Monday, April 20, 2015


Commentary on actus essendi

Text no. 13



Commentary on 

Expositio in librum Boetii De hebdomadibuslecture 2

(Quotations from the writings of 
C. Fabro, P. Ruffinengo and D. Bradshaw) 


In his commentary on Boethius’s De hebdomadibus Aquinas uses the expression actus essendi twice, in lecture 2: “Sicut possumus dicere de eo quod currit sive de currente quod currat inquantum subiicitur cursui et participat ipsum, ita possumus dicere quod ens sive id quod est sit inquantum participat actum essendi. (…) Sed id quod est, accepta essendi forma, scilicet suscipiendo ipsum actum essendi, est, atque consistit, idest in seipso subsistit; non enim ens dicitur proprie et per se nisi de substantia cuius est subsistere.

Since the publication of Cornelio Fabro’s works on participation (in 1939 and 1960), the In librum Boetii De hebdomadibus expositio has received considerable attention. Thus, before offering my own commentary on the context surrounding the text where Aquinas explicitly employs the expression actus essendi in his In De hebdomadibus, I shall first review some of the comments that have been offered by other authors in the relatively recent period since Fabro’s books.

E. Cornelio Fabro, Pier P. Ruffinengo and David Bradshaw

In his Partecipazione e Causalità, Cornelio Fabro directs attention to the fact that in order to explain the axiom diversum est esse et id quod est, Aquinas introduces a number of terms which were not present in the De hebdomadibus of Boethius, such as ens, currens, currere, and actus essendi. According to Fabro, the expression essendi forma—which was crafted by Boethius with refined expertise, Fabro remarks—became for Aquinas the ipse actus essendi. Fabro considers that by the time Aquinas composed the commentary on Boethius’s De hebdomadibus the teachings presented in the commentary were well established doctrines in Aquinas’s mind.

Footnote: See Cornelio Fabro, Partecipazione e Causalità, (Torino: Società Editrice Internazionale, 1960), 204-205: “Nel suo commento San Tommaso riporta l’esse all’ens, ciò ch’è assente nel troppo conciso testo boeziano. (…) [Nel]l’esempio indicativo che segue, assente in Boezio e frequente in San Tommaso, della distinzione fra currere e currens: currere indica l’atto indeterminato, currens il soggetto (particolare) in atto… (…) [C]iò che Boezio rende con raffinata perizia con essendi forma diventa per San Tommaso l’ipse actus essendi.” See also C. Fabro, La Nozione Metafisica di Partecipazione, (Torino: Società Editrice Internazionale, 1950), Introduzione, in fine: “Il Commento a Boezio suppone una dottrina ormai stabilita.”

To be noted also is the fact that although Aquinas sometimes goes so far as to use the expression natura essendi, he clearly opted for not using the Boethian expression forma essendi. Only once in his writings, in the context of commenting on the text from Boethius, does Aquinas use the expression essendi forma. This fact is not reported by Fabro, and, to the best of my knowledge, other scholars who have also written on the subject of Aquinas’s interpretation of the Boethian forma essendi have overlooked this fact as well.

Under the guidance of Cornelio Fabro, Pier Ruffinengo has carefully studied the issue of the shift from forma essendi to actus essendi which Aquinas explicitly made in his commentary on Boethius’s De hebdomadibus. Ruffinengo suggests that the originality of Aquinas consists in having shifted from the understanding of esse as forma of the Neoplatonic thinkers to the understanding of esse as actus. The actus essendi of Aquinas is not another forma; rather, it is actus formae. Ruffinengo’s observation is in line with what is generally recognized to be the distinctive contribution of Aquinas to the philosophy of being, namely, the discovery that in subsisting extramental things all acts are in reality potency with respect to the metaphysical principle of actus essendi instantiated by the subsisting thing. Aquinas understands the metaphysical principle of actus essendi to be the actualitas omnium actuum and the perfectio omnium perfectionum.

Footnote: See Pier P. Ruffinengo, “L’ipsum esse non e ancora l’actus essendi di San Tommaso,” Aquinas: Rivista Internazionale di Filosofia 38 (1995): 631-635: “Ed è pure un fatto che Boezio intende Dio come Esse, per quanto nel senso di Forma Essendi (De Trinitate, II, 18-20). Ora sta proprio qui la novità di Tommaso, di intendere cioè Dio non come Forma Essendi, ma come Ipse Actus Essendi subsistens. (…) Però quello che io ho inteso sottolineare al termine del mio excursus storico-teoretico sul pensiero greco e sul neoplatonismo latino fino al sec. XII, … è il passaggio dall’esse inteso come forma all’esse intuito da Tommaso come actus. (…) L’essenziale è che questo esse, sia in senso generale, sia applicato a Dio, prima di Tommaso era sempre stato inteso come una forma accanto alle altre (e Dio era la Forma suprema). L’originalità assoluta e decisiva di Tommaso consiste nell’averlo inteso come actus, actus formae, omnium formarum. E Dio per Tommaso è Ipsum Esse, nel senso di Ipse Actus Essendi subsistens. Insomma: l’ipsum esse dei neoplatonici non è ancora l’actus essendi di S. Tommaso d’Aquino.” See also, P. Ruffinengo, “Giustificazione critica dell’actus essendi e problema del fondamento,” in Quaderni di  Velia, no. 3: Veritatem in Caritate, ed. Giuseppe M. Pizzuti (Potenza: Edizioni Ermes, 1991), 223-242; P. Ruffinengo, Le cose, il pensiero, l’Essere: Fodazione critica della metafisica, (Genova: Marietti, 1988), 140-149; P. Ruffinengo, Ontonòesis: Introduzione alla metafisica, (Genova: Marietti, 2002), 62-95; P. Ruffinengo, Essere oltre l'essente: Ricerca storico-teoretica, (Ancona: Il lavoro editoriale Casa Editrice, 2013); and P. Ruffinengo, “Differenza Ontologica e Actus Essendi: con San Tommaso oltre Heidegger,” Divus Thomas 116, no. 2 (2013): 171-209.

In this regard, David Bradshaw comments that it is remarkable that without any knowledge of the Neoplatonic antecedents of the Boethian axioms (Plotinus, Porphyry, the Anonymous Commentary on the Parmenides, and Marius Victorinus), Aquinas was able to find in the De hebdomadibus an inspiration for his own conception of the metaphysical principle of actus essendi.

Footnote: See David Bradshaw, Aristotle East and West, (Cambridge: Cambridge University Press, 2004), 114-118; and D. Bradshaw, “Neoplatonic Origins of the Act of Being,” The Review of Metaphysics 53 (1999): 383-401. Quoting from Pierre Hadot’s “Forma Essendi: interprétation philologique et interprétation philosophique d'une formule de Boèce” (Les Études Classiques 38 [1970]: 154-155), Bradshaw remarks that Hadot pays what seems just tribute in the remark that Aquinas’s philosophical genius guided him and enabled him to get to the bottom of Boethius’s formulae by intuition.

For more on Boethius, see Claudio Moreschini, A Christian in Toga: Boethius: Interpreter of Antiquity and Christian Theologian (Göttingen: Vandenhoeck and Ruprecht, 2014), 74-76; Christophe Erismann, “The Medieval Fortunes of the Opuscula Sacra,” in The Cambridge Companion to Boethius, ed. John Marenbon (Cambridge: Cambridge University Press, 2009), 155-177; John Marenbon, Boethius, (Oxford: Oxford University Press, 2003), 90; and Ralph McInerny, Boethius and Aquinas, (Washington, D.C.: Catholic University of America Press, 2012), 161-253.


Monday, April 13, 2015


Commentary on actus essendi

Text no. 13



Commentary on 

Expositio in librum Boetii De hebdomadibuslecture 2

(Quotations from the writings of R. McInerny)  


In his commentary on Boethius’s De hebdomadibus Aquinas uses the expression actus essendi twice, in lecture 2: “Sicut possumus dicere de eo quod currit sive de currente quod currat inquantum subiicitur cursui et participat ipsum, ita possumus dicere quod ens sive id quod est sit inquantum participat actum essendi. (…) Sed id quod est, accepta essendi forma, scilicet suscipiendo ipsum actum essendi, est, atque consistit, idest in seipso subsistit; non enim ens dicitur proprie et per se nisi de substantia cuius est subsistere.

Since the publication of Cornelio Fabro’s works on participation (in 1939 and 1960), the In librum Boetii De hebdomadibus expositio has received considerable attention. Thus, before offering my own commentary on the context surrounding the text where Aquinas explicitly employs the expression actus essendi in his In De hebdomadibus, I shall first review some of the comments that have been offered by other authors in the relatively recent period since Fabro’s books.


D. Ralph McInerny

From the passages from Ralph McInerny’s Boethius and Aquinas reported below we take the following points:

(a) McInerny emphasizes that both Boethius and Aquinas explicitly affirmed that the axiom diversum est esse et id quod est is a self-evident axiom.

(b) McInerny underscores the philosophical nature of Boethius’s De hebdomadibus.

Here are excerpts from Ralph McInerny’s Boethius and Aquinas, (Washington, D.C.: Catholic University of America Press, 1990):

“That the diversity between esse and id quod est is self-evident is one of the great overlooked claims of De hebdomadibus and of Thomas’s commentary on it” (Boethius and Aquinas, xiv).

De hebdomadibus makes no appeal to the Catholic faith. Indeed, it proceeds on the basis of truths which need only be heard to command assent” (Boethius and Aquinas, 130).

“(3a) Omni composito aliud est esse, aliud ipsum est. (3b) Omne simplex esse suum et id quod est unum habet. This is the order in which the axioms turning on the one occur in Thomas [in his commentary on Boethius’s De hebdomadibus,] and, as we shall see, it is fitting that they should, whatever the textual situation might be. In any case, it is clear that simple and composed are modes of oneness. Moreover, we are moving from a diversity in the conceptual or intentional order, a diversity in the realm of meanings and accounts of words, to statements about the presence or lack of a corresponding diversity in the things to which the words refer” (Boethius and Aquinas, 211-212).

“Not only is there a difference of account between ens or quod est and esse, in the composite things of this world there is a real difference as well. Here we have a locution that led to talk of the Real Distinction, and the context makes what the contrast intended is. ‘Est autem considerandum, quod ea quae supra dicta sunt de diversitate ipsius esse et eius quod est, est secundum ipsas intentiones; hic autem ostendit quomodo applicetur ad res’ (n. 31). Whether we are speaking of simple or composite things, when we use the terms ens and esse they will have different accounts, different modes of signifying, and certain restraints will follow on those modes. Now this poses a problem when what we are talking about are simple things. We have no choice but to use a language which is suggestive of complexity, and the reason is that our language is fashioned to express what we first know and what we first know are complex, composite, things” (Boethius and Aquinas, 212).

Footnote: This was St. Thomas’s point in Summa theologiae, [I], q. 13, a. 1, ad 2m.

“‘Est ergo considerandum, quod sicut esse et quod est differunt in simplicibus secundum intentiones, ita in compositis differunt realiter’ (n. 32)” (Boethius and Aquinas, 212).

“A question we can put at this point is this. Is it the identification of esse and quod est in simple things which is taken to be evident and their non-identity in composite things that requires showing, or the reverse? The remark of Thomas we have just recalled makes it clear what his view is. The complexity in our language is a sign of what is most knowable by us, namely, composite things. The major concern then would be to guard against attributing to the things being spoken of the complexity of our talk about them” (Boethius and Aquinas, 212).

“The question would be unintelligible if we had not seen that the status of being an axiom, a communis animi conceptio, does not exempt from being dependent for its manifestation on another. But, needless to say, the manifestation of an axiom could scarcely be a matter of demonstration or proof, since that would require a middle term and axioms are immediate. And what Thomas tells us is that the real diversity of quod est and esse in composite things is clear from the forgoing: quod quidem manifestum est ex praemissis. What are the elements of this manifesting?” (Boethius and Aquinas, 212-213).

1. Dictum est enim supra quod ipsum esse

a. neque participat aliud, ut eius ratio constituatur ex multis;
b. neque habet aliquid extraneum admixtum, ut sit in eo compositio accidentis;
c. et ideo ipsum esse non est compositum.

2. Res ergo composita non est suum esse.

[In the footnote McInerny provides the following translation:] “It was said above that (1) existence itself (a) neither participates in anything, such that its account would be composed of many (b) not has anything extraneous mixed with it, such that there is in it a composition with accidents, (c) therefore existence itself is not composed. (2) Therefore, the composed thing is not its existence” (lectio 2, n. 32).

“Would it make any sense to speak of this as a proof of the real distinction between esse and quod est in composite things? There is one ideo and one ergo in the sequence, which might lead the unwary to think a demonstration is being claimed. But clearly this is not the case. It seems obvious enough that 1a and 1b mention the kind of complexity not to be found in ipsum esse and thus enable us to know what would be meant by calling it simple. They could be called a conjunction of modi tollentes. If something participates in another such that its account is composed of many elements, it is composite. But this is not the case with ipsum esse, so it is not composite. And so too with 1b. But what are we to make of the ergo in 2? If ipsum esse is simple, as has been shown, it follows that a composite thing is not existence” (Boethius and Aquinas, 213).

Footnote: Whether or not the translation of the Posterior Analytics included in PL 64 is that made by Boethius, he would have been aware of chapter 7, Book Two of that work. “At vero si demonstrabit quid est, et quia est, et qualiter eadem ratione demonstrabit, definito enim unum aliquid, et demonstratio, id autem quod est et quid est homo, et esse hominem, aliud est. Postea per demonstrationem dicimus necessarium esse demonstrare omne quia est, nisi substantia sit, esse autem non substantia ulla est, non enim est genus, quod est, demonstratio itaque erit quia est, quod quidem et non faciunt scientiae. (…)” PL 64, 748D-749A.

“But 2 says more; the composite thing is not its existence. [The statement in] 2 can seem to be merely 1c converted: ipsum esse non est compositum converts to compositum non est ipsum esse. The ergo then would simply be the sign of the converted form being yielded by the original proposition” (Boethius and Aquinas, 213-214).

Footnote: Boethius wrote extensively of conversion of propositions as well as of the relation of propositions on the Square of Opposition, and used sequuntur and igitur lavishly to speak of contradictories, such that if the universal affirmative is true, then the particular negative is false. See, for example, PL 64, 773 ff.

“But, again, 2 is not just the converted form of 1c. How should we understand this?” (Boethius and Aquinas, 214).

“The most straightforward way would be this. A composite thing cannot be identified with one of its components, particularly one that has just been shown to be incomplex. But quod est is a compound of what receives existence and the existence received. If this complexity were only in the intentional order, the thing would not be composite, but simple. This enables us to understand the relative swiftness with which Thomas establishes the sense of (3a:) [Omni composito aliud est esse, aliud ipsum est]. What is being asserted is assented to straight off when we know what is being said” (Boethius and Aquinas, 214).

“Anyone who knows what a composite thing is will know that its existence is diverse from what it is. A composite thing is something that has come into being as a result of a change and is thus composed of matter and form. For it to be is for the form to inhere in, to actuate, the matter. But for the form so to inhere in the matter is not what the form is, nor what the matter is, nor what the conjunction of them is. The form explains the kind of existence the composite thing enjoys, but it is not the efficient cause of its own inherence in the matter. For a composite thing to be is for its parts to continue to cohere, for its form to inhere in its matter. For it thus to be in act, to be actual, is what is meant by its existence, suum esse(Boethius and Aquinas, 214).

“That nothing more arcane than this is in play is clear when we go on to the comment on (3b:) [Omne simplex esse suum et id quod est unum habet]. If there are simple things, there can be in them no real diversity of quod est and esse. If there were, they would be composite and not simple. This is not a proof that there are such simple things. Indeed, so far as the De hebdomadibus is concerned, there is only one such simple thing, the First Good, the creator of complex things and the explanation of both their existence and their goodness” (Boethius and Aquinas, 214-215).

“We can thus see the appropriateness of the ordering of the axioms bearing on the composite and the simple as St. Thomas had it. The reverse order might suggest that, while there is no difficulty understanding the identity of quod est and esse in simple things, problems arise when we try to grasp their diversity in complex things. The fact of the matter is, we have no philosophical warrant for talking of simple thing(s) except on the basis of a proof that they exist. If they exist, there are axiomatic truths about them, such as the one mentioned at the outset, namely, that incorporeal things are not in place. But our knowledge and our language and our certainties commence in the realm of the complex. As we have several times recalled, that is a fundamental reason why our language suggests complexity. The problem is to stretch our knowledge and our language to the incomplex when we have established, on the basis of truths about the complex, that such things exist” (Boethius and Aquinas, 215).

“When Thomas turns to (3b:) [Omne simplex esse suum et id quod est unum habet], he reminds us of the obvious, namely that our notion of simple things is arrived at by negating composition in them. Since there is composition and composition, there are degrees of simplicity. Something can be called simple because it lacks a certain kind of complexity, yet involve another kind. Typically, Thomas begins with corporeal things that are relatively simple, as the elements are simpler bodies than mixed bodies whose composition involves contraries. Nonetheless, the basic composition in physical bodies is that of matter and form, since this follows on the very fact that they are physical or natural, that is, have come into being as the result of a change. Matter is the subject which persists through the change, and form is the determination it receives as the result of the change” (Boethius and Aquinas, 215-216).

“By comparison with physical substance then, if there were a substance that is form alone, it would be simple. Thomas uses the plural, as Boethius did not, since such subsistent forms admit of variety and plurality. “If then some forms were found not to be in matter, each would be simple insofar as it lacked matter, and thus quantity which is a disposition of matter, but because each form would be determinative of existence, none of them would be existence, but all would have existence” (Boethius and Aquinas, 216).

Footnote: “Si ergo inveniantur aliquae formae non in materia, unaquaeque earum est quidem simplex quantum ad hoc quod caret materia, et per consequens quantitate, quae est dispositio materiae, quia tamen quaelibet forma est determinativa ipsius esse, nulla earum est ipsum esse, sed est habens esse” (lectio 2, n. 34).

“We see here an application of the Boethian omne namque esse ex forma est that he himself did not grasp. In the composite thing, its esse can be said to be constituted, as it were, by the principles of its essence (quasi constituitur per principia essentiae), but chiefly by its form” (Boethius and Aquinas, 216).

Footnote: In IV Metaphysic., lectio 2, n. 558. In Boetii De trinitate, q. 5, a. 3, c.: “Secunda operatio respicit ipsum esse rei, quod quidem resultat ex congregatione principiorum rei in compositis, vel ipsam simplicem naturam rei concomitatur ut in substantiis simplicibus.”

“Thomas waives the difference between Plato and Aristotle on the Ideas, and cites them as examples. Nor is this unusual. Thomas will always agree with Aristotle’s rejection of the Forms or Ideas when taken to be the separate counterpart of common names of sensible things. But he will eagerly embrace the Forms as ways of grasping simple things” (Boethius and Aquinas, 216).

Footnote: On this see the remarkable prologue to St. Thomas’s commentary on De divinis nominibus of Pseudo-Dionysius. “Haec igitur Platonicorum ratio fidei non consonat nec veritati, quantum ad hoc quod continet de speciebus naturalibus separatis, sed quantum ad id quod dicebant de primo rerum Principio, verissima est eorum opinio et fidei Christianae consona.” Text as edited by Ceslai Pera, O.P., Marietti, 1950.

“That which is truly, through and through, simple will not be a subsistent form of being, but subsistent existence itself. And here we must say that there can be only one truly simple thing, and this is God” (Boethius and Aquinas, 216).

Footnote: “Id autem erit solum vere simplex, quod non participat esse, non quidem inhaerens, sed subsistens. Hoc autem non potest esse nisi unum; quia si ipsum esse nihil aliud habet admixtum praeter id quod est esse, ut dictum est, impossibile est id quod est ipsum esse, multiplicari per aliquid diversificans: et quia nihil aliud praeter se habet admixtum, consequens est quod nullius accidentis sit susceptivum. Hoc autem simplex unum et sublime est ipse Deus” (lectio 2, n. 35).

“In the case of De hebdomadibus, the text of Boethius seems to be making an obvious point—it is explicitly said to be a per se nota one—when it states that diversum est esse et id quod est” (Boethius and Aquinas, 250).

Both Boethius and Thomas are careful to establish the meanings of forma and esse with reference to physical substances. Unless this is first done, the extension of the diversity [of esse and quod est] to subsistent forms cannot coherently be carried off. More importantly, this background is needed to grasp the significance of Thomas’s description of God as Ipsum esse subsistens(Boethius and Aquinas, 252).

(The observation that the axiom diversum est esse et id quod est is a self-evident axiom is presented by McInerny in several other of his works. See his “Boethius and Saint Thomas Aquinas,” Rivista di Filosofia Neo-Scolastica 66 [1974]: 219-245; Being and Predication: Thomistic interpretations [Washington, D.C.: The Catholic University of America Press, 1986], 55;  “Saint Thomas on De hebdomadibus,” in Being and Goodness: The Concept of the Good in Metaphysics and Philosophical Theology, ed. Scott MacDonald [Ithaca, Cornell University Press, 1991], 75-76; Praeambula Fidei: Thomism and the God of the Philsophers [Washington, D.C.: The Catholic University of America Press, 2006], 303; and “Saint Thomas Aquinas,” in The Stanford Encyclopedia of Philosophy, ed. Edward N. Zalta, 30 September 2009.)

(Regarding the philosophical nature of Boethius’s De hebdomadibus, see also Jan A. Aertsen, “What is First and Most Fundamental? The Beginnings of Transcendental Philosophy,” in Was ist Philosophie im Mittelalter? ed. Jan A. Aertsen and Andreas Speer [Berlin: Walter de Gruyter GmbH & Co., 1998], 179.)


Monday, April 6, 2015


0400: Commentary on actus essendi

Text no. 13



Commentary on 

Expositio in librum Boetii De hebdomadibuslecture 2

(Quotations from the writings of J. A. AertsenPart II)  


In his commentary on Boethius’s De hebdomadibus Aquinas uses the expression actus essendi twice, in lecture 2: “Sicut possumus dicere de eo quod currit sive de currente quod currat inquantum subiicitur cursui et participat ipsum, ita possumus dicere quod ens sive id quod est sit inquantum participat actum essendi. (…) Sed id quod est, accepta essendi forma, scilicet suscipiendo ipsum actum essendi, est, atque consistit, idest in seipso subsistit; non enim ens dicitur proprie et per se nisi de substantia cuius est subsistere.

Since the publication of Cornelio Fabro’s works on participation (in 1939 and 1960), the In librum Boetii De hebdomadibus expositio has received considerable attention. Thus, before offering my own commentary on the context surrounding the text where Aquinas explicitly employs the expression actus essendi in his In De hebdomadibus, I shall first review some of the comments that have been offered by other authors in the relatively recent period since Fabro’s books.


C.2. Jan A. Aertsen  

From the passages from Jan A. Aertsen’s Medieval Philosophy and the Transcendentals: The Case of Thomas Aquinas reported below we take the following points:

(a) According to Aertsen, a clue for the clarification of Aquinas’s understanding of esse is provided by Thomas’s commentary on the proposition diversum est esse et id quod est.

(b) Aertsen indicates that the shift in terminology from forma essendi to actus essendi is noteworthy. The consideration that guides Aquinas’s thought is this: esse signifies actualitas, and it signifies it after the manner of the verb. Like other verbs, the verb esse brings to expression some activity, but Aquinas sees a fundamental difference between esse and the other verbs. Other verbs, like currere signify accidental actions. Esse, however, is not a secondary act, but the primary act.

(c) For Aquinas, the focal meaning of the term esse is the intrinsic metaphysical principle of actus essendi, which is immediately accessible to the human intellect in all the material extramental subsisting things of nature.

Here are excerpts from Jan A. Aertsen’s Medieval Philosophy and the Transcendentals: The Case of Thomas Aquinas (Leiden: E. J. Brill, 1996):

“In the basic text on the transcendentals, it is only in De veritate 1.1 that Thomas indicates summarily the ratio of ‘being:’ ens sumitur ab actu essendi. Something is denominated ‘being’ from the act of being. In the same text, in answer to an objection that cites an axiom from Boethius’s De hebdomadibus, ‘to be (esse) and what is (quod est) are diverse,’ the ratio of being is explicitly formulated. Thomas’s explanation of the axiom is that the act of being (esse) is distinguished from that to which that act belongs. ‘The ratio entis, however, is derived from the act of being, not from that to which the act of being belongs’” (Medieval Philosophy and the Transcendentals, 185).

Footnote: De verit. 1.1 ad 3 (in contr.)

“One of Thomas’s relatively rare ‘ego’ statements concerns his understanding of being. ‘What I call esse is the most perfect of all.’ His argument is that act is always more perfect than potentiality. Now, any form, such as humanity or fire, is understood to exist actually only in virtue of the fact that it is held to be. ‘It is evident, therefore, that what I call esse is the actuality of all acts, and for this reason it is the perfection of all perfections’” (Medieval Philosophy and the Transcendentals, 185).

Footnote: De pot. 7.2 ad 9: “hoc quod dico esse est inter omnia perfectissimum: quod ex hoc patet quia actus est semper perfectior potentia. Quaelibet autem forma signata non intelligitur in actu nisi per hoc quod esse ponitur. Nam humanitas vel igneitas potest considerari ut in potentia materiae existens, vel ut in virtute agentis, aut etiam ut in intellectu: sed hoc quod habet esse, efficitur actu existens. Unde patet quod hoc quod dico esse est actualitas omnium actuum, et propter hoc est perfectio omnium perfectionum.”

“The distinctive feature of Thomas’s understanding of being is the notion of ‘actuality.’ In his own judgment he differs in this respect from Aristotle, who conceived ‘being’ as the quiddity of something” (Medieval Philosophy and the Transcendentals, 185-186).

Footnote: In III Sent., 8.5 ad 2: “Philosophus non accepit esse secundum quod dicitur actus entis (…) sed accipit esse pro quidditate vel ratione quam significat definitio.”

“It is also Thomas’s understanding of being as actuality that distinguishes his thought fundamentally from another metaphysical conception, which arose from ‘the second beginning of metaphysics,’ the scientia transcendens of Duns Scotus. (…) The difference between Thomas’s transcendental thought and Scotus’s apparently goes back to a different understanding of being, and it is therefore crucial to clarify the central moment of Thomas’s concept” (Medieval Philosophy and the Transcendentals, 186).

“A clue for this clarification is provided by Thomas’s commentary on the proposition just cited from Boethius’s De hebdomadibus. As we saw earlier (3.7.), Thomas reads this treatise from the perspective of the transcendentals (maxime communia). Boethius’s ‘common conceptions of the soul,’ or axioms, have a determinate order, since they are related successively to ‘being,’ ‘one’ and ‘good.’ The second axiom is ‘To be and what is are diverse’ (diversum est esse, et id quod est)” (Medieval Philosophy and the Transcendentals, 186).

Footnote: Cf. R. McInerny, Boethius and Aquinas, Washington, D.C. 1990, pp. 161-98 for a survey of the interpretations of this axiom.

Before continuing with Aertsen's remarks on p. 186, here is what Aertsen writes in section 3.7.:

“Thomas continues in lectio 6 [of the In IV Metaphysicorum] with a personal excursus that, as usual, is introduced by the phrase sciendum est and that goes far beyond the littera of the text. What is striking in this exposition is that he gives a foundation to Aristotle’s anhypotheton, the principle of contradiction. He shows that it is dependent (dependet) on something else. When one reconstructs how Thomas comes to this conclusion, his argument proves to be a synthesis of several insights from the philosophical tradition” (Medieval Philosophy and the Transcendentals, 148).

“The first moment in the foundation of the principle of contradiction concerns the notion of a proposition that is self-evident (per se notum) and is inspired by Boethius’s writing De hebdomadibus. As we saw in the first chapter, the reception of this treatise played an important role in the beginning of the doctrine of the transcendentals because of its central theme, the relation between being and goodness. Thomas is not only interested in this issue, but also in a more general aspect of Boethius’s work, which bears upon the basis of transcendental thought as such” (Medieval Philosophy and the Transcendentals, 148).

“Boethius starts De hebdomadibus with an explanation of his method. He will proceed ‘as is usually done in mathematics.’ According to the model of Euclid’s Elements he will put forward a number of axioms, which he calls termini or regulae, on the basis of which the argument that follows will be worked out and the question of the goodness of things will be solved. He lists nine axioms of which the first provides a general description of the cognitive status of these axioms: ‘a common conception of the soul (communis animi conceptio) is a statement that anyone approves as soon as he hears it.’ These conceptions are distinguished by Boethius into two groups: some are known to all human beings, others only to the wise” (Medieval Philosophy and the Transcendentals, 148).

Footnote: Boethius, De hebdomadibus (ed. Stewart e.a., pp. 38-40): Ut igitur in mathematica fieri solet ceterisque etiam disciplinis, praeposui terminos regulasque quibus cuncta quae sequuntur efficiam. (I) Communis animi conceptio est enuntiatio quam quisque probat auditam. Harum duplex modus est. Nam una ita communis est, ut omnium sit hominum (. . .) Alia vero est doctorum tantum, quae tamen ex talibus communis animi conceptionibus venit.”

“In the preceding, fifth, lectio Thomas had referred to this distinction of Boethius” (Medieval Philosophy and the Transcendentals, 148).

Footnote: In IV Metaph., lect. 5, 595: “Unde Boethius dicit in libro De hebdomadibus, quod quaedam sunt per se nota sapientibus quae non sunt per se nota omnibus.” Thomas refers to this distinction at several places in his work. See especially S.th. I, 2.1.

“Thomas wrote a commentary on De hebdomadibus, which was a quite unusual text to comment on in the thirteenth century. In the first lectio, he explains Boethius’s terminology. Boethius calls the axioms termini, ‘because in these principles the analysis (resolutio) of all demonstrations comes to an end.’ By this explanation Thomas indicates that the axiomatic method actually entails the way of resolution. Boethius calls the axioms regulae, because through them someone is led to knowledge of the subsequent conclusions” (Medieval Philosophy and the Transcendentals, 148-149).

Footnote: In De hebdom., lect. 1.

“But Thomas is primarily interested in the phrase ‘common conception of the soul’” (Medieval Philosophy and the Transcendentals, 149).

“He interprets it as a proposition that is self-evident, because the predicate is included in the essence of the subject. He argues that Boethius’s distinction concerning common conceptions is connected with the terms of which such propositions are composed. Universally self-evident are propositions that use terms understood by all human beings. That which falls in every intellect is the most general (maxime communia). Terms of this kind are ‘being,’ ‘one’ and ‘good’” (Medieval Philosophy and the Transcendentals, 149).

Footnote: Ibid., lect. 2: “ille propositiones sunt maxime note que utuntur terminis quos omnes intelligunt; ea autem que in intellectu omnium cadunt sunt maxime communia, que sunt ens, unum et bonum.”

“These three notions are named by Thomas, since through them he is able to give an order to Boethius’s axioms, which remains fully implicit in De hebdomadibus itself. Thomas reads Boethius’s methodological introduction from the perspective of the transcendentals. The first moment in his foundation of the principle of contradiction is a continuing resolution: the reduction of self-evident propositions to the terms of which they are composed. The first principles of demonstration are composed of the transcendental notions” (Medieval Philosophy and the Transcendentals, 149).

“The second moment is the idea that there is a certain order in the apprehension of the most common notions. That which the intellect first conceives is ‘being.’ This is the reason, Thomas argues in his commentary on the Posterior Analytics, that all sciences take the universally self-evident proposition ‘it is impossible for a thing to be and not to be at the same time’ from metaphysics, since it is the office of this science to consider being and that which belongs to it” (Medieval Philosophy and the Transcendentals, 149).

Footnote: In I Post. Anal., lect. 5, 50.

“Thomas always refers to Avicenna for the thesis that being is the first conception of the intellect. This thesis was widely invoked, not only by Aquinas but also by other thinkers of the thirteenth and fourteenth century. An explanation of its influence may be that Avicenna bases the firstness of being on the parallelism with the structure of demonstrative science. Just as propositions must be reduced to a first evident principle, so too the conceptions of the human intellect. The beginning of Thomas’s account in De veritate 1. 1 is completely determined by the idea of this parallelism taken from Avicenna (cf. 2.2.)” (Medieval Philosophy and the Transcendentals, 149-150).

“In his commentary on Metaphysics IV, however, Thomas goes a step further in comparison with both Avicenna and his own account in De veritate 1, 1. There is not only a parallel between the order of conceptual knowledge and that of demonstration, but that which is the principle in the order of conceptions is the foundation of that which is first in the order of demonstration. The point of departure of his argument is the Aristotelian view that the intellect has two operations. The first is the operation by which the intellect knows ‘what something is,’ the other the operation by which it composes and divides, that is, by which it forms affirmative and negative statements. In both operations there is something first. In the first operation the first that the intellect conceives is ‘being’—nothing can be conceived by the mind unless ‘being’ be understood. The principle ‘it is impossible for a thing to be and not to be at the same time’ depends on the understanding of this first. For that reason this principle is by nature the first in the second operation of the intellect” (Medieval Philosophy and the Transcendentals, 150).

Footnote: In IV Metaph., lect. 6, 605: “Ad huius autem evidentiam sciendum est, quod, cum duplex sit operatio intellectus: una, qua cognoscit quod quid est (…); alia, qua componit et dividit: in utroque est aliquod primum: in prima quidem operatione est aliquod primum, quod cadit in conceptione intellectus, scilicet hoc quod dico ens; nec aliquid hac operatione potest mente concipi, nisi intelligatur ens. Et quia hoc principium, impossibile est esse et non esse simul, dependet ex intellectu entis (…), ideo hoc etiam principium est naturaliter primum in secunda operatione intellectus, scilicet componentis et dividentis.”

“The new moment in Thomas’s commentary is that he grounds the first principle of demonstration on what is absolutely first, i.e., ‘being.’ He gives what we might call a ‘transcendental’ foundation to the principle of contradiction. The term fundatur is used by Thomas himself in Summa theologiae I-II, 94.2. This text represents an exemplary synthesis of the different moments we have analyzed thus far. Thomas first mentions Boethius’s distinction concerning that which is per se notum. Next he establishes an order in the most common notions. Here Avicenna’s view that ‘being’ is the first known gets its place. Finally Thomas presents the relation of foundation he had worked out in his commentary on Metaphysics IV: ‘In man’s apprehension of the most common notions there is a certain order. For that which first falls under apprehension is “being,” the understanding of which is included in all things whatsoever somebody apprehends. For this reason the first indemonstrable principle, “it is impossible to affirm and deny simultaneously,” is based (fundatur) on the notions of “being” and “non-being”’” (Medieval Philosophy and the Transcendentals, 150-151).

Footnote: S.th. I-II, 94.2. For the analysis of this text, see sect. 7.8.

In section 7.8 Aertsen writes:

“Both theoretical and practical reason proceed from self-evident first principles. Thomas proceeds to discuss the nature of these propositions and introduces a distinction between them that is derived from Boethius’s De hebdomadibus. Some propositions are self-evident only to the learned, who understand the meaning of the terms of such propositions. Other axioms are universally self-evident, because the terms of these propositions are known to all” (Medieval Philosophy and the Transcendentals, 327-328).

Footnote: S.th. I-II, 94.2: “sicut dicit Boetius, in libro De hebdomad., quaedam sunt dignitates vel propositiones per se notae communiter omnibus: et huiusmodi sunt illae propositiones quarum termini sunt omnibus noti (…). Quaedam vero propositiones sunt per se notae solis sapientibus, qui terminos propositionum intelligunt quid significent.”

“Thus Thomas enters the domain of the transcendentals by reducing the universally self-evident principles to the first intelligibles” (Medieval Philosophy and the Transcendentals, 328).

“The next part of the argument is focused on the order among the transcendentals. That order is related to the apprehension of the most common notions. That which the intellect first conceives is ‘being,’ for its understanding is included in all things whatsoever a human being apprehends. The remarkable thing in Thomas’s exposition is that he establishes a relation of foundation between the first conception of the human intellect, ‘being,’ and the first principle of theoretical reason. The principle of contradiction, i.e., that ‘the same thing cannot be affirmed and denied at the same time,’ is founded on the notions of ‘being’ and ‘non-being’” (Medieval Philosophy and the Transcendentals, 328).

Footnote: S.th. I-II, 94.2: “In his autem quae in apprehensione omnium cadunt, quidam ordo invenitur. Nam illud quod primo cadit in apprehensione, est ens, cuius intellectus includitur in omnibus quaecumque quis apprehendit. Et ideo primum principium indemonstrabile est quod non est simul affirmare et negare, quod fundatur supra rationem entis et non entis: et super hoc principio omnia alia fundantur, ut dicitur in IV Metaphys.

“Thomas advances here an idea that he elaborates in his commentary on book IV of the Metaphysics. As we have seen (3.7.: ‘Metaphysics and the first principle of demonstration’), he goes beyond Aristotle by giving a transcendental foundation to the ‘axiom of all axioms’ that Aristotle called the anhypotheton of human thought” (Medieval Philosophy and the Transcendentals, 328).

“(…) the first principle of theoretical reason is reduced to the first transcendental, being” (Medieval Philosophy and the Transcendentals, 330).

Back to p. 186:

“Thomas begins his commentary [on Boethius’s De hebdomadibus] with an important observation. The diversity affirmed by the axiom [diversum est esse et id quod est] is semantical in nature; it does not refer to things but to the meanings (rationes seu intentiones) of the terms esse and ens. Only later, in connection with the axioms bearing on the ‘one,’ will Boethius apply the diversity to things. But what is meant by the diversity of rationes? Thomas compares the difference between the meanings of esse and what is or being (ens) with the difference between the meanings of the infinitive ‘to run’ (currere) and of the subject ‘that runs’ (currens). The diversity of meanings is a difference in the modes of signifying. Esse and ‘to run’ signify in abstracto, but ens and ‘runner’ in concreto” (Medieval Philosophy and the Transcendentals, 186-187).

Footnote: In De hebdom. lect. 2.

“The semantical diversity between esse and ens is, on Thomas’s reading, clarified by Boethius’s elucidation of the second axiom: ‘To be itself is not yet, but what is, when it receives the form of being, is and subsists’ (Ipsum enim esse nondum est, at vero quod est, accepta essendi forma, est atque consistit). ‘To be’ does not signify something that is, it abstracts from the subject of being (subiectum essendi) and signifies the act as such, indeterminately. Therefore, we cannot say that ‘to be’ ‘is,’ any more than we can say that ‘to run’ runs. But ens ‘is,’ insofar as it participates in the act of being. The shift in terminology in the commentary is noteworthy: Boethius says ‘receives the form of being,’ which Thomas glosses as ‘participates in the act of being.’ Ens, like ‘runner,’ signifies the act as concretized in a subject which has it. Now, Boethius states not only that ens ‘is,’ but also that it ‘subsists.’ Does this claim not apply, however, only to substances? Thomas reminds us that ‘being’ is an analogous term whose focal meaning is ‘substance,’ which is per se and in the proper sense” (Medieval Philosophy and the Transcendentals, 187).

Footnote: Ibid., lect. 2.

“This commentary sheds lights on Thomas’s understanding of being. Being (ens), while the most general, is said ‘concretely,’ it signifies the concretion of subject and act” (Medieval Philosophy and the Transcendentals, 187).

Footnote: Ibid., lect. 2: “Set id quod est siue ens, quamuis sit communissimum, tamen concretiue dicitur.”

“This explains why the ratio of being has a certain complexity; it means ‘what has being.’ In view of the diversity of meaning between esse and ens it is not irrelevant that in Thomas’s philosophy the first conception of the intellect is ‘being’ (ens), not esse. In comparative studies of the views of Thomas and Heidegger on being, there is a tendency to ignore this difference” (Medieval Philosophy and the Transcendentals, 187).

Footnote: See, e.g., J. B. Lotz, “Aletheia und Orthotes, Versuch  einer Deutung im Lichte der Scholastik,” in: Philosophisches Jahrbuch 68 (1959), p. 265.

“But the first known is the concrete ‘what is,’ not ‘to be’” (Medieval Philosophy and the Transcendentals, 187).

“That the first conception of the intellect concerns a concretum is also clear from Thomas’s discussion of the type of predication in which a concrete term is said of an abstract one (praedicatio concreti de abstracto). The historical roots of this discussion lie in a question from the Summa de bono of Philip the Chancellor dealing with the predication ‘goodness is good’” (Medieval Philosophy and the Transcendentals, 187-188).

Footnote: Summa de bono, q. 9 (ed. Wicki, p. 30): “De hac predicatione: bonitas est bona.”

“Is such a predication correct? It does not seem to be, for we can say neither that ‘whiteness is white’ nor ‘warmth is warm.’ However, Thomas argues, we must distinguish here between special forms and general forms (formae generales). In the case of the latter it is possible to predicate a concrete form of an abstract one. We can say ‘essence is being,’ ‘goodness is good,’ or ‘whiteness is being.’ The reason is that being is what first falls upon the intellect. Everything we apprehend we apprehend, therefore, as ‘being,’ and consequently as ‘one,’ ‘true’ or ‘good,’ since these terms are convertible with ‘being.’ That is why ‘being’ and the other three concreta can be predicated of abstracta. This does not hold, however, for the special forms, for these are not transcendental, they ‘do not follow inseparately (concomitantur inseparabiliter) the ratio of being.’ We do not apprehend everything under the aspect of ‘white,’ so that we are not compelled to say ‘whiteness is white’” (Medieval Philosophy and the Transcendentals, 188).

Footnote: De verit., 21.4 ad 4: “aliter se habet in formis generalibus, et aliter in formis specialibus. In formis enim specialibus non recipitur praedicatio concreti de abstracto, ut dicatur Albedo est alba, vel Calor est calidus (…) Sed in formis generalibus huiusmodi praedicatio recipitur: dicimus enim quod essentia est ens, et bonitas bona, et unitas una, et sic de aliis. Cuius ratio est quia illud quod primo cadit in apprehensione intellectus est ens, unde oportet quod cuicumque apprehenso per intellectum intellectus attribuat hoc quod est ens. Et ideo cum apprehendit essentiam alicuius entis, dicit illam essentiam esse ens; et similiter unamquamque formam generalem vel specialem, ut: bonitas est ens, albedo est ens, et sic de aliis. Et quia quaedam sunt quae concomitantur rationem entis inseparabiliter, ut unum, bonum et huiusmodi, oportet quod haec de quolibet apprehenso praedicentur eadem ratione qua ens; unde dicimus essentia est una et bona, et similiter dicimus unitas est una et bona, et ita de bonitate et albedine et qualibet forma generali vel speciali. Sed album, quia est speciale, non concomitatur inseparabiliter rationem entis; unde potest apprehendi forma albedinis sine eo quod attribuatur ei esse album, unde non cogimur dicere Albedo est alba;” De pot.,9.7 ad 8 and 9 (in contr.): “de quolibet eorum praedicetur, ens, et alia tria concreta;” S.th. I, 55.4 ad 1.

Esse is said in abstracto. It signifies the act of being as such; accordingly, Thomas also uses the abstract term actualitas for it. We noticed the shift from ‘form’ to ‘act’ of being in his commentary, but Thomas’s exposition does not provide any further clue for understanding his notion of ‘actuality.’ What is striking, however, is his semantic approach to Boethius’s axioms: his explanation is based on the different modes of signifying of concrete subject and infinitive. Given this approach, it is appropriate to take into consideration another text dealing the verb ‘to be.’ It is found in Thomas’s commentary on Perihermeneias I, 3” (Medieval Philosophy and the Transcendentals, 188-189).

Footnote: Cf. A. Zimmermann, “Ipsum enim [est] nihil est’ (Aristoteles, Periherm. I, c. 3). Thomas von Aquin über die Bedeutung der Kopula,” in : A. Zimmermann (ed.), Der Begriff der Repraesentatio in Mittelalter (Miscellanea Mediaevalia 8), Berlin and New York 1971, pp. 282-95.

“At the end of chapter three, Aristotle argues that a verb does not yet signify whether a thing is or is not, for the verb is not a sign of the being or non-being of a thing. He points out that even the verb ‘to be’ is not different in this respect from other verbs. A text which has caused great difficulty for its commentators states: “That is even not the case when you say ‘is’ alone, for it is by itself ‘nothing,’ but it consignifies some composition which cannot be understood without the compound elements (16b 22-25)’” (Medieval Philosophy and the Transcendentals, 189).

Footnote: The Latin text on which Thomas comments reads: “Nec si hoc ipsum ‘est’ purum dixeris: ipse quidem nichil est. Consignificat autem quandam compositionem quam sine compositis non est intelligere.” See In I Perih., p. 25.

“Thomas observes in his commentary that the Greek text has the word ‘being’ (to on) in place of ‘is’ here, and he comments on both readings” (Medieval Philosophy and the Transcendentals, 189).

“His [Thomas’s] explanation of the first reading (‘being’) was presented in the previous section where we opposed the contention of ‘Existential Thomism’ that the concept of ens entails a judgment” (Medieval Philosophy and the Transcendentals, 189).

In the previous section, on p. 180, Aertsen writes:

“The starting point of the resolutio in De veritate 1.1 is the investigation into what something is (quid est). The ultimate term for this reduction is ‘being,’ which is no genus. The name ‘being’ signifies ‘what is’ but does not signify a mode of being determined by the genera” (Medieval Philosophy and the Transcendentals, 180).

Footnote: This generalness and indeterminateness is one of the reasons Thomas advances for his view that “being” (Qui est) is the most proper name of God. S.th. I.13.11: “Quolibet enim alio nomine determinatur aliquis modus substantiae rei: sed hoc nomen Qui est nullum modum essendi determinat, sed se habet indeterminate ad omnes.”  See sect. 9.1.

“The reason that ‘being’ is the first conception of the intellect is that everything is knowable insofar as it is in act. When something is apprehended as ens, it is grasped that it has being. Ens names a thing from the formality of its act of being: it primarily signifies ‘what is.’ Thus the concept of being is indeed complex, but not in the way a proposition is complex. The concept of being does not signify the judgment ‘something exists,’ the kind of composition which is susceptible of truth or falsity. Thomas explicitly denies this kind of composition in the concept of being. In his commentary on a passage in Perihermeneias that deals with the expression ‘is,’ he writes about the signification of ‘being:’ ‘Ens does not principally signify that composition which is implied in the expression ‘is’ (est), but it ‘consignifies’ it, insofar as it signifies a thing having being (rem habentem esse). Therefore, such a ‘consignification’ does not suffice for truth or falsity—since the composition in which truth and falsity consist cannot be understood except insofar as it connects the extremes of the composition’” (Medieval Philosophy and the Transcendentals, 180).

Footnote: In I Perih., lect. 5, 20.

Our conclusion is that the thesis of ‘Existential Thomism,’ that ‘being’ is attained only in judgment, the second operation of the intellect, is incorrect. ‘Being’ is attained in simple apprehension. The concept principally signifies ‘what has being,’ ‘what is,’ a phrase that does not entail a judgment” (Medieval Philosophy and the Transcendentals, 180).

“We turn now to his [Thomas’s] explanation of the second reading” (Medieval Philosophy and the Transcendentals, 189).

Thomas is intrigued by the fact that Aristotle speaks of the ‘consignification’ of ‘is,’ which consists in its function as copula. Yet ‘consignification’ presupposes a primary meaning. What is the principal signification of ‘is,’ on which the ‘consignification’ depends? His answer is: ‘[The verb “is”] signifies primarily that which falls upon the intellect in the manner of actuality in the absolute sense—since “is,” absolutely speaking, signifies to be in act, and therefore it signifies after the manner of the verb. However, the actuality which the verb “is” principally signifies is generally the actuality of every form or act, whether it be substantial or accidental. Thus, when we want to signify any form or act actually to be in some subject, we do so by means of the verb “is” (…); and for this reason the verb “is” consequently signifies a composition’” (Medieval Philosophy and the Transcendentals, 189).

Footnote: In I Perih., lect. 5: “significat enim primo illud quod cadit in intellectu per modum actualitatis absolute; nam ‘est’ simpliciter dictum significat esse actu, et ideo significat per modum uerbi. Quia uero actualitas quam principaliter significat hoc uerbum ‘est,’ est communiter actualitas omnis forme uel actus, substantialis uel accidentalis, inde est quod, cum uolumus significare quamcunque formam uel actum actualiter inesse alicui subiecto, significamus illud per hoc uerbum “est” (…); et ideo ex consequenti hoc uerbum est significat compositionem.”

This text is central for grasping Thomas’s understanding of being. The primary significance of ‘is,’ he states, is ‘to be in act,’ and he draws from this the conclusion that ‘therefore it signifies after the manner of the verb.’ This conclusion points to the considerations guiding Thomas’s line of thought” (Medieval Philosophy and the Transcendentals, 190).

“The verb is the subject-matter of chapter three of Perihermeneias. Proper to the verb is to signify something after the manner of an action or passion” (Medieval Philosophy and the Transcendentals, 190).

Footnote: Ibid., lect. 5: “proprium autem uerbi est, ut significet actionem;” “est enim proprium uerbi significare aliquid per modum actionis uel passionis.”

“The verb ‘to be’ must therefore also bring to expression some activity. But Thomas sees a fundamental difference between ‘to be’ and the other verbs. Other verbs, like ‘to run,’ signify accidental actions. ‘Esse,’ however, is not a secondary act, but the primary” (Medieval Philosophy and the Transcendentals, 190).

Footnote: Cf. S.th. I, 54.1: “Actio enim est proprie actualitas virtutis; sicut esse est actualitas substantiae vel essentiae.”

“It is the prerequisite condition of every act, the actuality of every form or act. Esse is the actuality of all things, ‘since it is related to everything as act. Nothing has actuality except insofar as it is” (Medieval Philosophy and the Transcendentals, 190).

Footnote: S.th. I, 4.1 ad 3: ipsum esse est perfectissimum omnium: comparatur enim ad omnia ut actus. Nihil enim habet actualitatem, nisi inquantum est: unde ipsum esse est actualitas omnium rerum.”

“From the principal signification of ‘is,’ its copulative function must be understood. Because actuality is always the actuality of a form, we use ‘is’ in joining subject and predicate to signify that a form actually is in a subject” (Medieval Philosophy and the Transcendentals, 190).

“The ontological meaning of the diversity between ens and esse comes to the fore in the continuation of Thomas’s commentary on Boethius’s De hebdomadibus. Whereas, on his reading, the second axiom expresses the semantic differences, the diversity is ‘applied to things’ in the axioms concerning ‘the one.’ These axioms are: (VII) ‘In a simple thing its esse and what is are one;’ (VIII) ‘In every composite, to be and what is are different’” (Medieval Philosophy and the Transcendentals, 190).

Footnote: In De hebdom. lect. 2: “Hic ostendit quomodo applicetur ad res.” For an analysis of these axioms, see R. McInerny, Boethius and Aquinas, pp. 211-16.

“The first principle of things is marked by identity and simplicity. All other things are composed in the sense that there is a real difference between their ‘to-be’ and ‘what is.’ Even a subsisting form, although not composed of matter and form, does not possess complete simplicity. It is not its being (esse), but has it, because each form is determinative (determinativa) of being. The form determines a thing to a specific mode of being, and is not being in general (ipsum esse commune)” (Medieval Philosophy and the Transcendentals, 190-191).

Footnote: Ibid., lect. 2.

“We encountered these formulations earlier in Thomas’s sketch of the history of philosophy (3.8.). The second stage of the history is marked by the ‘formal’ way of thought, but Thomas stresses that this phase cannot be the last. In the second phase being is considered under a particular aspect, because the form determines a thing to a special mode of being. Only in the third phase, in which being is considered as being, is each thing ‘resolved into that which is and its being (esse).’ Thomas formulates the metaphysical resolution of things in the Boethian terminology of the real diversity” (Medieval Philosophy and the Transcendentals, 191).

Here is a relevant segment of what Aertsen wrote in section 3.8.

“[Thomas’s] works furnish sufficient evidence that the transcendental way of thought is not merely an abstract possibility for him. On the contrary, the transcendental view turns out to be the perspective from which Thomas understands the evolution of philosophy. This reading is best supported by the sketch of the historical progress of philosophy that he presents in five writings: De potentia 3. 5; Summa contra Gentiles II, 37; In VIII Phyisicae, lect. 2; De substantiis separatis c. 9; and Summa theologiae I, 44.2. We take the last text as point of departure, employing the other texts to complete our analysis” (Medieval Philosophy and the Transcendentals, 151).

“Thomas’s sketch of the history of philosophy confirms the conclusion of the first sections of this chapter: the very conception of metaphysics has itself become transcendental” (Medieval Philosophy and the Transcendentals, 155).

“One of the most remarkable features of Summa theologiae I, 44.2 is that the idea of creation appears as a result and the completion of the internal development of human thought. The argument does not appeal to any text from Scripture. Thomas’s philosophical reflection about the origin of reality is a more adequate example of Gilson’s concept of ‘Christian philosophy’ than the ‘metaphysics of Exodus’ (cf. sect. 0.1). The Christian idea of creation is interpreted from the perspective of transcendental thought as a causality that extends to being in general. ‘Something is called created because it is a being (ens), not because it is this being (hoc ens)’” (Medieval Philosophy and the Transcendentals, 156).

Footnote: S.th. I, 45.4 ad 1.

“In Thomas’s account of the history of philosophy we recognize the two forms of resolutio, the resolutions secundum rationem and secundum rem, which he had presented as the methods of metaphysics (3. 4.)” (Medieval Philosophy and the Transcendentals, 156).

In section 3.4, Aertsen writes:

“The distinction secundum rationem / secundum rem is not the opposition between ‘logical’ and ‘natural’ analysis. [Logical analysis here refers to the method of the analysis of concepts; natural analysis refers to the analysis through which the composed is resolved into the more simple.] Rather, it concerns that towards which the discursive analysis of reason is directed. This can be another thing, when something is reduced to its extrinsic causes, but this is not the only possible terminus. In resolution secundum rationem, a thing is reduced to its intrinsic forms or principles” (Medieval Philosophy and the Transcendentals, 134).

“The two forms of resolution correspond to the two forms of commonness Thomas distinguished in q. 5 art. 4 of his commentary [on Boethius’s De trinitate]: commonness by predication and commonness by causality. This correspondence might be confusing at first sight, since both resolutions proceed by the analysis of causes. Yet it makes sense to relate resolution secundum rem to causal commonness and resolution secundum rationem to commonness by predication. The former resolution is an analysis of extrinsic causes and a reduction to the most universal cause. In q. 5 art. 4, Thomas had worked out only causal commonness by tracing the hierarchy of causes. Resolution secundum rationem is an analysis of intrinsic causes and a reduction to the most general form. The end-term of this process is ‘being,’ that is, that which is predicated of all things” (Medieval Philosophy and the Transcendentals, 134).

Footnote: For ‘being’ as cause, see S.th. I, 5, 2 ad 2: “Ens autem non importat habitudinem causae nisi formalis tantum, [vel inhaerentis vel exemplaris, cuius causalitas non se extendit nisi ad ea quae sunt in actu.]”

“That resolution secundum rationem concerns commonness by predication does not compromise its metaphysical character, for the analysis is carried out to the ultimate form, by which something is being. There exists an intrinsic connection between this resolution and the resolution secundum rem, for the latter reduction is the reduction to the cause of being as being” (Medieval Philosophy and the Transcendentals, 134-135).

“The method of resolution is central to Thomas’s account of the transcendentals in De veritate 1. 1. In this basic text he pursues a resolution of knowledge in which the concepts of the intellect are reduced to being as the first conception. The understanding of being is the beginning and basis of human rational activity. The cognitive priority of being indicates an essential difference between the metaphysical resolutions secundum rationem and secundum rem, for the terminus of the latter resolution, God, is not the first known but the final end of the human desire for knowledge. The difference between the two resolutions marks the distinction made by Thomas between the subject of metaphysics and the causes of this subject” (Medieval Philosophy and the Transcendentals, 135).

Back to the argument on p. 156:

“On the one hand, human reason proceeds from the particular forms to the most universal ones. The ultimate term of this resolution is the consideration of being. In the parallel text in De susbtantiis separatis, c. 9, Thomas describes this process in terms of a type of resolutio that we have not yet encountered. It is the resolution of being into its internal principles: in the last phase of the evolution of philosophy each thing is resolved into ‘that which is’ and its ‘being’ (esse). On the other hand, a causal reduction occurs that terminates in the universal cause of being. Thomas’s account shows the inner connection between the two resolutions, for the fact that the causality of the first cause is universal can only be understood, when the proper intelligibility of being-as-being is considered” (Medieval Philosophy and the Transcendentals, 156).

And now, back to the argument on p. 191:

“Things receive their esse from the universal cause of being; they are created. From a transcendental perspective, creation is the causality that extends to being in general. From this view-point Thomas interprets the fourth proposition from De causis, ‘the first of created things is being (esse).’ The thesis does not mean by esse a subsisting thing, but the proper aspect of the object of creation. ‘For something is called created because it is a being (ens), not because it is this being (hoc ens)’” (Medieval Philosophy and the Transcendentals, 191).

Footnote: S.th. I, 45.4 ad 1.

“The view that the esse of things has an external origin was common to Thomas and Avicenna. But the Arabic philosopher draws a conclusion from the createdness of being, which profoundly affects his understanding of being. Because ‘all that something has, not through itself, but from another, is outside (praeter) its essence,” he concludes that the esse of every created thing is outside its essence” (Medieval Philosophy and the Transcendentals, 191).

Footnote: De verit. 8.8: “Omne autem quod aliquid non habet a seipso sed ab altero, est ei praeter essentiam suam; et per hunc modum probat Avicenna quod esse cuiuslibet rei praeter primum ens est aliquid praeter essentiam ipsius quia omnia ab alio esse habent.”

“Being is added to a thing’s quiddity in the manner of an accident, it is a ‘concomitant’ of a thing” (Medieval Philosophy and the Transcendentals, 191).

Footnote: Avicenna, Liber de philosophia prima I, 5 (ed. Van Riet, p. 36): “Intellectus de ente comitabitur illam.” For Avicenna’s doctrine, see G. Verbeke, “Introduction doctrinale,” in: ibid., pp. 62*-80*. Cf. L. De Raeymaeker, “L’etre selon Avicenne et selon S. Thomas d’Aquin,” in: Avicenna Commemoration Volume, Calcutta 1956, pp. 119-31.

“Thomas too recognizes a real diversity in things; he even accepts in some texts, e.g., in Quodlibet II, 2.1, that ‘being’ (esse) is an accident, when ‘accident’ is taken in the wide sense of ‘whatever is outside (praeter) a thing’s essence.’ But he denies that being is an accident in the proper sense of the word, that is, a categorial accident. Being is called ‘accident,’ not because it belongs to the genus accident but by virtue of a certain similarity to it: neither forms part of the essence of a thing” (Medieval Philosophy and the Transcendentals, 191-192).

Footnote: De pot. 5.4 ad 3: “esse non dicitur accidens quod sit in genere accidentis, si loquamur de esse substantiae (est enim actus essentiae), sed per quamdam similitudinem: quia non est pars essentiae, sicut nec accidens.” Cf. Quodl. XII, 5.1. See J. Owens, “The Accidental and Essential Character of Being in the Doctrine of St. Thomas Aquinas,” in: J. R. Catan (ed.), St. Thomas Aquinas on the Existence of God, Collected Papers of Joseph Owens, Albany N.Y. 1980, pp. 52-96.

“For Thomas there is a profound difference between the two senses of accident, to which he points in the same Quodlibet. Being (esse) is an accident, not as though related accidentally to a substance, but as the ‘actuality’ of any substance” (Medieval Philosophy and the Transcendentals, 192).

Footnote: Quodl. II, 2.1 ad 2: “esse est accidens, non quasi per accidens se habens, sed quasi actualitas cuiuslibet substantiae.”

“Here a new aspect of the notion of ‘actuality’ comes to the fore. Thomas conceives being in a way that is self-consciously critical of Avicenna’s understanding of being” (Medieval Philosophy and the Transcendentals, 192).

“Thomas’s view of the composition of essence and esse in every created thing has two features. The first corresponds to Avicenna’s view: in a composite thing, being cannot be caused by its essential principles, for no thing is the essential cause of its own being. It is caused by something else (causatum ab alio). The second feature marks the difference from Avicenna: being is the actuality of every form” (Medieval Philosophy and the Transcendentals, 192).

Footnote: See for these two features S.th. I, 3.4: “Oportet ergo quod illud cuius esse est aliud ab essentia sua, habeat esse causatum ab alio (…). Oportet igitur quod ipsum esse comparetur ad essentiam quae est aliud ab ipso, sicut actus ad potentiam.”

“In other words, it [esse] is the act of ‘that which is,’ the inner principle of the concrete ens(Medieval Philosophy and the Transcendentals, 192).