Is the substance of creatures 'potentiality'?


I’m still thinking about the pantheistic/monist conception of reality versus ours and the problem of “what really is our own substance?”

The only duality is being and non-being/existence and nothingness, which is not really duality.

So God exists fully (Actus Purus), but we also exist but are not Actus Purus. But we are not nothingness either, we actually do exist and have a real substance. So what are we?

Is it wrong/heretical to conceive of a second duality besides being and non-being? The duality of Actuality and potentiality? So we can say creatures are ‘all that is in potentiality’ and God is the Actus Purus?

So a third “option” between nothingness and the fullness of being…a second kind of “substance” we can call potentiality? But it does not seem potentiality represents a real substance. Yet it seems, on the other hand, the perfect realm of creatures: i.e substances that don’t have to BE…

Tagging, as usual, @RealisticCatholic and @Wesrock.



You really exist. You are a being, since you are a unity that is in its own right, distinct from that thing over there, and that thing over there. All of these have existence in common. But they are different.

All things, different as they are, exist: But they participate in existence and are not the fullness of existence. God is Pure Act of Existence itself, while all creatures are a combo of essence and existence — where, in a way, essence is not an extra thing added but the factor that limits existence to a certain manner of be-ing.

You don’t have pantheism here because the Ultimate Reality is the fullness of being, with no potential to be this or that. But other beings do exist, and this is as obvious as the fact that this unity over here is distinct from this unity over there. Existence they share in common, but they are not the fullness of it. They are just as distinct from each other but also from God.

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Thank you, @RealisticCatholic, for your response as always. In light of the pm I’ve sent you (which I request you not to reproduce here) what would you say is the answer to those who posit that an Actus Purus cannot act, as it is fully actual? That the ultimate reality would lack “momentum” “thought” “intentionality” if it does not also have potential? How does it create us?

(If you don’t mind, I would also be interested to read your thoughts, @Ghosty1981)



Ah, I think my hunch of a second duality was not far off in fact! I found this in the encyclopedia.



I presume you zre attempting to use the philosophic vocab of Aristotle/Aquinas?
If so it would seem you are self taught as you do not seem to have a harmonious overview of how all these jargon words mesh together as a cohsrent whole.
There are far too many misunderstandings to correct on a forum…I think you would get a lot out of a Catholkc Phil course 101 at a uni near you.

One comment…essence and existence seem to be the co principles you are looking for. Pot/Act are not substances but principles of change. Every created substance is both in potency and act on a continuum whose limits are determined by its essence (its nature).



Are you saying God being pure act is not referring to God’s substance? As I understand it from St. Thomas, Actus Purus is just another term for “I AM” that God revealed and that we know to be the divine substance shared between the three members of the Trinity. So I don’t understand what point you were trying to make to be honest.



All creatures have a composition of potentiality but not only of potentiality or they would only be potentially existing. Their other principle is actuality by which they actually exist. So, the primordial principles of all creatures is a composition of actuality and potentiality. St Thomas said that act and potency divide being and every kind of being and so the first of the 24 Thomistic Theses is stated:

Potency and Act so divide being that whatsoever exists either is a Pure Act, or is necessarily composed of Potency and Act, as to its primordial and intrinsic principles.

God is pure act without any potentiality whatsoever while everything else that exists is a composition of potency and act and in various ways.

From Rubee:
So God exists fully (Actus Purus), but we also exist but are not Actus Purus. But we are not nothingness either, we actually do exist and have a real substance. So what are we?

Both God and creatures have actual being. This is what the principle ‘act’ means, to be actually existing. Potentiality in itself is potential being not actual being or actually existing. So, God is pure act, pure actuality, Being or existence itself. Creatures are a composition of act and potency but their being, actuality or existence is not being or existence itself. Our being or existence is created and caused by God, it is a created participation in being or existence. And so our existence is not univocally the same as God’s existence nor is it entirely equivocal but analogical. This is known as the analogy of being. There is a certain likeness and proportion of our existence or being to God’s existence yet also some difference, indeed, an infinite difference but not entirely different such as non-being is to being. God has being in a more eminent way than creatures do, in fact, God is Being itself.

Insofar as those who might posit that Pure Act cannot act, as it is fully actual, this doesn’t make any sense. How can that which is purely actual not act? A thing can only act insofar as it is actual. Potentiality doesn’t act, it is the correlative of actuality. God is wholly and purely actual, in act eternally. For example, God is never potentially knowing or understanding but always actually knowing and understanding. An intellect that is potentially knowing is not actually knowing.



They are saying, @Richca, that it is already actualized so it’s static. It cannot move, it’s complete. How can it create? They say. That entails a move from the potential to create to the reality of creating, therefore there was potential: Thats the argument. In other words, they believe that if you take away God’s desire for self-actualization, you must be left with a God that cannot act/desire anything. i.e No momentum.

Oh! And another is: God has always been actuality and potentiality

And thanks for replying!



Of course to me, God’s inability to want anything for himself (i.e. self-actualization) means God’s motive for everything is always Love. True disinterested Love. Agape. I.e God cannot “gain” anything from any activity whatsoever. But how to tell that to people who don’t already buy my premises?



Again, this doesn’t make any sense. A thing can only act insofar as it is actual, something actually existing. There is actual being and potential being. Potential being is not actually existing and what is not actually existing cannot act. What is potential can only be brought to act by what is in act or actually existing. In other words, potentiality cannot raise itself to act. Potentiality is not actuality.

The very word ‘act’ can be used as both a noun (something stable or static like, the essence of a thing) and a verb which is an action word (dynamic). Even as a noun though, the first meaning (from Websters Collegiate Dictionary) of the word ‘act’ has reference to the doing of something, an action of some sort. In reference to God as pure act who is without composition of any kind but who is an utterly simple being, ‘act’ carries both the meaning of the noun and verb at one and the same time.

Again, what is in act is actually existing, an actual being. Existing is a verb, an action word (dynamic) and it is synonymous with the english verb ‘be’ (philosophically and in latin this is not entirely accurate, to be and to exist do not actually carry the same meaning which is why St Thomas always uses the latin verb esse, to be, in reference to ‘existence’). For if we say ‘what is’, we think ‘what exists’. When Moses asked God what he should tell the Israelites who sent him, God said ‘I Am who Am’, go tell the Israelites He Who Is has sent me to you’. To be, to exist are verbs which are dynamic and so in St Thomas’ metaphysics ‘existence’ or rather the ‘act-of-being’ is that which actualizes everything and God is the ‘act-of-being’ itself. In other words, God is wholly dynamic which is what pure act means. As I said previously, we can use the word ‘act’ as a noun too in reference to God such as an actual being, something actually existing. But it points us right back to the verb, to be or to exist. In God, noun and verb are one and the same thing as it were.

Movement or change is an imperfect act, it is a composition of act and potency. Aristotle defined motion or change as ‘the act of a being in potency insofar as it is in potency’. God is not imperfect but possesses the fullness of being. There is nothing for him to change into or acquire more being as it were. He is Being itself and possesses it in its totality. Similarly, essential whiteness cannot change into more whiteness.



I think you still don’t get their contention. Their idea is: why would he need to do anything he wasn’t already eternally doing, e.g. create?



You mean like creating from eternity?

To create one needs to be in the act of creating. God is pure act, he is already in act to create whenever he wills to create. His will is already in act from all eternity. Something in act doesn’t need to move from potentiality to actuality.



They are saying, without potentiality, why would God ever change anything he was doing, i.e do something new. To them the fact that God is able to do things he wasnt doing before is proof he has potentiality since to them that constitutes a change.



Whatever God is doing now in time or creation He has willed to do so from all eternity in one eternal act of his will. Any change involves time, a before and after. For something becomes or is now what it wasn’t before. There is no before and after in God for he is eternal and so neither was there a change in his eternal will when he created the universe. For a will to change means that it is willing something now that it wasn’t willing before but God willed to create the universe from all eternity at that time he had willed to do so from all eternity.



Every created substance is both in potency and act.



The act of creation and God are same within your system of belief.



My system? How come? God does not create by nature, does he? Creation is an act of God’s arbitrary freedom, unlike, for example, the two divine processions that give us the Blessed Trinity.



Being is good. Therefore God is act of creation. He cannot do otherwise.



Nope! God does not have to create.



Ah, but he is eternally creating. There was no before that.


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