1
Friends and Foes of the Classical Doctrine of Divine Simplicity
With these words the Westminster Confession of Faith begins its chapter, “Of God, and of the Holy Trinity” (WCF 2.1). The plain intention of the authors is to express those ways in which God is distinct from and superior to all creatures. This distinction is most broadly summarized in the affirmation that God is “most absolute.” This means that no principle or power stands back of or alongside God by which he instantiates or understands his existence and essence. He alone is the sufficient reason for his own existence, essence, and attributes. He does not possess his perfections by relation to anything or anyone other than himself.
But the question is asked: What is the ontological condition by which such absoluteness is ascribed to God? Or, put differently, what is it about God’s existence and essence that permits one to say that he is the entirely sufficient explanation for himself? The same article of the Westminster Confession supplies the answer to these questions when it states that God is “without parts.” This curious verbiage signifies the Westminster divines’ commitment to the classical doctrine of divine simplicity (DDS). It is divine simplicity that enables the Christian to meaningfully confess that God is most absolute in his existence and attributes. Adherents to this doctrine reason that if God were composed of parts in any sense he would be dependent upon those parts for his very being and thus the parts would be ontologically prior to him. If this were the case he would not be most absolute, that is, wholly self-sufficient and the first principle of all other things. Thus, only if God is “without parts” can he be “most absolute.” It is this argument that forms the central thesis of this volume: Simplicity is the ontologically sufficient condition for God’s absoluteness.
The doctrine of divine simplicity teaches that (1) God is identical with his existence and his essence and (2) that each of his attributes is ontologically identical with his existence and with every other one of his attributes. There is nothing in God that is not God. The Reformed theologian Stephen Charnock explains simplicity in terms of God’s supreme existence: “God is the most simple being; for that which is first in nature, having nothing beyond it, cannot by any means be thought to be compounded; for whatsoever is so, depends upon the parts whereof it is compounded, and so is not the first being: now God being infinitely simple, hath nothing in himself which is not himself, and therefore cannot will any change in himself, he being his own essence and existence.”
In similar fashion, the medieval theologian and philosopher Thomas Aquinas contends that, “every composite is posterior to its com-ponents: since the simpler exists in itself before anything is added to it for the composition of a third. But nothing is prior to the first. Therefore, since God is the first principle, He is not composite.” Again, the argument of both Charnock and Aquinas is that God cannot be the ultimate ontological explanation for himself or for anything else if he is composed of parts.
The theological value and implications of the doctrine of divine simplicity have been variously explained and applied throughout the history of the church, though in recent decades the classical version of the doctrine has fallen into disrepute. Many seek to banish it from Christian theology altogether while others aim to preserve it by softening its philosophical or theological austerity. It is my contention that God’s absoluteness is diminished to just the extent that one denies or softens the DDS. This argument is developed in various ways throughout the chapters of this book.
Before delving into the particular elements of my thesis, it is first crucial that we should have some sense both of the historical and present status of the doctrine of divine simplicity. My aim, then, in the remainder of this chapter is to briefly sketch the historical Christian witness to the DDS and after that to survey some of the recent criticisms of the doctrine. Following these two sections I will conclude with an initial response to the doctrine’s critics.
The Historical Witness to Divine Simplicity
Historian Richard Muller informs us, “The doctrine of divine simplicity is among the normative assumptions of theology from the time of the church fathers, to the age of the great medieval scholastic systems, to the era of Reformation and post-Reformation theology, and indeed, on into the succeeding era of late orthodoxy and rationalism.” The following is a brief sketch of what some of the church’s leading theologians have said about the DDS in the last two millennia.
Patristic Witness
The early church fathers first gave expression to the DDS in response to the classical Greeks’ philosophical quest for a single ultimate principle by which to account for the universe, that is, to discover the unity that lies back of all multiplicity. Wolfhart Pannenberg distills the basic logic of the Platonic and Aristotelian notion of simplicity that came to be appropriated by the early church fathers: “Everything composite can be divided again, and consequently is mutable . . . Everything composite necessarily has a ground of its composition outside itself, and therefore cannot be the ultimate origin. This origin must therefore be simple.” In his Against Heresies, Irenaeus appeals to divine simplicity in order to prove to certain Greek emanationists that God neither exhibited passions nor underwent a mental alteration in the production of the world: “He is a simple, uncompounded Being, without diverse members, and altogether like, and equal to himself, since He is wholly understanding, and wholly spirit, and wholly thought, and wholly intelligence, and wholly reason, and wholly hearing, and wholly seeing, and wholly light, and the whole source of all that is good—even as the religious and pious are wont to speak concerning God.”
The DDS was quickly established as a central ingredient to the orthodox Christian understanding of the divine nature. Though it was initially expressed in the apologetical conflict with the Greeks, it soon came to be used to establish the full deity of the Son and the Holy Spirit and to defend the monotheistic credentials of orthodox trinitarianism. Gregory of Nyssa argues that the Son and the Holy Spirit could not be semi-divine, as some heretics insisted, because the DDS proves the indivisibility of the divine essence. Thus, wherever the divine essence is present it must be wholly present. As for the Trinity, the DDS was used to prove the indivisible singularity of the divine essence and thus refute the accusations of tri-theism. Lewis Ayres remarks, “[T]he deepest concern of pro-Nicene Trinitarian theology is shaping our attention to the union of the irreducible persons in the simple and unitary Godhead.” It is the DDS that ensures this is not a union of three gods.
Following the Cappadocian fathers, Augustine appeals to divine simplicity in his De civitate Dei to argue for the unchangeableness of each person of the Godhead: “It is for this reason, then, that the nature of the Trinity is called simple, because it has not anything which it can lose, and because it is not one thing and its contents another, as a cup and the liquor, or a body and its colour, or the air and the light or heat of it, or a mind and its wisdom. For none of these is what it has.” In De trinitate he further elaborates on the DDS in his attempt to establish the uniqueness, independence, and singularity of the divine nature:
This passage affirms the identity of God’s existence and essence and denies that God’s attributes are in any way separable from his essence. God simply is whatever is predicated of him and none of his essential attributes is really or conceptually separable from him. The denial that God is identified “with reference to s...