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Monday, February 23, 2009

0059: The Text from Quaestiones Quodlibetales 9, 4, 1, c

Entry 0059: Actus Essendi - The Text from Quaestiones Quodlibetales 9, 4, 1, c

Sed quia substantia Angeli non est suum esse -- hoc enim soli Deo competit, cui esse debetur ex seipso, et non ab alio --; invenimus in Angelo et substantiam sive quidditatem eius, quae subsistit, et esse eius, quo subsistit, quo scilicet actu essendi dicitur esse, sicut actu currendi dicimur currere. Et sic dicimus Angelum esse compositum ex quo est et quod est, vel secundum verbum Boetii ex esse et quod est. Et quia ipsa substantia Angeli in se considerata est in potentia ad esse, cum habeat esse ab alio, et ipsum esse sit actus; ideo est in eo compositio actus et potentiae; et sic posset in eo concedi materia et forma, si omnis actus debeat dici forma, et omnis potentia materia. Sed hoc non competit in proposito; quia esse non est actus qui sit pars essentiae, sicut forma; ipsa quidditas Angeli vel substantia est per se subsistens, quod materiae non competit.

Monday, February 16, 2009

0058: Actus Essendi: Commentary on De Potentia , 7, 2, ad 1

Entry 0058: Actus Essendi - Commentary on De Potentia 7, 2, ad 1

Although the text begins with an explicit reference to ens as the present active participle of esse, no mention is made of the fact that ens is more than just a verbal adjective. The stress is placed rather on the fact that esse has two well-defined meanings.

The text from De Potentia unequivocally differentiates esse in its restricted meaning of actus essendi from esse in its wider meaning of “the truth of a proposition.”

With the example of “blindness,” the text sends us back to the conception of “existence,” which I previously described as the consequence of an actual “state of affairs.”

A person lacking sight is a real person, an actual “state of affairs.” And “blindness” connotes the absence of a quality.

Thus, when we say that 'blindness exists,' 'caecitas est,' we are simply translating our knowledge of the fact of existence into a true statement. The statement is true because we affirm the existence of “that which is.”

This aspect of the verb est does not refer to the metaphysical principle of actus essendi; it refers to an actual “state of affairs,” to the fact of existing.

In its wider meaning, esse refers to “the truth of a proposition” which may simply state something about the absence of being.

Monday, February 9, 2009

0057: Actus Essendi: The Text from De Potentia , 7, 2, ad 1

Entry 0057: - Actus Essendi: the Text from De Potentia 7, 2, ad 1

Here is another text from the "Series of Texts in which Aquinas Explicitly uses the Expression Actus Essendi:"

Ens et esse dicitur dupliciter, ut patet V Metaph. Quandoque enim significat essentiam rei, sive actum essendi; quandoque vero significat veritatem propositionis, etiam in his quae esse non habent: sicut dicimus quod caecitas est, quia verum est hominem esse caecum. Cum ergo dicat Damascenus, quod esse Dei est nobis manifestum, accipitur esse Dei secundo modo, et non primo. Primo enim modo est idem esse Dei quod est substantia: et sicut eius substantia est ignota, ita et esse. Secundo autem modo scimus quoniam Deus est, quoniam hanc propositionem in intellectu nostro concipimus ex effectibus ipsius.


Ens and esse may be taken in two ways (Metaph. X, 13, 14). Sometimes they signify the essence of a thing and the ‘act of being,’ and sometimes they denote the truth of a proposition even in things that have no being: thus we say that ‘blindness is’ because it is true that a man is blind. Accordingly when Damascene says that God’s existence is evident to us, the esse of God is taken in the second sense and not the first. For in the first sense God's esse is the same as his essence, and as his essence is unknown so also is his esse. In the second sense we know that ‘God exists,’ because we conceive this proposition in our mind from his effects.”

Monday, February 2, 2009

0056: Actus Essendi: Commentary on Summa Theologiae I, 3, 4, ad 2

Entry 0056: - Actus Essendi: Commentary on Summa Theologiae I, 3, 4, ad 2

Reading the works of Aquinas one finds that he used the Latin verb esse to signify in more than one way. In his Summa Theologiae (I, 3, 4, ad 2,) he is clear on this. Thus he writes,

It must be said that esse applies to a thing in two ways. In one way, it means the act of being, actus essendi. In another way, it means the composition of a proposition effected by the mind in joining a predicate to a subject. Taking esse in the first sense, we cannot understand God’s esse nor His essence; but only in the second sense we can understand the esse of God. For we know that this proposition which we form about God when we say ‘God is,’ is true; and this we know from His effects.

In the first sense God’s esse is His actus essendi; in the second sense, esse applied to God means ‘God exists.’

By means of demonstration and reasoning one can prove the ‘existence’ of a thing without having to have recourse to the sense experience of an existing exemplifying individual. The grasping of the ‘act of being’ of a particular thing is indeed the strongest evidence that the thing exists, but the knowledge of the ‘existence’ of a particular thing and the grasping of its ‘act of being’ are entirely different issues. The grasping of the ‘act of being’ requires direct and immediate contact with individual, real sensible things. On the other hand, to answer the question of whether or not a thing exists, one does not have to interact directly with existing sensible things.

See also Entry 01-0048 and Stephen L. Brock, "Thomas Aquinas and 'What Actually Exists,'" Wisdom Apprentice, P.A. Kwasniewski, Ed., The Catholic University of America Press, Washington, D.C., 2007, pp 13-39.