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Simplicity and Trinity, Friends or Foes?

An Introduction to Complementary and Misunderstood Doctrines

In elementary terms, how does the doctrine of simplicity relate to the doctrine of the sacred Trinity? The answer is, simplicity is provisional, among other things, for gaining insight into God himself as Trinity, Father, Son, Spirit. Simplicity is part of the prolegomena for trinitarian teaching, because simplicity is in the cement of any monotheism and so inherent to the stability of anything built upon the basic judgement which affirms merely that God is and nothing more (quia est et nihil amplius, Thomas Aquinas says). God is, and God is Trinity: inasmuch as simplicity is invoked in saying the first, so much is it involved in saying the second.

We must not say too much or too little on this point. We must be very precise. To say too much, takes theology as a servant of the church, inverts it, and makes it a crushing load too heavy to bear (Luke 11:46). To say too little, takes theology as a help for knowing and loving God more, divests it of this capacity, and makes it worthless for bringing people closer to God. Let us first remind ourselves of the basics of the doctrine of simplicity, before turning to consider how it is ancillary for confessing God as Father, Son, and Holy Spirit. We must not say too much or too little on this point. We must be very precise. Click To Tweet

A Primer on Simplicity

What the doctrine of the Trinity is, is roughly known; but what is the doctrine of simplicity? In theology proper, simplicity is a negative name we utter of God. The doctrine of simplicity in no way posits or affirms something of God. Confessing simplicity is nothing else but negating or denying composition of God. “Simplicity,” throughout theology proper, means nothing else but the judgment, God is not composite.

Broadly, the name “simplicity” signifies any judgment removing from God a real composition; more specifically, it signifies the final intellectual judgment that has removed from God the fundamental composition among creatures, that of “esse and essentia,” “being and essence.” This judgment is final, because when it is made, ipso facto all other ways of composition have already been removed in the same stroke. The expression of this judgment and thus the final dogmatic statement pronounced by the catholic church on the doctrine of simplicity was provided first in 1215 at Lateran IV, at least in any official way; the first theologian to expound this statement with significant profundity was Thomas Aquinas, who was born closely thereafter (1224/25).

Picking up the phrase given at Lateran IV, he says, “Deus omnino simplex est”: God is not composed in any way; or, in another place, pushing this even further, he says, It is not possible that God be composed in any way. Either of these can be and is reformulated and declared as the doctrine of simplicity, where we confess God is in every way simple. This reformulation is a means of shorthand. I point out again, this is not an affirmation; it is, as we call it in theology, periphrastic only for a negative judgment. It is of utmost importance to not mistake on this point, and it is no exaggeration to claim that many theologians have done so for hundreds of years and with devastating results. The doctrine of simplicity in no way maintains or pronounces something of God positively; the doctrine of simplicity only and solely removes something from our conception of him, namely, composition.

Let us unpack this.

Outside theology, there are many things that are and are said to be “simple,” for we look around the world and many times make a negation of some composition for various reasons; the use of this in theology is firstly determined by how we do this with us and among creatures. We say in the everyday, a problem is simple, denying it has many elements to untangle. We say in another locus of theology, angels are simple, denying bodily composition. We say in philosophy, forms are simple, and matter is simple. And there are many other things that are simple, just as God is simple, albeit God is not simple in one way only, but simple in every way (omnino simplex): God is not composite, with any type of composition.

There is one other critical point of difference to bear in mind when we confess God’s simplicity. This is to do with the fact that, to put it very roughly, some things are simple, because they are empty; other things are simple, because they are full. That is to say, we are brought to deny composition of some, because they are lacking in some mode, and we are brought to deny composition of some, because they are abounding in some mode. The way of putting this metaphysically, is some are simple with a foundation in the order of potency; others are simple with a foundation in the order of act. The simplicity of matter and that of form are examples: matter and form are opposed, and we are brought to deny composition of each for opposed reasons: one is empty, just as potency; the other is full, just as act. Note that in both cases, an affirmation grounds our immediate negative judgment of simplicity, and that affirmation posits something in the thing. This something, placed in the thing with an affirmative judgment, is called the “foundation” in the thing for our negation of composition, which makes our negation be true. For this reason, there are two possible reasons in a thing to consider when we are dealing with simplicity, and each of these foundations is diametrically opposed. There are thus two opposite kinds of simplicity, generated by whether the reason or foundation in the thing is through the mode of potency or through the mode of act.

One of the most frequent mistakes on the issue of simplicity is to suppose that something is simple for the reason opposite to the actual reason it is simple. This may seem abstruse, but consider as an illustration why we might be brought to deny something is a color: it could be, because it is white; or it could be, because it is black. White and black are in every way opposed, but each prompts us to negate color. Put into metaphysical terms, we negate composition either due to something under the concept of act, or due to something under the concept of potency — and either of these reasons, not simplicity itself, generates radically different descriptions and considerations about the thing which is said to be simple.

God’s simplicity is counterintuitive to many because they assume God is simple because he lacks, but the reason we say he is not composite is because he is full. Click To Tweet This is why the doctrine of God’s simplicity is so frequently counterintuitive to many: they are thinking of the opposed reason for simplicity, as though God were simple because he lacks, when the reason we say he is not composite, is because he is full. They are thinking of simplicity in the material order, where “composition” and “structure” actually imply something better, a perfection. I look at a single-cell organism, and say it is simple, whereas I look at a person, and a marvel at their complexity. Likewise I call someone a simpleton, and my intent is not flattering, whereas I say someone has a complex view on a matter, and I am advancing praise. All of these are to predicate simplicity, founded on emptiness. In no way do we predicate simplicity of God in that way. We are brought to deny composition of God, for the opposite reason: because of his perfection.

God is simple, because he is the plenitude of life and is possessed of all riches. In the case of God, what is affirmed, which immediately braces our negation of composition? What is the real foundation in him, to render our negation true? It is, “ipsum esse subsistens”: Pure Subsistent Being. This is sometimes called for short, “pure act” (actus purissimus), but specifically, it is esse, being, not in the wispy, insecure, accidental way in which being is found with us and among creatures, but in the dense, solid, essential way it is found in God himself.

Here is the reason we say God is simple (not composite): because God is, with being which is not incomplete, imperfect, in part, in potency, accidental, received, or as one who has, all of which is how it is with us and among creatures; no, this one is, with being which is complete, perfect, whole, actual, substantial, per se subsistent, as The One Who Is. He incorporates all perfections found disparate and distributed and scattered throughout creation, into a solid and higher synthesis. And given that this is the foundation which supports our negative judgment “simplicity,” when we say God is simple, this confession does not entail God has been carved away to a nub, or that we are thinking of him in terms of absence, poverty, or lack.

We are merely reflecting upon his perfection and especially the manner or way of his perfection, and the fact that everything among creatures, everything of good and even of all being, is already found in God in a unique and independent intensive density of goodness that just is God himself. He is, having beforehand all good and being in himself altogether and at once, in a substantial or essential way, as Dionysius says and the catholic church ceaselessly repeats (praehabens in se omnia simul in seipso modo eminentissimo). Just as pure light that emanates from a source is carved into an array of particularized colors, so the blaze of being, which is the first effect of God, has been given over to be the root perfection of existence unfurling in every creature, as the act of all acts and perfection of perfections; God is not this pure light that emanates from him, but rather the Sun itself where this light is thick and subsists. For this reason, we say, he is simple.

Among the Prolegomena for Trinity

Confessing simplicity is in absolutely no way anything else but the intentional and deliberate act of continually turning away from seeing God in the formal light of any composition: this is the position and teaching of the holy catholic church and of all her fathers, doctors, and theologians. With the above primer in mind, how is simplicity relevant for the doctrine of the holy Trinity? Simplicity is relevant insofar as it is in the veins of any living monotheism, and insofar as it preempts us from collapsing into tritheism, when we are confessing God the holy Trinity.

As I said above, so I say again: we must not say too much or too little on this point. For there is a difference, and it happens to be one that matters, between confessing simplicity, not confessing simplicity, and affirming compositeness. We must be very precise. We can confess God is not composite, and this is true and good. We can neglect to confess God is not composite, and this is not in itself an error or a problem of any sort; indeed, many pastors or church members are not brought to do this and may rest easy in not doing so. But nobody can be allowed to affirm God is composite: this is an error, and a weighty one. We can neglect to confess God is not composite, and this is not in itself an error or a problem of any sort... But nobody can be allowed to affirm God is composite: this is an error, and a weighty one. Click To Tweet

Let us recall that confessing simplicity is nothing else but negating some composition from God. Not performing a negative judgment does no harm to teaching about God in his essence (de deo uno) or in his persons (de deo trino). This is the case because we are dealing with a negation, not an affirmation: not performing an affirmative judgment (e.g., “God is love”) is blameworthy and censurable, for that is to turn away from singing divine praise, from marveling at his glory, and from proclaiming Who God Is. Not so with negative names. If I were to neglect to judge, The sun is not blue, Water is not dry, or Cats lack wings and beaks, none should be anxious about my beliefs or sanity; in fact, if you were to become anxious or upset with me for only the absence of these judgments, then I might be led to question yours!

So it is in theology, in negative names such as the doctrine of simplicity. When we broach its relationship to trinitarian theology, we can quickly say too much. But simplicity is just like part of the fence we place along a road that snakes along the mountain ridge, for no other purpose than to prevent us from sliding off into the gorges below. Simplicity does not add to our confession of Trinity, just as it does not add to our monotheism: it merely negates something of God. It is a help or an aid insofar as it has cleared the ground for us to be filled with what God has revealed about himself as Father, Son, and Spirit. So long as one is not affirming God is composite in some way, the doctrine of simplicity is never raised.

Nonetheless, neither can we say too little. The doctrine of simplicity is conscripted to do battle with any who would actually affirm positively God is composite, in any way of composition they might be tempted by and indulge (from bodily composition, to the metaphysical composition of being and essence); after that, we do not require its presence in the field of doctrine. We say this in no uncertain terms: one must not, in any way, affirm God is composite. This is an error and a devastating one, not only for Trinity, but first for monotheism. And given that my tendency and yours is to suppose God is a creature, even when I am speaking of him according to essence, simplicity must be always close by and ready to do service, when we need to combat this impulse in ourselves or in our brethren. Nobody is tempted to judge The sun is blue. But it is our native habit to judge God is composite, because we are creatures, we know in creaturely ways, we think in creaturely terms, we meet only creatures throughout this life.

And what is more, the inclination to think in terms of composition becomes far, far more difficult to refuse, when we turn to the doctrine of Trinity. This is because three really distinct persons with us and among creatures per se involves composition: for us, three is not one, and three is composite. If we could be left unbothered by neglecting this doctrine in the essence of God, we must become alarmed if we are only “not confessing simplicity” and gearing up to face the doctrine of the most holy Trinity. There are many monotheists, and few know that God is simple or have penetrating insight into what simplicity is; no destructive error is immediately at hand, like a lion to pounce upon them. And yes, it is likewise true, that there are some who have known God is Trinity, and have even developed some understanding of this mystery of the faith, and have not had clear intuition that God is simple, except in perhaps highly basic ways (such as lacking bodily composition): but this is due to God’s grace at preserving from error, and we must not be content to grow slack under his light.

Thus, banishing simplicity from the continent of Christian teaching, or granting it military discharge, is to overlook or say too little about its relation to the doctrine of Trinity. Simplicity is part of the army reserves, ever in shape, fit and robust, for when its presence is required. And its presence and service is required no more so than when navigating the doctrine of the holy Trinity.

So despite the humility of simplicity’s place in the body of Christian teaching about God, nonetheless it is very useful to meditate on particular errors about Trinity which have been preempted by first confessing simplicity. Meditating on this brings together simplicity and Trinity more thematically, in order to have a stronger hold on trinitarian teaching, because we have released our grip on what is not trinitarian teaching, through confessing the simplicity of God in his essence (de deo uno), before turning to consider God as Trinity (de deo trino).

There are many moments in the doctrine of Trinity where we are especially happy that simplicity is present with us. We may conclude with one: simplicity brings us to avoid considering the divine persons as distinct in any absolute terms. This applies for how we distinguish and constitute them as really distinct persons, and for how we perform the rest of trinitarian doctrine declaring further Father, Son, Spirit. As we become aware in the treatise on the essence of God, especially under the doctrine of simplicity, God is not divided, God is not a motley of things, God is not divisible into separate components, God is not dissolvable into pieces. And so it is that when we turn to the doctrine of Trinity, and seek out how to distinguish and constitute persons in God, we are in no way to seek to do this with something absolute in God, for this is to believe in three gods, not to confess God himself.

The common position of the catholic church on this point has thus been that the persons are really distinguished from each other and constituted as such by their relation which is founded upon origin (i.e., the relations paternity, filiation, and passive spiration), because nothing else remains to distinguish and constitute divine persons. Likewise, after we have considered the divine persons as really distinct, simplicity returns us to our confession that they are one God, and brings us to avoid expanding further our trinitarian theology in a mode which would be out of step with the confession that they are the one God. Acting out of step with this, is prevented by continually calling up simplicity which not only points out an error, but trains us in the cadence of praise for He Who Is, where every similitude can only be posited out of an ever-greater dissimilitude as its prior. As Thomas says, summarizing Lateran IV, “So much similitude between the creature and Creator is not able to be, except that the ever-greater dissimilitude be found therein, on account of this: the creature is, infinitely distant from God” (non potest tanta esse similitudo inter creatorem et creaturam, quin maior inveniatur ibi dissimilitudo, propter hoc quod creatura in infinitum distat a Deo; Thomas, Super Decr no 2).

So is the simple God who is, and who is Father, Son, Spirit.

Ryan Hurd

Ryan Hurd is a teaching fellow at The Davenant Institute and is systematic theologian whose area of expertise is doctrine of God, specifically the Trinity. His primary training is in the high medievals and early modern scholastics as well as the 20th century ressourcement movement. He has written a number of articles and regularly does translations of early modern theology sources; but his primary project is writing a systematics of the Trinity. He is currently a doctoral student at Theologische Universiteit Kampen.

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