Tuesday, July 31, 2012

The Communicatio Idiomatum in St. Thomas Aquinas


Speaking of the God-Man:
The Communicatio Idiomatum in St. Thomas Aquinas

By Hilaire K. Troyer de Romero 
Copyright of Ite ad Thomam © 2012

In ST III.16, St. Thomas Aquinas discusses the question of what may be said about Christ.  We find this treatment in the Summa situated well after Aquinas’ thorough explanation of the Hypostatic Union because what may be said of Christ follows directly from the reality of the Hypostatic Union.  More specifically, the answer lies in the concept known as the communicatio idiomatum (or ‘communication of properties’).  This concept refers to an ontological, and not just logical, reality in Christ.  It can be defined as “the mutual exchange of divine and human properties in virtue of the Hypostatic Union.”[1]  As a logical reality, it is sometimes referred to as the ‘predication of properties’.  Sacred Scripture is replete with practical examples of this concept.[2]  Misunderstandings of the communicatio idiomatum have been at the heart of numerous Christological heresies such as Nestorianism and Monophysitism.  In this paper, I shall explain the principal elements of the communicatio idiomatum as presented by St. Thomas in ST III.16, beginning with its direct connection to the Hypostatic Union, and then a brief overview of the general rules that can be gleaned from St. Thomas’ treatment of this issue.

I.  Communicatio idiomatum and the Hypostatic Union
In the first article of question 16, St. Thomas begins his treatment by examining a fundamental Christological statement, “God is man.”  Here Aquinas establishes the immediate connection between the communicatio idiomatum and the Hypostatic Union.  He says,
Hence, supposing the truth of the Catholic belief, that the true Divine Nature is united with true Human Nature not only in person, but also in suppositum or hypostasis; we say that this proposition is true and proper, ‘God is man’ –not only by the truth of its terms, that is, because Christ is true God and true man, but by the truth of the predication.  For a word signifying the common nature in the concrete may stand for all contained in the common nature, as this word ‘man may stand for any individual man. And thus this word ‘God,’ from its very mode of signification, may stand for the Person of the Son of God, as was said in I.39.4.[3]

The “Catholic belief” referred to here is the Hypostatic Union.  For the sake of clarity I shall  review a few key terms found in the text above.  A suppostium or hypostasis is a bearer of properties, that is, any primary, or individual, substance that subsists in itself.  Aquinas refers to the suppositum or hypostasis as a “subsistence,” rather than as a mere substance, to express the connotation of “subsisting in itself.”[4]  A person is a particular kind of hypostasis or suppositum, namely, an individual substance of a rational nature.[5]  If we speak of an ordinary man, such as Aristotle, the suppositum or hypostasis is Aristotle himself; and that hypostasis has one human nature. The suppositum is the “who” (the quis est), namely Aristotle, and the nature is the “what” (quid est), namely a man. The two are not identical: Aristotle subsists in the human nature but we do not say that the nature is Aristotle, since this would be the same thing as saying that “Aristotle is humanity,” which is patently false.[6]  In the case of Christ, the suppositum or hypostasis is the quis est, the Divine Second Person, who subsists in the two natures, which are united substantially.[7] 
The communicatio idiomatum is the logical consequence of the perichoresis, or unity of the two natures in Christ, that results from the Hypostatic Union.[8]  That is, there is a natural interchange of properties between the two, because of the substantial union whereby the divine nature penetrates the Human Nature (without changing it) within the one Divine Personality or hypostasis that we call the Logos
Returning to the text at hand, the proposition “God is man” is a true statement and not merely in an analogical or metaphorical sense, in the way many heresies have interpreted it,[9]  precisely because of this Union of One Person and two natures.  In other words, when the subject of a sentence refers to the Second Person of the Trinity, it is possible to predicate of that subject the concrete properties of either nature, regardless of whether the term in the subject of the sentence connotes the divine nature or the human nature of Christ.  Since the Person of the Son of God for Whom this word ‘God’ stands, is a suppositum of human nature this word “man” may be predicated truly and properly of this word ‘God’.  Just as it is possible to say that “Socrates is man,” it is possible to say that “God is man,” when by “God” we mean “The Second Person.” In the statement “God is man,” the term ‘man’ is being predicated of the Divine Person, the Son of God as of the suppositum, and not of the divine nature itself.  This suppositum has both human and divine natures and hence both human and divine properties. The inverse statement, namely, “Man is God,” which Aquinas examines in article 2 of question 16, is also true because the term “man” can refer to any hypostasis that has a human nature.  So it can refer to the Second Person as the subject who, as I mentioned above, has both human and divine natures.  The statement would be false, of course, if the term ‘Man’ were to refer to all men, or any man other than Christ, such as Socrates, because then it would refer to a suppositum that possesses human nature only.

II. Corollaries
            Throughout question 16, Aquinas examines particular statements regarding Christ and asks whether or not they are true.  The result of his discussion of each statement is an overall framework, or a set of rules, that govern the communicatio idiomatum.  Below I address the primary rules that can be gleaned from question 16, which follow as logical consequences of the particulars of the Hypostatic Union.

A.  Only Concrete Terms of Concrete Subjects May Be Predicated of Either Nature
The most fundamental of these rules arises from the distinction between concrete and abstract terms, as St. Thomas explains in Article 1.  Concrete terms are those that refer to a property as it exists in a subject (man, carnal, animate, etc.), whereas abstract terms refer to properties in se, apart from a subject (divinity, humanity, truth, etc.).[10]  This means that the concrete term will signify the suppositum and abstract terms will signify the nature apart from the suppositum[11]
Aquinas, in his reply to Objection 2 in Article 1, says,
[I]n the mystery of the Incarnation the Natures, being distinct, are not predicated one of the other, in the abstract. For the divine nature is not the human nature. But because they agree in suppositum, they are predicated of each other in the concrete.[12]

 Fr. Garrigou-Lagrange formulates this rule thus:
[C]oncrete words of concrete subjects, both of natures and properties, generally speaking, can of themselves be predicated of either [nature]; but abstract words of abstract subjects cannot of themselves formally be predicated of either.[13]  

In other words, because concrete terms directly signify the suppositum and only indirectly the nature, they may be predicated of both the divine and human natures of Christ. Abstract terms, however, may only be predicated of both natures when they refer to divine properties, because only in the divine nature is there an identity between its properties and the nature itself.  For example, we may say that “Christ is Truth,” because the Second Person by virtue of His Divinity is indeed Truth itself. But we cannot say that “Christ is humanity” because in this case, the abstract term “humanity” is not identical with the divine suppositum.[14]

B. Reduplication Limits the Concrete Term to One Nature
        Another general rule is that we must exercise great care when there is an instance of reduplication such as in the statement, “Christ, as man is a creature.” In such instances the reduplication limits the concrete term to one particular nature so that what is predicated must be true of that nature by itself.[15]  For example, in article 10, Aquinas examines the truth of the statement, “Christ, as man, is a creature.” Here he affirms the statement because the reduplication “as man” means the concrete term “creature” refers to the human nature specifically, which is indeed created. 
It must however be borne in mind that the term covered by the reduplication signifies the nature rather than the suppositum, since it is added as a predicate, which is taken formally, for it is the same to say “Christ as Man” and to say “Christ as He is a Man.” Hence this is to be granted rather than denied: “Christ as Man is a creature.” But if something further be added whereby [the term covered by the reduplication] is attracted to the suppositum, this proposition is to be denied rather than granted, for instance were one to say: “Christ as ‘this’ Man is a creature.”[16]

Following the same guideline, in article 11, Aquinas points out that the statement “Christ, as man, is God” would be false, because the reduplication limits the concrete term “God” to the human nature alone which, though possessed by God in the Second Person, is not identical to God.  In some instances, the reduplication adds clarification, as in the first example found in article 10, and in others it makes an otherwise true statement false—as seen with the example from article 11.

C. Essential Properties of the Divine Nature Must Not be Predicated denominatively of Christ
A third rule is that adjectival names, in the concrete, that are derived cannot always be accurately predicated of Christ. For example, we cannot call Christ “lordly.” [17] Aquinas says in ST III.16.3:
Now ‘God’ and ‘Lord’ are predicated essentially of the Son of God; and hence they ought not to be predicated denominatively, since this is derogatory to the truth of the union. Hence, since we say ‘lordly’ denominatively from ‘lord’, it cannot truly and properly be said that this Man is lordly, but rather that He is Lord. [18] 

In other words, to call Christ ‘lordly’ would imply that He is not God because, to use the word ‘lordly’ with respect to Christ, either (a) is not fitting to Him who is Lord of Lords and therefore derogatory, and fails to show a true belief in the Hypostatic Union, or (b) is indicative of mere god-likeness, which is heretical, as the Church has already decreed many times since its condemnation of Arianism.

D. Phrases that Sound Heretical Should be Avoided
            Although the communicatio idiomatum does provide us with a great amount of freedom with regard to what we say about Christ, St. Thomas warns us against those statements that may be technically true but that can easily be interpreted in a heretical way.  For example, if we were to say, “Christ is a creature,” we run the risk of sounding like the Arians, who believed Christ was completely created and, therefore, less than the Father.  If what we mean to say is that Christ’s human nature is created, it would be better expressed with a clarification, such as that which Aquinas suggests in article 8: “And hence we must not say absolutely that Christ is a ‘creature’ or ‘less than the Father’; but with a qualification, viz. ‘in His human nature’."[19] In all cases, our use of language concerning Christ must be faithful to the reality of the Hypostatic Union.   Those predicates that appear ambiguous should always be clarified so as to avoid heretical interpretations.  It is always of the utmost importance that the language we use display logical congruence with the Hypostatic Union and the divinity of Christ.  Aquinas says, “As Jerome [Gloss, Ord. in Hosea 2:16] says, ‘words spoken amiss lead to heresy’; hence with us and heretics the very words ought not to be in common, lest we seem to countenance their error.”[20]

            In sum, the communicatio idiomatum is simply a consequence of the Hypostatic Union.  Because the two natures in Christ are united in the one suppositum, the Son of God, we may predicate what belongs to one nature of the other in the concrete. Yet the two natures are not intermingled or confused, so we must always ensure that the rules discussed above are always observed, so as not to imply a lack of unity or a confusion of the natures in Christ.  Joseph Pohle summarizes the communicatio idiomatum as a logical reality thus:
Formulated in logical terms, the ontological law underlying the communicatio idiomatum gives us the following rule of predication: “Whatever is predicated of the Divine Person of Christ according to His Divine Nature, can and must be predicated of the same Divine Person also in His human nature, and vice versa; but the predicates proper to the Divine Nature must not be assigned to the human nature, and vice versa.” The first part of this rule is based on upon the unity of the one Divine Person in two natures; the second, upon the fact that the two natures co-exist separately and in-confused in one Person.[21]

It is on the basis of this principle that the Church was able to develop her Christological doctrine and combat the heresies that have so relentlessly assailed her. St. Cyril of Alexandria in his third letter to Nestorius, expresses this in a profound way:
For we do not divide up the words of our Saviour in the gospels among two hypostases or persons. For the one and only Christ is not dual, even though he be considered to be from two distinct realities, brought together into an unbreakable union. In the same sort of way a human being, though he be composed of soul and body, is considered to be not dual, but rather one out of two. Therefore, in thinking rightly, we refer both the human and divine expressions to the same person. For when he speaks about himself in a divine manner as “he that sees me sees the Father,” and “I and the Father are one,” we think of his divine and unspeakable nature, according to which he is one with his own Father through identity of nature and is the “image and impress and brightness of his glory.” But when, not dishonouring the measure of his humanity, he says to the Jews: “But now you seek to kill me, a man who has spoken the truth to you,” again no less than before, we recognise that he who, because of his equality and likeness to God the Father is God the Word, is also within the limits of his humanity. For if it is necessary to believe that being God by nature he became flesh, that is man ensouled with a rational soul.... All the expressions, therefore, that occur in the gospels are to be referred to one person, the one enfleshed hypostasis of the Word. For there is one Lord Jesus Christ, according to the Scriptures.[22]


Council of Ephesus.
Garrigou-Lagrange, Reginald. De Christo Salvatore. Turin: R. Berruti, 1948.  <http://www.ewtn.com/library/theology/christ.htm>
Ott, Ludwig. Fundamentals of Catholic Dogma. St. Louis: B. Herder, 1964.
Pohle, Joseph; Arthur Preuss (trans., ed.). Christology: A Dogmatic Treatise on the Incarnation. St. Louis: B. Herder, 1916.
Tanquerey, Adolphe. A Manual of Dogmatic Theology. Translated by John J. Byrnes. New York: Desclee Company, 1969.
The Holy Bible (Douay- Rheims Version). London: Baronius Press, 2003.
Thomas Aquinas, Saint.  Summa Theologica. Notre Dame, IN: Ave Maria Press, 1981.

[1] Joseph Pohle, Christology (henceforth, “Pohle & Preuss”), p. 184. 
[2] Cf. John 8:58; Acts 3:15, 2:8; Romans 8:32, 6:3; I Cor. 2:8;
[3] Summa theologiae (henceforth, ST) III.16.1.
[4] Cf. ST I.29.2c: “In another sense substance means a subject or suppositum, which subsists in the genus of substance. To this, taken in a general sense, can be applied a name expressive of an intention; and thus it is called suppositum. It is also called by three names signifying a reality—that is, “a thing of nature,” “subsistence,” and “hypostasis,” according to a threefold consideration of the substance thus named. For, as it exists in itself and not in another, it is called “subsistence”; as we say that those things subsist which exist in themselves, and not in another.”
[5] Cf. ST I.I.29 Aquinas sometimes uses the term hypostasis to include the concept of “rational nature.” It seems that the terms suppositum, hypostasis, and person, are used interchangeably.
[6] Cf. ST III.2.2c.
[7] This by the grace of union that imparts the Personal Being of the Word on the human nature of Christ. Cf. Adolphe Tanquerey, A Manual of Dogmatic Theology, Vol. 2, p. 28.
[8] Cf. Pohle & Preuss, p. 184: “Though practically identical with Perichoresis, the Communication of Idioms may more appropriately be regarded as an effect thereof.”
[9] St. Thomas references the errors of Photinus and Nestorius specifically in ST III.16.1.
[10] Adolphe Tanquerey, A Manual of Dogmatic Theology, Vol. 2, p. 28.
[11] Cf. Ludwig Ott, Fundamentals of Catholic Dogma, p. 161:  “communication idiomatum fit in concreto, non in abstracto.”
[12] ST III.16.1. Cf. article 5: “Now concrete words stand for the hypostasis of the nature; and hence of concrete words we may predicate indifferently what belongs to either nature--whether the word of which they are predicated refers to one nature, as the word “Christ,” by which is signified “both the Godhead anointing and the manhood anointed”; or to the Divine Nature alone, as this word “God” or “the Son of God”; or to the manhood alone, as this word “Man” or “Jesus.” Hence Pope Leo says (Ep. ad Palaest., cxxiv): “It is of no consequence from what substance we name Christ; because since the unity of person remains inseparably, one and the same is altogether Son of Man by His flesh, and altogether Son of God by the Godhead which He has with the Father.”
[13] Garrigou-Lagrange, Christ the Saviour, Ch. 18, Subsection: “The Consequences Of The Union As Regards Those Things That Belong To Christ In Himself”.
[14] Ibid.: “It must be observed concerning this communication that concrete names, such as God, man, in opposition to abstract names, such as Godhead, humanity, signify directly the suppositum, and indirectly the nature. For “God,” signifies the suppositum that has the divinity, and “man” signifies the suppositum that has the humanity. If, therefore, the suppositum is the same for the two natures, then it is true to say: “God is man,” although it is false to say: “The Godhead is the humanity.” Thus we shall see that the generally accepted rule, namely, concrete words of concrete subjects, both of natures and properties, generally speaking, can of themselves be predicated of either; but abstract words of abstract subjects cannot of themselves formally be predicated of either. Thus we shall see that we cannot say the Godhead is the humanity or that God is the humanity, or that the humanity is God. Therefore we must take great care to distinguish between abstract terms and concrete terms. The abstract term signifies the nature separated from the subject, for example, humanity. The concrete term signifies the nature as existing in the subject, for example, man. Hence this distinction between concrete and abstract term is of great importance in distinguishing between the nature and the suppositum, since the nature is an essential part of the suppositum. There is the same distinction between “being” as a noun and “being” as a participle, or between the reality and the real itself.”
[15] Ludwig Ott,  Fundamentals of Catholic Dogma, p. 161.
[16] ST III.16.10.c.
[17] Adolphe Tanquerey, A Manual of Dogmatic Theology, Vol. 2, p. 28.
[18] ST III.16.3; cf., Pohle & Preuss, pp. 188-189; Adolphe Tanquerey, A Manual of Dogmatic Theology, Vol. 2, p. 28.
[19] ST III.16.8c.
[20] Ibid.
[21] Pohle & Preuss, p. 186.
[22] Council of Ephesus, “Letter of Cyril to Nestorius” (Cum salvator noster).

Friday, July 27, 2012

The Ultimate Stimulus Package: Children (nobility.org)


Link to nobility.org article.

Thursday, July 26, 2012

The Principle of Predilection: "Nothing would be greater if God did not will it more good."


Summa theologiae I.20.3c: Does God Love All Equally? 

I answer that, since to love a thing is to will it good, in a twofold way anything may be loved more, or less. In one way on the part of the act of the will itself, which is more or less intense. In this way God does not love some things more than others, because He loves all things by an act of the will that is one, simple, and always the same. In another way on the part of the good itself that a person wills for the beloved. In this way we are said to love that one more than another, for whom we will a greater good, though our will is not more intense. In this way we must needs say that God loves some things more than others. For since God's love is the cause of goodness in things, as has been said (2), no one thing would be better than another, if God did not will greater good for one than for another.

Respondeo dicendum quod, cum amare sit velle bonum alicui, duplici ratione potest aliquid magis vel minus amari. Uno modo, ex parte ipsius actus voluntatis, qui est magis vel minus intensus. Et sic Deus non magis quaedam aliis amat, quia omnia amat uno et simplici actu voluntatis, et semper eodem modo se habente. Alio modo, ex parte ipsius boni quod aliquis vult amato. Et sic dicimur aliquem magis alio amare, cui volumus maius bonum; quamvis non magis intensa voluntate. Et hoc modo necesse est dicere quod Deus quaedam aliis magis amat. Cum enim amor Dei sit causa bonitatis rerum, ut dictum est, non esset aliquid alio melius, si Deus non vellet uni maius bonum quam alteri.

Saturday, July 21, 2012

Pontifical Catholic University of Peru Stripped of its Pontifical Status by Vatican


Link to CNA article.

Friday, July 20, 2012

Why God Cannot Change: St. Thomas' Arguments


From Summa theologiae I.9.1: “Whether God is altogether immutable?”

“I answer that, from what precedes, it is shown that God is altogether immutable.

First, because it was shown above that there is some first being, whom we call God; and that this first being must be pure act, without the admixture of any potentiality, for the reason that, absolutely, potentiality is posterior to act. Now everything which is in any way changed, is in some way in potentiality. Hence it is evident that it is impossible for God to be in any way changeable.

Secondly, because everything which is moved, remains as it was in part, and passes away in part; as what is moved from whiteness to blackness, remains the same as to substance; thus in everything which is moved, there is some kind of composition to be found. But it has been shown above that in God there is no composition, for He is altogether simple. Hence it is manifest that God cannot be moved.

Thirdly, because everything which is moved acquires something by its movement, and attains to what it had not attained previously. But since God is infinite, comprehending in Himself all the plenitude of perfection of all being, He cannot acquire anything new, nor extend Himself to anything whereto He was not extended previously. Hence movement in no way belongs to Him. So, some of the ancients, constrained, as it were, by the truth, decided that the first principle was immovable.”

1st Argument in Syllogistic Form (From the notion of pure act)
MajorWhatever is pure act is immutable.
MinorThe unmoved mover is pure act.
Conclusion: Therefore, God is immutable.

Defense of the Argument
Proof of the Major: The unmoved mover is pure act without potency--if it had potency, that potency would have to be brought to act by something else. (Implicit in the ‘First Way’, ST I.2.3c.)
Proof of the Minor: motion or change is a transition from potency to act; whatever is not in potency cannot undergo this transition.

2nd Argument in Syllogistic Form (From the notion of motion)
Major: Whatever is in motion is a composite.
Minor: God is not a composite.
Conclusion: Therefore, God is immutable.

Defense of the Argument
Proof of the Major: Whatever is in motion must partly change and partly remain the same.  This implies composition of parts or aspects.
Proof of the Minor: It was demonstrated in ST I.3.7c.

3rd Argument in Syllogistic Form (From the notion of perfection)
Major: Whatever is in motion acquires a new perfection.
Minor: God cannot acquire a new perfection.
Conclusion: Therefore, God is immutable.

Defense of the Argument
Proof of the Major: Whatever is in motion must partly change and partly remain the same.  This implies composition of parts or aspects.
Proof of the Minor: God's perfection is infinite, as was demonstrated in ST I.7.1c.

Wednesday, July 18, 2012

Quaeritur: Premotion in Aquinas and His Commentators


Quaeritur: I am interested in the topic of pre-motion within the thought of St. Thomas and his commentators, specifically Garrigou-Lagrange.  I was wondering if you could point me in the right direction for some information on this within the corpus of Thomas himself and in his commentators.  A friend of mine was giving me some brief explanations of this topic and I was interested, but have not been able to make a lot of progress.

Respondeo: Below are a couple of texts in Aquinas that clearly teach premotion (without calling it such---the term is Báñez's).  But, in addition, I wholeheartedly recommend Garrigou's own Predestination, which is really the best work out there on the topic.  After that, I would recommend tackling Báñez's commentary on the Prima Pars.  Both are available from ITOPL.  Báñez's commentary, of course, remains untranslated, but Garrigou's book is available in English translation.

Quaestiones disputatae de malo 6.1 ad 3 (my translation):

God immutably moves our will on account of the efficacy of His moving power, which cannot fail; but on account of the nature of the will that is moved, which relates indifferently to diverse things, necessity is not introduced; just as in all things divine providence operates infallibly; and yet from contingent causes effects are contingently produced, insofar as God moves all things proportionately, each being according to its mode.

Deus movet quidem voluntatem immutabiliter propter efficaciam virtutis moventis, quae deficere non potest; sed propter naturam voluntatis motae, quae indifferenter se habet ad diversa, non inducitur necessitas, sed manet libertas; sicut etiam in omnibus providentia divina infallibiliter operatur; et tamen a causis contingentibus proveniunt effectus contingenter, in quantum Deus omnia movet proportionabiliter, unumquodque secundum suum modum.

ST I.83.1: Whether man has free-will? (My translation, emphasis added).

[Argument 3]. Further, that is free which is cause of itself, as is said in the first book of the Metaphysics [ch. 2]. What is moved by another, therefore, is not free. But God moves the will, for it is said in Proverbs 21[:1], "The heart of the king is in the hand of the Lord; whithersoever He will He shall turn it," and in Philippians 2[:13], "It is God Who worketh in you both to will and to accomplish."

To the 3rd, it must be said that the free will is a cause of its motion, because man through his free will moves himself to acting. But it does not necessarily belong to freedom that it be its own first cause. God, therefore, is the first cause that moves both natural and voluntary causes. And just as, by moving natural causes, he does not take away the fact that their acts are natural; so by moving voluntary causes, he does not take away the fact that their actions are voluntary, but rather makes this very thing [i.e., being voluntary] in them, for he operates in each thing according to what is proper to it.

Praeterea, liberum est quod sui causa est, ut dicitur in I Metaphys. Quod ergo movetur ab alio, non est liberum. Sed Deus movet voluntatem, dicitur enim Prov. XXI, cor regis in manu Dei, et quocumque voluerit vertet illud; et Philipp. II, Deus est qui operatur in nobis velle et perficere. Ergo homo non est liberi arbitrii.Ad tertium dicendum quod liberum arbitrium est causa sui motus, quia homo per liberum arbitrium seipsum movet ad agendum. Non tamen hoc est de necessitate libertatis, quod sit prima causa sui id quod liberum est, sicut nec ad hoc quod aliquid sit causa alterius, requiritur quod sit prima causa eius. Deus igitur est prima causa movens et naturales causas et voluntarias. Et sicut naturalibus causis, movendo eas, non aufert quin actus earum sint naturales; ita movendo causas voluntarias, non aufert quin actiones earum sint voluntariae, sed potius hoc in eis facit, operatur enim in unoquoque secundum eius proprietatem.

Tuesday, July 17, 2012

The Best Manual on Ascetical and Mystical Theology (Free Download)

Royo Marin, Antonio - Teologia de La Perfeccion Cristiana 01

As can be seen from his letter to the author (p. xxxv), Fr. Garrigou-Lagrange highly praises this manual, written in Spanish by his confrere, Antonio Royo Marín, OP.  It is also said that Fr. Garrigou considered this manual to better than his own The Three Ages of the Interior Life and that he recommended it more highly.  

Here is the 1962 edition (later editions contain  a few quotations and doctrines taken from Vatican II and post-conciliar documents, but retain the scholastic format and essential plan of the work).

Sunday, July 15, 2012

Notes on The 24 Thomistic Theses (Hugon's Commentary): Thesis One


For an introduction to this series of posts, click here.

THESIS ONE: “Potency and act divide being in such a way that whatever is, is either a pure act, or else coalesces necessarily from potency and act as from its first and intrinsic principles.” 

(Potentia et actus ita dividunt ens, ut quidquid est, vel sit actus purus, vel ex potentia et actu tamquam primis atque intrinsecis principiis necessario coalescat.)

The footnote to the thesis (in the original ecclesiastical document) refers to the following texts of St. Thomas: 

Summa theologiae Ia, Q.77, a.1: “potency and act divide being and every kind of being....” 

In Metaph. Book VII, Lect. 1: “Now essential being, which exists outside the mind, is divided in two ways, as has been stated in Book V; for it is divided, first, into the ten categories, and second, into the potential and the actual.” 

In Metaph. Book IX, Lect. 1: “the Philosopher’s aim here is to establish the truth about being as divided into potency and actuality.” 

(See also In Metaph. Book IX, Lect. 9.)


Hugon begins his discussion of Thesis One by introducing the distinction between potency and act, and then dividing the notion of potency into its kinds. 

That which is in potency can be, whereas that which has passed from what can be to what is, is in act. The good professor of metaphysics is a philosopher in act, whereas the newborn is a philosopher in potency. 

Now, ‘potency’ can be understood in two ways: objective, or merely logical potency, and subjective potency. We must be careful here not to read into this distinction our modern understanding of the terms “objective” and “subjective”; in fact, the real meaning here is practically the opposite of what our modern terminology might incline us to think.  Subjective potency is the potency that is in a real subject—meaning real a thing in the world, whereas “objective” potency refers to potency insofar as it is an object of the intellect, and thus, it does not refer to a real potency in a real thing, but to some mere possibility, to what can be the case, but is not. A horse that can fly is an objective potency, or merely logical possibility, whereas a bird’s capacity to fly is a real or subjective potency. 

Hugon then makes a further division within subjective potencies: some subjective potencies come 'out of' something, and are called active potencies, such as fire’s capacity to burn or to produce heat, whereas others are 'in something', and are called passive potency, such as water’s capacity to be heated. The first is a perfection, whereas the latter represents an imperfection. For this reason, the first is compatible with God, Who is Pure Act, whereas the latter is not. God has all active potencies (and hence we say He is omnipotent), but he has no passive potency (and hence we say he is impassible). 

Hugon then proceeds to explain motion (or ‘change’) as the passing from potency to act. In connection with this, he makes two important points. First, that which is being moved is in potency insofar as it is being moved. It does not yet possess the act towards which it is being moved; once it reaches that act, which is the goal, so to speak, it is no longer in motion. Yet that which moves, imparts act, and is thus in act—for nothing can give an act that it does not possess. Hence, the mover is in act, while the moved is in potency. Take, for instance, water in a pot being heated by fire. The fire is hot in act, whereas the water in the pot is hot in potency while it is being heated. The second important point is a corollary of the foregoing: the mover is necessarily distinct from the moved. Stated negatively, nothing can move itself. This obvious and seemingly superfluous point is the crux of Aquinas’ first way of proving God’s existence. 

Hugon then moves on to consider the notion of ‘pure act’. He explains, along the lines of the thesis, that there are two ways in which act can be limited, and thus fail to be pure act: it can be received by potency, as the soul is received by the body, or it can be modified or perfected by further act, as when an angel, though immaterial, receives its being, its faculties, and its operations, which are perfections, and hence the angel is in potency to them. In the case of God, however, ‘pure act’ means that such act neither receives nor is received; it is pure perfection without limit. In everything outside of God, there is always some admixture of potency and act; these two, potency and act, are the first and intrinsic principles of creatures. Hugon finally notes the relation between the Aristotelian-Thomistic doctrine of potency and act to that of the ten categories. First, potency and act represent the most general division of being (ens), omne ens et omne genus entis. That is to say, the composition of potency and act is common to all categories, both substance and the accidents, such that substantial being is divided into substantial potency and substantial act, and accidental being is divided into accidental potency and accidental act. This allows us to understand the axiom, potentia et actus sunt in eodem genere, potency and act are in the same genus: substantial act can only be received by substantial potency, and accidental act can only modify accidental potency.

Friday, July 13, 2012

Should Classrooms Be Coed? (TFP Article)


“Many of those boys who scored proficient in the [experimental] all-boys classes had previously been labeled ‘ADHD’ [Attention Deficit Hyperactivity Disorder] or ‘ESE’ [Exceptional Student Education] in coed classes.”  

Glad someone other than the Opus Dei has come to that realization!

Link to TFP article.