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Monday, March 16, 2009

0062: Actus Essendi: Commentary on In Metaphysicorum , 4, 2, No. 6

Entry 0062: Actus Essendi - Commentary on In Metaphysicorum, 4, 2, No. 6

Just as he did in De Veritate, 1, 1, c, in the present text, Aquinas once again clarifies his understanding of the transcendental notion of res (thing), a term which derives its content from the quiddity or essence of the thing.

The underlying principle of this doctrine is this. In the real world one cannot have the metaphysical principle of ‘essence’ in isolation from the metaphysical principle of actus essendi. One cannot have one without the other. In the real world essences exist with the actus essendi, and vice versa, the actus essendi always appears instantiated in an essence. It is for this reason that the term res (thing) expresses a transcendental notion; res stands for a universal mode of being that follows upon the fact of having an essence. Essences are found in every existing thing without exception.

It is this inherent unity of the two most fundamental metaphysical principles what allows Aquinas to provide a coherent metaphysical account of the transcendental ‘one’ and the charaterisctic ‘unity’ of a subsisting thing.

From the side of the actus essendi every existing thing is said to be ens and from the side of the essence every existing thing is said to be res. But it is from the internal inseparability of these two metaphysical principles that every existing thing is said to be unum. Unum is as well a transcedental notion; unum derives its content from the indivisibility of 'essence' and actus essendi.