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Monday, March 19, 2012

0217: The Sources that Led Aquinas to the Discovery of the Notion of Actus Essendi

Entry 0217: The Sources that Led Aquinas to the Discovery of the Notion of Actus Essendi

Professor John F. Wippel writes:

“As for Aquinas’s view that esse or the act of being is the act of all acts and the perfection of all perfections, I am aware of no explicit prior philosophical (or theological) source for this.

“It has been suggested by Gilson (and by others) that Thomas took this notion from Scripture at Exodus 3:14 where, according to the Latin Vulgate, God refers to himself as Ego sum qui sum.

“See Gilson, Introduction a la philosophie chretienne, c.3, pp. 45-58.

“For a similar view concerning the essence-existence distinction see Gilson’s Thomism: The Philosophy of Thomas Aquinas, trans. L. K. Shook and A. Maurer (Toronto, 2002), pp. 95-96.

“Note in particular: ‘Note well that for Thomas Aquinas the revelation of the identity of essence and existence in God was equivalent to a revelation of the distinction between essence and existence in creatures’ (p. 95).

“I would rather argue that it is precisely because Aquinas had already worked out philosophically his understanding of esse or the actus essendi as intrinsic actuality that he could then claim to recognize it in the text of Exodus.

“For instance, in SCG I, c. 22, which Gilson cites, Thomas first offers a series of philosophical arguments to prove that in God essence and esse are identical.

“Only at the end of the chapter does he refer to the text from Exodus for additional confirmation.

“And this is in accord with his usual practice in the first three books of SCG in which, as he writes in Bk I, c. 9, he intends to pursue by following the way of reason those things that faith professes and human reason can investigate about God.

“Editio Leonina manualis, p. 8: ‘… primum nitemur ad manifestationem illius veritatis quam fides profitetur et ratio investigat, inducentes rationes demonstrativas et probabiles, quarum quasdam ex libris philosophorum et Sanctorum collegimus …’

“As for philosophical sources, serious efforts have been made to find Aquinas’s source(s) for developing his notion of esse in one or other Neoplatonic author.

“Pseudo-Dionysius has been proposed as a likely source or influence, especially by Cornelio Fabro and more recently by Fran O’Rourke, among others.

“See F. O’Rourke, Pseudo-Dionysius and the Metaphysics of Aquinas (Leiden-New York-Cologne, 1992), pp. 180ff. See p. 181, n. 161, for references to others.

“One may begin with what is perhaps Thomas’s most comprehensive discussion of this in De Potentia, q. 7, a. 2, ad 9.

“He opens his reply with this remark: ‘That which I call esse is among all things the most perfect, which is evident from this fact that act is always more perfect than potency.’

“But, he continues, a given form is not understood to be in act except by reason of the fact that it is held to be.

“And in support he notes that a form such as humanity or fireness can be considered in four ways: (1) as existing in the potency of matter; or (2) as existing in the power of an agent; or (3) as in the intellect.

“But (4) by reason of the fact that it has esse, it is made existent in actuality.

“And so, in light of this evidence, Thomas concludes that what he calls esse (hoc quod dico esse) is the actuality of all acts and the perfection of all perfections.

“‘Hoc quod dico esse est inter omnia perfectissimum: quod ex hoc patet quia actus est semper perfectio 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’ (Marietti edition, p. 192).

“(This, I would note, is a purely philosophical approach, based on Thomas’s observation of the different ways in which form or essence can exist.)

“It must not be thought, Thomas continues, that to what he calls esse anything is added so as to determine it in the way act determines potency: ‘Therefore it is not determined by something else in the way potency is determined by act but rather as act is determined by potency.’

“And so this esse is distinguished from that esse insofar as it belongs to this or that nature.

“Ibid. Note specially: ‘Nec intelligendum est, quod ei quod dico esse, aliquid addatur quod sit eo formalius, ipsum determinans, sicut actus potentiam: esse enim quod huiusmodi est, est aliud secundum essentiam ab eo cui additur determinandum. … Unde non sic determinatur esse per aliud sicut potentia per actum, sed magis sicut actus per potentiam. … Et per hunc modum, hoc esse ab illo esse distinguitur, in quantum est talis vel talis naturae.’

“Finally, as O’Rourke has pointed out, Thomas gives us at least a clue as to one of his sources for his views on this by concluding his reply to this same 9th objection with a reference to Dionysius (presumably to c. 5 of the De divinis nominibus) to this effect that, while living beings are more excellent than (merely) existing beings, nonetheless esse is more excellent than vivere; for living things not only have life, but simultaneously with life they also have esse.

“‘Et per hoc dicit Dionysius quod licet viventia sint nobiliora quam existentia, tamen esse est nobilius quam vivere; viventia enim non tantum habent vitam, sed cum vita simul habent et esse’ (p. 192).

“For O’Rourke see pp. 180-81. Note his quotation there from Solignac, and also the texts he cites from Fabro.

“In his Participation et causalite Fabro suggests that one may distinguish three elements in accounting for Thomas’s understanding of esse as intensive act: (1) the concept of act which, while expanded upon and developed by Thomas, is Aristotelian in inspiration; (2) the notion of intensity of act which, suggests Fabro, is typically Platonic in terms of the Platonic notion of a perfectio separata; (3) the decisive aspect, missing both in Plato and in Aristotle, of the complete and total assimilation of esse to act.

“Fabro identifies two kinds of sources for this third aspect—one scriptural, i.e., Exodus 3:14, which we have already discussed, and the other philosophical, i.e., Neoplatonic speculation regarding being in sources such as Dionysius, the Liber de causis, Proclus, and Boethius.

“He comments that none of these Neoplatonic sources yet contains the Thomistic notion of esse as act, for the good reason that the Aristotelian understanding of act is lacking to them.

“Pp. 198-99. Note that Fabro connects point 2 (the Platonic notion of perfectio separata with a text from Aristotle’s Metaphysics II, c. 1 (993b 24), which Thomas cites in connection with his ‘Fourth Way’ in ST I, q. 2, a. 3.

“If one accepts the authenticity of Bk II, it seems to me that one should regard this text as a remaining trace of Platonism within Aristotle.

“He [Fabro] argues that among these sources the De divinis nominibus of Dionysius and the Liber de causis exercised the greatest influence on Thomas’s development of his new and revolutionary understanding of esse.

“He also remarks that both of these ultimately go back to one same source, Proclus.

“Pp. 222-23.

“As Fabro points out, in his Commentary on the De divinis nominibus Thomas sees Dionysius as correcting the Platonists on a key point.

“They posited separate things existing in themselves (forms or ideas) in order to account for individual composite entities which participate in these separate principles.

“And they distinguished those separate principles from the first principle which they called the Good per se and the One per se.

“According to Thomas, Dionysius agreed with them in also positing a separate life that exists per se, and a separate wisdom that exists per se, and a separate esse etc.

“But he disagreed with them in that he did not hold that these separate principles were diverse from one another, but united them with one supreme principle, or God.

“For this in Thomas see In De divinis nominibus V, n. 634, p. 235.

“See Fabro, Participation e causalite, pp. 224-25.

“Thomas finds Dionysius holding that the first existent, which is God, causes every thing that exists in any way whatsoever (n. 628).

“He also holds that all things therefore in some way come together in God (conveniunt in Deo) because, as Thomas explains, every form which is received in something is limited and rendered finite according to the capacity of that which receives it.

“Thus a given white body does not possess the whole of whiteness according to the total power (posse) of whiteness.

“But if there were a separate whiteness, nothing would be lacking to it of that which pertains to the power (virtus) of whiteness.

“But all things other than the First Being have a received and participated esse and therefore do not possess it according to the total power of being (virtus essendi).

“Only God, who is ipsum esse subsistens, possesses it according to its total virtus (n. 629).

“Fabro cites Aquinas’s justification for applying the name being (ens vel qui est) to God.

“If a cause is named from its effect, it is most fittingly named from its principal and most worthy effect.

“But among all other effects, esse itself is more primary and principal.

“Therefore God is fittingly named “being” (ens).

“See n. 633.

“Thomas continues by quoting Dionysius: ‘et ipsum per se esse est senius, (idest primum et dignius) eo quod est per se vitam esse et eo quod est per se sapientiam esse et eo quod est per se similitudinem divinam esse.’

“See Fabro, pp. 228-29.

“Fabro concludes that the principal source for the Thomistic notion of intensive esse is, therefore, Dionysius, although he goes on to explore this in the Liber de causis and in Thomas’s late Commentary on the same; but I will pass over that here.

“See Fabro, La participation et causalite, pp. 231-44.

“O’Rourke also heavily, even more heavily than Fabro, emphasizes the influence of Dionysius on Aquinas’s understanding of esse as intensive act.

“Moreover, he stresses much more the importance of the notion of virtus essendi in Thomas’s development of his own position.

“Op. cit., pp. 167-74.

“On p. 172 he cites two texts where Dionysius does use this expression, although they do not appear in C. V but in C. VIII, 1 (332, 334).

“We have just noted Aquinas’s reference to this in his Commentary on De divinis nominibus.

“And this is not the only context in which Thomas assigns a virtus essendi or a potestas essendi to esse taken as the act of being.

“One of the most striking, I think, is to be found in his argumentation for divine perfection in SCG I, c. 28.

“As will be recalled from our discussion above in Ch. V, there Thomas reasons that if there is something to which the total power of being (tota virtus essendi) pertains, no excellence among those that can belong to any thing can be lacking to it.

“But esse according to its total power (secundum totam essendi potestatem) belongs to that thing which is identical with its esse.

“Because God is identical with his esse, as was proved above (c. 22), adds Thomas, it follows that nothing of the power of being is lacking to him.

“See the first argument offered in c. 28. For the Latin see Ch. V above, n. 18.

“In brief, there do seem to be significant Neoplatonic influences on Aquinas’s identification of esse as intensive act.” [1]

[1] John F. Wippel, Metaphysical Themes in Thomas Aquinas II, (Washington, D.C.: The Catholic University of America Press, 2007), 281-284.