Actus purus

In scholastic philosophy, Actus Purus (Latin for 'Pure Actuality' / 'Pure Act') is the absolute perfection of God.

Overview

Created beings have potentiality that is not actuality, imperfections as well as perfection. Only God is simultaneously all that he can be, infinitely real and infinitely perfect: 'I Am that I Am' (Exodus 3:14). His attributes or his operations are really identical with his essence, and his essence necessitates his existence. (Contrast this understanding with the Essence–Energies distinction in Eastern Christianity, particularly Palamite, theology).

Charles Albert Dubray, as accepted by Charles George Herbermann, stated that in created beings,

the state of potentiality precedes that of actuality; before being realized, a perfection must be capable of realization. But, absolutely speaking, actuality precedes potentiality. For in order to change, a thing must be acted upon, or actualized; change and potentiality presuppose, therefore, a being which is in actu. This actuality, if mixed with potentiality, presupposes another actuality, and so on, until we reach the actus purus.

According to Thomas Aquinas, a thing which requires completion by another is said to be in potency to that other: realization of potency is called actuality. The universe is conceived of as a series of things arranged in an ascending order, or potency and act at once crowned and created by God, who alone is pure act. God is changeless because change means passage from potency to act, and so he is without beginning and end, since these demand change. Matter and form are necessary to the understanding of change, for change requires the union of that which becomes and that which it becomes. Matter is the first, and form the second. All physical things are composed of matter and form. The difference between a thing as form or character and the actual existence of it is denoted by the terms essence and being (or existence). It is only in God that there is no distinction between the two. Both pairs – matter and form, essence and being – are special cases of potency and act. They are also modes: modes do not add anything to the idea of being, but are ways of making explicit what is implicit in it.

Common Being and Being as Pure Act

According to Thomas Aquinas, God can also be defined as the act of all acts, the perfection of all perfections and the perfect Being. This Being is also called being in the strong sense or intensive Being (Esse ut actus, or Actus essendi) to distinguish it from being in the weak sense or common being (esse commune) of all created entities. The intensive Being includes every possible determination, thus excludes any other addition, is the highest real perfection; the common being is the highest abstraction and the lowest perfection, universal and totally indeterminate, indifferent to any addition (which neither excludes nor even includes).

The common being is the object of metaphysics, which studies being as being in the universal manner.

According to Fr Battista Mondin, the common being is also analogical, like the intensive Being. Otherwise, if the common being were to be preached unambiguously, all entities would be reduced to a single entity. God cannot coincide with the common being because it would be reduced to a mere abstraction existing in the human mind alone.

While the common being is immanent like all the entities which it is abstracted from, instead the intensive Being, who is God Himself, is transcendent. Both of them are transcendental in respect of the nine Aristotelian categories.

A univocal common being is the object of the philosophies of Parmenides and Plato, as well as of Scotus, Suárez, and Wolff. An immanent Being is the object of the philosophies of Plotinus, Spinoza, Hegel and Heidegger.

The most perfect Being (or Esse ipsum subsistens, Being that subsists by itself and not in virtue of other-from-itself), is as strong and powerful, intelligent and free, noble and precious, profound and intimate to creatures, as nobody else can exist.

See also

• Actual idealism
• Actus essendi
• Hyperuranion
• Thomism
• Avicennism

From the 1913 Catholic Encyclopedia

Actus Purus, a term employed in scholastic philosophy to express the absolute perfection of God. In all finite beings we find actuality and potentiality, perfection and imperfection. Primary matter, which is the basis of material substance, is a pure potentiality. Moreover, change necessarily supposes a potential element, for it is a transition from a state.of potentiality to a state of actuality; and material things undergo manifold changes in substance, quantity, quality, place, activity, etc. Angels, since they are pure spirits, are subject to none of the changes that depend on the material principle. Nevertheless, there is in them imperfection and potentiality. Their existence is contingent. Their actions are successive, and are distinct from the faculty of acting. The fact that all things have in themselves some potentiality warrants the conclusion that there must exist a being, God, from whom potentiality is wholly excluded, and who, therefore, is simply actuality and perfection, Actus Purus.

It is true that in the same being the state of potentiality precedes that of actuality; before being realized, a perfection must be capable of realization. But, absolutely speaking, actuality precedes potentiality. For in order to change, a thing must be acted upon, or actualized; change and potentiality presuppose, therefore, a being which is in actu. This actuality, if mixed with potentiality, presupposes another actuality, and so on, until we reach the Actus Purus. Thus the existence of movement (in scholastic terminology, motus, any change) points to the existence of a prime and immobile motor. Causality leads to the conception of God as the unproduced cause. Contingent beings require a necessary being. The limited perfection of creatures postulates the unlimited perfection of the Creator. The direction of various activities towards the realization of an order in the universe manifests a plan and a divine intelligence. When we endeavour to account ultimately for the series of phenomena in the world, it is necessary to place at the beginning of the series—if the series be conceived as finite in duration—or above the series—if it be conceived as eternal-a pure actuality without which no explanation is possible. Thus at one extreme of reality we find primary matter, a pure potentiality, without any specific perfection, and having, on this account, a certain infinity (of indetermination). It needs to be completed by a substantial form, but does not of itself, demand any one form rather than another. At the other extreme is God, pure actuality, wholly determined by the very fact that He is infinite in His perfection. Between these extremes are the realities of the world, with various degrees of potentiality and actuality.

So that God is not a becoming, as in some pantheistic systems, nor a being whose infinite potentiality is gradually unfolded or evolved. But He possesses at once all perfections. He is simultaneously all that He can be, infinitely real and infinitely perfect. What we conceive as His attributes or His operations, are really identical with His essence, and His essence includes essentially His existence. For all intelligences except His own, God is incomprehensible and indefinable. The nearest approach we can make to a definition is to call Him the Actus Purus. It is the name God gives to Himself: "I am who am", i.e., I am the fullness of being and of perfection.

Aristotle, esp. Metaphysics, Bk. XI (Berlin, ed. 1831); Physics, Bks. VII, VIII; St. Thomas, Comment. in lib. VII, VIII Physic, and in lib. XII Metaphysic. (XI of Berlin ed.); Summa theologica, esp. P. I. QQ. ii, iii, iv, etc., Contra Gent. L. I, c. xiii, xvi, etc.; Piat, Dieu et la nature d'après Aristotle in Revue neo-scholastique, VIII, 1901, p. 167 (reproduced in his book Aristotle, L, II, c., ii Paris, 1903); Watson, The Metaphysic of Aristotle, IV—The Divine Reason, in Philos. Rev. VII (1898), p. 341.