Many contemporary Protestant analytic philosophers of religion deny the doctrine of divine simplicity (DDS). While DDS was historically the predominant Christian view of God’s nature, it has in recent centuries become controversial among Protestant philosophers and theologians. The typical objections to DDS include things such as 1) the doctrine is unintelligible, 2) the doctrine removes all contingency in the world and 3) the doctrine is incompatible with Scripture. Much has been said on both sides of this debate in recent years. Instead of rehashing this debate, what I hope to do below is outline 3 areas where the denial of DDS leads to difficulties in the area of apologetics. What I will show is that the above listed difficulties of DDS notwithstanding, a denial of DDS significantly hampers Christian apologists in at least three areas which I will discuss below. Such an apologetic problem doesn’t prove that DDS is true, but it does occasion a reconsideration of the doctrine which was denied on the grounds that it was too difficult to defend. Let’s look at each of the ways in which a denial of DDS hurts Christian apologetics.

What is Divine Simplicity?

Briefly, the doctrine of divine simplicity is the view that in God, there is no composition whatsoever in God either physical or metaphysical. This doctrine was affirmed at both the ecumenical councils of Lateran IV and Vatican I and is accepted in one form or another by Eastern Orthodox and historic Protestant theologians as well. While the specific implications of simplicity and the manner in which simplicity is described has varied historically, all those who affirm divine simplicity affirm that God, radically unlike all creatures, is in himself utterly simple. The doctrine is one which distinguishes classical theism, from so called neo-classical theism which denies divine simplicity.

Brute Facts

The most immediate disadvantage a denier of divine simplicity has is that they must concede to the atheist the possibility of brute necessary truths. On DDS, God’s existence is necessary (as opposed to contingent) but the necessity is not inexplicable. Rather, there is an account of why God must exist. In Thomism for instance God just is ipse esse subsistens, the sheer act of being itself. His nature is not a composite of essence and existence standing in need of something external to himself to unite the two, but rather he himself just is Being. As Being itself he cannot not exist.

By contrast, deniers of DDS typically hold that God exists “by a necessity of nature”. That is, it is just part of God’s (possibly composite) nature that he exist necessarily. However, positing that something exists necessarily is not an explanation of its existence. Some things which are necessary depend upon others that are necessary as well for instance almost all mathematical and ethical truths. Needless to say it would be hard to earn a PhD in math by merely asserting that some unproven theorem is necessarily true rather than showing how the theorem is derived and explained from prior ones.

One attempt argue for God’s necessity is to posit that God is the greatest conceivable being. One might argue that a being who is necessary is greater than one which is contingent. Thus, God must be necessary. This argument however does not get the the nature of God’s necessity. Is it brute or is it explained in some way? Positing merely that God must be necessary does not avoid the issue we are putting forward here.

Denial of DDS also raises the question of what limits other things from not existing necessarily? Could an angel exist by the necessity of his nature? Could the universe? Most Christians would deny the latter but they have undoubtedly opened the door for this objection.

Graham Oppy, one of the most prominent contemporary atheist philosophers argues for just such a view. Oppy argues that by positing that the universe exists necessarily, then atheism is a simpler and thus better hypothesis than theism since it requires postulating fewer entities than theism since it need not posit God’s existence. The kind of necessity Oppy applies to the universe is what we might call brute or unexplained necessity. While a denier of DDS might disagree with Oppy, they do seem to agree that positing something as brutely necessary is legitimate. The non classical theist then has to get into the muddy waters of brute necessity and argue for the superiority of theism over atheism. From the perspective of classical theism, their position is already compromised.

Arguably¹, on classical theism, and classical theism alone, there is no brute necessity or brute facts of any kind. Thus, any attempt by an atheist to posit such makes the case for atheism much weaker in comparison to classical theism. By contrast, the non classical theist does not have this advantage and finds himself inside the messy and chaotic world of arguing between alternative views, both of which posit unexplained entities (e.g. God, or ‘necessary’ laws of nature) to explain the world.

The Euthyphro Dilemma

The Euthrphro dilemma, so called because of its presence in Plato’s dialogue Euthyphro, poses a dilemma challenging the notion that the gods (or God in our case) are the ground of morality. A modern version of the dilemma might look like this

1. Either something is good because God wills it or God wills it because it is good.
2. If something is good because God wills it, then if God willed something apparently evil like torture, then torture would be good.
3. On the other hand if something is willed by God because it is good, then goodness stands outside of God.

2) is unacceptable to many because it seems to make morality arbitrary. If God had willed that rape and torture were good, then we would be obligated to do those things which seems absurd. 3) also is unacceptable because almost all Christians, particularly apologists who put forward the moral argument for God’s existence, want to ground goodness in God not as something independent and outside of God.

As has been noted however, classical theism, in its affirmation of divine simplicity bypasses this dilemma altogether. Since God is the utterly simple ground of all being, God is goodness itself. It is not something that stands outside of him and thus 3) is clearly false given classical theism. Because God is perfect goodness itself, God would never will anything contrary to his own nature and thus would never arbitrarily will something that is evil (2). Classical theism then implies that the Euthyphro dilemma is false; God neither is subject to a higher moral law nor does he arbitrarily command things.

Non classical theists like William Lane Craig, perhaps the greatest Christian apologist of the last 50 years, also try to give the same answer. Craig says for instance that God is in fact what Plato thought of as “The Good”². Thus Craig says, God only commands what is in accord with his nature. However, Craig is arguing parasitically and incoherently at this point. Craig is explicitly appealing to something from classical theism, namely the identification of God with goodness itself. How Craig, who does not hold to classical theism can endorse this view is unclear. Certainly Craig argues that God is morally perfect but that is not the same as God being goodness itself. The archangel Michael and, on Catholic theology, the Virgin Mary, are morally perfect and yet neither is God. Craig’s appeal to the good is also incoherent because Craig denies that abstract concepts such as goodness actually exist. Thus, it is hard to claim that God is what Plato thought of as the good when one denies the existence of the good.

Thus, the Euthyphro dilemma, easily answered by classical theism, seems to require classical theism to answer it. Abandoning divine simplicity then opens oneself up to this ancient argument.

Abandoning the Trinity and the Incarnation

On the surface level, the doctrine of the Trinity seems to pose a problem for DDS.³ After all, if God is utterly simple in himself, how can he exist as three distinct persons? This is a good question and it is true that at face value, the trinitarian defender of DDS has some explaining to do. However, the denier of DDS is not off the hook either. In fact, I argue that a denial of DDS leads to rejecting the doctrine of the trinity as it was articulated by the first ecumenical councils of the Church. We will look at two prominent deniers of DDS and see how, precisely because of their denial of DDS, they must in turn deny credal trinitarian and Christological orthodoxy.

First, let us look at Ryan Mullins, one of the most prominent critics of DDS in philosophy of religion today. Mullins for instance argues that the Christology coming from the councils of Chalcedon (451) and II Constantinople (553) are incoherent because why they assert that Christ is one person with two natures, the way in which they espouse that view, by positing a “three-part” Christology, i.e. that Christ is the union of the divine Logos along with a human body and soul, implies that Christ is actually two people. Mullins admits that this three part Christology “eventually became the orthodox position” and that an alternative two-part view which he seems to favor was rejected “because of its associations with Arianism and its incompatibility with divine simplicity“⁴ (emphasis mine). Mullins, having rejected DDS, has no problem arguing against the classic three-part Christology and thus rejecting the christology of the fourth and fifth ecumenical councils.

Similarly, William Lane Craig also holds to a heterodox trinitarian theology. Craig, like Mullins, fails to affirm the trinitarian processions (though it is not 100% clear if he denies them)⁵, and sees the persons of the trinity as “parts”⁶ of God each having their own set of cognitive faculties (intellect and will). Craig admits that viewing the persons as parts of God was condemned in the patristic and medieval ages, “probably under the influence of the doctrine of divine simplicity”.

In both cases we can see that divine simplicity was a deciding factor in determining what became credal orthodoxy. Mullins and Craig, both in their denial of DDS, in turn deny the historic and credal views on the trinity and the incarnation so central to the Christian faith. While we might praise much of the work William Lane Craig has done for Christian apologetics, sadly, he isn’t defending the fullness of the faith but, because of his denial of DDS, defends hollowed out versions of the central tenets of Christianity.

Summary

We have looked at three ways that a denial of the doctrine of divine simplicity is damaging to Christian apologetics. First, it opens the door to atheist appeals to brute facts to explain the world apart from God. Second, it opens the door to the age old Euthyphro dilemma. Lastly, and perhaps most importantly, it seems that in their denial of DDS, contemporary Christian philosophers and apologists have abandoned the credal teachings on the trinity and incarnation, thus compromising the central doctrines of the Christian faith. None of what has been said proves that DDS is true. However, given that DDS is often abandoned because of the supposed difficulties it creates, it is worth reflecting on the difficulties that denying DDS creates. If such difficulties are great, perhaps, the denier of DDS should revisit his objections this classic doctrine once again.

1. Pat Flynn and Christopher Tomaszewski are two good Catholic philosophers who have argued to this effect e.g. here. ↩︎
2. Craig, William Lane, and J.P. Moreland. Philosophical Foundations for a Christian Worldview. Downers Grove, IL: InterVarsity Press, 2003. pg 491 ↩︎
3. Ryan Mullins. “Simply Impossible: A Case against Divine Simplicity.” Journal of Reformed Theology 7 (2013): 183-203. ↩︎
4. Ryan Mullins. “Classical Theism, Christology, and the ‘Two Sons’ Worry.” International Journal of Systematic Theology 20, no. 4 (2018): 448-467. Accessed July 16, 2024 ↩︎
5. Craig says, “For although credally affirmed, the doctrine of the generation of the Son (and the procession of the Spirit) is a relic of Logos Christology which finds virtually no warrant in the biblical text and introduces a subordinationism into the Godhead which anyone who affirms the full deity of Christ ought to find very troubling” ↩︎
6. Ibid., “[T]he persons are not parts of God in the sense in which a skeleton is part of a cat; but given that the Father, for example, is not the whole Godhead, it seems undeniable that there is some sort of part/whole relation obtaining between the persons of the Trinity and the entire Godhead.” ↩︎