Simplicity, Timelessness, and Impassibility

The three previous rungs treated God as a hypothesis to be weighed, a first cause to be argued for, or a possible being to be located in modal space. All three treatments share an assumption that the tradition would have rejected: that we already know well enough what we are talking about when we say "God" for the arguments to get a grip. Classical theism says we do not. It says that God is not one more item in the inventory of things, differing from the rest in scale, and that anyone who pictures a very powerful person outside the universe has already lost the subject.

What replaces the picture is a cluster of denials. God has no parts. God has no temporal location. God has no states brought about in him from outside. These are the doctrines of simplicity, timelessness, and impassibility, and they belong together tightly enough that a great deal of the recent literature treats them as one doctrine with three faces. Each of them is a denial rather than a description, and each of them removes something that ordinary thought about persons takes for granted. That is the source of both their appeal and their trouble.

What simplicity says

Aquinas puts the doctrine at the front of the Summa Theologiae, question 3 of the first part, before he says anything about goodness or knowledge or power. The placement is deliberate. Having argued in question 2 that God exists, he immediately says that we cannot know what God is, only what he is not, and then proceeds through a series of denials that each strip away one kind of composition.

The identity thesis is where the difficulty starts, so it is worth being clear that it is not an accidental extra. If God's goodness were something distinct from God, then God would depend on it for being good, and there would be a fact about God that God does not account for. If God's goodness were distinct from God's power, then God would be a composite of at least those two, and something would have to explain why those particular components are combined in this particular being. The tradition takes both consequences to be intolerable, so it takes the identity.

A related move follows for existence. In creatures, what a thing is and that it is come apart: you can grasp what a phoenix would be without settling whether any exist. In God, the tradition says, they do not come apart. God's essence just is God's existence, which is why God cannot fail to exist and why God is not a member of any kind that might have had other members.

Why the doctrine was adopted

Nobody arrived at simplicity by inspecting God and noticing an absence of seams. The doctrine is derived, and it is derived from a thought about dependence that also underwrites much of what earlier rungs covered.

The argument is short and its premises are not obviously false, which is why the doctrine has proved so durable. It also connects simplicity to perfect being theology in a way that is easy to miss. If you begin from the idea that God is whatever is maximally perfect and reason to the attributes from there, independence is going to come out as a perfection, since a being that owed its existence to the arrangement of components would be less perfect than one that did not. Simplicity is then not an eccentric addition to the standard list of attributes but a constraint on how the rest of the list can be held.

There is a second motivation, less often stated but doing real work. A God who has properties in the ordinary way is a God for whom there are facts not settled by God. Something would have to explain why God has just these attributes and not others, and the explanation would appeal to something other than God. Immutability follows from the same source, since a being that acquired or lost states would have a history that something outside it helped to write.

A third route runs through the Aristotelian vocabulary the scholastics inherited. Anything that can change has some capacity not yet realised, and the tradition marks this by saying such a thing contains potency as well as act. What is purely actual has no unrealised capacity at all, and therefore cannot change, cannot be improved, and cannot be composed, since composition requires parts capable of being arranged otherwise than they are. Aquinas reaches simplicity from this direction as well as from the dependence argument, which matters for the later disputes: an opponent who defeats one route has not thereby defeated the other, and defenders of the doctrine often shift between the two under pressure.

The property objection

The most influential modern attack on the identity thesis is Alvin Plantinga's, in Does God Have a Nature?, the Aquinas Lecture he delivered at Marquette in 1980. The objection is one paragraph long in substance and has occupied the literature ever since.

If God is identical with his goodness, and goodness is a property, then God is a property. Properties are abstract objects. Abstract objects do not know anything, do not act, and do not love anyone. So the identity thesis, taken at face value, entails that God is not a person, which is a conclusion no defender of the doctrine has ever accepted. A second consequence follows from the same premise: if God's goodness and God's power are both identical with God, they are identical with each other, and the apparent multiplicity of divine attributes is an illusion produced by our vocabulary rather than a feature of anything.

Defenders have taken two routes. The first insists that the identity claims are not ordinary identity claims at all, that the vocabulary of the doctrine is governed from the start by the tradition's refusal to say what God is, and that Plantinga has read a metaphysical thesis off what was meant as a set of restrictions on speech. This route is available, but it has a price: the less the doctrine asserts, the less it can do the explanatory work that motivated it.

The second route accepts that the doctrine asserts something and tries to say what. Jeffrey Brower's proposal, in "Making Sense of Divine Simplicity" (2008), is to read the identity claims through truthmaker theory. Ordinary predications about a substance are made true by something; in creatures, the truthmaker for "Socrates is wise" is Socrates together with a distinct property he instantiates. Brower's suggestion is that in God's case the truthmaker for every intrinsic predication is just God, the concrete being, with no distinct property required. On this reading God is not identical with a property. God is what makes the property-talk true. Whether that is a defence of the traditional doctrine or a replacement for it is exactly what the subsequent literature has argued about, with Noël Saenz among those pressing the case that truthmaker theory cannot save it. Eleonore Stump, in Aquinas (2003), takes a different line, arguing that simplicity earns its keep by blocking brute facts about God and by giving the tradition a clean answer to the Euthyphro dilemma, since a God identical with goodness neither commands arbitrarily nor answers to a standard above him.

Modal collapse

The sharpest contemporary problem is not about properties but about freedom, and it has generated more journal pages in the last decade than any other objection to classical theism.

Ryan Mullins and Shannon Byrd, in "Divine Simplicity and Modal Collapse: A Persistent Problem" (2022), argue that the recent replies have not touched the argument and that the problem is exactly as bad as it looks. Mullins had already pressed a version of it in The End of the Timeless God (Oxford, 2016), where the case is that simplicity together with pure actuality leaves God with no room to have done otherwise.

The most discussed reply charges the argument with a modal fallacy. The claim is that the inference slides between the necessity of God's act and the necessity of what that act produces, and that the two come apart: one and the same necessary act can have a contingent effect, because the act is characterised by what it accomplishes rather than the other way round. Whether this works depends on a question about divine action that classical theism has never fully settled, namely whether an act can be individuated independently of its result. If it cannot, the reply gives up the identity it needed.

Joseph Schmid has pushed the dispute past the original formulation. His argument, in "The Fruitful Death of Modal Collapse Arguments" (2021) and "From Modal Collapse to Providential Collapse" (2022), is that even if the modal argument fails as stated, a weaker relative survives: on simplicity there is nothing in God that varies with what he creates, and so nothing that could constitute his intending one world rather than another. Providence, not just contingency, is what goes. The upshot of the exchange is that the debate is not really about modal logic. It is about whether classical theism can give any account of divine action at all, and both sides now largely agree on that much.

Timelessness

The second denial removes God from time.

Boethius gives the definition the tradition works from, in the fifth book of The Consolation of Philosophy, written while he was awaiting execution around 524. His formulation is that eternity is the complete possession all at once of interminable life, and the point of the phrase "all at once" is that God's life is not spread out. Boethius introduces it to solve a problem about foreknowledge that later rungs take up, but the doctrine has independent motivation. A being with a temporal location has one more thing true of it that it did not choose. A being whose life is spread across earlier and later parts is composite in a further way, since the parts of a life are parts. Simplicity, taken seriously, brings timelessness with it.

Eleonore Stump and Norman Kretzmann's "Eternity", in The Journal of Philosophy in 1981, is the article that made timelessness a live position again in analytic philosophy of religion. They take Boethius as the tradition's spokesman and resist the common assumption that a timeless being must be frozen or lifeless: eternity on their account is a mode of duration, not the absence of one, and they construct a relation of eternal-temporal simultaneity to explain how a timeless God can be present to each moment of a temporal world without being located in any of them. The construction is technical, and the objection it invites is that the relation cannot be simultaneity in any recognisable sense, since simultaneity is transitive and this one deliberately is not. Omnipresence gets a parallel treatment: God is present to every place without occupying any, which is easier to accept once you have accepted the temporal version.

Sempiternity

The rival position keeps God in time.

Nicholas Wolterstorff's "God Everlasting", published in 1975 in God and the Good: Essays in Honor of Henry Stob, is the paper that put the option back on the table. His argument does not appeal to modern physics or to scripture read literally. It appeals to what knowledge requires.

The timeless theist has a standard reply: God does not know tensed facts, because there are none. On an eternalist view of time all events are equally real and the appearance of passage is a feature of our perspective, so God knows the whole four-dimensional array and nothing he knows changes. This reply is available, but notice what it costs. The defence of a doctrine about God now depends on a contested position in the metaphysics of time, and if the presentist is right about time then the timeless God is in trouble.

Mullins presses exactly this. His case in The End of the Timeless God is that timelessness is incoherent on presentism, because a God who exists but exists at no time has no relation to what is actual, and unattractive on eternalism, because it purchases coherence at the cost of everything the doctrine was supposed to protect. Whether the dilemma holds is disputed, but it has set the terms: nobody now defends timelessness without saying which theory of time they are assuming.

Impassibility

The third denial concerns whether God can be affected.

The motivation is the same as before. Something that acts on God is something on which God depends, and a God whose inner states are caused by creaturely events is a God partly made by his creatures. Impassibility is what independence looks like when you apply it to the emotions.

Twentieth-century theology turned against the doctrine with unusual unanimity, and the turn was driven by history rather than by metaphysics. Jürgen Moltmann's The Crucified God, published in German in 1972, argues that a God incapable of suffering is a God incapable of love and, after the camps, a God not worth having. The passibilist case is that the impassible God of the tradition is an import from Greek philosophy, that the God of the biblical texts grieves and relents and is moved, and that the fathers let the philosophy overwrite the texts.

Two distinctions are worth keeping straight before assessing the charge. Impassibility is not indifference. The doctrine denies that creatures cause states in God, not that God wills the good of creatures, and a defender can hold that God's love is maximal while denying that it fluctuates with what its objects do. Impassibility is also not the same as immutability, though it entails it on most formulations: a God could in principle change on his own initiative without being changed by anything external, so a passibilist who wins the argument about external causation has not automatically won the argument about change.

The harder pressure on the doctrine within Christian theology is internal rather than philosophical. The incarnation asserts that God underwent a human death, and any impassibilist has to say in what sense that is true. The classical answer distributes the predicates between the two natures, so that suffering is attributed to the incarnate God in respect of his humanity and not in respect of his divinity. Critics call this a verbal manoeuvre that saves the doctrine by removing its subject from the event. Paul Gavrilyuk's The Suffering of the Impassible God (Oxford, 2004) challenges the history directly. His argument is that the fathers were not asserting that God is emotionally inert; impassibility functioned for them as a qualifier on divine emotion, marking which ascriptions of feeling to God are not to be taken in the creaturely way, rather than as a blanket denial. On this reading the standard story about a Hellenistic takeover is a modern construction, and the patristic writers were doing something more careful than either side of the modern debate has credited them with. The historical point does not settle the philosophical one. It does mean that a passibilist who argues by claiming the tradition lost the plot has more work to do than they thought.

Next

The disagreement sketched here has a name and a shape. Those who keep the classical package and those who trade it for a God more like a person in the ordinary sense have separated into two camps that increasingly talk past one another. The next rung takes that division as its subject, sets out what theistic personalism actually claims, and asks whether the two positions are rival specifications of one concept or two different concepts sharing a word.