Summa Theologica - God is simple

Im reading Suma Theologica and it keeps saying that God is simple. Im a little over 300 pages in but Im having a hard time trying to understand God as simple considering He is the creator of everything. Any help understanding this concept?

There are many arguments, some follow. God is not a composite, composed of form and matter. God is the First Mover and cannot be moved since only bodies are moved. God is the most noble being, and if God had a body it would need a soul to animate it, therefore not the most noble.


All that i understand. Im having a hard time with the idea of simple. One would think He would be the most complex entity out there since he created everything

Can you provide one proof that God would be composed of parts?


I do not think he is suggesting that, only that he is having difficulty reconciling simplicity with omnipotence and omniscience.

Rather than the Summa, which is quote lofty, dense and highly philosophical, maybe some apologetic work by Professor Peter Kreeft, for example, would make it more comprehensible.


This might help:

Yes, I have it and :heart: it.


Wasnt arguing he has parts. Is that whats meant by simple? That Hes not made up of parts?


Yep that is exactly what St. Thomas meant by “simple”.
Many times there are invisible barriers imposed by language and what words meant and mean then and now.


OK, but I thought you understood no parts from “God is not a composite”. Simple is without parts.

Oxford Dictionary

simple, adjective: 3. composed of a single element; not compound
composite, 1. adjective made up of various parts or elements.


I thought simple was a virtue?

Meaning honest, straightforward, pure, without duplicity, etc.

God is pure spirit. How is a spirit simple or complex, etc? Spirit has no matter. How would St Thomas even arrive at such a conclusion one way or another? We can’t examine God under a microscope or through a telescope. He isn’t a part of creation.

Think of it this way. God is simple. We, however, are not. All the divisions, subdivisions, and reductio ad absurdum found when speaking about the nature of God are created by man in an an attempt to comprehend our Creator. The only divisions in God are those that he revealed to us in mystery. As composite creatures, we can only perceive and comprehend in composite terms, hence the complexity of our explanations.

If you like podcasts, Bishop Barron recorded a talk on Divine Simplicity. You can find it on SoundCloud. I’d search for “Bishop Barron + William Lane Craig - Symposium Part 1”

Exactly why he wouldn’t have attributes that make something a creature.

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OP, the Summa Theologica is a thirteenth century summary of theology meant for those training in theology. A summary is not exhaustive or comprehensive. I am not discouraging you from reading it as I think it is a very good work. However, it is not meant as an introduction to philosophy or theology. St. Thomas’ intended audience is assumed to some philosophical and theological education already. This ST is the sparknotes to that education (I may be slightly exaggerating, but only a little. It’s a nifty handbook, educational, but also in some senses a refresher). Just keep that in mind.

God as Simple is something he assumes his reader is already familiar with. What he means by Simple is that God is not made of parts. He does not mean God is easy to understand. (In fact, God’s absolute simplicity is something difficult for our minds to grasp. Our minds are used to picking out parts and categories and specific differences.)


I must be missing something if God isn’t considered to have parts - whatever “parts” means in this context IDK anyway.

Why isn’t Jesus considered a part? He had a body. Why isn’t His body, the Eucharist, considered a part since it’s His actual flesh and blood?

The statement that God is Simple is specifically concerning God’s divine nature. The human nature united to the divine person of the Son is a non-eternal creature. Jesus’ human nature “comes with” parts.


Is this a theological doctrine, a theological hypothesis, or a theological tradition? Or something else?

The Fourth Lateran Council taught that God is “Father and Son and Holy Spirit: indeed three persons but one essence, substance, or nature entirely simple.” Vatican I taught, God “is one, singular, altogether simple and unchangeable spiritual substance.” And it has been taught by many Church Fathers. Simple in this context meaning without parts and referring to God’s own substance. Ott’s Fundamentals of Catholic Dogma textbook states Divine Simplicity is de fide doctrine.


I’ll just add knowing this in itself make one better at living Christian values. It’s more for one interested in theology or apologetics and defending the faith against certain criticisms or misrepresentations.

What it means is that God is metaphysically simple – in other words, “not made of parts”. You’re thinking of a different definition, such that the opposite of “simple” is “complex”. Here, in this context, the opposite of “simple” is “composite”.

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