and creatures according to the analogy of attribution; for example, to be an efficient principle is said analogically of God and creatures, not according to proportionality only, but on account of true and real agreement, analogous however and including attribution, as we shall explain generally below in the analogy of being to God and creatures. And the same can be said of the final or exemplar principle. But how the notion of principle is common to the efficient, final and exemplar principle pertains to the division of cause into these and other members, of which we shall speak below. But in God alone, ad intra (which philosophy did not recognize), is found the true notion of a positive and per se principle with true influx or production without causality, which is a higher and more wonderful notion of principle.

16. Of God, as he is principle of God and of creatures, how principle is said.—Whence the theologians are deservedly wont to inquire whether principle in common, said also of God himself as he is the principle of creatures, or as one divine person is the principle of another, is univocal or analogous. Some think that it is analogous and said first of God according to emanations ad extra rather than ad intra, because the creature proceeds from God not only according to person but also according to nature and essence; and therefore there seems to be a greater notion of principle in God with respect to creatures than there is in the eternal Father with respect to the Son, whose person he produces, not his nature. And it is confirmed, because the notion of principle with respect to creatures is absolute and essential, but the other relative and notional; but those things which are essential seem from their proper concepts to be more powerful and prior to notional ones. It is confirmed, secondly, because potency simply in God is said first of the potency of producing ad extra rather than ad intra; whence God is simply omnipotent through the potency of operating ad extra, not ad intra; otherwise the Holy Spirit would not be omnipotent, because he cannot produce ad intra. But the reason is the same of principle as of potency, since a principle is such by reason of potency. And so Durandus thinks, In I, dist. 29, q. 1.

17. But to others it pleases that it is analogous, said first of the principle ad intra rather than ad extra, both because the relation of principle to creatures is of reason, but among the divine persons it is real; and also because a principle is that whence something is; but the creature is analogically with respect to the divine person proceeding, because the latter proceeds in uncreated being, the former in created; therefore that procession is far nobler, even according to analogy; therefore also the notion of principle which corresponds to it is said first according to emanation ad intra rather than ad extra. And St. Thomas seems to be of this opinion, I, q. 33, a. 1, ad 4, and a. 3. But in those places he does not treat of the name of principle, but of the name of father, of which the reason is far diverse. But under the name of principle he expressly affirms it In I, dist. 29, q. 1, a. 2, where Capreolus, Albert, Richard and others think the same.

18. But a third opinion can be that this name principle is univocal to those two notions; for it is not repugnant that the same name which is analogous with respect to several be univocal with respect to some, as is self-evident and as we shall say more fully below in treating of the community of being and of accident. But that it is so in the present case as regards this part of which we are treating is proved, because here there intervenes neither analogy of proportionality nor of attribution. The former part is proved, both because otherwise God would be called the principle of creatures only through transference, not through propriety; and also because St. Thomas above expressly confesses that there is one common notion of origin of the procession of creatures from God, or of one divine person from another, which is for something to be from something, and so also there is one common notion of principle; but in the analogy of proportionality there is not one common notion. But the second part is proved, because God, as he is called the first principle of creatures, is not referred to himself as he is the principle of the persons; therefore there can be there no analogy of attribution. Likewise because otherwise the Holy Spirit would be called the principle of creatures through attribution to the Father or to the Son, which seems sufficiently absurd. Likewise because here the reason of the analogy of attribution which is wont to be between God and creatures ceases, namely that all the being or all the perfection of the creature is primarily in God and depends on him; but here one notion of principle is not caused by another, nor depends on it; indeed neither does the emanation of creatures per se depend on the emanations of the divine persons; because the multitude of persons was not per se necessary for production ad extra; therefore in the present case every reason of the analogy of attribution ceases.

19. In this matter those three things seem to be distinguished which we distinguished above in every principle, namely the relation of principle, the proximate reason of such relation, and that which is named principle. As regards the first, there is no doubt that here there is analogy, because the relation of principle of God to creatures is of reason, but of the producing divine person to the produced one is real. And Scotus expressly declares this sense, dist. 29, q. 1. Indeed this analogy either is not of attribution but of proportion only, or at least, if it is of attribution, it is not according to a common concept, because here there is none to being of reason and real being.

20. As regards the second, too, I think it more probable that the notion of actual principle is said analogically and more principally of God according to the processions ad intra than ad extra, on account of the reasons adduced. But this analogy is of attribution, and not only of proportion, as is the analogy of being and of the other attributes which are said properly of God and creatures. For this analogy of principle is founded in the analogy which is between creation and the processions of the divine persons in the notion of origin or emanation. Because, if the productions do not agree univocally in the common notion of production, neither can the notion of principle be univocal, especially since to be in this way the actual principle of creatures does not belong to God except through extrinsic denomination from the emanation of the creature from him. But that the notion of procession is analogous with respect to the created and the uncreated, and that it is said first of the uncreated procession, is proved, first, from the general rule of the divine attributes, which are said properly and always first of God, as we shall prove below. But it holds true not only in essential ones, but also in personal ones; for person is said analogically of the created and the uncreated; and Father or Son are said analogically of the divine persons and human ones.

21. Secondly, because also in this notion there is in some way a necessary dependence and natural antecedence between the origins ad extra and ad intra. For, although creation on its own side per se does not require the Trinity of persons and consequently not the processions ad intra, nevertheless on the side of God it per se and necessarily requires them and in its own way depends on them. Both because every effecting per se depends on the acting person; but in God there cannot be a person without production or procession ad intra. And also because the production of creatures of itself depends on intelligence and love; but there cannot be in God intelligence without the Word nor love without the Holy Spirit. And according to this consideration St. Thomas said, I, q. 45, a. 6, that the processions of the persons are the reasons of the production of creatures; and in the answer to the first he adds that the processions of the divine persons are the cause of creation. And so the foundation which we brought in reporting the third opinion against this part remains solved. But the foundation of Durandus stands in no way in the way; indeed it declares that the processions of the divine persons, since they are without any dependence or imperfection, are of so eminent a notion that they cannot agree univocally with created productions. That, therefore, in the person produced the essence is not produced but only communicated does not diminish the truth of the production, but rather pertains to its infinite perfection. As that the eternal Father produces the Son not only similar in specific nature, but also of the same nature in number, does not diminish the truth of generation, but pertains to its infinite perfection, as St. Thomas excellently noted, I, q. 41, a. 5, ad 1.

22. But as regards the third, that is, that which is denominated principle, if it is taken altogether materially (so to speak), it is clear that analogy cannot intervene, nor can there be anything prior to that which is denominated the first principle of creatures. Nor can there be anything more perfect than that which on the side of such a principle is the root and origin of such a denomination; for its perfection is infinite. Indeed even if we speak of that principle not so materially but formally, in so far as it is (so to speak) a principle in potency, then too I think that the notion of principle cannot be said less properly or secondarily of God as he is the principle of creatures; and some arguments made in the first and third opinions persuade this. And most of all because this denomination is absolute, eternal and essential; for it is taken from the attribute of omnipotence; but the potency of God in the notion of active or productive potency is not analogically potency, but primarily and principally. The notion of principle, therefore, as it is precisely taken from it, cannot be analogous.

23. An objection is satisfied.—You will say: then potency is not said analogically of the potency of creating and of generating or spirating; but the consequent seems false, for such is the potency as is the action or production; but production is analogous; therefore also potency. I answer, first, by conceding that there is no such analogy which is said secondarily of the potency of creating; because, as I said, the effective potency of God cannot be analogically potency, because it is so named through no proportion or attribution; and because it is the first and most perfect potency. Whence I add that either as regards this there is univocation, or, if there is some analogy, as perhaps there is, productive potency is said first of the potency of creating, etc., rather than of generating, etc. The reason is that the formal notion of potency, which signifies first act for producing, is found with every propriety and perfection in God with respect to creatures; but with respect to the internal origins, or the divine persons proceeding, it is rather according to our mode of conceiving than according to the thing. Because in the thing it is not so much first act as last with respect to the internal processions, as will be more fully evident below in treating of the knowledge, will and power of God. But the reason is that the potency of God with respect to creatures is to a transient emanation really distinct and not necessarily flowing from such potency; and therefore that is most properly potency and first act with respect to such emanation; but the potency of generating or spirating is according to an immanent procession, which in the thing cannot be only in potency but always in act, nor can it be in the thing distinct from that which is conceived by us after the manner of potency, as regards its absolute perfection, as is evident from St. Thomas, I, q. 41, a. 5; and therefore according to the thing and truth potency is said more properly of the creative than of the generative, etc.

24. Whether the generative and spirative principle are said univocally.—How principle is said of God creating and operating from a subject.—Nor does it stand in the way that origin or production is analogous, both because the potency of God does not take its notion from a relationship to the extrinsic but from its essential and most absolute perfection; and also because it pertains to the excellence of the divine potency absolutely taken that it be neither of necessity conjoined to its action nor be able to have an action adequate to itself or of the same order; and so it comes about that the imperfection which the production or dependence of the creature essentially includes not only does not diminish the perfection and propriety of the potency of God for acting outside himself, but is even a manifest indication of its infinite perfection. But conversely the excellence of the internal origins indicates the supreme and infinite perfection and propriety of the immanent acts of God, and consequently in some way diminishes the propriety of potency in first act, as has been declared. And let these be said in passing for declaring exactly the analogy of principle. But that is more theological which is wont to be asked, whether principle said within God of the generating and the spirating is univocal or analogous; in which I judge with Scotus, in the place cited above, that it is univocal, as is relation or person; nor in those things which are said with every propriety of the divine persons do I understand analogy or attribution, since there there is no dependence, or imperfection, or priority of nature. Again it is wont to be asked whether principle said ad extra of God as creating, or as operating from presupposed matter, is analogous; which some seem to think; but I judge that it is univocal, because effecting is said univocally of creation and eduction, especially that which is done by God as the first agent; but of these these things are enough.

Resolution of the principal question

25. Principle extends more widely than cause.—Finally from what has been said the answer to the proposed question is gathered, on account of which we have said so many things of principle, namely that principle and cause are not altogether the same nor said reciprocally, but that principle is more common than cause. So St. Thomas expressly teaches, I, q. 33, a. 1, ad 1, taking thence the reason why in God one person is called the principle of another and not the cause. He has the same In I, dist. 29, a. 1, in the body and ad 2, and De potentia, q. 10, a. 1, ad 9, and it is the common opinion. Which the reasons for doubting posited at the beginning in the third place rightly prove, and it is manifestly evident from all that has been said of principle. For principle is said also of that which does not properly flow into another, but cause not at all. Likewise hence it comes about that principle belongs not only to real beings, but also to beings of reason or to privation; but cause not likewise. This conclusion, therefore, is manifest comparing cause to principle in its whole generality; but if it is compared to the principle truly and per se flowing some being into that of which it is the principle, the conclusion is also true, yet so difficult that it cannot be known by the light of nature, because in the mystery of the Trinity alone is such a mode of principle found, and therefore it is difficult to assign the difference and reason, of which we shall speak in the following section.

The arguments are solved

26. Whether Aristotle reputed principle and cause the same.—Various places of Aristotle are weighed to this.—To the first testimony of Aristotle posited at the beginning many answer through that dialectical rule, that the truth of examples is not required; for in that place Aristotle posited principle and cause in passing and for the sake of example. But this is a harsh interpretation, or rather a modest concession of an Aristotelian lapse. Others expound that the name cause is not taken there properly, but in the vulgar way as it is said of any occasion or necessary condition whatever. But this exposition too has a difficulty to be touched upon below, for the name of cause, even vulgarly taken, never extends so widely as principle. It can be said, then, that Aristotle says two things there of being and one. The first is that they are the same. The second, that they are convertible among themselves; when, therefore, Aristotle says as principle and cause, he does not compare them in the second, but in the first; for he intends to teach that being and one are the same in the thing, yet not in reason; and to this he brings an example, saying that they are related as principle and cause, not as tunic and garment; whence, immediately after those words principle and cause, he subjoins but not as things which are said with one notion. Or, if in each the comparison is made, it is not necessary to understand it universally of principle and cause, but indefinitely, that sometimes principle and cause, although they follow each other mutually, differ in reason, for example principle and efficient cause.

27. To the second testimony from Metaphysics V some answer that there too the name of cause is taken in the broad and vulgar way. But this is openly against the mind of Aristotle, since he treats distinctly of principle and cause and expounds the significates of each philosophically and properly. Another exposition is that when Aristotle says that cause is said in as many ways as principle, it is not to be understood positively but negatively, that is, that cause is not said in other ways than those in which principle is said, although it is not necessary that it be said in all those ways. And indeed, although the propriety of that word in as many ways seems to resist this exposition, nevertheless the reason which Aristotle subjoins seems to compel its admission; for he subjoins: Since all causes are principles. From which reason it would most ineptly be inferred that cause is said in all the ways in which principle is said; for it would be to argue from the superior to the inferior affirmatively; as if someone gathered: Every substance is being; therefore in as many ways as being is said, so many is substance said.

28. But Alexander of Hales indicates another exposition, namely that principle is said in as many ways as cause is said, because every cause is a principle. So that, after the significations of principle were enumerated, Aristotle subjoined as it were a general rule, that principle is also said in all the ways in which cause is said, although not in those alone. And according to this sense Aristotle’s reason fits excellently; yet it can scarcely be accommodated to the former words. Another exposition is indicated by St. Thomas, namely that so many acceptations of principle as are enumerated there belong to cause, although not under the same notion; for from a cause motion begins, and so of the others. According to which exposition Aristotle’s proof is to be brought in otherwise, namely so that thence he confirms that those acceptations have place in principle, because they also have place in cause, because every cause is a principle; but it does not follow thence that cause and principle are said reciprocally, because, although the acceptations enumerated there can according to other notions be accommodated to cause, nevertheless principle extends more widely, because it is said in all those ways in which cause is said and according to the proper notion of cause; and moreover it is said in other ways according to the general notion of principle.

29. To the third testimony from Metaphysics XII, where Aristotle calls privation a cause, the common and necessary exposition of all is that he used there the name of cause in the vulgar way, as whatever is in any way required for another is called a cause.

30. But someone will say: then, if we speak truly and with proportion, it must be confessed that principle and cause are said reciprocally; for if each is taken in its whole amplitude and analogy and vulgar use, they are convertible; but if cause is taken strictly and with every propriety, it is also convertible with principle taken in the same way. But if cause is taken properly and principle broadly, and principle is therefore said to be more general than cause, an improper comparison is made; and by the same reason it could be said that cause extends more widely than principle, because, if cause is taken broadly and principle properly, it will extend more widely. I answer by denying each part of the assumption; for, comparing the proper and per se principle to the proper and per se cause, the principle is more common, as is evident theologically in the principles of the divine processions and physically in privation. And taking each in its broadest signification, I also think that principle is something more common. For, although cause so taken comprehends many things which are not properly, truly and per se causes, nevertheless it comprehends nothing which is not contained under the general signification of principle; but principle embraces some things which are in no way called causes, even in vulgar speech; for the first-born is called the principle of the sons, yet not in any way the cause.

31. The Greek Fathers used the name of cause for principle.—To the manner of speaking of the Greek Fathers the answer is that they used the name of cause more broadly than it can or ought to be used in Latin propriety; yet in the thing itself they did not attribute the name of cause to the divine persons ad intra in so far as it properly expresses a relation to an effect and in that indicates some imperfection; but only as it expresses the origin of one from others.

32. Whether there is something from a principle in the divine, and what the correlative of principle is.—To the reason, the theologians deny that principiatum [what is from a principle] is the correlative of principle in the divine. Although, then, they say that the Father is the principle of the Son, they nevertheless deny that the Son is principiatum by the Father. So St. Thomas, I, q. 33, a. 1, ad 2, and others commonly. According to which mode of speaking the correlative of principle will be that which is from another. Which opinion has deservedly been approved by the Latin theologians out of reverence for the mystery of the Trinity and to take away the occasion of error; for principiatum seems to signify something made, as we argued above, or also indicates the same as initiated, and consequently indicates a beginning of being. But, that mystery being omitted and the odium of the word taken away, if by the name of principiatum there is signified only that which is the correlative of principle, then it is denied that principiatum is the same as caused or effect; but it signifies only that which is from another or which has a principle, not of duration (for this equivocation too is to be taken away), but either of origin or of any other mode. And in this sense are to be explained the Greeks, who, as St. Thomas reports above, admit that the Son is principiated by the Father.

33. The things which prove cause wider than principle are solved.—To the arguments made in the second place, by which it is proved that cause extends more widely than principle, the answer is that Aristotle in the first testimony does not speak generally of principle, but of the first principle in some order, which has influence and causality. Of which principle he had said in the same place that, although it is small in magnitude, it is great in power. And of this first principle he denies that it has a superior cause, namely in that order. For only the first principle absolutely and in the whole breadth of being has no cause. And in the same sense in Physics I he posits in the definition of the principles of natural being that they are not from others, namely in the way in which natural being is from them, because those are the first principles in that order. Of which principles as they are principles and their proper definition one must dispute in Philosophy; but as some of them are causes, it will be said of them below.

1. From Aristotle we have no definition of cause in common; later philosophers laboured in assigning it, so that one might proceed better from the common to explaining the proper notions of the individual causes, and at the same time it might be declared what the agreement of causes among themselves is. But it is to be supposed that the discussion is of cause in act, formally as it is cause; for, as we were saying above of principle, so also in cause three things can be considered, namely the thing which causes, the causation itself (so to speak), and the relation which either follows or is thought. Of this third member nothing is to be treated in this whole matter; for it has its proper place below in the matter on relation. But of the other two we are going to speak; first, however, of causation itself, through which cause in act is formally constituted and from which the cause itself, or the power of causing, becomes known to us.

2. The first description of cause is rejected.—The first definition, then, is wont to be handed down thus: A cause is that through which the question is satisfied by which it is asked on account of what something is or comes about. Which can be taken from Aristotle, Physics II, c. 7, where he proves the sufficiency of the causes from this, that through them all the ways in which it is wont to be asked on account of what a thing is are satisfied; he signifies, therefore, that a cause is that through which the question on account of what is satisfied. Whence it is evident that the expression on account of what is not taken in that special way in which it is wont to be said of the final cause, but more generally so as to comprehend all. But this definition declares almost nothing of the thing; for it is equally obscure what that word on account of what signifies; for, if it is rightly taken, it signifies only the relationship of the final cause, and does not sufficiently declare even that, as we shall see afterwards. But if it is taken more widely, it comprehends the various modes which are signified by those words, from which, through which, by which something is; whence only a common name is imposed, yet the common notion is not explained. I add that that word in that generality can also comprehend principles which are not causes, as Christ said, John 6: I live on account of the Father, where not the relationship of cause but only of principle is signified.

3. The second definition of cause is refuted.—The second definition, and a very common one, is: A cause is that upon which another follows, which is wont to be reported from the book De causis, where it is not found; and it seems rather to have been taken from the definition of principle declared above from Aristotle, Metaphysics V. For what Aristotle posited, first, in place of a genus is posited in that definition of cause through a more transcendental term, namely that; but the remaining particles, namely upon which another, manifestly are equivalent to those words of Aristotle, whence something. Finally what Aristotle said under a disjunction, is, or comes to be, or is known, is comprehended sufficiently confusedly under the single word follows; for in this word consequence through inference alone cannot be signified, otherwise the definition would belong also to effects from which causes are inferred; it is necessary, therefore, that it signify generally any connection or consequence whatever. And from this very exposition the chief argument is taken against the definition itself; because that definition is not so much of cause as of principle; whence it also belongs to privation, for upon it change follows; unless perhaps it be said that the word follows is to be understood through influx and dependence; in which sense the definition will indeed stand, yet it will be very obscure.

Resolution of the question

4. The genuine and adequate description of cause.—The third definition is that which some moderns chiefly bring forward: A cause is that on which something per se depends. Which indeed, as regards the thing, meets with my approval; yet I would more willingly describe it thus: A cause is a principle per se flowing being into another; for in place of the genus I think it more fitting to posit that common name which belongs more nearly and more immediately to the thing defined; but principle is compared in this way to cause; for being and that relative that, which, posited absolutely, is equivalent to it, are most remote. But through that particle, per se flowing, privation is excluded, and every per accidens cause, which per se do not confer or flow being into another. But that word flows is to be taken not strictly, as it is wont to be attributed specially to the efficient cause, but more generally, as it is equivalent to the word of giving or communicating being to another. But some object against this part that the material cause does not give being, but the formal; and among extrinsic ones the final does not give being, but the efficient. But, although in a special way it is attributed to those two causes to give being—to the form as completing the proper and specific being, but to the efficient as really flowing—nevertheless absolutely and under the common notion matter too gives being in its genus, because the being of the effect depends on it, and it itself gives its entity by which the being of the effect is constituted; the final cause too, in the way in which it moves, flows also into being, as will be declared afterwards.

5. But for declaring further this part of the definition it is to be noticed that, if we treated philosophically only of natural causes and principles, or those which can be known by natural light, cause would seem sufficiently defined by those words and distinguished from all principles which are not true causes; but because our physics and metaphysics must serve theology, it is necessary to hand down such a definition of cause as does not belong to the eternal Father as he is the principle of the Son, or to the Father and the Son as they are one principle of the Holy Spirit; and this is what creates difficulty for us; for the producing person seems to be a principle per se flowing being into another person, and so the whole definition of cause seems to belong to it, although it is not a cause, as is evident from the received opinion of the theologians.

The difficulty taken from the mystery of the Trinity

6. In order, then, to exclude a principle of this kind giving being per se without causality, modern authors have used the word depending, because one divine person so receives being from another that it does not depend on it, because that which depends on another must have an essence at least diverse in number from that on which it depends. But first of all it is necessary to explain what it is properly for one thing to depend on another, or why for depending a diversity of essence is required and the distinction of things which necessarily intervenes between the producing and the produced thing does not suffice; because no reason appears why the word depending requires a greater distinction than producing.¹ Likewise one relative is properly said to depend on another, because, it being posited, it is posited, and, it being taken away, it is taken away; and yet it is not of the necessity of relatives as such to have an essence distinct in number; for the divine persons are correlative, although they are of the same essence. But if they are said to be of the same absolute essence, yet distinguished in respective notions, and this to be enough for correlative dependence, why will the same not suffice for the dependence of the produced on the producing? For it is not produced in so far as it is the same as the producing, but in so far as it is distinguished from it; but as such it has a distinct respective entity received from another; therefore according to it it truly depends on another. Add that according to its proper respective notion the produced person has a personal and respective being distinct from the producing person; and it cannot have that unless given by another; therefore in that it truly depends on another. For what is it to depend on another in some being, except not to have it from oneself, but given and communicated by another, by whom it must always be given in order that it can always be had?

7. What it is properly to depend on another.—Why the produced divine persons do not depend on the producing one.—In order to explain this, then, I said that a cause is that which flows being into another; for by these words the same thing is declared which is imported in the word depending; but it is signified by them that for causality it is necessary that that being which the cause per se primarily flows into the effect be caused by the cause itself, and consequently that it be a being distinct from the proper being which the cause has in itself. Whence this is properly to depend in its being on another, namely to have being distinct from it and participated, or in some way flowing from its being. But that this mode of dependence is found in all the causes which we experience can briefly be shown in every genus of causes. For matter and form flow being into the composite, communicating indeed themselves and their entities; but the being of the composite which thence arises is distinct from the being both of matter and of form, and therefore properly depends on them, because to constitute it each confers its being, and thence arises a being distinct from either of them, which cannot be without them. This is evident in the efficient cause (the final being omitted for now, which has a more obscure influx, of which we shall see below); for every thing which flows being into another after the manner of a per se and extrinsic principle, outside the mystery of the Trinity, gives it by effecting the very being which it communicates; and therefore it always gives a being distinct from the proper being which it has in itself; and this is properly to cause and to effect. And conversely the produced thing then properly depends in that genus of efficient cause when the very being which it has from another, per se primarily received, flows from the being of another and cannot be without such influx. But in the processions of the divine persons it does not so happen, because that being which per se primarily is communicated through those productions is not other than the very being of the producing person, but is itself the same in number which is in the producing person; and this is singular and wonderful in those divine processions; and therefore one person so proceeds from another that it nevertheless receives from it a being altogether independent, because it receives the very being in number which is in the producing person.

8. An objection is met.—Nor does it stand in the way that the relations themselves are distinct and have a proper distinct relative being, because not relative being as such, but absolute and essential being, is per se primarily communicated through those processions. For God proceeds from God, and the Father, by generating the Son, primarily communicates to him his nature; but the relation is required as a necessary property for constituting a distinct person; which is as it were material (so to speak) in every production. As in human generation what is per se primarily and formally intended is the communication of human nature and human being; but consequently personality is required. The notion of production, then, is principally to be weighed from the formal being per se primarily communicated. Whence the generation of Christ as man was truly human on account of the true being of human nature, even if the personality was of another notion. So, then, because the divine generation is such that the being which per se primarily is communicated through it is not flowing from another being, and therefore neither depending nor caused, but only communicated by the producing person, therefore that generation is not effecting nor causation (so to speak), but a production of a far superior notion. To this is added that the very relative being of those persons is such that it essentially includes the whole divine being, which is essentially independent; and therefore neither can the relative being itself be called dependent.

9. One relative, even created, does not properly depend on another.—But in created relations one relation is sometimes said to depend on another, in so far as it cannot be without it. But this is an improper and broad expression, because where there is dependence as we are now properly speaking there is priority of nature; but mutual relations are altogether similar, and it will be said less improperly that a created relation depends on its term, if it is supposed to be something absolute, because, foundation and term being posited, the relation results. From which it comes about that in created things much less can one relation be said to flow into another, since one is not the cause, indeed not even the principle, of the other, but they only have necessary simultaneity or concomitance. But in the divine, although one relative proceeds from another, it is nevertheless not through dependence nor through the influx of a diverse essential being which per se primarily is communicated through such production.

10. In order to declare this property of cause, then, we said that it is a principle which flows being, because it is necessary that the very being be caused and consequently essentially distinct from the being of the cause itself. To indicate which too, I deliberately added the particle into another [in aliud] and not into someone or into another person, for another thing [aliud] absolutely and properly is not said except of that which is diverse in essence. But that cause includes this property and requires such a mode of influx cannot be proved otherwise than from the common notion and use of this word, especially among the Latins. Likewise from the correlative, which is commonly thought to be the effect, which word openly indicates imperfection and dependence in that rigour which we have declared; wherefore it is certain that the produced divine person cannot be called an effect, otherwise it would also be called made, which is against faith, as is evident from the Creed. Finally, because from the thing itself, as it has been declared, it is evident that that mode of influx or emanation which belongs to created effects with respect to all their causes is of a far diverse notion from the emanation of one divine person from another, and has that mode of dependence which we have declared; it can, therefore, be signified by one common word which comprehends the causes of created things and not the principles of the divine persons; but of this kind is this word cause and the concept which corresponds to it, which we explain through the said definition of cause. So, then, it is true that it is of the notion of cause that it be essentially diverse from its effect, and that the effect properly depend on the cause; but each is indicated in that particle, as it has been declared by us, and through it the principle in the divine is excluded from the notion of cause.

The difficulty from the mystery of the Incarnation

11. But another difficulty arises for us from another mystery of faith, namely the Incarnation; for to the divine Word as personally terminating the humanity the whole definition of cause belongs; and yet as such it is not a cause according to sound doctrine, since it can be neither a formal cause, because that is imperfect, nor efficient, because otherwise the Word would have an efficiency ad extra not common to the Father and the Holy Spirit. The major proposition is proved, because according to the common manner of speaking of the theologians the divine Word terminates the dependence of the humanity; therefore the Word is that on which that humanity depends. But if you say that it depends indeed on it as on a term, not as on a cause, first the difficulty is not solved; indeed rather thence it is concluded that not everything on which another depends is a cause; and next it is very obscure what it is to depend as on a term. But this latter is not wonderful, because the matter is very supernatural, which the theologians explain as they can.² But that former point plainly convinces that the definition of cause is better explained through principle per se flowing being into another than through dependence, unless this particle is declared through the former. Therefore the Word, as terminating the humanity, is not a principle per se flowing being into it, nor does the humanity in this way depend on the Word as on a principle flowing being into it, but only in the notion of term, which is a certain necessary property, without which that humanity cannot exist.

12. How the divine Word concurs with the humanity to the constitution of Christ.—What causality terminating modes exercise with respect to the things terminated.—Which answer rightly satisfies as regards the dependence of the humanity on the Word;³ yet there still remains a difficulty about the dependence of Christ as he is a composite person. For I suppose from the true doctrine of the theologians, indeed also of the Councils and the Fathers, that from the Word as terminating the humanity and from the humanity itself there arises the person of Christ as God-man, one per se and wonderfully composite. That composite, therefore, truly depends on the Word as on a certain intrinsic principle of which it consists; whence it is necessary that it flow being into it, by communicating to it its personal being; from which together with the humanity this composite person results, which as such is in some way distinguished from the Word barely taken. But to this the same answer is to be applied, for the Word does not concur otherwise to constituting that composite than by terminating the humanity; whence, if in this it does not exercise some genus of causality, neither in constituting that composite person does it have some notion of cause with respect to it. But the argument made proceeds not only in the said mystery, but can be accommodated to all the extremes composing some composite, as is the point with respect to the line, and created subsistence with respect to the supposit, etc. Of all which it must be said that it rightly proves that they are indeed reduced to some genus of intrinsic cause, that is, formal or material; but how and in what they sometimes fall short of the propriety of such causes, and especially in the said mystery, depends on what is to be said of these causes in particular.

What causality is

13. From the things which we have said of the notion of cause in common it is gathered, first, what that is by which cause in act is formally and proximately constituted in the being of cause, which is wont to be called causation or causality in common; but this is nothing other than that influx or concurrence by which each cause in its genus actually flows being into the effect; but this concurrence must necessarily be something distinct in the thing, or from the nature of the thing, from the relation of the cause itself, since the thing which is denominated cause can remain in the thing without this actual influx; which is a certain sign of distinction from the nature of the thing, as was seen above. But this influx cannot be only the predicamental relation of the cause to the effect; for this, whatever it is, results from the influx itself of the cause as terminated at the effect, namely in the way in which it is wont to be said that, foundation and term being posited, the relation arises; that influx, therefore, is something prior to the relation; and according to it too the cause is prior in nature to its effect, although according to the relation they are simultaneous in nature. That influx, therefore, is something intermediate between the entity and the relation of the cause; but what it is, and whether it is something in the cause itself or in the effect, and whether it is some mode distinct from them or only a denomination taken from both, cannot be explained here more distinctly until we come to declaring the individual genera of causes. And the same holds of certain properties or conditions which seem to accompany the common notion of cause and are found diversely in diverse causes, as to be prior in nature, to be distinguished really or essentially from the effect, etc.

The single objective concept of cause

14. Secondly it can be gathered from what has been said that the name of cause is not merely equivocal, since not only the name but also some notion of the name is common. But whether to this name, according to that definition, there corresponds one concept, both formal and objective, of cause in common is in controversy; for some think that such one concept does not correspond, because the modes by which effects depend on causes in the diverse genera of causes are so primarily diverse that one common notion of dependence cannot be abstracted from them. But this is neither proved by them, nor does it seem to me very likely; for from every real agreement a common concept can be abstracted; but among causes there is not only some metaphorical proportionality, otherwise cause would not be said of all of them with propriety, but there is true and real agreement, as can also be confirmed from the definition given and its exposition; and from what we have said of the concept of being, many things can be applied here. There is no reason, then, why one common concept of cause should be denied. But whether according to it there is univocation or some analogy will be better evident after the division of cause has been handed down and the individual members and modes of causing explained; and therefore we shall omit that until we compare the causes themselves among themselves.

1. Celebrated is that division of cause into four genera of causes, namely material, formal, efficient and final, which Aristotle hands down, Metaphysics V, c. 2, and Physics II, c. 3 and following; the exposition of which division depends altogether on the exact understanding of the individual members, which we shall pursue at length in this whole treatise; and therefore we shall now propose in common only those things which can be doubted about this division, and dispatch them briefly. The first is whether all those members are truly and properly contained under the thing divided. The second, whether they are distinguished and opposed among themselves. The third, whether they sufficiently comprehend the whole thing divided. The fourth, whether cause is proximately and immediately divided into those members, or some intermediate division can be thought out. The fifth, whether that division is lowest or atomic, or whether the individual members can be divided into others. The sixth, whether it is univocal or analogous.

The four proper genera of causes

2. The assertion is proved from experience.—To the first doubt it must be said that all those truly and properly participate the notion of cause; and therefore cause is deservedly divided into those four members. This assertion, besides the common consent of all after Aristotle, is proved thus. For that those four are found in things or in the effects which we experience can easily be declared by supposing that something new comes about in the nature of things; which is so evident from the perpetual vicissitude, alteration, generation and corruption of things that it would be superfluous to prove it by arguments. If, then, something comes about anew, some other thing is necessary by which it comes about, because the same thing cannot make itself; and this we call the efficient cause. Which either produces its effect from nothing, or from some thing which it presupposes for its action; the first cannot be said universally, for it is evident by experience that neither does the artificer make a statue except from wood or bronze, nor does fire heat unless something is supposed to it which receives heat, nor effect fire except from wood, tow or another similar thing. Indeed this mode of acting is so proper to natural causes that the philosophers who attended only to them took thence that axiom: From nothing nothing comes. That subject, then, which is supposed for the action of the efficient cause, we call the material cause. But it is necessary that the efficient cause introduce some thing into such a subject; otherwise it would effect nothing new, against the hypothesis posited. That, then, we call form, whatever it may be, of which we shall see afterwards. Finally, since causes acting per se do not act rashly and by chance, as is evident from the very experience of things, and especially in human actions, so that the matter is beyond controversy, it is necessary that besides those three there be also an end for the sake of which the efficient cause operates. These four members, then, are found in things, whether all of them are found in individual effects or not; for this will be to be inquired afterwards; for at present it is enough that these are found in the universe of things.

3. Matter is truly a cause. Form is properly a cause. The efficient is truly a cause. Whether the end is a true cause.—But that each of these is a true cause can easily be proved of the material, formal and efficient; for each of these manifestly flows some being; for matter is defined by Aristotle as that from which, being present in it, something comes about. Where by the particle from taken with propriety matter is distinguished from the other causes; but by the particle being present in it is separated from privation, and the proper influx is declared by which matter, and universally the subject, offers itself, so that from it the being of the whole may arise. Similarly the form offers itself so that by it as by act the composite may be constituted; indeed form is frequently wont to be defined as the intrinsic cause which gives being to the thing; for matter is as it were a certain inchoation or foundation of being itself; but form consummates and completes it; on account of which it is called by Aristotle in the places cited the notion of the quiddity. Likewise these are numbered among the intrinsic principles of the natural thing, or rather those two alone are the principles constituting the natural thing; but they are per se principles, since they are most of all necessary and essential, and they give being in the way which has been explained; they are, therefore, proper causes. Of the efficient too it is evident, because by its action it effects that the thing has being which it did not have before; and to this its action per se and directly tends; therefore the efficient is as it were the fountain and principle per se flowing being into the effect; which being of the effect is distinct from the being of the efficient; therefore the whole definition of cause belongs most properly to the efficient. But of the end there can be some reason for doubting, because no real being is presupposed in it by which it could cause; but because of this one must speak more fully in the proper disputation, now it is briefly declared, because, although the end is last in execution, it is nevertheless first in intention, and under that notion it has the true notion of principle; for it is the first which excites or moves the agent to act; but it is a principle not feigned but true and real, because it truly excites and moves. Whence, as it has sufficient being by which it can exercise such a notion of principle, so also the notion of cause; but that being, although it is in the mind, is not outside the breadth of real being, and therefore can be sufficient for such a notion of cause. Again, a principle of this kind is not per accidens but per se; indeed from it the causality of the agent has it that it tends per se and orderly into the effect; and by this reason it per se flows being into it; therefore the definition of cause belongs truly and properly also to the end.

4. The first objection.—The Stoics recognized only the efficient as a true cause.—The second objection.—But against this opinion someone can object Augustine, Eighty-three Questions, q. 28, saying: Every cause is efficient. Which opinion he seems to have taken from Plato, in the dialogue on the Beautiful, or which is entitled Hippias Major, where he signifies that cause and efficient are the same and that the end cannot be called a cause; which he confirms both because it is an effect, and because there cannot be a cause of the efficient cause itself. That this was the common opinion of the Stoics, namely that the efficient cause alone is a true cause, Seneca reports, Book VIII, Epistle 66, where he himself also approves it: Since if all things (he says) without which the effect cannot come about are to be placed in the number of causes, more would have to be numbered, namely time, place, motion, etc., without which no effect comes about; one must, therefore, stop at the one efficient cause, but the others are as it were aids of this cause, or necessary conditions. Otherwise it could be objected at the other extreme from Socrates in Plato, in the Phaedo, that the end alone deserves the name of cause, for the whole cause of the thing is that for the sake of which it comes about; but all the others are only conditions required in order that the thing come about; whence to the question on account of what the thing is or comes about only the answer through the final cause satisfies.

5. The first objection is unravelled together with a difficult place of Augustine.—To the former objection, the place of Augustine is difficult; for he denies there that it is to be asked why God willed to create the world, because this is to ask the cause of the will of God; but every cause is efficient, which cannot have place in the divine will; where Augustine seems plainly to confound the final cause with the efficient; for he who asks why God willed to create the world does not ask the efficient cause, but the final. But it must be said that the sense of Augustine is that a cause is not to be sought why he willed to create the world, so that some proper cause of the will of God itself is thought to be, because, if the divine will had some cause of this kind, it would have an efficient cause; not because end and efficient are formally the same, but because nothing can have a proper extrinsic final cause without having an efficient, either because the end itself does not cause without efficiency, as many hold; or because the end proximately moves the efficient to effecting. When, therefore, Augustine says that every cause is efficient, he is speaking of extrinsic causality, which is never without the intervention of the efficient cause; yet Augustine does not intend to exclude that another genus of causing can be conjoined with that cause. Others answer more briefly that Augustine spoke strictly of cause as it expresses a relation to an effect also strictly taken and denominated from the verb to effect. But this can scarcely be accommodated to Augustine’s discourse, for he who asks why God willed, etc., does not ask a cause so strictly taken.

6. Plato admitted as many genera of causes as Aristotle.—The sense of the ancient philosophers on this.—Why the efficient usurps the name of cause by antonomasia.—To Plato, it is certain that he posited all the genera of causes which Aristotle posited, and perhaps more, as we shall see afterwards. And in the cited place he does not say that cause and efficient are the same, as is attributed to him, but conversely he says: The efficient is nothing other than cause. Which proposition cannot be simply converted, as is self-evident. But thence he does not infer that the end is not a cause, but infers that that which is made by the efficient cause is distinct from it, because a cause cannot effect itself. But of the other philosophers I think that they dissent from Aristotle in words rather than in the thing. For they do not deny the necessity and the concausality of matter, or form, or end; but they differ in names: rarely do they call matter something prerequired; but form they judge should rather be called an effect than a cause, because the whole causality is terminated at it, or at most they call it part of the cause, as Seneca speaks above; but the end they call in some way a cause, or rather a concause with the efficient, or something supervening on the efficient, by means of the purpose or intention of the end, so that it can cause. Moreover the efficient cause has an influence both more real and in a certain way more immediate to the effect than the end; and better known and in a certain way more proper than matter and form, and also prior to them; and therefore the name of cause is sometimes wont to be taken by antonomasia, or also by reason of first imposition, for the efficient cause. Nevertheless, considering the thing itself physically, there is no doubt that each of the said causes has the true and proper notion of cause, and in its genus total and plainly diverse, as we shall say in the second point; and therefore Aristotle much better numbered these distinctly under the common notion of cause.

7. Why place, time and the like are not causes.—Nor does the reason adduced from Seneca stand in the way at all; for not all things without which the effect does not come about are numbered among causes, but only those which per se flow into the effect. Which place does not have, because it is something extrinsic; or, if the discussion is of intrinsic where, that is not presupposed but follows in the effect as a certain accident of it. And the same holds of time; for as it is a common measure, it is extrinsic; but as it can be intrinsic, it is only the duration of the very motion by which the thing comes about, when it comes about successively; but that motion is not a cause, but is rather the actual influx itself of the efficient cause successively, as will be declared below. But matter, although it is something prerequired for the action of the agent, nevertheless in the very instant or time in which the agent acts, matter too per se flows into the effect, indeed even into the very action of the agent, if it operates from it, as we shall see afterwards. But form, although it is the effect of the agent or also of the matter, is nevertheless the cause of the whole composite, completing its essence. And although it is part of the composite, it is nevertheless in its genus its total cause, nor is there reason why it should be called part of the cause, because it is neither part of the agent nor of the matter. But if it is called part of the cause with respect to the whole causality necessary in every genus for the effect, in this way matter and efficient too can be called part of the cause; yet it is an improper expression, because all those do not compose one cause, but an aggregate or required number of causes. And the same holds proportionally of the end; for, although it is required on the side of the agent in order that its action come about not rashly but by design, it nevertheless has a proper and per se influx diverse from the influx of the agent; but of what kind that is, and whether it is always necessary, we shall say below.

8. In moral things the end is the more excellent cause.—Whence to the other part of the objection the answer is that Plato and Socrates in that place speak morally rather than physically. For in moral things the end is in a certain way the whole cause of actions or effects, not that the other causes are excluded in so far as they are physically necessary, but that all the others take from the end as it were the first reason of causing. Whence the end can in a certain way be called the only cause, because it is so a cause that it has no prior cause or reason; but all the others are so causes that they have some prior cause or at least prior reason of causing; which I say on account of the first efficient cause, which is God, as we shall declare below. But if force is put on the word on account of what, it must be said that strictly taken it is accommodated only to the end, but more broadly it is also wont to be extended to all causes. Indeed Aristotle above thence proves the aforesaid genera of causes, because through all of them the question on account of what is wont to be satisfied; for we say that man is mortal on account of matter, and lives on account of the soul, etc.

The mutual distinction of the four causes

9. From these it is easy to dispatch the second point, about the distinction of these causes. But the discussion can be of distinction formally and precisely in the notion of cause, or of distinction as it were material or real in the being of being. The former distinction is that which pertains to the present point, which it is certain is found between these members. First, from the testimony of Aristotle, because otherwise the division would be vicious. Secondly by reason, because cause, as cause in act, is formally constituted through actual influx into the effect; but in those four members there are influxes of diverse notions; therefore. The minor is proved, because the influx of the material and formal cause is intrinsic through internal composition, but the influx of the efficient and final cause is extrinsic. Again, the influx of matter is after the manner of potency, but of form after the manner of act. Likewise the influx of the efficient is through real action or change; but the influx of the end is through intentional or metaphorical change; therefore all these causalities are formally distinct; they constitute, therefore, causes in act formally distinct. Whence also the notions or powers of causing of these causes are distinct; for matter causes in so far as it is passive potency; but the efficient in so far as it has active potency over another; but the form in so far as it has the power of actuating through itself; but the end in so far as it is good and through goodness has the power of alluring the effect; all of which will be expounded more fully in what follows; nor does a special difficulty occur here about this part.

10. The same thing can exercise the functions of diverse causes with respect to diverse effects.—But about the real or material distinction of these causes it can be doubted whether it always intervenes, or whether it can happen that altogether the same thing has several of the enumerated notions of causing. But this can be asked either in order to diverse effects or to the same. In the former way it must be said that a real or material distinction is not necessary between the said causes, because it is not repugnant that altogether the same thing in order to diverse effects have several causalities of diverse notions. For the same form is the end with respect to the generation or alteration through which it comes about, and is form with respect to matter and the composite, and is the efficient principle with respect to action on another, and can be the material cause of its properties, as is the rational soul in so far as it is the subject of the intellect or will. For these influxes or causalities, however diverse in notion they are with respect to diverse effects, do not have repugnance among themselves, nor is it repugnant that they proceed from the same thing; because, just as the same thing is capable of diverse respects in order to diverse things—for it is similar to one and dissimilar to another, the principle of one and the end of another—so it can in order to diverse effects participate diverse respects of causing. The a priori reason, finally, is that the same created thing can in its entity include act mixed with potency, and therefore can be compared to one thing after the manner of formal act, but to another after the manner of a subject; but formal act, since it gives being to the thing, is at the same time wont to be the principle of acting on another, because operation follows being; and finally, because such act is some good, it can also be the principle of metaphorical motion. So, then, it is not repugnant that all these genera of causes meet in the same thing with respect to diverse things.

11. But if sometimes they are not conjoined in some thing, it is not from the formal repugnance of such causalities in order to diverse things, but from a peculiar condition. And sometimes it comes from perfection, but sometimes from imperfection; for example, God can be the efficient and final cause, yet not the material with respect to anything, because he is pure act and has no passive potency; nor can he exercise formal causality either, because this requires an incomplete and imperfect entity. And for the same reason angelic substances cannot exercise formal causality; but because they are not pure acts, they can in some part exercise material causality, at least with respect to some accidents; and because they are not pure potency, they can have some notion of effecting, and much more of finalizing. But conversely prime matter, although it can exercise material causality, nevertheless, because it is pure potency, participates neither formal nor properly effective causality; yet, because it is not so pure potency that it does not have some entity and actuality, it can have some final causality, by reason of which the soul desires its body and any form whatever matter. But the substantial form, although it can exercise formal, efficient and final causality, yet not substantial material causality (so to speak), because it is not passive potency in the genus of substance. But with respect to accidents it can sometimes exercise this causality, which belongs properly to a subsisting form, for that form which on account of its imperfection cannot subsist of itself is not able of itself to sustain accidents either. And in this way one can easily run through the accidental entities, in so far as they can participate the aforesaid notions of causing.

12. With respect to the same thing the same thing cannot undergo the functions of form and matter.—Form and efficient with respect to the same thing cannot coincide in the same.—But if these causes are compared to one and the same effect, there is a somewhat greater difficulty. And indeed in some there is clear repugnance, but in others conversely there is manifest possibility, but in some the matter is controverted and doubtful. Thus that the same thing in order to the same be at the same time material and formal cause is plainly repugnant, because these causalities require formally opposite conditions, such as are to be in potency and in formal act; whence, if the discussion is of a proper substantial form, it always requires a real distinction from its material cause, and the same holds in an accidental form which has its proper entity. But because there are some accidental ones which are only modes of substance, as local presence, or if there is anything else of this kind, in these, as the notion of form is imperfect, so a modal distinction suffices. It is always necessary, however, that the formal and material cause with respect to the same composite be distinguished really or from the nature of the thing. Next it is also evident that the formal and efficient cause cannot be conjoined in the same thing with respect to the same effect; because form exercises formal causality in that in which it is, but efficient with respect to another form or composite; and therefore form as informing either is supposed to the action as a principle of acting, or follows as the effect or formal term of the action; and therefore it cannot happen that formal and effective causality belong to the same form with respect to the same thing, for they include repugnant relationships.

13. Whether form can flow together with end into the same entity.—Again it is also clear that final and formal causality can in a certain way agree in the same form with respect to the same thing, but in a certain way cannot. For if they are compared to the same subject or supposit, they can excellently agree in the same thing; for the same form both is the end of matter and informs it, and the same beatific vision is the form of the intellect and its end and beatitude. And the reason is that the form itself, as informing, and its information, is the good and perfection of the subject which it informs; and therefore it can be compared to it at the same time in the notion of form and end. But if the comparison is made to the composite itself which is constituted through the form, then the same cannot be form and end with respect to the same, because the form is not the end of the composite, but rather the form is for the sake of the composite as for its end. But if they are compared to the action or generation, with respect to it too the same is form and end. In which sense Aristotle, to be cited below, seems to have said that end and form coincide in the same thing in number; yet under that respect, although the form is properly the end of generation, it is nevertheless not properly its formal cause, but only principle, as I was saying in the preceding section.

14. Whether efficient and end are conjoined in the same.—Whether matter admits some notion of end in its entity.—Moreover one must speak in almost the same proportion of the end and the efficient; for according to a certain notion of end they can belong to the same thing, but not according to another. For a twofold end, as we shall see below, is wont to be distinguished, namely the end for the sake of which the action comes about, or to which, or in whose favour and advantage it comes about; as in healing, the end for the sake of which is health; but the end to which is the man himself for whom health is procured. The former end, then, cannot be the same thing as the efficient cause, because it is its effect; but the latter end can excellently be the same thing as the efficient cause, for often the efficient operates for its own sake; and in this way God is at the same time the first efficient and the last end of his works. And according to these is easily understood that common saying of Aristotle, Physics II, c. 7: End and form coincide in the same in number; but end and efficient in the same not in number but in species; for he speaks of the end for the sake of which, or which through the action is formally intended and comes about; of which we have already said that it is distinguished from the agent as its effect, and therefore cannot be the same in number with it. But that it is the same in species happens in univocal agents, not in all, as Aristotle himself indicated. But how formal and final cause can be conjoined in the same thing in number has already been declared. But I add that some notion of end can also be conjoined in the same thing in number with the material cause; for the subject of accidents is both their material cause and their end; for, as I was saying, the proximate end of health to be procured is the man, and among other ends form is induced into matter for the sake of preserving matter itself; for, because the notion of end is founded in goodness, which is transcendental and is found in part in every entity, therefore some notion of end can be conjoined with any other cause whatever.

15. Whether the efficient can be the same as the matter.—It only remained to compare the efficient cause with the material, whether each notion can be conjoined in the same thing with respect to the same effect. And indeed, speaking of the material cause of natural substances, it is certain that the material and efficient cause cannot be conjoined in the same thing in order to such an effect, because matter cannot be the efficient principle of the form to be educed from it, and consequently not of the whole composite. But speaking of the material cause of accidents, there is greater doubt whether the same material cause can be the efficient of the same. But this efficiency can be understood as twofold: one, through natural resultance; and speaking of this there is no doubt that those causalities can be conjoined, and so it is commonly said that the soul, for example, has a threefold causality on its natural powers, namely final, material and efficient; and many think that this genus of activity is not repugnant even to prime matter on its proper property, which is quantity. The other efficiency is per se and through proper action, and of this there is greater difficulty; but it coincides with that question, whether everything which is moved is moved by another, or (what is the same) whether agent and patient are always distinguished, at least according to the proximate principles of acting and receiving, which we shall treat afterwards in disputing of the efficient cause.

Whether the division of cause into four genera is adequate

16. Instruments are to be placed under the efficient, not the material cause.—Concerning the third point, whether these four genera sufficiently divide cause, various difficulties are wont to be proposed about instrumental, dispositive and objective causes. But these and similar ones have no difficulty, for the instrumental cause is a certain species of efficient cause, as we shall see afterwards. Nor can it with any foundation be reduced to the material cause, as Philoponus falsely thought out, Physics II, text 27, unless perhaps we speak of the dispositions of matter, which are wont also to be called instruments; but these, unless they have efficiency, are in truth not instruments; but if they have efficiency, as such they are not dispositions nor do they pertain in any way to the material cause, but to the efficient, which they either help or whose place they take. But the dispositive cause is commonly reduced to the material, because it prepares matter for form. But this denomination seems to be only through a certain attribution; for, if we speak with propriety, a true disposition is a certain formal cause, for it does not dispose except by informing the subject; for heat in wood does not dispose to the form of fire except by formally heating the wood; but I speak of true and proper physical and positive disposition; for in the vulgar way any removal of an impediment whatever is wont to be called disposition, or any necessary condition whatever, as application to acting or something similar; and in these there is no true causality, but only per accidens.

17. Of what genus is the causality the object exercises on the power and its act.—I call the objective cause the object with respect to the power or act. In which object a twofold relationship can be considered: one of moving, the other of terminating. The former with respect to the cognitive power is efficient causality, whether the object is considered in so far as it moves by impressing a species or in so far as through the species it concurs to the act; but with respect to the appetitive power it is final causality, either proper and formal, as in the rational appetite, or material and imperfect, as in the sensitive, which we shall see afterwards. But under the latter respect some reduce the object to the final cause, because the power and act tend into it as into an end. Nor does it stand in the way that this relationship is essential, because it is not repugnant that some thing be essentially ordered to its end. Others reduce it to the formal cause, in so far as the object gives species to the act; for whatever gives species has the notion of form; but they say that it is not an intrinsic but an extrinsic form. But I would more willingly deny that the object under this notion exercises some true genus of causality, but only that of a pure specifying term, not through some true influx which would constitute a cause, but through the mere relationship of another to it. Nor did Aristotle ever mention that extrinsic formal cause, nor did he call the term of motion the cause of motion, although he said that it takes its species from it; and the same holds of one relative with respect to another, or of the term of a relation as such. Nor does St. Thomas speak otherwise, as may be seen in I-II, q. 1, a. 3. But these are easy, and almost about the mode of speaking.

18. Whether the exemplar is a genus of cause distinct from those enumerated.—The chief difficulty in this point is about the exemplar cause, which Plato adds to the four enumerated by Aristotle, as is evident from the Timaeus and Phaedo, and Seneca reports, in the cited Epistle 66. But of this matter, on account of its gravity, we shall institute a proper disputation. Now we briefly concede to Plato that the exemplar exercises true causality, which Aristotle was not ignorant of, for here, in enumerating form, he adds also exemplar; and therefore perhaps it is not necessary to increase the number on account of this cause, which we shall examine in the said place.

Whether the aforesaid division of cause is immediate

19. The division of cause into internal and external is higher than the aforesaid.—The most immediate division of cause into real, strictly, and intentional.—Concerning the fourth, that division can seem immediate, because Aristotle proximately divided cause into those four members. But nevertheless it must be said that that division is not immediate; for agreements among some of these members can easily be thought out, by reason of which other prior divisions of cause into fewer members are constituted. So, then, cause can first be divided into internal and external; the internal again into matter and form; of which it cannot be doubted that they agree peculiarly in the mode of causing; for they give being to the effect by conferring on it their own entity in number and internally composing it; but the efficient and the end cause far otherwise, and agree in this, that they do not intrinsically compose the effect, and therefore are commonly called extrinsic causes. Therefore in the notion of cause a common notion of matter and form can be abstracted which is not common to the other causes, and conversely; cause, therefore, is rightly divided immediately into intrinsic and extrinsic, and then the former into material and formal, but the latter into efficient and final. In another way too another more immediate division of cause could be thought out; for the three other causes besides the final agree in this, that they confer to the being of the effect through real influx, and therefore require real existence for their causalities, as we shall see afterwards; but the final cause flows intentionally, and therefore can cause before it really exists in itself. Cause, therefore, can rightly be divided immediately into real and intentional, taking that term real strictly in the former member; for, if it is taken in its whole breadth and transcendence, it also belongs to the final cause. And again real cause is divided into intrinsic, which is divided into matter and form, and extrinsic, which is the efficient, and by a peculiar reason and as it were by antonomasia can be called extrinsic; for, although the final cause compared to the formal and material is also extrinsic, nevertheless compared to the efficient it is in a certain way intrinsic; for the relationship to the end is more intrinsic to each thing, and in some is even essential.

Whether the four members of cause are atomic

20. Of the fifth point few things can be said in this place until we treat of the individual causes, and therefore it must briefly be said that this is not a division into the ultimate notions of cause; for under any one of those members various divisions can be given. For of the material cause one is pure potency, another only potency in a certain respect. Which is not only a material division (so to speak) according to the entity which is the cause, but is also formal in the notion of material cause. For it is of its formal notion that it be potency, and therefore according to the diverse notion of receptive potency there will be a diverse notion of material cause; which diversity can also be attended to from the effects; for the former is the material cause of substance, but the latter of accidents. Whence the former can be called material cause simply, but the latter in a certain respect, taking these words not from the entities of such causes but from the relationship to the effects; for as regards entity the material cause of accidents can be being simply, or an integral substance; but the material cause of substance can only be being in a certain respect; yet as regards causation or the relationship of cause, the latter causes being simply, the former in a certain respect. Again the material cause of substance is divided into the matter of corruptible or incorruptible substances; but the material cause of accidents can be divided either into corporeal and spiritual, or into proximate or remote, or into that which in itself is an accident, or which is a substance, either partial or integral, of all of which I shall speak in the next disputations. And in a proportional way form can be divided into substantial and accidental, and each member is subdivided into various forms according to the variety of composite substances and accidents. Likewise of the efficient and final cause there are very many divisions, which cannot be briefly recounted here, but in the proper disputations.

21. Why cause has been divided by the principal division neither into the highest nor into the lowest members.—You will say: if cause can immediately be divided into fewer members and remotely into more, why did Aristotle hand down that four-membered division rather than others? The answer is that by the very fact that that division is intermediate between those extremes it was more apt for handing down a doctrinal division. Especially because those members have more distinct and better known notions and modes of causing. Add that Aristotle did not altogether omit, but sufficiently indicated, both the agreements of these causes among themselves and their divisions, as is evident from the places cited.

Of what kind the division given is

22. In the sixth point all authors, rather supposing than proving or disputing, teach that that division of cause is analogous, and for that cause say that cause in common was not defined by Aristotle. Yet they do not sufficiently declare the mode or notion of this analogy, nor can it be declared by us until the notions of the individual causes are exactly treated. And therefore let us now suppose that that opinion is true, from the authority of the common opinion and from this general reason, that those modes of causes are common to the causes of accidents and of substances, which cannot be causes univocally, because they do not give being univocally; whence neither can the notion of effect be univocal in accident and substance; but the more exact declaration of this analogy I remit to the aforesaid place.