This is an essay that I wrote for completion of a course I took on St. Thomas Aquinas. The opening quote comes from the Lectures on Faith, which was not written by Aquinas, but sets the tone for the essay.
April 16, 2008
“Let us here observe, that three things are necessary in order that any rational and intelligent being may exercise faith in God unto life and salvation. First, the idea that he actually exists. Secondly, a correct idea of his character, perfections, and attributes. Thirdly, an actual knowledge that the course of life which he is pursuing is according to his will.”
— Lectures on Faith
The former method has the advantage of being authoritative and therefore establishes the foundation of theological investigation. The truths taught in this way are not open to deliberation or questioning. They are the premises that will be used in the syllogism. The second method has the advantage of being able to answer questions that are not immediately apparent in the revelation. In other words, the second method is the application of what is reveled, the derivation of the syllogism. This method has the disadvantage of being capable of error, while the former, at least in the context of a particular religion, is not. Even though there is the possibility for error in the second method, it has the ability to correct those errors, while in the first method, in the context of the religion, there is no mechanism to correct errors.
When theologians address a certain question they typically do so with the intent to preserve their premises, or their faith, and not to question it. As they use reason to understand the nature of God theologians usually take certain premises to be invariant and all other conclusions must conform to those premises no matter how strange and unintelligible the conclusion is. In other words, there are some premises that cannot be shown to be inconsistent or contradictory regardless of the contradictory nature of the conclusions. The premises that are given this untouchable status are usually the premises regarding the fundamental nature of God, because the fundamental nature of God is the defining characteristic of any given religion. If these basic premises were questioned or rejected as irrational then this would be a rejection of the religion itself, a rejection of the faith, and no true theologian would want to do this.
When Thomas Aquinas sets forth the basic premises of his religion one of the most fundamental is the doctrine of divine simplicity. With this doctrine Aquinas attempts to preserve the existence, nature and sovereignty of God.
As will be noted, this doctrine leads to some rather difficult conclusions and raises other questions that tend to complicate Aquinas’ theology unnecessarily. Aquinas argues that the doctrine of divine simplicity is necessary in order to preserve the nature of the Christian God as the greatest conceivable being. Because the Christian God must be omnipotent and absolutely sovereign, the only conceivable being that can fulfill these requirements is one who is utterly simple. But in order for God to be utterly simple He must be without body, parts or characteristics. Additionally God cannot have a nature because that would imply that He is not absolutely simple, but a simple God must be identical with His nature. Thus it is with all of God’s “characteristics”. They cannot be characteristics in the normal sense of the word, as something that is possessed by a being, but rather these characteristics are identical with God, but are not identical with each other. These simple statements may seem contradictory but if we consider Aquinas’ reasons for holding to this idea we can see that he was motivated by his faith to preserve truths, even in the face of logical contradictions, that he thought were right.
Let us first consider Aquinas’ argument for divine simplicity. In order to understand his argument we must first know his basic premises. God is the first being and is the first, and unmoved, mover. Because God is the first being He is uncaused, and is the first efficient cause. God is also purely actual and has no potentiality. And finally “God is absolute form, or rather absolute being” (p. 34). There is a suppressed premise here that God is sovereign, and this premise will be discussed in greater detail later on. Aquinas defends these premises with his arguments for the existence of God, as they are given in Question 2, Article 3. In that section, Aquinas gives five proofs for the existence of God starting with a proof for the first mover. Because there is motion in the world and the motion of an object comes from the action of another, thereby reducing the object from potentiality to actuality, there must be a first mover because there cannot be an infinite regress of movers. This first mover Aquinas calls God. Aquinas gives a similar argument for efficient causes, necessary existence, fundamental being, and universal order. All the things that are fundamental, or first, Aquinas calls God. While these arguments are interesting and merit consideration, for our purposes the important point is that they place God as the first and origin of all things.
With these premises in place let us consider the doctrine of divine simplicity and its implications. For a being to be absolutely simple it cannot have extension or parts because if that being has extension it can be divided and if it has parts then those parts can logically be separated from the being. For example a man is made up of different parts, including hands, legs, arms and all the other body parts. These body parts can be separated from the man but the individual parts by themselves do not make up the man. As Aquinas puts it, “nothing composite can be predicated of any one of its parts” (p. 34). But God as absolute form cannot be reduced to parts. If there were anything to be taken away from God then He would not be God, or rather the result would contradict the definition of God. If a man looses a hand then he is still a man. If enough parts are taken away from the man then he will cease to be a man (i.e. he will die). With God there are no parts that can be removed from Him, so he cannot cease to be.
If we consider the basic concepts of God’s nature and being then apparently there exist some things that God possesses that can be defined as distinct from Himself, namely his nature and being. This presents a problem because God is supposed to be the first being, that is, all things come from Him including His attributes. Alvin Plantinga sets up this predicament in his article “Does God Have a Nature?” when he discusses God’s essential properties. If God has properties that are essential to His nature then He could not not have them. Plantinga then explains, “If so, then it isn’t up to [God] whether he has that property; his having it is in no way dependant upon his own decision or will. He simply finds himself with it; and that he has it is in no way up to him” (p. 227). If God has properties that define his divinity then he cannot be the first cause. There must be another cause prior to God that has determined His attributes. For example, if God is omniscient and, He as the first knowing being, possessed all knowledge then there must be something else that determined what is meant by all knowledge and having all knowledge. This means that there is a property that God has that, in order to be God, He must posses and if not then He is not God.
So to explain this concept in a different way, we will consider an arbitrary being that exists. We will not make any assumptions about this being other than it has being and it has existence. We will expand our understanding of this being by saying this particular being is also omniscient, omnipotent and omnipresent. If this being has these properties then it did not determine what it means to have the three omni’s. That is, the definitions came from an outside source, or something else determined what it means to have all power, to have all knowledge and to be in all things. This means that there is something else that is primary that has determined the infinite power, knowledge and presence of God, which is in contradiction with the definition of God as the first being. Thus to prevent this contradiction of definition we must consider the arbitrary being as somehow being able to determine what it means to have the three omni’s while still being the first being. To get around this difficulty Aquinas states that, “God is not only His own essence…but also His own being” (p. 30). Because God is identical to His nature then His “qualities”, if they can be called that, are not prior to Him and are not determined by anything else. A term that can rightly be used here is aseity. Aseity, from Latin a se (a-from se-self), is a word that can be used to describe the concept of God being identical to his nature.
Eleonore Stump explains this concept in her book Aquinas using similar language but also mentions something that is worth noting here. “Therefore, unlike all other entities, God is his own being” (p. 97). She mentions that “unlike all other entities” God can be identical to His own being. This certainly sets God apart from all other entities in that He does not depend on anything else for His existence. As an absolutely simple being God cannot not exist and He cannot be destroyed. By holding to the doctrine of divine simplicity Aquinas can prove the existence of God and can show that God is good, perfect, infinite and eternal. As a man of faith this is very convenient for Aquinas because he would not want the foundation of his faith to be shaken.
As previously mentioned there is an unspoken premise that God is sovereign. To see this let us consider a simple example of a king in his own kingdom. As a monarch the king can command and he will be obeyed. If he is an absolute monarch then he will be obeyed absolutely. But it is conceivable that the king can be dethroned by forces within or without his kingdom. The king may be sovereign, but only by the willingness of his subjects or the inability of foreign powers from invading his kingdom. But in all matters pertaining to the ability of the king to command we say that he is sovereign. Extending this concept to God we see that the “King of kings” must be sovereign on a much higher level. An earthly king cannot command and bring the dead to life for “With men this is impossible; but with God all things are possible” (Matt. 19:26). With God there can be no foreign power that can invade and take away His kingdom, for if that were possible then we could not have perfect faith in God. Thus in order for God to be sovereign in the universe and to be the creator of heaven and earth then there can be nothing that could prevent Him from fulfilling His words or from continuing His existence as God. That is, God cannot cease to be God. For Aquinas the only way that this can be true is if it is a logical impossibility for God to not be God. There can never be a time, place or situation in which something has power or control over God, for if that were possible then it is logically possible for that thing to destroy God, meaning it is logically possible for the being that is God to not be God. For Aquinas this is equivalent to saying that the first cause is not first, which is a contradiction in terms.
To prevent this contraction Aquinas holds to the idea of divine simplicity and gives several arguments for it. In this way Aquinas can show that God is infinite, eternal and perfect, and his conclusion is not open to question because it is based on reasoning that cannot be rationally denied. This is very convenient for Aquinas because it gives a very sure foundation to his faith and allows him to continue with his theological investigation knowing that its foundation will not fail. The potential problems of the doctrine of divine simplicity are acceptable to Aquinas because of the potential benefits of having an indisputable theology. Unfortunately Aquinas’ acceptance of divine simplicity leads to complications that call into question, at least for some, his entire theology.
If we consider the doctrine of divine simplicity and ask a few simple questions we immediately run into some complex problems. While there may be many ways to approach this I will only consider some common questions to illustrate the potential problems. First, how do we know an absolutely simple God? Aquinas states quite clearly at the beginning of his section on divine simplicity that “we cannot know what God is, but rather what He is not, we have no means for considering how God is, but rather how He is not” (p. 25). This seams like a rather odd way to begin an investigation into the nature of God, by stating that He cannot be known. A statement like this can very easily be satirized, causing the rest of his work to be ridiculed as irrational. To be fair Aquinas does explain how man can know God, through the intellect and by the grace of God. Aquinas is not making the claim that nothing can be known about God, thereby invalidating the need or possibility of a theology, but rather we come to know God by removing from our understanding of God all things that do no pertain to Him, such as “composition, motion, and the like” (p. 25). When this process is complete, then a man may know God.
So Aquinas may have an answer to that question but like the hydra of Greek mythology, with every question answered more questions are created, such as, how can there be the Father, the Son and the Holy Ghost in God? In other words how can there be three in one? This seems like a contradiction of terms. Again Aquinas covers these questions and answers with an explanation of the relations in God that constitute the divine persons (see Q. 29 and Q. 30). But again we have the problem of the hydra, with more questions that come up to replace the ones that are answered. Perhaps we have an infinite regress of questions that can be asked regarding the nature of God? But then this would contradict Aquinas’ proof that there must be a first cause. So how do we escape or are we left to agree with Nietzsche when he said, “[Philosophers] place that which makes its appearance last—unfortunately! for it ought not to appear at all!—the “highest concept,” that is to say, the most general, the emptiest last cloudy streak of evaporating reality, at the beginning as the beginning” (Nietzsche, p. 109)? This leads to the question, is all of this discussion useful or am I just adding to the “multiplication of useless questions”? Perhaps there is a way to preserve the sovereignty of God without appealing to the doctrine of divine simplicity, and perhaps a different approach would be more advantageous.
To introduce this alternative I should address one final question, not typically asked in conjunction with the doctrine of divine simplicity. How does the doctrine of divine simplicity affect faith? I answer that the doctrine of divine simplicity destroys faith. If God is of such a nature that He cannot not exist then we cannot have faith in Him. Aquinas argues that the existence of God is self-evident (Q. 2 A. 1) in such a way that if someone understands the concept of existence then they automatically know that God exists, because He is existence. Undoubtedly Aquinas could give arguments as for why we can still have faith in God, but I counter that the doctrine of divine simplicity reduces God to an absolute known. There can be no question of His existence, His perfection, His infinity, His immutability and His unity. Because God is so absolutely determined, to have faith in God cannot be an action of the intellect, but rather it must be an apprehension of reality. Because of the absolutist nature of a simple God, there is no need to have faith in Him, but all that is needed is to show the unbelieving the essence of God and then they cannot deny it. In the process of man’s search for God man cannot have faith in what cannot be denied.
Perhaps it would be illuminating if we are to turn to one of the oldest philosophical tools available to man, a chair. This philosophical tool has been used since Plato, both as an example and as a resting place, but here let us use it as an example. If I were shown a chair and asked if I knew the chair existed I would reply “Yes”. If the person showing me the chair asked me if I was sure that the chair existed, then I could walk over to it and pick it up and heft it and feel it and use any and all of my senses to know that it exists. If the person showing me the chair still questioned me regarding its existence then I would wonder as to his sanity. If he insisted that I must have faith that the chair exists then I would reply that I do not have to have faith that the chair exists because I know that it exists. While I could continue with this, my point is that we cannot have faith in what is shown and what cannot rationally be denied (here I use the common definition of rational). In order to have faith there must exist the logical possibility of there being a contrary.
The doctrine of divine simplicity removes the logical possibility of the non-existence and destruction of God. As rationalized by Anselm, “For, whatever is composed of parts is not altogether one, but is in some part plural, and diverse from itself; and either in fact or in concept is capable of dissolution” (Deane, p. 24). An absolutely simple being cannot logically be divided or destroyed and thus it removes the possibility of an absolutely simple God not existing. In logic this is known as the fallacy of the suppressed correlative. If we remove the possibility of God not existing then we can logically ask the question, what does it mean for God to exist? If we agree with Aquinas and hold to a God that is absolutely simple then we run into problems and we repeat the cycle of questions regarding the nature of God. How do we escape from this cycle? We can escape if we do not require that the destruction of God must be a logical impossibility.
In his article “Must God Be Incorporeal?” David Paulson questioned the logical possibility of the destruction of God’s body. He argued that if we conceive of God’s body as infinitely divisible “bits of matter” then it can be logically possible to destroy God’s body and He would not then be all powerful if He were actually destroyed. “But even if we granted that the destruction of any body is consistently thinkable, what difference would it make? Our faith in God and his promises is ultimately personally grounded in the integrity of the divine character and will, and not in the mesh of conceptual necessity” (Paulson, p. 83). If the objection were to be raised that because there exists the logical possibility that God can cease to be God, He cannot be omnipotent then I would answer that, He cannot cease to be God, not because it is a logical impossibility, but because He is God and cannot actually cease to be God. If I am asked how I know this then my answer would be, “By faith”.
When Aquinas began his Suma Theologica he did it with faith in God and faith in His goodness and nature, but unfortunately he made the mistake of assuming that a logical possibility was the same thing as an actual possibility. Aquinas relied upon his own understanding and reason to answer a question that had already been answered through revelation. He wanted to know the nature of God, but he only had to look as far as the revelation of God in our Lord Jesus Christ. If Aquinas had taken the embodied, resurrected and glorified Christ as the basis for his idea of God, then his theological investigations may have been very different and he may have avoided some of the complexities that plagued his explanation of an absolutely simple God.
So what are we left with, if we reject the doctrine of divine simplicity? We have a God that can have a body, parts and passions. He does not have to be the unmoved mover, an immutable and untouchable God. He can be a God that is moved with compassion and feels after His children in love and mercy. He can look upon His creations and weep when they choose evil and rejoice when they choose good. He can be our father and our friend. It may be logically possible for God to be weak, for God to be evil and for God to be destroyed, but He is not and cannot and that makes Him the most powerful God.
Deane, S. N. trans., Saint Anselm, Basic Writings, Proslogium. LaSalle, Illinois: Open Court Publishing Company, 1966.
Nietzsche, Friedrich. “Reason” in Philosophy. in Philosophers of Process. ed. Douglas Browning and William T. Myers. New York: Fordham University Press. 1998
Paulsen, David. “Must God be Incorporeal?”, Faith and Philosophy. Vol. 6, No. 1. 1989.
Pegis, Anton C. ed. Basic Writings of Saint Thomas Aquinas. Two Volumes. Indianapolis: Hackett Publishing Company, 1997.
Plantinga, Alvin. The Analytic Theist. ed. James F. Sennett. Grand Rapids, Michigan: William B. Eerdmans Publishing Co. 1998.
Stump, Eleonore. Aquinas. London: Routledge. 2003.