Help with some Aquinas?

I’m just reading through and I don’t understand this one part from the Summa:

" “To be” can mean either of two things. It may mean the act of essence, or it may mean the composition of a proposition effected by the mind in joining a predicate to a subject. Taking “to be” in the first sense, we cannot understand God’s existence nor His essence; but only in the second sense. We know that this proposition which we form about God when we say “God is,” is true; and this we know from His effects"

So what is Aquinas saying here? Obviously “God is” is not just empty word play and at the same time it is not an “act of essence” (existence?). But I thought that this question (whether God’s essence was His existence) was about existence? So then what else are we talking about? Is Aquinas touching upon the distinction between apriori and a posteriori knowledge?

I am by no means a Thomist scholar, but I’ll offer you my thoughts for now until someone more learned comes along (at leat it will bump the thread for you :wink: ):

First, it is nearly impossible to explain what I understand by this passage in clear English without distorting the meaning, but I’ll give it a go, apologies for the non-technical terms.

Do you speak Spanish? The distinction seems to me to be somewhat like the verbs ser and estar. If you don’t speak Spanish, of course, this is of no use, so I’ll move on.

In the first sense, I think Thomas is saying that ‘to be’ is a statement of what we are, in essence, by our nature. So we can understand the phrase ‘That is a horse’, ‘I am [a human]’, ‘here is a flower’ and comprehend what it meant by the terms horse, human or flower. But the same cannot be said of God: we can say ‘God is’, but not the entirety (or even the major part) of what is meant by the term God.

However, in the second sense, we can understand something of God from his effects. So, although we can’t understand ‘God is.’, we can partially understand ‘God is…’ e.g. God is creator, God is truth, God is love. These things do not portray the essence of what God is, but they show something of what he is. In the same way we can say ‘She is a lawyer’, ‘He is beautiful’ and these say something of what the person is but not the whole (clearly ‘he is beautiful’ is meant in a more qualified sense than ‘God is beauty’).

In my mind, it sort of correlates with a priori and a posteriori but I’ve never been comfortable tying it down to those terms as what we know about god is always both experiential and intuitive. It may just be that I only have a partial understanding of the terms (through Kant) and they apply perfectly here. I’ll leave someone else to expound on that!

The essence-existence distinction is one of Aquinas’ greatest loves. Since destructible objects exist, we must conclude that there is an indestructible object upon which they are all predicated.

He ceaselessly wrote about the difference between 1. the essence of a thing existing and 2. the thing itself actually existing. To say that a thing exists in essence is to say that its substance/deepest reality is a real possibility. You might say that the essence of a thing is its potentiality, and the existence is its actuality. The essence of tree-ness exists, even if there were no trees left on Earth for us to see. Plato might say that this essence comes from a Heavenly Tree, as it were, but Aquinas’ model (Aristotle) might say that this essence is something real in existence, which all trees have. Rocks (existence) have a rockiness (essence), but if a rock is destroyed it loses its rockiness; however, “rockiness” itself continues existing as a possibility.

Our doctor says that all things have an essence, even if there are no examples of that thing existing in the Universe. Imagine that all trees or all rocks in the whole Universe stopped existing. Would their treeish essence or rocky essence cease to be a possible, potential reality? No, I don’t think so! Some people say essence follows existence, i.e. a First Rock must exist before the Rocky Essence exists; however, God fashioned all essences in His perfect Mind before any physical universe was created. :slight_smile:

Aquinas uses this point to talk about God. Since all things have an essence in eternity, but not all things exist necessarily (as a foundation of space and time), there must be something that exists whose very essence is to exist. Rocks’ existence is not immortal; the actuality of trees can be muted and destroyed; say, by fire. Thomas says that there must be a singular being whose purpose/substance/essence consists solely in Existing, so it could not be un-existent. Some things may have essence, yet not exist in reality, but God’s very essence IS simply to exist, and His existence is His essence. “God is His own Existence”, while all else relies on His self-existing essence. He is the “foundation stone” upon which all building bricks must be laid, because the building bricks of this Universe can be destroyed.

Unicorns do not exist in actuality, but in potentiality. The unicorny essence, therefore, exists only by virtue of fairy-tales, and no unicorns have come into existence. God might chose to make them into existence, but it doesn’t change the fact that they aren’t real. :wink: It’s about necessity and reality and foundations.

That is to say, expressing that “God is” is to express something which we can never know in the sense that we can only grasp essences and existences distinctly but not together? And yet we know “God is” is true? Or maybe “God is” means to us, “God is at least as real as the rock in front of me, but of the idea of the supra-real I only have metaphors to understand Him and not a fixed knowledge of His own essence.”

Thanks for this I think that it is going down the right track.

I would say you pretty much have it.

We form the proposition “God is” by knowing certain effects. What we really know, then, is “these things are inadequate to explain themselves, and therefore there must be some mode of being beyond our ken which explains them.” What that mode of being is in its total knowability is beyond comprehension. We can only know it secondarily, so to speak.

I like GloriousOrder’s response.

I think of it like this:
It may mean the act of essence,

or it may mean the composition of a proposition effected by the mind in joining a predicate to a subject.

Taking “to be” in the first sense, we cannot understand God’s existence nor His essence; but only in the second sense. We know that this proposition which we form about God when we say “God is,” is true; and this we know from His effects"

God’s existence in the first sense can’t be contained in any human mind or concept, and neither could it be a mere part of a complex propositional whole. In propositions, the individual being of the subject and/or predicate must be less than the whole proposition’s being (or else a part would be greater than the whole). So the 2nd mode of being is, I suppose, the same as propositional unity, seen by distinguishing [Socrates + whiteness] (which only has the being of an abstract set or mereological sum) from ‘Socrates is white.’

As essentially a complex mode of being, i.e., as entailing parts, this second being is not on par with the absolute simplicity of God. Our minds are attributing a complex unity when they assert that “God is,” because our own concept of God includes an array of effects/properties/concepts. ‘God’ includes omnipotence, omnipresence, omnibenevolence, omniscience, etc.; ‘God is’ exists as the affirmed unity of all these terms. It’s true analogically, pointing up to where our minds can’t go.

Warning* – henceforth, I’ll mostly be rambling out my personal thoughts…]

Now, to me it seems that we should perhaps distinguish ‘to be’ (potential being, sort of) from ‘to exist’ (actual being). If Aquinas is speaking about existence, he’s on point. However, it seems to me that a third sort of being would “exist”, namely, the being of abstract sets, concepts, properties, subjects, etc., which would be like the “matter” of propositions. Although, I’m not so sure these do have legitimate being, at least not any more than “prime matter” would (i.e., mere potency may not have any being).

I think the profundity in Thomism may be in his refusal to permit “mere being” (being, essence) as somehow “more fundamental” than “actual being” (existence). He apparently did this by uniting them in a divinely simple Being/Existence (Ipsum Esse Subsistens). So then one question would remain: how do we know simpler concepts such as “propositional matter” w/“mere being”? The answers could be intriguing, but I think they’d have to maintain that man’s conception of “mere being” is actually less fundamental than his notion of actual being, since we always see existence first, before we abstract “mere being” out of it. But then our very concept of ‘mere being’ would exist in our mental activity…*

[More rambling]

Maybe the first mode of being is being simpliciter, whereas the second mode is being as the willful act of an intellect (and the intellect itself reflects/has the primary being? or it only has it to the extent intellect & will are united, i.e., the extent of its substanitality?/spirituality?). So the second mode is in a way complex, being a unity of intellect and will. To any being whose will and intellect aren’t essentially identical, the result of their unity would be secondary being (or, I guess, even if the intellect and will were identical).

Then all of created being is the secondary being, because it’s all like God’s one act of willfully uniting things in His intellect. As such, the things are secondary, a lesser reflection of the primary being (b/c the cause is always greater than its effect). I think we would therefore have to assert, also, that God’s act of creation was not done by uniting pre-existing things/essences (mere possibilia), but that they were all created along with the act. So is possibility a creation of God? Perhaps God’s act of creation was His own “abstraction” of mere possibility, away from pure actuality, in His mind (creating both heaven and earth – but earth as initially just a “dark, formless void” over which the Spirit blew). Then His “letting there be light” was “illumination” of possibility, which reflects it intelligibly, or, makes it true. Truth, as He saw, is good, so He willed its “division” (double-sight, re-illumination)), etc. Each division of possible being makes a new finite degree of being, or essence, which may then be united w/primary being…

I think a lot of this would come down to the issue of whether God had to create or not. In what sense is God “free”?

Or maybe I’m just drowning in abstract concepts and pure, speculative theory.

This is an important question. Anselm’s ontological argument (that than which no greater can be thought must exist) assumes that “God with creation” is no greater than “God without creation” - God did not need to create. There does not have to be a world (Aristotle would not have been able to understand this). And I am not just talking about a world if you happen to believe in multiverses … there does not have to any world or any infinite number of worlds … there does not have to be anything … other than God of course … agape love is the conclusion we have to draw from all this contingency …


Think of ‘essence’ as what a thing is, and ‘existence’ as how a thing is. What a human is, primarily and properly: his essence: is rational animal. Adult (child, male, female) is how a human is but not primarily and properly. What a thing is, is substance to it. How a thing is, is accidental (incidental) to it. Humans are conceptual, thinking, reasonable (essence, essentiality): removing it removes human-ness. (A dead human is said to be ‘human’ analogously.) Humans are tall or short (accidental, incidental): removing it does not remove human-ness. Loss of ‘life’ does remove a human, but, ‘life’ is not a part of the human primarily and properly, for it is common to all creatures. What is essential to essence is that which is distinctive of a subject and that subject alone: for example, in humans. Many things can exist as can exist as ‘liquid’, but, only water can exist as water. “Animal” can be said of other things (a bird, a horse); and, “rational” can said of other things (computers, in a way). But, “rational animal” is only be said of humans.

God, on the other hand, is pure essence. What’s more, his essence is understood to entail existence. As humans, we can understand what it is to be in ‘existence’, but, we cannot but barely understand ‘essence as existence’. We merely juxtapose the words. Without that ability, the ability to conflate two (or more) words, meanings, we could not know God in any manner, other than as an Olympian, i.e., an being from Mt. Olympus. Mixing words permits us to know God, analogically. The terms we use (the terms’ usage) to define, that is, describe, God we take from nature: we could say, we anthropomorphize. But, his essence is infinite light years beyond that.

A priori means from before. A posteriori means from after. A priori is often conflated with “from intuition.” A posteriori is often conflated with “from experience,” although current usage is “from observation by way of examination or experimentation.” A priori has referents to dialectical induction. We can know something – and, know that it is – from an a priori dialectic which results in a valid induction, or just know it from that which many believe was placed in our minds from the moment we existed.

“To be” means, from our everyday, usual usage, to be-in-existence. In that sense, be can be said of even invisible things, as well. An ‘idea’, a ‘scene remembered’, the ‘future prefect’, are said (common usage) to be, even if solitary and fleeting. The “act of essence” means to abstract (speciate, define). Or, it can mean: the incarnation of essence. It is human-ness wrapped in skin; or, it is an abstraction wrapped in (an invisible) covering.

God bless,

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