Form vs structure, and what it means for virtual existence

A common but mistaken tendency when trying to understand hylomorphism is to equate form and structure and matter with the elements in that structure.1 This tendency is unsurprising, since modern science has taught us how to think about reality in terms of its physical and biological structure, but it is still a mistake. When Aristotle introduces form in the Physics, his preferred example is a person who changes from being uneducated to being educated. In this case, the forms are the uneducatedness or educatedness, while the matter is the person that persists through the change. Surely he does not intend for us to think of the person as an element, that their [un]educatedness somehow structures — this would stretch these words so much as to empty them of meaning.

A better way of thinking about form and matter is as two mutually intelligible notions that work together in the constitution of material things.2 Matter is a substratum that of itself is indeterminate between various alternatives, while form is the determination of that substratum to one of those alternatives. So, the matter and form of a thing do not exist separately from one another, but each exists indirectly through the existence of the thing they compose. The form and matter of a human exist where I am, for example, because I am a human composed of form and matter. In Aristotle’s example, when we consider a person apart from whether they are educated or not, we have something that is indeterminate between different levels of being educated, that is we have matter. And adding in the educatedness determines this matter to one of these various alternatives. Or consider another case of form and matter that doesn’t involve structure. Imagine Alice’s hand is moving into Bob’s face. By itself, this motion is indeterminate between (a) Alice attacking Bob and (b) her clumsily hitting him by mistake in the course of reaching to something near him. The form that determines which of these is the case is her intention. Together the motion (as matter) and the intention (as form) constitute her action.

So, form is not structure. But neither are the two entirely separate: if some T exists at least partially by virtue of an underlying structure, then a form determining matter to be a T will need to include that structure. Take as an example a simple wooden table with four legs and a tabletop. The structure places the tabletop above the four legs, each of which is standing upright. And the form and matter? The matter could be the wood itself, in which case the form would be everything that makes the wood a table, including the division of it into pieces, the structuring of these pieces, and the collective intentions we have that make something a table rather than something else like a chair or mug.

Let’s use a water molecule as a case study. Structurally, it arises from a bond between two hydrogen atoms and one oxygen atom, the bond being the structure and the atoms being the elements. In terms of form and matter, things are more complicated. Assuming the water molecule is a substance,3 we’re primarily interested in substantial form and prime matter. Prime matter underlies all material substances and is completely indeterminate, while substantial form determines this matter to being a particular kind of material substance. Mapping this onto language about structure, it is clear that the hydrogen and oxygen atoms are not primary matter, for they are also made up of structured elements: a hydrogen atom, for instance, is made up of a proton and an electron. And these are also made up of structured element: a proton, for instance, is made up of an up quark and a down quark. Since structure is a kind of determination, the prime matter of the water molecule must underly all of these things. Accordingly, the substantial form of the water molecule must include all of these structures at different levels as part of its determination of the prime matter. I have illustrated how these different components all fit together in the following diagram:

form-vs-configuration

What may have initially seemed like a subtle distinction has now snowballed in two clearly different accounts of something as simple as a water molecule. And, moreover, this difference sheds some light on a puzzling claim in Thomistic metaphysics, that the hydrogen and oxygen atoms exist virtually within the water molecule. Only if the water molecule were to be destroyed, leaving free hydrogen and oxygen atoms, then they would really exist. Understandably, someone not familiar with these terms would find this all a little perplexing: the molecules have the same structure both when inside the water and when free, so why say that they only virtually exist in the one case?

For starters, we must note that by calling something “virtual” we are not denying that it has some measure of existence in reality. This might what we colloquially mean by “virtual”, but in Thomism both “real” and “virtual” afford some kind of existence in reality. If we wanted to say that something had no existence in reality, then we’d say that its existence was purely logical.4

Furthermore, when Thomists speak about the way a thing exists, we primarily have in mind its form and matter rather than simply the structures that underly it. And we think that every substance has exactly one substantial form, since a material substance is the determination of matter, not a pre-existing material substance.

Now, while there may be no structural difference between a bound hydrogen atom and a free one, in terms of form and matter there is a substantial difference (pun intended). The bound hydrogen atom exists and is structured as part of the water molecule’s form, whereas the free hydrogen atom exists and is structured by its own form. The free hydrogen atom’s form excludes all sorts of things that are included by the water molecule’s form, not least of which are the structures of the oxygen atoms . Of course, the two are not completely unrelated, since the form of the water molecule in some sense “contains” the form of the hydrogen atom. This is what we’re getting at when we say that the hydrogen exists virtually within the water — even though the water molecule has only one substantial form, its form is multi-faceted.5 It’s because of this that if we destroyed the molecule properly, we could recover the three atoms which until then would have existed virtually within it.


  1. By “structure” I mean a static or dynamic specification of the quantitative relationships between a collection of elements. In my post on the threefold whole I used the word “configuration” instead, but I think “structure” is more familiar to people and so have used it here.
  2. By “things” I include material composites in general, such as substances, accidents, actions, states of affairs, and aggregates.
  3. See Eleonore Stump’s paper “Emergence, Causal Powers, and Aristotelianism in Metaphysics” in Powers and Capacities in Philosophy: The New Aristotelianism. There is a more general question about whether we should consider each individual molecule as a substance, or whether bodies of water are better candidates. This is hugely relevant to us here, and we use the molecule because it’s easier to talk about.
  4. See my post on the real distinction for a discussion on real, virtual, and purely logical in the context of distinctions, which bears some resemblance to how they work in the context of existence.
  5. In order to better understand the multi-faceted nature of forms, we need to consider them as potential wholes. I have discussed these in my post on the threefold whole.

Summary of the book of Job

Below is a summary of the dialogue in Job that I put together as part of working through the book. The book is long, and the purpose of this was to capture the gist of what each person was saying so that I could get a handle on what they were arguing.

The story starts with Job having everything taken away from him and being stricken by disease despite his being a righteous person. He is greatly distressed by this, and as a result wishes that his life would just end so that he need not have to continue struggling through this unwarranted treatment from God. Throughout the dialogue he maintains that he is righteous and that this suffering cannot be the punishment for his wickedness, leading him to question why God would inflict it upon him.

His three friends, Eliphaz, Bildad, and Zophar try to comfort him by explaining why God would have brought such calamity to him, but their attempts all presume too simplistic a model of how God governs the world. Towards the end, Elihu comes and rebukes the three friends for being incapable of upholding the righteousness of God in the face of Job’s complaints. Unlike the other three, Job does not respond to Elihu and God does not reprimand him (42:7–9). This suggests that he is on the right track.

Eliphaz believes that God blesses the pious, and so urges Job to stop wishing his life away and to praise God rather than blame him, so that he can reap blessing. As the dialogue progresses it becomes apparent that he does assume Job has done something wrong, but his primary concern is with what Job does next in order to become blessed.

Bildad believes that God judges the wicked and rewards the righteous, and so urges Job to turn to God in righteousness rather than wish the fate of the wicked upon himself. From his point of view, Job’s family must have been judged for their wickedness and Job is doing himself no favor by wishing this same fate upon himself. He does not think Job is necessarily being judged, but that he should definitely stop asking for it.

Zophar believes that God only judges us because of our wickedness, and that since Job is being judged he must be keeping some sin of his secret. He urges Job to confess and move on, so that he can be right with God again and be done with his punishment.

Elihu believes that God works in ways that we might not expect because he is not a mere human. He judges the wicked and blesses the righteous, sure, but he could also bring calamity to the righteous in order to keep them from falling into wickedness. It’s not like God owes it to us to give us blessing all the time, and ultimately whether we’re righteous or wicked depends on how we respond to suffering. So he criticizes Job for having become a scoffer in response to his suffering, the exact opposite of what he should have done.


(1–2) Job is righteous and God is proud of him. One of the members of the divine court challenge him, saying that Job is only righteous because God has blessed him, and that were Job to suffer he would reject God. God permits him to cause suffering to Job, so long as he doesn’t kill him.

Job (3): I wish I’d never been born, and am amazed that life is given to someone in such misery.

Eliphaz (4–5): You, who comforted others, do you not see that God will bring prosperity to the innocent? Only the evil will perish in their ways, so wishing this upon yourself is wrongheaded. Accept your troubles, and look to God for relief rather than wishing death upon yourself.

Job (6–7): My complaint stands! I have sought God and yet gotten punished severely. Therefore I will continue to despise my troubles.

Bildad (8): How long will you speak like this? God judges the wicked and the righteous according to their deeds. If your children died because of their sin do not join them in cursing God because of it. Rather, be righteous and find prosperity!

Job (9–10): How might I plead my case to this God, who wounds me in spite of my perfection? If in putting off my sorrows I get punished anyway, then what point is there in doing so? As it is, I’m afraid of him and don’t think he’ll stop judging me even if I repent. There is no mediator between us, who can hold his rod back. All I want is for this God, who takes pleasure in punishing his creation, to give me relief for the short time before I fade into nothingness.

Zophar (11): It will do you no good to hide things from God, for he knows all. Repent without holding on to sin secretly and your ailment will be remedied.

Job (12:1–13:12): Am I inferior to you so that I don’t know these things as well? I have seen that God brings both good and evil, and you lie when you say it is otherwise. Would you lie in defense of God? I know that I am righteous, so I will continue in my complaint. If there were someone to show me wrong, then I’d happily admit defeat.

Job to God (13:13–14:22): So then, I ask two things. Withdraw your hand from me that I might not fear to come near, and tell me of my sin. You know that man is limited, and that unlike the tree he has no hope. The tree will sprout again after its death, but not so for man. He remains dead until the end of the heavens. Please, kill me and hide me in Sheol, that I might be hidden from this scourge of life. Oh that the day would come when you honor your creation, but as it is you wear him down and destroy his hope.

Eliphaz (15): We are not to be ignored, for we have the wisdom of our fathers from long ago. You turn away from devotion to God to your own demise. How can you speak of righteousness when not even his heavens are righteous? The man who acts arrogantly toward God is to be afraid of him, and it is better for him not to trust in himself! Do not describe yourself in these terms.

Job (16–17): So much for being my friends! You have given me no comfort in my day of difficulty. God has smitten me and broken me into pieces, and everyone has turned against me. Not only this, but he has made my friends incapable of understanding what is happening. My life is over and my hope is dashed. If I have already turned to desire Sheol then what hope is there left for me to hope in?

Bildad (18): Do not treat us like idiots. Consider this, and then we can talk: surely you are wishing the outcome of the wicked upon yourself[, you who say you are righteous].

Job (19): How long will you attack me with your words, by disgracing me [who is righteous]? God has already disgraced me in every way, and more I my intimate friends have turned on me. Have mercy on me, for God has already stricken me. Know that you who attack me will reap judgement for it, from God my redeemer.

Zophar (20): Why do you insult us with your harsh criticism (censure)? You know from old that the exaltation of the wicked is short-lived. For the evil he holds on to destroys himself, and his insatiable desire is finally fulfilled by God’s judgement upon him. Then the heavens will reveal his iniquity.

Job (21): Hear me out, and then you can continue mocking me. Look at me — am I not appalling to you? Now look at the wicked. They live long and prosper, they are glad and rejoice, they scoff at God and the die peacefully. Clearly I am not being led by them! How often are they really punished, as you say? Are living under a rock?! Who can teach God? He judges everyone. And we see the same overcome the prosperous and the poor. Now I know that you scene against me, because you ask me to reveal to my sin, but have you looked around? The wicked prosper, and others follow them[, quite unlike my situation, so you must be picking on me]! Your words are nothing.

Eliphaz (22): Is it any gain to God if you are blameless? Is he judging you for fearing him? Surely not, it’s because you are wicked. You have done evil, and so God punishes you. You mock God, saying that he’s too far away to know how to run the world[, letting the wicked prosper]. Turn back to God and He will establish you. Lift your face to him, and he will deliver even the one who is not innocent.

Job (23–24): If I stood before God and pleaded my case, then he would judge me righteous. But I cannot find him to do so. I have kept his ways but there is no way for me to change what he has planned for me, and so I dread him. Why doesn’t God judge the wicked on schedule? They do so much evil — worse than what you claim I’ve done — and their victims have nothing, they tread the winepresses but suffer thirst. You say the wicked are judged quickly, yet it seems to me that God prolongs their lives. Please, prove me wrong!

Bildad (25): Listen, God is above all and has armies beyond measure. How could any man be right before him? Even the stars are dim in his eyes, man is a but maggot to him.

Job (26): Wow, so helpful! God is too big to be put into such a simple box!

Job (27): With God as my witness I will not lie by agreeing with all of you. I am righteous and will not make myself wicked by deceit. For what hope is there for the wicked? He does not die quickly, but eventually he or his children reap what he has sown.

Job (28): In searching out gold and silver man has gone places that beasts could not discover, but he has not found wisdom there. Nor can he buy it with gold or silver he made. The birds above have not seen it, nor can anything in the land of the living. Even Death and Abaddon have heard only rumors of it. God however, has seen it and understands the ways to it. For he looks to the ends of the earth and sees everything under the heavens. He’s told man that’s it the fear of God which is wisdom.

Job (29–31): I’ve walked the way of the righteous, for those near me and for strangers. People honored me and thought me a friend of God. But now they laugh at me and turn against me. Didn’t I help the oppressed? But now that I’m oppressed there is no help for me. If I have done any evil then let God cast me down. But I’m righteous! Tell me what my fault is, let my adversary write down the indictment.

Elihu (32): I am young and so I’ve been waiting for wisdom to be revealed by my elders. But behold, you have found no answer to Job! Surely it is not age that gives wisdom but the spirit God gives us, thus I can no longer hold in my opinion on the matter, and flatter my fellow humans by listening to them.

Elihu (33): Job, listen to me, your fellow human who has heard what you’ve been saying. You have said that God is unjustly against you, but you are wrong to complain at him, claiming that he does not hear your cries. God is no mere man like you and I, and he speaks to us in ways that we might at first not notice. In a dream, perhaps, he might terrify us in order to turn us away from pride. In our pain he might rebuke us, that we might be saved from a path leading to death. He does all sorts of things that we may know that he is the source of life.

Elihu (34): You men of understanding, Job has complained about God doing him injustice and thereby numbered himself among the scoffers. Far be it from God, the Judge of everything, that he should do wickedness — no-one has given him this role [that he might fail in it]. Quite the opposite: he calls kings nothing and noblemen wicked! Furthermore, he knows all and does not need anyone to being their case before him. He judges all according to how it really is, and Job has made himself wicked by presuming otherwise [in response to his suffering].

Elihu (35): Job, do you really think you righteousness entitles you to anything before God [so that he couldn’t use affliction for more than judgement]? If you sin, do you affect him? And likewise if you do right? These things only affect your fellow humans. When people cry to God out of selfish ambition rather than awe for God, their cries are empty and God does not answer. So too, Job, your cries are empty because you speak without understanding.

Elihu (36–37): Let me speak of the righteousness of God, with knowledge that is [apparently] far from this place. God does not despise anyone: he helps the afflicted and destroys the wicked. The godless hold onto their anger when faced with difficulty, but for others learn from their affliction and grow from it. You must not be so quick to turn to wrath, which then becomes scoffing. God is a great and powerful teacher, and you must remember to extol his work [rather than fall into resentment]. Just look at all the complex ways in which nature works — that’s him! We know not how he orchestrates anything, for he is so high and mighty, something it would be good for you to keep in mind. “Therefore men fear him; he does not regard any who are wise in their own conceit.”

God (38:1–40:2): Who is speaking without knowledge, confusing the matter? Get ready Job, because I’m going to question you now [as you asked]. Tell me, where were you when I built everything you see? Have you been to the gates of death itself? Do you order the sea, the clouds, light and darkness? Who is it that gives wisdom and takes it away? Is it by your understanding that all animals move and live? You who wish to argue with God, give me an answer.

Job (40:3–5): How can I answer? I am nothing [compared to you]. I have spoken, but I dare not say any more.

God (40:6–41:34): Well, get ready, because I will question you further. Will you condemn me in order to establish yourself in the right? Do you think you are more fit to be the Judge? If so, then in your anger go — destroy all the wicked, let’s see you do it. On the day you do it I will acknowledge that you don’t need me. [But you can’t!] Consider the Behemoth and the Leviathan: even these beasts cause you to tremble, and I made them!

Job (42:1–6): I see that you are above all things. I was rash to dean your present so that I could tell you off, but I see now that I did so out of ignorance. I had only heard about you before, but now I see you with my eyes, and “therefore I despise myself and repent in dust and ashes.”

(42:7–17) Eliphaz, Bildad, and Zophar are reprimanded by God: “My anger burns against [you three] for you have not spoken of me what is right, as my servant Job has.” (42:7) God commands them to offer burnt offerings, and ask Job to pray for them, that God might forgive them. Then God restores Job’s fortunes and eventually “Job died, an old man, and full of days.” (42:17)

Through the law I died to the law

I was recently listening to a sermon on Galatians, and the following statement by Paul caught my eye:

For through the law I died to the law, so that I might live to God. (2:19)

This got me thinking that the law might have a more important role in salvation history than I had previously considered. To see what I mean, consider the ways that the law is related to sin. First, the law teaches us about sin, helping us to understand it for what it is. Second, the law condemns sin as disobedience against God. We see both of these, for instance, in what Paul says elsewhere:

Now we know that whatever the law says it speaks to those who are under the law, so that every mouth may be stopped, and the whole world may be held accountable to God. For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin. (Rom 3:19–20)

This statement from Galatians suggested to me that we should consider adding a third item to this list: what if the law also provides the means by which sin and death could be escaped? I don’t mean this in the sense that by living under the law we could somehow escape sin and death — we know that this is only possible through Christ. What I’m suggesting is that the law provided the mechanism that Christ leveraged in order to rescue us from sin and death.

The law as a means of escape from sin

In order to see how this works, we need to briefly remind ourselves of the story of sin, death, and the law. This is most clearly unpacked in Romans 5–7, but it also underlies the much shorter treatment in Galatians 3. In Romans 5, Paul introduces the story like this:

Therefore, just as sin came into the world through one man, and death through sin, and so death spread to all men because all sinned — for sin indeed was in the world before the law was given, but sin is not counted where there is no law. Yet death reigned from Adam to Moses, even over those whose sinning was not like the transgression of Adam, who was a type of the one who was to come. (Rom 5:12–14)

As he begins comparing Adam and Jesus, Paul interrupts himself to make sure we’re all on the same page. “Sin was in the world, you understand, long before the law was given, but it not was reckoned to anyone before there was a law. And yet, even though people were not sinning in ways reckoned by a law (as with Adam, who had been given an explicit command) they were nevertheless dying.” Sin and death reign even though sin is not being counted by the law, which is a huge problem. Counted or not, sin is contrary to God’s created order — it corrupts us and goes against our flourishing (Rom 3:23), and it produces death in us (Rom 2:12–16). But without some kind of reckoning, this corruption is nebulous and intractable: it’s not a “thing” that we can contain (or count), but just an indiscernible corrosive power within God’s good creation. How do you begin to address sin when it’s concealed like this? How could you forgive it without it first being reckoned? How do you cleanse it without it first being counted?

You can’t. Using different imagery, without some reckoning sin was free to roam around in the darkness and wreak devastation without any way to handle it. So, God introduced a law that covered all of sin, rather than just the single command given to Adam. How does this help? Paul gives us two answers, one in Romans and one in Galatians. In Romans, he notes that a law is escapable through death:

Or do you not know, brothers — for I am speaking to those who know the law — that the law is binding on a person only as long as he lives? For a married woman is bound by law to her husband while he lives, but if her husband dies she is released from the law of marriage. Accordingly, she will be called an adulteress if she lives with another man while her husband is alive. But if her husband dies, she is free from that law, and if she marries another man she is not an adulteress. (Rom 7:1–3)

And as he had argued earlier, we who trust in Christ have died with him (Rom 6:1–14), and are therefore released from the law:

Likewise, my brothers, you also have died to the law through the body of Christ, so that you may belong to another, to him who has been raised from the dead, in order that we may bear fruit for God. For while we were living in the flesh, our sinful passions, aroused by the law, were at work in our members to bear fruit for death. But now we are released from the law, having died to that which held us captive, so that we serve in the new way of the Spirit and not in the old way of the written code. (Rom 7:4–6)

So, before the law sin was an intractable corruption, but once sin is covered by a law we have a means by which to escape it, namely death. Put another way, before the law death was just a consequence of sin, but with the law it becomes the means of escaping it. Of course, it’s not a means for us to take hold of ourselves. Instead, the law makes Christ’s death, in which we share, capable of releasing us from sin.

In Galatians, Paul uses the notion of a curse to explain the same thing. On this account, the law curses anyone who does not obey it, and Christ became a curse for us so that we might be redeemed from the law, and the sin that it condemned:

For all who rely on works of the law are under a curse; for it is written, “Cursed be everyone who does not abide by all things written in the Book of the Law, and do them.” Now it is evident that no one is justified before God by the law, for “The righteous shall live by faith.” But the law is not of faith, rather “The one who does them shall live by them.” Christ redeemed us from the curse of the law by becoming a curse for us — for it is written, “Cursed is everyone who is hanged on a tree” — so that in Christ Jesus the blessing of Abraham might come to the Gentiles, so that we might receive the promised Spirit through faith. (Gal 3:10–14)

So, the law curses our sinfulness, allowing Christ to become a curse for us and thereby redeem us.

In both cases, then, we might say that the law introduces the “middle term” that connects our sin to Christ’s redeeming work, such that that which was nebulous and inescapable becomes concrete and escapable — granted, of course, that we have Christ to achieve this escape for us. The law circumscribes sin and provides the means of escaping it, so that through the law I may die to the law and thereby escape sin. Again, we must underscore the fact that this is not achieved by me directly, but in my sharing in Christ’s death. The law does not provide a means by which I can release myself from sin, but a means by which Christ can redeem me and secure my escape from sin.

Comparing this to some other things Paul says

Having outlined this third relationship between sin and the law, it would be good to comment briefly on two other things Paul has to say, one in Romans and one in Galatians.

In Romans, Paul says that sin produces death in us through the law (7:13), but I’ve said that death was a consequence of sin before the law. Well, in fact it is not I who said this, but Paul himself. He is clear that even without the law we will die and be judged (Rom 2:12–16), and that before there was a law to count it people died because of their sin (5:12–14). Paul’s statement in Rom 7:13 appears in the context of a train of thought that began earlier with these words:

… if it had not been for the law, I would not have known sin. For I would not have known what it is to covet if the law had not said, “You shall not covet.” (Rom 7:7)

Even though sin can produce death in us without the law, it is only that sin that can be known as such from creation (Rom 1:18–32). There will be other sin that cannot be known in this way — Paul uses the example of coveting — so that when the law comes and condemns all sin it includes these sins as well. It seems that in Rom 7 Paul is talking with reference to these, or at least with reference to the increased responsibility that comes with the disclosure of the law.

Turning to Galatians, Paul says that the law “was added because of transgressions” (Gal 3:19), and then goes on to say the following:

Now before faith came, we were held captive under the law, imprisoned until the coming faith would be revealed. So then, the law was our guardian until Christ came, in order that we might be justified by faith. But now that faith has come, we are no longer under a guardian, for in Christ Jesus you are all sons of God, through faith. (Gal 3:23–26)

Now, I think these statements can be coherently interpreted in terms of the first two ways the law relates to sin (making it known, and condemning it), but the third way we’ve considered in this post develops this picture nicely. As we’ve been saying, the law was added in order to circumscribe sin in anticipation of the day when Christ would come and open up the way to escape it through his death under the law.

God, matter, and necessary existence

Reader Ante asks the following question in the comments of my response to his previous question:

The issue I have is with regards to God’s necessary existence. Since God’s essence and existence are identical, He exists necessarily. But the same thing could be said of matter as well, as it seems to me. Why could it not be the case that some fundamental layer of physical reality necessarily exists aka that it cannot fail to exist? Suppose that we are dealing with some form of “atomism”. How do we know that some kind of physical particles or fields don’t have necessary existence? Existence could be a PART of particles/fields or some other kind of fundamental physical reality. Then, what it means to be a particle/field ENTAILS, among other things, that this particle/field EXISTS.

In fact, there are three related questions in here. Here we’ll try to disentangle them from one another, and give a brief answer to each.

Q1. Does matter have necessary existence?

Without trying to sound facetious, it depends on what you mean by “matter,” “necessary,” and “existence.”

Starting with matter, there are at least three senses that it can have. In contemporary usage, matter refers to the “stuff” that underlies physical reality — atoms, electrons, quarks, bosons, and so on. Then there is matter in the Aristotelian sense, which comes in two varieties, namely primary and secondary matter. Unlike the contemporary “physical” matter, the Aristotelian “metaphysical” matter is never a thing of itself, but is always a constitutive principle of things. It composes with form to, well, form composite things, such as animals, people, actions, and aggregates.

In general, this composition works as follows: matter is a substratum that of itself is indeterminate between various alternatives, while form is the determination of that substratum to one of those alternatives. So, the matter and form of a thing do not exist separately from one another, but each exists indirectly through the existence of the thing they compose. The form and matter of a human exist where I am, for example, because I am a human composed of form and matter. When a thing changes it switches one form for another, but retains the same underlying matter. When a thing changes without being destroyed, like me standing up or changing clothes, then we’re talking about secondary matter composed with accidental form. But when the change brings about the destruction of one thing and the beginning of another thing, as when I die and become a corpse, then we’re talking about primary matter and substantial form. Primary matter is therefore more fundamental than secondary matter, and in some sense it persists across all change, even though whenever it exists it does so indirectly through the things it composes.

With necessary existence there is also a distinction between contemporary usage and classical usage. In contemporary metaphysics, “necessary” and “contingent” are cashed out in terms of possible worlds: a thing has necessary existence if it exists in every possible world, and has contingent existence if it fails to exist in some possible worlds. Since possible worlds capture what could have been the case, a thing exists necessarily if it could not have been the case that it failed to exist, while it exists contingently if it could have been the case that it failed to exist.

When Aquinas refers to things as necessary and contingent, however, he has something quite different in mind. He is not talking about whether things may or may not exist in other possible worlds, but whether things are corruptible or not — whether they go in and out of existence — in this possible world. For him, the corruptibility of something is a consequence of its nature: material things are made up of these two principles which need not be composed (form and matter), and therefore they are corruptible. Angels and God, on the other hand, are incorruptible. For the sake of clarity, then, we will refer to the necessary existence of Aquinas as “incorruptibility” and the necessary existence of contemporary metaphysics as “metaphysical necessity.”

In order to understand how a Thomist would approach the question of metaphysical necessity, we can compare it to a position defended by some in contemporary metaphysics, called “modal essentialism.” Broadly speaking, modal essentialists seek to analyze the notion of “essence” in terms of facts about possible worlds: the essence of a thing is the collection of its essential properties, and a property of a thing is essential if that thing has that property in every possible world it exists. Thomists, by contrast, hold to a position that has been called “real essentialism,” where essences are fundamental to things, and the truths about possible worlds are grounded in them rather than the other way around.1 Thus, from our point of view, modal essentialism gets things backwards.

An important consequence of real essentialism is that it allows essences to govern whether something is metaphysically necessary or not. For the Thomist, the essence of every thing apart from God is really distinct from its existence, with the former being a potential of some kind and the latter being its continued actualization. Now, every potential depends on another actuality for its continued actualization, and every chain of actualized potentials eventually leads back to God. Furthermore, since God is a free agent, it is metaphysically contingent whether he chooses to actualize any potentials at all, and therefore it is a metaphysically contingent fact that anything other than himself exists from moment to moment. God is the only exemption from this, because he does not exist through the actualization of a potential — he is pure actuality, his essence is his existence. Thus, God is metaphysically necessary while everything else is metaphysically contingent.

Returning to the two kinds of matter, every material thing exists through the actualization of a potential. Since contemporary matter is a material thing it is therefore metaphysically contingent along with every other material thing. Aristotelian matter, as we have said, exists at any moment indirectly through the existence of the material thing it makes up, and therefore will also be metaphysically contingent.

But they are not in the same boat when it comes to corruptibility. Contemporary matter is corruptible, since like any material thing it comes in and goes out of existence. Likewise, Aristotelian secondary matter comes in and goes out of existence along with the substances to which it belongs. But since Aristotelian primary matter persists through all generation and corruption, it is in some sense never generated or corrupted itself, and is therefore in that sense incorruptible. Of course, it is incorruptible in the thinnest sense. Even though it always exists, at any given moment it only exists indirectly through the substances it composes. And so, it would go out of existence the moment God stopped sustaining all material things in existence.

Indeed, primary matter might be the first incorruptible thing arrived at in Aquinas’s Third Way. At a crucial point in the argument, which has generated much discussion, he says, “if everything is corruptible, then at one time there could have been nothing in existence.” On the face of it, this sounds like he’s committing the quantifier shift fallacy. And this might be the case if he was only quantifying over substances, but if he was quantifying over substances and their principles then this shift is quite reasonable. If primary matter is also corruptible, then it also wouldn’t have existed at some time in the past. But since, for Aquinas, generation depends on pre-existing matter, it would follow that nothing could have subsequently been generated, which is contrary to experience. This leads him to posit the first incorruptible thing in his chain of incorruptible things, namely primary matter, from which point he traces the chain all the way back to God, the only incorruptible thing that is also metaphysically necessary.

So, does matter have necessary existence? In some sense yes, but mostly no:

Contemporary matter Primary matter Secondary matter
Metaphysically necessary No No No
Incorruptible No Yes No

Q2. What if atomism were true?

Would our answer change if some form of atomism were true? In this case, there would presumably be a bunch of fundamental physical things called “atoms,” which would not come in or go out of existence. This would certainly make them incorruptible, like Aristotelian primary matter, but would it make them metaphysically necessary?

It’s tempting to reach for our earlier answer about primary matter and apply it to these atoms, but that would be a mistake. For that answer, it was crucial that primary matter is a principle of things rather than a thing of itself. Because of this, its existence at any moment is in some sense parasitic on the composite thing to which it belongs, and if God simply stopped sustaining all composite things in existence, then primary matter would disappear along with them. By contrast, these atoms are not principles, but things in their own right, so the same line of argumentation won’t work.

A better analogy would be the angels. They are incorruptible, since they are not made out of matter at all, but their essence is nevertheless really distinct from their existence, which means they exist through the continued actualization of a potential, and therefore depend on God for their continued existence. So, what reason could there be for thinking that these atoms would need to likewise exist through the continued actualization of potentials?

For one thing, they are material, and therefore exist through the actualization of potentials of primary matter like any other material thing. What makes them different from other material things is not that this doesn’t apply to them, but rather that this applies to them without them being generated or corrupted.

For another thing, we saw earlier that anything whose essence is not identical to its existence is metaphysically contingent, and there can be only one being whose essence is identical with their existence. I covered this in a previous post on the real distinction, but briefly: existence unifies all existing things as existing, whereas essence diversifies us within this unity by limiting that existence in various ways. One thing is distinct from another by virtue of being limited in a way that the other is not. Material things with the same common essence are diversified by differing determinate dimensions, which limit us to different places and times; created immaterial substances (angels) are diversified simply by their individual essences, so that there are no two angels have their existence limited in a common way; and God is that existence which is not limited in any way by his essence, since they are identical. Since diversity occurs through limitation, and since a thing whose essence is identical to its existence is not limited, there cannot be a diversity of such things.

Q3. Could existence be part of an essence without being identical to it?

But what if the existence of these atoms was really distinct but not wholly distinct from their essences? That is, why couldn’t their existence be a proper part of their essence?

Let’s start by considering some things which are parts of essences: substantial form and primary matter. When we first learn about form and matter, they are said to correspond to actuality and potentiality — the indeterminacy of matter corresponds to its potential for being in different ways, and the determination of this matter by the form is an actualization of one of those potentials. But things get a little confusing, later, when we then learn that both form and matter are parts of an essence, and that essence is a sort of potentiality for existence. How is it possible that form is an actuality but part of a potentiality?

Fundamentally, this boils down to the fact that the form-matter distinction is orthogonal to the essence-existence distinction. In a composite being, there are these two overlapping real distinctions, each of which focuses on the actualization of a potential in different but complementary ways. The form-matter distinction captures what obtains when a material thing exists, while the essence-existence distinction captures whether this obtains in reality. Form accounts for the unity a material thing has with all other material things of the same kind, and matter distinguishes this instance of the kind from that instance of the kind. Existence accounts for the unity a thing has with all existing things, and essence distinguishes this existing thing from that existing thing.

form-matter-vs-essence-existence

To put this in more concrete terms, we can compare me, Sherlock Holmes, and the tree outside my house. Many people don’t know this about me, but I’m a composite of form and matter.2 Likewise, the tree is a composite of form and matter, although my form makes me a human while the tree’s form makes it a tree. Sherlock Holmes is also a composite of form and matter, since this is part of being a human, and he would have the same sort of form that I do. Now, in one sense I am more similar to Sherlock Holmes than to the tree, but in another sense I am more similar to the tree than to Sherlock Holmes. The difference lies in whether we consider things in terms of their form and matter, or in terms of their essence and existence: I am similar to Sherlock Holmes in virtue of our shared form which the tree does not have, and I am similar to the tree in virtue of our shared existence which Sherlock Holmes does not have.

The Sherlock Holmes case also lets us see how the actuality of form can be part of the potentiality of essence. Consider this question: does Sherlock Holmes’s substantial form actualize a potential in his primary matter? Well, in one sense of course it does, for if it didn’t then he wouldn’t be a human capable of sleuthing around London. But in another sense of course it does not, for if it did then he would be a real human rather than a fictional character. It’s the difference between these two senses that is captured by the actualization of an essence by its existence — form is always the actualization a potential of matter, but it’s when this actualization obtains in reality that this corresponds to the actualization of something’s essence by its existence.

Since the actualization of matter by form is what constitutes the existence of a composite thing, and since this actualization is contained in the essence of a thing, we could in some sense say that the “existence” of a thing is contained in its essence. But, as we’ve just seen, this will not help in the present case, because this doesn’t determine one way or the other whether the thing’s existence obtains in reality. The core of the problem is that an essence, of itself, is indifferent to whether it obtains in reality or not, which is why we can talk of the essence of Sherlock Holmes without falling into incoherence. This is the indifference that I’ve recently noted belongs to all potentials, and it is on account of this that we say essence is a potential.

But why couldn’t the existence which is the actualization of the essence (and accounts for it obtaining in reality) be a proper part of that essence? Because this would entail that the essence is capable of having multiple simultaneous existences, which is absurd. To see this, let A be the part of the essence which is also the thing’s existence and let B be the other part (or the collection of other parts). From this it follows that A is an actuality since existence is a sort of actuality, and B is a potentiality since it is the part of the thing’s essence that is not its existence. In order for B to exist, then, it would need to be actualized. The resulting actuality, call it A2, would need to be separate from A. Why? Because, as we’ve seen in our above discussions on the essence-existence and form-matter distinctions, actualities are distinguished from one another by reference to the potentials they are the actualizations of (or, in the special case, because one is an actualized potential and the other is a pure actuality). So, since A is not the actualization of B but A2 is, it follows that A and A2 are distinct actualities. But since A is stipulated to be the existence of the thing, and since A2 is the actualization of the essence of the thing, it follows that A and A2 are distinct existences of the same thing.

In fact, a parallel argument could be raised against any proposal that seeks to divide an essence into parts, whether they all be actualities, all potentials, or a mixture of the two. An essence must be a single potential or actuality. It might have parts in the sense we were considering earlier, but these are not parts in the sense we’re talking about now. That is, an essence can have parts in the sense that it is the potential for the existence of a composite thing, not in the sense that it itself is a composite thing.

Conclusion and further reading

In the course of these answers we’ve had to go through some pretty heavy Aristotelian metaphysics, hitting all the important distinctions and clarifying them as we go. Of course so much more can and has been said about each one, but I can’t hope to cover all of that in one blog post. So, Ante, I hope what I’ve said has at least helped you along the way a bit.


  1. Non-Thomist contemporary philosophers have also taken exception to the modal essentialist proposal. See, for instance, Kit Fine’s “Essence and Modality.” For longer discussions on these issues, see Ross Inman’s Substantial Priority and David Oderberg’s Real Essentialism.
  2. It’s funny because it’s true: the vast majority of the human population is not interested in philosophy and would have no idea what it even means to be a form-matter composite. Nor, as my housemate notes, does the vast majority of the human race know me at all.

Monty Hall explained in two sentences

Since the host will never open a door with the car behind it, the remaining door will have a car behind it in exactly those cases where you originally pick a door with a goat behind it. Since there is a 2/3 chance of you originally picking a door with a goat behind it, there is therefore a 2/3 chance that the remaining door has a car behind it.

If you don’t know what I’m talking about, you can find the Month Hall problem described in the movie 21 or the TV show Brooklyn Nine-Nine. You can find longer explanations of it over at D!NG, Vox, and Numberphile.

Potentiality and inertia

A key thing to appreciate about potentials is that they are indifferent to what is actually the case. It’s because of this that they are able to play the role they do in accounting for the reality of change, together with actualities.

I have the potential to sit down even when I am standing up, and it is this potential that I actualize when I do eventually sit down. If I did not have that potential, then I would not be able to actualize it in myself and therefore not be able to sit down. We can see this work itself in cases where things lack the relevant potentials: a rock depends on other things to move it because it does not have the potential for self-movement, a squirrel never actually thinks about the physical laws of the universe because it lacks any potential for rational thought, and a match never produces snow when struck because it does not have any corresponding potential for this.

I also retain the potential to sit down while I’m actually sitting down, since I can’t be actualizing a potential I don’t have. This can be missed because we sometimes speak of the potential to become actual in some way rather than the potential to be actual in some way, even though the latter is more fundamental. This ambiguity is not particularly surprising, since potentials are capacities for being actual in particular ways and we see this ambiguity in other examples of capacities: a one-liter bottle has the capacity for containing one liter of liquid even when full — since that’s exactly what it’s doing — it just doesn’t have the capacity for containing another liter of liquid. Similarly, if I’m currently sitting down I still have my potential to be sitting down, even if it is no longer the case that I can move to the state of sitting down.

Thus, the potential exists in me regardless of whether it is actualized or not, and so, as we said, the potential itself is indifferent to what is actually the case. It follows from this that every potential depends on some other actuality in order to be actualized from moment to moment, and in an indirect way it also depends on some other actuality in order to be unactualized. At any given moment, the existence of a potential cannot guarantee one way or the other what is actually the case — it can only determine what could be, not what is the case. And this can’t be addressed simply by adding another potential into the mix, because that will suffer from the same limitation. Rather, what is needed is an actuality which either actualizes the potential or indirectly unactualizes it by actualizing some other incompatible potential, as sitting down is incompatible with standing up. Of course, this other actuality could itself be an actualized potential, and so on, and so on.

The indifference of potentials is, I think, the core reason for why actualized potentials need to be continually actualized by some other actuality. On the face of it, however, the result that potentials depend on actualities in order to be continually actualized seems to be at odds with the Newtonian principle of inertia. Since inertia is a well-known phenomenon, and since it makes our result counter-intuitive, it’s worth considering this intuition in more detail. Inertia, Newton tells us, “is the power of resisting by which every body, so far as it is able, preserves in its state either of resting or of moving uniformly straight forward.”1 Applying this to the notion of potential we’ve been discussing, we may wonder why a potential needs to be continually actualized by some actuality in order to stay actualized. Making this a bit more precise, consider the following two conditions:

  1. At time t, potential P exists.
  2. At some earlier time t* < t, P was actualized by something else.

A little reflection will make clear that these are not sufficient to account for P’s being actualized at time t. If I was holding a book above the ground in order to actualize its potential to be a meter above the ground at time t*, but have since let it go, then by time t the book would be falling to the ground, and therefore the potential would no longer be actualized. Of course, this occurs because of the gravitational force applied by the earth on the book, and realizing this we might add a third condition to the two above:

  1. At time t, potential P exists.
  2. At some earlier time t* < t, P was actualized by something else.
  3. Between t* and t, nothing actualizes a potential P* that is incompatible with P.

But while this addresses our previous example, this is still insufficient. An example that illustrates this from more recent physics is radioactive decay, wherein an unstable atom will spontaneously emit particles of its own accord, and thereby unactualize certain potentials within itself. More generally, any non-equilibrium state of a system will lead that system to change the set of potentials that are actualized within it as it tends toward an equilibrium state. Both of these involve potentials which are actualized in a way that is inherently temporary when left alone. Once we realize that such “transiently actualized potentials” exist, we recognize this behavior in everyday things around us without needing to defer to such complicated examples. For instance, the clicking of my fingers is an actualization of a potential that inherently becomes unactualized almost immediately. And a burning fire tends to go out as it uses up the combustible molecules in the wood.

You’ll notice, however, that none of these examples mention the motion of physical objects in straight lines. And that’s no coincidence, since inertia applies in those cases. The point of these examples is not to somehow disprove inertia, but rather to show the failure of a certain approach to questions of actuality and potentiality. Inertia is a very specific physical principle, which cannot be applied to such a general metaphysical notion as potentiality. Rather than trying to understand actuality and potentiality in terms of inertia, therefore, we should instead try to understand inertia in terms of actuality and potentiality. In doing so we will see how inertia is in no way at odds with our earlier conclusion about the actualization of potentials.

With this reorientation in hand, we can ask: what needs to be added to our three conditions in order to properly characterize inertial behaviors? We’ve said that a potential of itself is indifferent to what is actual. Since the continued actualization of a potential is not indifferent to what is actual, it follows that we should be looking for an actuality. And not just any actuality, but an actuality that is somehow ordered to maintaining the actualization of P:

  1. At time t, potential P exists.
  2. At some earlier time t* < t, P was actualized by something else.
  3. Between t* and t, nothing actualizes a potential P* that is incompatible with P.
  4. Since t* until t, some actuality A maintains the actualization of P.

Importantly, this actuality doesn’t need to be something external to the thing whose potential we’re considering — as Newton said, inertia is in some sense the power of a body — it just won’t be the potential itself. We could call this actuality the “inertial actuality,” since it is the source of the inertial behavior. At the level of generality that we’re considering it here, inertial behaviors and actualities are not restricted to physical inertia. Just as there are many different ways that actuality and potentiality come to be in the world, so too there may be many different kinds of inertia. Nevertheless, we can characterize inertia in general in terms of another category, and use physical inertia as a paradigm case.

The category I have in mind is the Aristotelian form. Form and matter are two mutually intelligible categories, at least when it comes to material things. Generally speaking, matter is a substratum of some kind that is indeterminate of itself, and form is the determination of that substratum to one of the alternatives.2 In the case of physical things, matter is that which underlies all physical reality, and form is that which determines what kind of thing each physical thing is. It’s because matter is determined in a particular way that some physical things are trees, others are rocks, others sub-atomic particles, and so on. The indeterminacy of matter corresponds to its potential of being in different ways, and the determination of this matter by the form is an actualization of one of those potentials. Thus, a form, as an actuality, is a ready candidate for being an inertial actuality.

And indeed, the Aristotelian notion of form does well in accounting for physical inertia, both in terms of how Newton originally conceived of it (his rejection of the notion notwithstanding), and in terms of how physicists have conceived of it since. On this account, inertia as a feature common to forms of all physical things, as something that flows from the determination of matter regardless of the form that is doing the determination. Not only is form an actuality internal to a thing, but it is also common for forms to only partially determine matter, leaving it up to further forms to complete them. For instance, the primary (or substantial) form of a squirrel determines its underlying matter to be ordered in a certain kind of activity of life, but is indifferent to the exact details of that life, such as location, size, strength, and so on. These variables are provided by the primary form, to be fixed by secondary (or accidental) forms that augment the exact shape of that life at different times. Likewise, in the case of inertia, the primary form of any physical thing orders that thing in such a way as it maintains its rectilinear motion, but is indifferent as to exactly which inertial frame it’s in. This variable is provided by the primary form, but is fixed by other causes, which thereby impart the relevant secondary form of the precise rectilinear motion to be maintained.

Now, Aristotle knew that the primary forms of natural things would move them in the absence of some countervailing influence. His mistake was his particular conception of this motion: he thought that it was always ordered toward a specific place or in a specific direction, with light things inherently moving upward and heavy things inherently moving downward. The inadequacy of this particular conception of physical motion notwithstanding, his broader theory of forms is still a valuable tool in accounting for modern conceptions of physical inertia.

So, the primary forms of physical things are the inertial actualities that account for their physical inertial behavior. Moreover, we can flesh out the picture as follows. Every primary form of a physical thing will be the actualization of a potential in the matter underlying that physical thing. Applying our argument from the indifference of potentials, it follows that this form is actualized by some other actuality. And since this form is what grounds the existence of the physical thing in question, this other actuality must be the actuality of something else. But it’s not as though this cause will be some other perpetually-conjoined physical thing, since physical things only act on other pre-existing physical things, while this cause is sustaining the existence of the physical thing in question from moment to moment. The primary form a physical thing, then, is a metaphysical “threshold” of sorts, beyond which we move from physical actualities to non-physical actualities.

This leads us to another sort of inertia that is discussed in metaphysics, namely existential inertia. This refers to the inherent tendency of things to stay in existence in the absence of countervailing influences. In the terms of what we’ve been discussing, it’s the notion that once a physical thing has been brought into existence, we don’t need a “something else” to keep it in existence. There are, I think, two motivations that might be given for existential inertia, each problematic in their own way. First, we could motivate it by analogy to physical inertia. The problem with this, as we’ve seen above, is that such “inertial explanations” require an inertial actuality, and since we’re considering the actualization of a thing’s potential for existence, this further actuality cannot be something internal to that thing. Second, we could motivate it by generalizing the observation that the things we experience don’t require continually conjoined causes to keep them in existence. The problem with this is that it’s looking for the wrong sort of cause, not realizing that in talking about the cause of a thing’s continual being we’ve crossed that metaphysical threshold we just mentioned. We are not saying that this cause somehow acts on that thing, as if to presume that the thing somehow pre-exists the acting, but rather that by acting the cause actualizes the potential whereby the thing has existence from moment to moment in the first place. If this cause acts “on” anything, it’s on the thing’s constitutive principles, such as its form and matter, not the thing itself.

There is, however, something to be said for a qualified version of existential inertia: insofar as something is determined to exist, it is determined to continue existing. Thus, many things tend to preserve themselves in existence until they’re destroyed, or the underlying resources that they depend on run out. But this flows from the primary form of such things, and so as before if this form is an actualized potential then it will need a cause.

Further reading

If you’re interested in reading more about inertia and related topics, I can recommend Sean Collins’s paper “Animals, Inertia, and the Concept of Force” (or his related blogpost Animals, Inertia, and Projectile motion), Thomas McLaughlin’s paper “Nature and Inertia” (JSTOR), the exchange between Edward Feser and Michael Rota in the Proceedings of the Society for Medieval Logic and Metaphysics (vol 10), and Feser’s blogpost Oerter on inertial motion and angels.


  1. Isaac Newton, The Principia (def 3), cited in Thomas McLaughlin, “Nature and Inertia.”
  2. See my discussion on the threefold whole for an extensive discussion on form and matter. To see that these general definitions extend beyond simple physical objects, consider the following examples. The matter of a wooden table is the underlying wood, since it is indeterminate between various ways of being used, and the form of the table is how the wood is cut up into pieces and structured together in a particular way. The matter of my action of punching something is the motion of my arm, since the same motion is present in different actions, and the form of my action is my intention to damage something. The matter of a person educated in some field is the person considered without regard to their education, and the form is their educatedness or uneducatedness.

Divine simplicity and freedom

In the conversation on divine simplicity over at the Theopolis Institute, Mullins’ most recent response draws attention to the three premises that are “only affirmed by proponents of divine simplicity”:

  1. All of God’s actions are identical to each other such that there is only one divine act.
  2. God’s act to give grace is identical to God’s one divine act.
  3. God’s one divine act is identical to God’s existence.

After which come the following steps:

  1. Therefore, God’s one divine act is absolutely necessary.
  2. If God’s one divine act is absolutely necessary, then God’s act to give grace is absolutely necessary.
  3. Therefore, God’s act to give grace is absolutely necessary.

This implication is problematic for Christians because we hold that God is free to withhold grace if he chooses, which means his act of giving grace cannot be necessary.

But, while proponents of divine simplicity do indeed affirm (9)–(11), we reject (13) and therefore reject the conclusion in (14). In order to see how this works, it would be good to consider a parallel argument involving a more familiar situation. Imagine that whenever Alice is put in some circumstance C she must choose between two options, A and B. Assuming that Alice has libertarian free will, in some possible worlds she will choose A and in other possible worlds she will choose B. Supposing that in the actual world she chooses A, we have the following argument:

  1. Alice’s choice of A is identical to her choice between A and B.
  2. Alice necessarily chooses between A and B in circumstance C.
  3. Therefore Alice necessarily chooses A in circumstance C.

Now, (3) is false on our supposition about Alice’s free will. The problem with this argument is that (1) is ambiguous. If the identity in view is necessary (that is, if “Alice’s choice of A” is a rigid designator for “Alice’s choice between A and B”), then the argument is valid but the premise is obviously false. If, on the other hand, the identity in view is world-relative (that is, if it is just making a claim about the actual world), then the premise is true but the argument is invalid by virtue of committing a modal scope fallacy.

To give a common example of this fallacy, consider the following argument which is a direct parallel of our choice argument:

  1. The number of planets in our solar system is identical to eight.
  2. Eight is necessarily greater than seven.
  3. Therefore the number of planets in our solar system is necessarily greater than seven.

The first premise of this planet argument suffers the same ambiguity and pitfalls as the first premise of the choice argument. The reason for this in the choice argument comes down to the nature of libertarian choice: the same act of choosing can amount in different choices in different worlds.

But there is a subtle and interesting response lurking in the vicinity. In libertarian choices, the response goes, the choice between A and B is a deliberative act which consists in Alice weighing the reasons for preferring A over B up against the reasons for preferring B over A, while the choice of A is the resultant act of Alice pursuing A. Thus, despite initial appearances, the choices are not identical acts, but are two distinct acts, one of which causes the other in a non-deterministic way. In God’s case, however, we have one act rather than two, and so the parallel doesn’t work.

Does such a response rebuff our objection? I don’t think so, for it still grants that there is indeterminism in the deliberative act, which is sufficient for our purposes. With this we can reframe the choice argument as follows:

  1. The act that causes Alice to pursue A is identical to her deliberative act.
  2. Alice necessarily engages in her deliberative act in circumstance C.
  3. Therefore, Alice necessarily engages in the act that causes her to pursue A in circumstance C.

We see here the same problems with the identity in premise (1), despite granting the distinction introduced by the response.

But can we just ignore Alice’s second act of pursuing A? Here we must appreciate an important difference between God’s choices and ours. Alice’s pursuit of A does not belong to her choosing per se, but rather to the execution of the choice she had already made in her deliberative act. Humans need this additional step because our actions find their expression through our bodies — we need to move somewhere, communicate something, start a new thought process, or something else. But God needs no additional act of execution, he acts without need for mediation — he does not need to work through a body and does not depend on other things to bring about his effects. God’s one divine act consists of him choosing which world to actualize based on the the contrastive reasons for preferring each world over the alternatives, including factors such as whether to create anything or not, and whether to give grace or not. This is analogous to Alice’s deliberative act, although without any need for actual deliberation, since God is immediately aware of the all the relevant reasons and does not need to weigh them up successively. And because God is not limited like we are, this one act immediately produces its effects rather than requiring a follow-up act to bring it about.

So, proponents of divine simplicity should reject premise (13) of Mullins’ argument because the identities in premises (9)–(11), while true, are not sufficient to do the work he needs them to do.

Breaking the silence

This year has been very busy for me, and which has unfortunately led this blog to fall by the wayside. Among the things that have been keeping me busy is a new project I’ve started with a friend called Faith Seeking Understanding: a ministry geared towards equipping Christians to develop a biblical worldview, grounded in the Bible as a whole, and integrated with knowledge from God’s creation, to know and serve him better. It seeks to combine my loves for theology and philosophy for the purposes of helping Christians think through their faith more deeply. More info will be available once we get our website up and running.

I’ve also recently given two sermons on Leviticus, titled The Holy and Dangerous God and The Holy and Good Law. The second of these includes part of the research I’ve been doing on the Levitical law and how we as Christians should think about its continuing relevance to us today. I’ll be adding both of these talks to the Leviticus page on this site.

One of the things I’ve been considering ⁠— and may try out in the coming weeks while I’m still busy ⁠— is posting shorter thoughts on things as I come across them. Much of the content on this blog is longer-form, and while it is certainly my preference ⁠this takes much longer to research, write, and edit. Shorter-form posts might therefore be a way to ensure consistent output in times of busyness.

Eternity’s relation to time

A few months ago, reader Ante asked this question on my What I Believe page:

I am very much struggling how to combine a presentist account of time (like the A-theory for example) and the view that God is outside of time, in a Thomistic sense.

I would be very thankful for your help, since it seems to me that I am hitting a wall regarding this issue, since I cannot accept a B-theory of time, but at the same time the view of St. Thomas regarding God’s eternity is much more plausible than the other philosophical alternatives (especially open theism!).

For those unfamiliar with the relevant terms, we begin by briefly explaining what the A-theory and B-theory are, how they relate to presentism, and what this has to do with God’s eternity.

The distinction between A- and B-theory of time was introduced to analytic philosophy by McTaggart in his paper The Unreality of Time. Briefly, the A-theory of time holds that there is some objectively privileged moment of time we call the present, relative to which other moments of time can be categorized into past and future (called the A-series). By saying it is objectively privileged we mean that the fact of which moment is present is not a matter of perspective, but is rather a feature of reality prior to any considerations from us. The B-theory, by contrast, denies that there is such an objectively privileged moment of time, and holds that the only relations between moments are those of earlier than and later than (called the B-series). We can still speak of the present, but it must always be understood from the perspective of a particular moment under consideration. The most we can say, for instance, is that from the perspective of the 3rd of March 2018, the 2nd of March is in the past and the 4th is in the future.

Each of these theories has a number of models, which are concrete proposals for the nature of time that satisfy the requirements of the theory. Confusingly, these models are also sometimes called “theories.” A-theoretic models include presentism, which holds that only the present moment of time is real, while the past moments were once real and the future moments have not yet become real; the spotlight theory, which holds that all moments of time are equally real but only one ever has the property of “presentness”, which leads to us visualizing time as a spotlight gradually moving over a fixed timeline; and the growing block theory, which holds that once a moment is real is stays real, resulting in all past moments being equally real and forming a “block” of time, with the present being on the edge of this ever-growing block. B-theoretic models include four-dimensionalism, which treats time like a sort of spatial dimension, holding that objects have temporal parts spread across the fourth dimension of time just like they have spatial parts spread across the first three dimensions of space; and eternalism, which we will here take to be the model that all moments of time are equally real without any having the status of being objectively present, but not necessarily construed as temporal parts of objects either.

As for God’s eternity, the Thomistic view is that eternity and time represent fundamentally different modes of being. Eternity is not merely about existing without beginning or end, since this would be consistent with existing in time as long as we stipulate that (1) either time itself has no beginning or end or (2) God entered time upon creation.1 The Thomistic view can be seen as a consequence of Boethius’ definition of eternity, which says that it is “the complete possession, all at once, of illimitable life.” Such an existence is incompatible with being in time, since temporal existence requires that we have our life bit by bit rather than having all of it at once. Accordingly, God’s eternity means that he must be outside of time, and the problem of eternity has to do with the relationship between an eternal God and his temporal creation.

Thomistic and analytic approaches to time

Now, for us Thomists who are familiar with the analytic distinction between A- and B-theory, it is natural to wonder how it applies to God’s eternity and his relation to time. What is not always realized, however, is that there is an important difference between the Thomistic and analytic approaches to questions of time. The Thomistic approach is Aristotelian, and therefore starts with an analysis of change. Aristotle starts by asking questions like whether change is possible and what it consists in, and considers examples like that of a person becoming educated and an object moving location. By contrast, the analytic approach — by which I mean the approach of those in the analytic tradition broadly following McTaggart — starts with the ontology of the passage of time. The main point at issue in the debate over A- and B-theory is whether the passage of time “flows” from past to future. On the A-theory it flows as the present moves from moment to moment, while on the B-theory it is in some sense static.

We saw the analytic approach in action during our discussion on McTaggart’s paper, wherein he switches between questions about changes to reality (which is change in the everyday sense of the word) and questions about changes to the time series, as if these were interchangeable. On the Thomistic approach, time is just the measure of change,2 and it makes little sense to speak of the time series itself changing, as if this could be decoupled from the change to reality which it measures. Indeed, from a Thomistic perspective the analytic approach can seem to treat time as a sort of quasi-substance, which is certainly the impression one gets from McTaggart’s talk of moments of time merging into one another or changing properties.

We can illustrate the difference between the two approaches by considering how they would attempt to answer the question of whether temporal becoming is an objective feature of reality.

For the Thomist, temporal becoming is the feature of things when they change, as when an uneducated person becomes educated or a physical object moves from one place to another. Every change involves a coming-to-be of what was not before, and in this case the becoming is of things and in time. Given this sense of temporal becoming, we can determine whether it is an objective by determining whether change is real. And since change is evident to our experience, all we need is an account of it that shows its possibility, and therefore that our experience of it need not be an illusion.

On the analytic approach, things are less clear, because temporal becoming sometimes takes on a different sense and because the two senses are not always clearly distinguished. It’s difficult to avoid talking about changes to everyday things like people and physical objects, but with a primary concern for the ontology of time this talk gets mixed up with talk about changes to the passage of time itself.3 We are no longer simply interested in whether someone who is uneducated can become educated in the future, but also whether that future moment itself is something that can become present. This is not simply a becoming in time, but a becoming of time itself. The result is the conflation of temporal becoming with the A-theory, since only the A-theory involves the passage of time being in flux. Given this sense of temporal becoming, in order to determine whether it is objective we need to determine whether the A-theory is true, and that our experience of the passage of time itself (which is much less evident than our experience of change) is not an illusion.

So these two approaches give us two senses of the notion of temporal becoming, namely becoming in time and becoming of time. The former arises from considerations of change in the Aristotelian sense, as when an uneducated person becomes educated, and a physical object changes place. The latter arises from considerations of how the moments of time itself might change, as when a future moment takes on “presentness.”

The compatibility of (Aristotelian) change with B-theory, and its irrelevance

The upshot of all of this is that the analytic debate over theories of time is irrelevant to Aristotelian and Thomistic concerns. Both A-theorists and B-theorists recognize the reality of time with its peculiar feature of being ordered according to before and after, which is all the Aristotelian needs. As Aquinas said, “time is nothing else than the reckoning of before and after in movement” (ST I Q53 A3 corp).

Failure to recognize the different senses of temporal becoming has led some to conflate views they shouldn’t.4 The B-theory, for instance, is sometimes labeled “Parmenidean,” as if these two views are even remotely similar. Parmenides denied the existence of any distinctions in reality whatsoever, which leads to the denial of change and therefore the denial of any meaningful distinction between before and after. But the B-theory presupposes a distinction between before and after, since this is built into the relations earlier-than and later-than.

Another claim is that the B-theory excludes the possibility of change, and is therefore at odds with the Aristotelian commitment to its reality. Why does the B-theory preclude change? Well, the argument goes, if all moments of time are equally real, then the earlier moments when someone is uneducated are equally as real as the later moments when they are educated, and so they never become educated. But this clearly equivocates the two sense of becoming we’ve been discussing. The Aristotelian concern is whether someone who is uneducated at some time t1 can become educated by some later time t2, not whether t1 and t2 can somehow change their properties of “presentness.” All the Aristotelian needs is that a person can persist through time while varying in their educatedness, which the B-theory happily provides. What the B-theory does not provide — but which is irrelevant to the Aristotelian — is that this happens together with a change to the moments of time themselves. Again, the Aristotelian is concerned with becoming in time, not becoming of time.

Once we recognize the difference between Aristotelian temporal becoming and analytic temporal becoming, we can see that Thomists can happily hold to either the A- or B-theory. The analytic debate just isn’t something we have a stake in. But here’s the kicker: this doesn’t help us in any way with the problem of eternity! It is tempting to think that the B-theory would give us an automatic explanation of the relationship between the eternal God and his temporal creation, but it doesn’t. Why? Because at the end of the day, the B-theory is still a theory about time.

Let me explain.

We’ve said that time is the reckoning of before and after in the process of change, but what we haven’t mentioned is that before and after can be reckoned to something on account of a change to something else. This is an instance of what’s been called “Cambridge change,” which Feser describes as follows:

Here, building on a distinction famously made by Peter Geach, we need to differentiate between real properties and mere “Cambridge properties.” For example, for Socrates to grow hair is a real change in him, the acquisition by him of a real property. But for Socrates to become shorter than Plato, not because Socrates’ height has changed but only because Plato has grown taller, is not a real change in Socrates but what Geach called a mere “Cambridge change,” and therefore involves the acquisition of a mere “Cambridge property.”

There’s a certain ambiguity in this that we’ll discuss later, but for now consider the example he gives. Socrates remains the same height while Plato grows, and on account of this we can reckon before and after for Socrates: before he was taller than Plato and afterwards he was shorter than Plato. Thus, there’s a sense in which the change of other things can bring us along with them through time. Since this results from our being able to reckon before and after through changes to things in time, and since both the A- and the B-theory give us this, this will apply on both theories.

The real problem of God’s eternity, then, isn’t about whether the nature of time is such that all moments are equally real, but about how our movement through time doesn’t bring God along with us. And since this happens for both A- and B-theories of time, neither of them is capable of solving the problem.

Starting over with relations

Rather than a theory of time, what we need is a theory of relations. The reason Plato brings Socrates along with him through time is that Socrates is really related to Plato in some respect. In the above example it is that they are really related in regards to their height, but it could equally have been their relative location, color, age, or whatever. Conversely, if Socrates were not really related to Plato with respect to some feature of Plato that changes, then there would be no way of reckoning before and after for Socrates in terms of a change in Plato.

Aquinas worked out a detailed theory of relations, and we will summarize the relevant parts here. First, relations are divided into real relations, which obtain in reality prior to any consideration by an intellect, and logical relations, which result from such consideration. Socrates being taller than Plato is a real relation, but Socrates being to the left of Plato is logical since it is dependent upon how one considers their relative positions. When something has a real relation to another thing we say that it is “really related” to it. In English, the word “really” is often used to mean “truly” — as when we say something “really happened” — but in our present case “really” just indicates the nature of the relation. Socrates being to the left of Plato is not a real relation, but it is nevertheless true that Socrates is to the left of Plato.

Now, a relation between two things is not some separate reality floating outside of those things, but is instead grounded in them. When we have some relation R between A and B, it is therefore technically more precise to speak of R as a pair of relations, R1 from A to B and R2 from B to A. Socrates is taller than Plato (R1) and Plato is shorter than Socrates (R2). Each relation has a foundation in the thing it relates from, and this foundation grounds how that thing relates to others. For instance, Socrates has a certain height H, by virtue of which he will be shorter than things with heights taller than H and taller than things with heights shorter than H. This generic relational fact comes to be “resolved” to one of the alternatives when considered with respect to a particular individual: Plato has a height shorter than H, and so Socrates is taller than Plato. Notice that since the relation from Socrates to Plato will depend on both their heights it can change without Socrates ever changing, as when Plato changes his height while Socrates remains the same. It is this change in the relation from Socrates to Plato that brings Socrates through time when Plato changes.

We can also talk about the type of relation, which is derived from the type of its foundation: the taller-than relation is based on height while the brighter-than relation is based on color. In addition to the foundation in A, a real relation from A to B requires something in B of the relevant type, which we might call the relation’s co-foundation. It makes little sense, for instance, to say that Socrates is taller or shorter than an immaterial angel, since a relation of height from Socrates to another thing requires that that thing have a height as well. There is no co-foundation of the relevant type in the angel.

We say that the co-foundation must be of a “relevant” type rather than the “same” type because sameness is not always required. The height relation is an example that requires the co-foundation to be the same type, but consider what happens when I come to know a material object. In this case I take on its form in my mind, which serves as the foundation for a real relation from me to it and which has the object’s own form in itself as the co-foundation. But these two forms have different types: the form in my mind is intentional while the form in the object is entitative; the form in my mind does not turn my mind into that object whereas the form in the object’s matter does.

Knowledge is also an example of what is called a non-mutual relation. We have said that my real relation to the object has its foundation in the intentional form in my mind and its co-foundation in the entitative form in the object. This works because of the intentional form by its very nature refers to the object of the intention. But the entitative form is about constitution rather than reference, and so does not refer back to the intentional form in my mind. It can serve as the foundation of relations to other things by comparison to their entitative forms, but that’s about it. This means that there is no corresponding real relation from the object to me that has its entitative form as foundation and the intentional form in my mind as co-foundation. This asymmetry in foundation and co-foundation is what makes the relation non-mutual. When a real relation from A to B is can be turned into a real relation from B to A simply by flipping the foundation and co-foundation, then that relation is mutual.

If this were not complicated enough, consider what happens with active and passive powers. Here we have an agent with an active power (ability to influence others) and a patient with a passive power (capacity to be influenced by others), and when the agent actually does influence the patient then we have action and passion. The active power of an agent is grounded in some actuality (actual feature) of the agent, like motion, size, intentions, and so on. Any relation that arises from the active power, then, will have this ground as its foundation, which will determine which co-foundations are relevant. The passive power of a patient is slightly different in that it is grounded in the potential of the patient to be influenced in a particular way. This potential will be the foundation of the relations that arise from the passive power, and the co-foundations will be any actuality that can actualize it.

There is an important asymmetry here, in that the conditions for an agent to really relate to the patient are different from the conditions of the patient to really relate to the agent. For a patient, all that is needed is something capable of actualizing it, but for the agent, the conditions will depend on the ground of the active power. It could happen, then, that a patient is really related to an agent by a non-mutual relation. Consider, for instance, a saw cutting through wood. We might say that the active power of the saw is grounded in the sharpness of its serrated blade, while the passive power of the wood has to do with its potentiality for being split. Certainly there is a real relation from the wood to the saw because of this passive power, but as for the active power the wood is not really comparable in terms of sharpness or serratedness. The wood is really related to the saw, then, with a non-mutual relation. Of course there are other real relations between the two that have to do with active and passive powers and which are mutual. The saw might be used to push the piece of wood, for instance, in which case the ground of the active power (the motion of the saw) has a relevant co-foundation in the wood (the motion of the wood).

The problem of eternity

With this we can state the Thomistic answer to the problem of eternity: God is not really related to creation, and is therefore not brought through time by our changes.

This arises from applying what we’ve said about relations to the nature of God. For Thomists, God is a being of pure actuality, with no potentiality in him whatsoever. This makes him radically unlike anything else in reality, all other things being made up of a combination of potentiality and actuality. Furthermore, since potentiality is what allows for the diversity of actuality within a thing, it follows that God’s purely actual substance is the only possible foundation for real relations from him to others. But since pure actuality is so different to anything else in existence, it follows that there can be no relevant co-foundation to this purely actual foundation, and that therefore God cannot be really related to anything else.

Creation is still really related to God, mind you, but this relation is non-mutual. We are really related to God by virtue of our dependence on him for our being, and by virtue of being ordered toward him as the ultimate final end (cf. ST I Q44). Both of these arise from us being patients of God’s activity, and it is because of the potentialities in us that we can be really related to him — although pure actuality might be very different from us, it is nevertheless capable of actualizing all the potentials in us. Conversely, since God has no potentiality in himself there can be no chance of him really relating to us by virtue of us acting on him in some way.

Not only does God’s pure actuality exclude real relations from him to us or our acting on him, but it also excludes the possibility of change within him. All change involves the actualization of a potential, after all, and so without a potential there is no possibility of change. This notwithstanding, he is the source of all actualizations of potentials, including all instances of change. Thus God is called the Unmoved Mover, or Unchanged Changer, or more generally the Unactualized Actualizer. It might sound a bit strange to say that something could cause change without itself changing, since in our experience these tend to coincide. But it is a consequence of the fact that action and passion arise by an actuality of an agent actualizing a potential of a patient.5 This does not require that the agent’s actuality itself be the actualization of a potential, even if that happens with all the material agents we experience in the world.

Now, we might wonder why God would not be really related to us by virtue of knowing us. God is omniscient, after all, and earlier we mentioned that a knower is really related to the object of their knowledge. Here we must again appreciate the difference between God and ourselves. We come to know things outside ourselves through inquiry and exploration, by means of which we acquire the intentional version of its form in our mind. The entitative form in the object stands as a measure to our conception of it, and it is to the extent that our conception fulfills this measure that it is said to be true or accurate. With God, things look very different. His act of knowing reality is the same act whereby he creates and sustains everything in reality, and so he has no need of inquiry or exploration. He does not discover anything and has no need to acquire new knowledge by means of taking on the intentional forms of things. Since it is by his activity that all things continue to have their being, and since his act of knowing is the same as this activity, it also follows that God’s knowledge is measure of things rather than the other way around. All of this means that God’s knowledge does not make him really related to us like our knowledge makes us really related to the objects of our knowledge.

So, God does not change and is not really related to things that change. This means that there is no way of reckoning before and after for him and that therefore he is not in time. This notwithstanding, he is still the creator and sustainer of everything, and by virtue of this we are really related to him. Just as God is an unchanged changer, so too is he the non-temporal cause of things in time. We must remember, of course, that being really related to something is not the same as being truly related to it. Despite not being really related to us, God is still truly related to us as Lord, Creator, Knower, and so on; it’s just that these true relations are based on logical relations from him to us rather than mutual real relations between him and us.

Now before we conclude, we said earlier that there is an ambiguity in the notion of Cambridge change, and we are finally in a position to see why. Sometimes Cambridge change is proposed as a solution to the problem of God’s eternity, but of itself this is insufficient. To say that God only undergoes Cambridge change is to say that he does not undergo any change within himself. This is fine so far as it goes, but it doesn’t explain why he isn’t brought through time by changes to other things — as we saw in the example of Plato and Socrates we used to introduce Cambridge change. This further step requires the approach we’ve outlined in this post. The upshot of this is that either we should say (1) that God doesn’t even undergo Cambridge change, or (2) that Cambridge change must be divided into instances that bring us along through time and instances that don’t. In this second option, the two species of Cambridge change are distinguished by whether there are the relevant real relations in place or not.

Conclusion and further reading

So, Ante, thanks for the question and sorry for taking so long to reply. As I see it, the Thomistic approach to time is largely indifferent to the analytic debate over A-theory and B-theory, and the problem of eternity is not caused or solved by embracing either of these. What we need for a solution is an account of when and why things are brought through time, and an explanation for why this does not apply to God. To this end, the Thomistic account of relations provides us with a promising start. I hope what I’ve managed to outline here helps.

On the topic of relations, Mark Henninger’s Aquinas on the Ontological Status of Relations and David Svoboda’s Aquinas on Real Relation are both excellent discussions on the account of relations laid out by Aquinas. From Aquinas himself, perhaps the most important place to start is his discussion in question 7 of the De Potentia, especially articles 9–11. His discussions on God’s knowledge through his substance and the divine relations in the Summa Theologica are also noteworthy, since they push the account of relations to its limits when applying it to God.

More broadly, Edward Feser’s Classical Theism Roundup is a great resource for thinking through issues like eternity. Moreover, while I think Thomists don’t have a stake in the analytic debate between A-theory and B-theory, that is not to say that we don’t have interesting contributions to make. A case in point is Elliot Polsky’s Thomistic Special Relativity, which provides a three-dimensionalist account of length contraction and time dilation using a Thomistic framework that is different from other A-theoretic approaches I’ve seen.


  1. This is the view of William Lane Craig. See, for instance, his God, Time and Eternity. I also discussed it in my pre-Thomist days in an earlier post.
  2. Or, more accurately, it is the numbering of change according to “before” and “after”. (ST I Q10 A1 corp.) We’ve discussed before the connection a measure must have with what it measures.
  3. I’m not the only one who sees this. According to the SEP article on Being and Becoming in Modern Physics, “What emerges from the McTaggart literature is, first of all, a tendency to identify the existence of passage or temporal becoming with the existence of the A-series (that is, to think of becoming as events changing their properties of pastness, presentness or nowness, and futurity) and hence the tendency for debates about the existence of passage to focus on the merits or incoherence of the A-series rather than examining alternative accounts of becoming.” Note that the “events” mentioned in the parenthesis should be taken to mean “event-slices,” since an event in the everyday sense is something that spans multiple moments of time, and not all slices of it will be present (or past, or future) simultaneously. Again, this is a usage that we see in McTaggart’s paper.
  4. I stumbled upon a recent example of this while writing this very post.
  5. See my earlier post Lonergan on Aquinas on Causation for a discussion of this in Aquinas, as well as the essential agreement between him and Aristotle despite a terminological difference.

Paul’s eschatological ethics

There was a distinct moment when it dawned on me that I had missed something important in Paul’s thinking on the Christian motivations for doing good works. During a Bible study we were busy discussing the following passage:

Owe no one anything, except to love each other, for the one who loves another has fulfilled the law. For the commandments, “You shall not commit adultery, You shall not murder, You shall not steal, You shall not covet”, and any other commandment, are summed up in this word: “You shall love your neighbor as yourself.” Love does no wrong to a neighbor; therefore love is the fulfilling of the law.

Besides this you know the time, that the hour has come for you to wake from sleep. For salvation is nearer to us now than when we first believed. The night is far gone; the day is at hand. So then let us cast off the works of darkness and put on the armor of light. Let us walk properly as in the daytime, not in orgies and drunkenness, not in sexual immorality and sensuality, not in quarreling and jealousy. But put on the Lord Jesus Christ, and make no provision for the flesh, to gratify its desires. (Rom 13:8–14)

Paul gives two reasons for why our lives should be characterized by love. The first is that love fulfills the law, and in the course of the preceding discussion of Romans we’ve seen that the law is something good and from God, and therefore something desirable. When turning to the second reason he shifts into metaphorical language, saying that we should awake from sleep and walk in the light. From the way he proceeds to talk it is clear that this is another way of speaking about obedience to God, but what’s interesting is the motivation he gives for it. He says that, “the hour has come for you to wake from sleep. For salvation is nearer to us now than when we first believed.” (13:11)

Now, if it is not clear to you why this is significant, let me back up and explain. For the longest time I had thought of the motivations for obedience in terms of what we might call “past-orientated” and “present-orientated” ways. Paul himself sometimes refers to these kinds of motivations in his letters, and so it wasn’t without warrant that I thought in these terms. For example, he urges the Corinthians to use their bodies with integrity because they are the temple of the Holy Spirit, and reminds them that they are no longer their own but were bought at a price (1 Cor 6:19–20, 7:22–24). He encourages the Ephesians to forgive one another because God hadforgiven them in Christ (Eph 4:32), and to walk in love as Christ had loved them (5:1–2). He calls the Philippians to follow the example that was set by Christ in putting others before oneself (Phil 2:4–6), and he explains to Timothy that Christ had set an example in his perfect patience for those who were to believe in him (1 Tim 1:16). The problem was this: I had so habituated myself into thinking in terms of past- and present-orientated motivations that I had unconsciously excluded the possibility of future-orientated motivations altogether.

And I would learn in that Bible study two things. First, it was not just me, but everyone in the discussion had done the same thing. And second, there was more to the problem than I originally thought. I pointed out the future-orientated motivation Paul gives in the passage, and with great interest asked the natural next question: how is our hope of future salvation supposed to motivate our present actions? I wasn’t equipped to answer the question, since it had never occurred to me to ask it before. But I discovered that night that no-one else was equipped to answer it either. The others did their best to give answers, but every attempt was inescapably couched in past- or present-orientated language, and once the fatigue of failed attempts became too much to bear the conversation moved on. But the question remained unanswered, and I remained unsatisfied.

This was roughly two years ago, and I haven’t stopped thinking about this since then. In the course of puzzling over it, I’ve come to refer to this feature of Paul’s thought as his “eschatological ethics.” Ethics because it has to do with living well in obedience to our creator and Lord, and eschatological because the motivation for this obedience arises from our hope in salvation on the final day, called the “eschaton” in theology, and often referred to as the “day of the Lord” in scripture. It’s worth giving this feature of Paul’s thought a name because, as it turns out, future-orientated motivations come up more often than past- or presented-orientated ones. We cannot understate the significance of this point. It means that without the adequate conceptual tools and practice in using them, we will miss how one of the New Testament’s most prolific writers connects his theology with its ethical implications.

Now, for a long while I had tried in vain to determine the way this connection was supposed to work. That is, I had sought the single motivational link connecting our future hope and present actions that could explain how Paul can so easily draw out the various ethical implications he does. More recently, however, I have come to realize that Paul actually recognizes more than one such link, and that he happily emphasizes different ones depending on the occasion of the particular letter we’re reading. In light of this realization, the task shifts from trying to find an abstract enough link that explains everything, to categorizing multiple links and reflecting on how they relate to one another.

In what follows, we will look at examples of Paul’s eschatological ethics, and then discuss three ways that our future hope is linked to our present actions.

Examples of Paul’s eschatological ethics

Paul does not seem to have developed a technical vocabulary for speaking about the connection between future hope and present action, but he does have general ways of speaking about hope and action separately. Although some of his letters are quite systematic they are still letters written for different purposes, and so we find him using a wide vocabulary and different imagery when talking about particular topics.

When he speaks about hope he has in mind a forward-looking anticipation for salvation on the day of the Lord. Connected to this is, naturally enough, a future-orientated understanding of salvation itself — an example of which we saw above in the Romans passage — as well as the idea of a calling to this hope — examples of which we will see in due course. And although used more fluidly, he also refers to the future glory that will be revealed on the final day.

Regarding good action, or obedience, Paul uses various metaphors and terms. We saw above that the expression of this action is love, and that it is spoken of metaphorically as walking in the light. Other times he will speak of being sober-minded or self-controlled. Or he will use the metaphor of athletics and refer to competing according to the rules, while other times he will use language more inspired by Old Testament law and refer to cleansing ourselves from defilement.

The variety of his language goes beyond this small sample, as we will see in the list below. We will consider a number of passages in the order that they appear in the New Testament, skipping over the Romans passage we considered above. This list is quite long, partly to make a point about how ubiquitous this kind of thinking is in Paul. The length notwithstanding, this list only contains those references where the future-orientated motivations are easily discerned and separated out from the broader context of his argument — which is to say, there is even more out there.

Romans 15:1–4

We who are strong have an obligation to bear with the failings of the weak, and not to please ourselves. Let each of us please his neighbor for his good, to build him up. For Christ did not please himself, but as it is written, “The reproaches of those who reproached you fell on me.” For whatever was written in former days was written for our instruction, that through endurance and through the encouragement of the Scriptures we might have hope.

He explains that as fellow members of Christ’s body (cf. 12:3–21) we are to help each other in our weakness (present action), that we might endure until the end and thereby not lose hope (future hope).

1 Corinthians 9:24–27

Do you not know that in a race all the runners run, but only one receives the prize? So, run that you may obtain it. Every athlete exercises self-control in all things. They do it to receive a perishable wreath, but we an imperishable. So, I do not run aimlessly; I do not box as one beating the air. But I discipline my body and keep it under control, lest after preaching to others I myself should be disqualified.

This comes as an explanation for Paul’s serving of others as an apostle of the gospel of Jesus, that he may share in the blessings that it brings with those who hear and accept it (cf. 9:23). The analogy of runners in a race clearly recognizes a prize at the end (future hope) as the motivation for running with self-control so that he may not be disqualified (present action).

1 Corinthians 15:32b–34

If the dead are not raised, “Let us eat and drink, for tomorrow we die.” Do not be deceived: “Bad company ruins good morals.” Wake up from your drunken stupor, as is right, and do not go on sinning. For some have no knowledge of God. I say this to your shame.

The “dead being raised” refers to the resurrection of the dead on the day of the Lord, when everyone will be judged. In the surrounding discussion, Paul is defending the resurrection of Jesus as a pre-figuring of this final resurrection, and using this as a motivation for the Corinthians to get their act together. Without the hope of such a resurrection (and implied judgment) there is little reason to act in obedience to God, but with such a hope there is very good reason to do so. Thus, in light of the resurrection (future hope), he calls them to wake up from their drunken stupor and live appropriately (present action).

2 Corinthians 5:9–10

So, whether we are at home or away, we make it our aim to please him. For we must all appear before the judgement seat of Christ, so that each one may receive what is due for what he has done in the body, whether good or evil.

Here it is clear that the future judgment motivates our present actions.

2 Corinthians 7:1

Since we have these promises, beloved, let us cleanse ourselves from every defilement of body and spirit, bringing holiness to completion in the fear of God.

The promises he is referring to were just stated in the preceding context (2 Cor 6:16–18), and speak of God’s promise that he will welcome his people (future hope) if they separate themselves from uncleanness (present action). From this it is clear that complete (or perfect) holiness refers to being with God most fully, which is the result of salvation on the day of the Lord, and which Paul sees here as motivating us to cleanse ourselves.

Galatians 5:5, 22–23

For through the Spirit, by faith we ourselves eagerly wait for the hope of righteousness… But the fruit of the Spirit is love: joy, peace, patience, kindness, goodness, faithfulness, gentleness, self-control; against such things there is no law.

Here the fruit of the Spirit are the present actions produced by the work of the Spirit, which involves pointing us to our future hope.

Galatians 6:7–9

Do not be deceived: God is not mocked, for whatever one sows, that will he also reap. For the one who sows to his own flesh will form the flesh reap corruption, but the one who sows to the Spirit will from the Spirit reap eternal life. And let us not grow weary of doing good, for in due season we will reap, if we do not give up.

Here he uses the analogy of the farmer reaping (future hope) the consequences of what they sow (present action), which is explicitly stated to be “doing good.” No doubt, this is a meditation on the previous chapter’s discussion of the work and fruit of the Spirit.

Philippians 2:12–13

Therefore, my beloved, as you have always obeyed, so now, not only as in my presence but much more in my absence, work out your own salvation with fear and trembling, for it is God who works in you both to will and to work for his good pleasure.

It is clear from this that Paul understood part of their motivation to be the working out of their salvation. That it is still to be worked out indicates that it is a future reality to which we strain to make our own.

Colossians 1:4–5

We always thank God, the Father of our Lord Jesus Christ, when we pray for you, since we heard of your faith in Christ Jesus and of the love that you have for all the saints, because of the hope laid up for you in heaven.

Paul notes that it is the hope of the Colossians that motivates their love for all the saints.

Colossians 1:21–23

And you, who once were alienated and hostile in mind, doing evil deeds, he has now reconciled in his body of flesh by his death, in order to present you holy and blameless and above reproach before him, if indeed you continue in the faith, stable and steadfast, not shifting from the hope of the gospel that you heard.

The presentation of them as holy and blameless is clearly a future reality, describing what will happen on the day of the Lord (cf. 2 Cor 1:14). This is clear since it is contingent on their continuing in the faith which, given the contrast with hostility of mind and doing evil deeds, no doubt carries with it the idea of obedience.

Colossians 3:1–5

If then you have been raised with Christ, seek the things that are above, where Christ is, seated at the right hand of God. Set your minds on things that are above, not on things that are on earth. For you have died, and your life is hidden with Christ in God. When Christ who is your life appears, then you also will appear with him in glory. Put to death therefore what is earthly in you…

At first Paul appears to be giving a past-orientated motivation for action, saying that we have died with Christ. But then, just before we get to the command to put our earthly passions to death, he switches to a future-orientated motivation, pointing us to the day when our life will appear with Christ in glory. This illustrates nicely a way of thinking about the connection between the present and future that can be seen elsewhere in Paul (eg. Eph 2:1–6, Phil 3:8–16), where our future hope is spoken about in terms of a present status. The best way to think about this is that in the present we are set on the trajectory toward a future hope that previously was out of reach. And just like a trajectory is identified by its being ordered toward a target, so too is our present status, when discussed in these ways, identified by its ordering us toward our future hope. Thus, Paul finds little difficulty switching between the two as he does in this above passage.

1 Thessalonians 5:8–11

But since we belong to the day, let us be sober, having put on the breastplate of faith and love, and for a helmet the hope of salvation. For God has not destined us for wrath, but to obtain salvation through our Lord Jesus Christ, who died for us so that whether we are [alive] or [dead] we might live with him. Therefore encourage one another and build one another up, just as you are doing.

Paul uses the language of being awake and sober again, and the motivation given for this is the destiny of salvation that God has laid out for us.

2 Thessalonians 2:14–15

To this he called you through our gospel, so that you may obtain the glory of our Lord Jesus Christ. So then, brothers, stand firm and hold to the traditions that you were taught by us, either by our spoken word or by our letter.

Future glory is the motivation to stand firm to the traditions, which we see later are connected with proper action (3:6).

1 Timothy 4:6–10

If you put these things before the brothers, you will be a good servant of Christ Jesus, being trained in the words of the faith and of the good doctrine that you have followed. Have nothing to do with irreverent, silly myths. Rather train yourself for godliness; for while bodily training is of some value, godliness is of value in every way, as it holds promise for the present life and also for the life to come. The saying is trustworthy and deserving of full acceptance. For to this end we toil and strive, because we have our hope set on the living God, who is the Savior of all people, especially of those who believe.

The value of godliness and the end toward which we strive is the hope of eternal life with the living God.

1 Timothy 6:11–14

But as for you, O man of God, flee these things. Pursue righteousness, godliness, faith, love, steadfastness, gentleness. Fight the good fight of the faith. Take hold of the eternal life to which you were called and about which you made the good confession in the presence of many witnesses. I charge you… to keep the commandment unstained and free from reproach until the appearing of our Lord Jesus Christ.

Paul starts by listing all these components of Christian life, which eventually leads to a statement about its motivation: to take hold of the eternal life to which you were called, and to keep going until the appearing of Jesus on the day of the Lord.

1 Timothy 6:18–19

[The rich] are to do good, to be rich in good works, to be generous and ready to share, thus storing up treasure for themselves as a good foundation for the future, so that they may take hold of that which is truly life.

The motivation for action is to take hold of true life, which is eternal life in the future.

2 Timothy 2:3–6

Share in suffering as a good soldier of Christ Jesus. No soldier gets entangled in civilian pursuits, since his aim is to please the one who enlisted him. An athlete is not crowned unless he competes according to the rules. It is the hard-working farmer who ought to have the first share of the crops.

Particularly the athlete and farmer analogies make sense only if we understand the life of a Christian as one governed by looking forward.

2 Timothy 4:6–8

For I am already being poured out as a drink offering, and the time of my departure has come. I have fought the good fight, I have finished the race, I have kept the faith. Henceforth there is laid up for me the crown of righteousness, which the Lord, the righteous judge, will award to me on that Day, and not only to me but also to all who have loved his appearing.

In reflecting on his life, Paul understood it as something done motivated by what will happen on the last day.

Titus 2:11–14

For the grace of God has appeared, bringing salvation for all people, training us to renounce ungodliness and worldly passions, and to live self-controlled, upright, and godly lives in the present age, waiting for our blessed hope, the appearing of the glory of our great God and Savior Jesus Christ, who gave himself for us to redeem us from all lawlessness and to purify for himself a people for his own possession who are zealous for good works.

Paul characterizes the life of people who have been saved and who are zealous for good works as that of waiting for their blessed hope.

Having gone through references from across Paul’s writings in the New Testament, we now come to the question of how future hope is meant to motivate present action. As can be seen from the passages above, Paul does not always state how he understands the link between the future and the present to work. Often he is satisfied to point his readers to the future and call them to act appropriately in light of it. Nevertheless, I think at least three links can be discerned from his discussions.

In a previous post we explained that works still play an important role in our future salvation, even though we are justified by faith alone. This realization is key to understanding the first link between our future hope in this salvation and the way we conduct our lives. As we explained in that post:

… at the last judgement, only those who have lived perfectly obedient lives will be saved from God’s wrath. However, because everyone sins, we can at best live an imperfectly obedient life. Even though we desire God and seek him with an obedient heart, we cannot escape punishment ourselves because we cannot undo our previous failures. This is akin to a murderer who has since repented of his crimes, but still awaits punishment: it doesn’t matter how many people he saves, he is still guilty of murder and deserving of punishment.

Without the justification brought by Christ there is no middle ground between (1) a perfectly obedient life leading to life with God and (2) a sinful life leading to punishment. The implicit problem with this is that the former is out of reach, as should be clear to anyone who’s ever tried to live such a life. But if the latter option is inevitable, then it’s difficult to see what could motivate someone who has sinned to continue to try and be obedient. As Paul says, “If the dead are not raised, ‘Let us eat and drink, for tomorrow we die.’”

Jesus changes things by opening up a third way, namely an imperfectly obedient life perfected through justification by faith alone.1 Turning to him as King and doing your best to live under him is now sufficient to obtain the life with God that was previously out of reach, provided we continue to the end. And this is why the hope of future salvation for sinners motivates present action. We need to continue in our obedience perfected by faith until the end to take hold of the prize. Furthermore, this obedience will correspond to the complete ethical life, since our Lord is not just anyone, but the supreme creator who seeks our flourishing as the kinds of creatures he made us to be.

Nevertheless there are plenty of things that might get in the way of our continuing to the end, whether they be internal weaknesses or external pressures. Thus Paul calls Christians to endure, to stand firm until the end, to not give up, to value self-control, and to remember the immeasurable value of what we strive for.

While the first link conceives of present action as a precondition for our future salvation, the second conceives of it in terms of living up to the status we have been given — the status of being Christ’s treasured possession that will be presented to him on the final day.

We saw this in the Titus passage above, where Paul explains that we are to live godly lives while we wait for the appearing of Jesus, who gave himself “to purify for himself a people for his own possession who are zealous for good works.” (Tit 2:14) As he continues to reflect on this in the verses that follow he describes good works as “excellent and profitable” (3:8) while denouncing the opposite as “unprofitable and worthless.” (3:9) Given how he’s just described the final day, we must surely read these assessments in light of how our present actions contribute to or frustrate our being presented as a treasured possession of our creator and Lord.

This idea of living a life worthy of this future comes up elsewhere in Paul’s letters (Eph 4:1–5, Col 1:9–10), although not always in as straightforward a way as we see in Titus. Sometimes he will use the metaphor of a wedding ceremony and describe the church as a bride to be presented to her husband (Eph 5:25–27, 2 Cor 11:2). Other times he will speak of living so that we might be able to boast of one another on the final day (2 Cor 1:13–14, 1 Thess 2:19–20, Phil 2:14–16). Still other times he will speak of it in terms of us achieving glory in some sense (Rom 8:18–21, 2 Cor 3:18).

Now, the idea of glory is a bit obscure to modern ears, but it can help us understand what it means to “live up to” our status. It is sufficient for our purposes to note that a thing’s glory is the basis for it being appreciated, respected, or approved. The kind of glory Paul has in mind here is that of an inferior in the eyes of their superior, like a child before their parent, a student before their teacher, or (in Paul’s case) a creature before their creator.2 In each case the inferior takes pleasure in the approval of their superior, as when a father is proud of his son or a teacher is impressed by the hard work of her pupil. And it often happens that an inferior’s desire for such approval will express itself in the present with an eye to a future appraisal of their work by their superior. This is the sort of situation we find ourselves with Christ. Knowing that one day we will be presented to him, we do our best to live in such a way that is pleasing to him, so that when he looks at the manner of our life we might be found worthy of the divine accolade “Well done, good and faithful servant.” (Matt 25:21, 23, Luke 19:17)

Some might object to this on the grounds that what we are suggesting looks a lot like conceit or vanity, neither of which seem like appropriate motivations for the ethical life. But appearances can be deceiving, and we must not confuse a healthy appreciation of our work for corrupted versions of it. We should avoid overestimating the value of our work (conceit), but we should also avoid underestimating it, since both extremes fail to properly appreciate the good in one’s life. And we should avoid treating outward expressions as if they were everything (vanity), but neither should we settle for good intentions alone. Furthermore, arrogance has no place in a desire that is peculiarly that of an inferior looking to the approval of their superior.

But perhaps the problem is not with the appreciation of our work, but with the fact that we do good things for the appreciation of someone else. I think this objection gets at something important, for surely Christ wishes us to help others out of genuine love for them and not simply as a means to earning his approval. The alternative seems to make everything about us, which is at odds with his exhortation to put others before ourselves. So then, can we reconcile the desire for our own approval before Christ with the other-centeredness such approval requires? We can, by using a distinction we’ve mentioned before between first-order and higher-order desires. First-order desires are the everyday desires we have that by themselves don’t involve self-reflection, like our desire to help others out of love for them. Higher-order desires are self-reflective desires we have about the kind of person we want to be and the kinds of desires we want to have. Even though higher-order desires are always about ourselves — since they are self-reflective — they can nevertheless reinforce selfless first-order desires and behaviors, and in this way show us how to reconcile the two ideas above. For example, we might have the (higher-order) desire to be the kind of person who always has the (first-order) desire for the well-being of their friends, in which case we have a desire about ourselves that contributes to the formation of other-centered habits. More generally, the higher-order desire to be someone pleasing to Christ involves the many other-centered first-order desires that he finds pleasing.

A specifically Christian objection is that all this talk about seeking Christ’s approval seems to ignore the importance of grace and the need for the redemption from sin. But really this is a misunderstanding — just as it would be a misunderstanding to say that the desire for obedience undermines the importance of grace. Our glory is marred by our sin, and we would therefore have no hope of being pleasing to Christ were it not for his purifying us from sin by grace. We do not work to earn the status as Christ’s treasured possession, for this would be impossible. Rather, we acquire this status by grace. And knowing what this means for our future, we work to make every moment until then worthy of his approval, instead of wasting them on worthless acts that will be overlooked.

Just like the first link, living in this way will correspond to the complete ethical life, because we aim to live a life worthy of our creator’s pleasure in us as the kinds of creatures we were made to be. But in order for our future reality to properly motivate our present actions we must rid ourselves of faulty thinking that gets in the way. The three objections we’ve considered are representative examples of what to avoid: we must not fall into the opposite extremes of conceitedness or self-deprecation, vanity or disregard for action; we must not treat others as a means to our approval; and we must not forget that all of this is made possible by grace.

Whereas the first two links arise from the nature of our future hope — our final judgment and our presentation to Christ — the third link arises from the recognition of our present weakness as we make our way to that hope. Accordingly, it is more limited in scope than the first two, and is not able to motivate the complete ethical life.

In our journey together toward our future hope we will face trials and difficulties, and it is our susceptibility to such things that we call weakness. Of course, this is very general and we can expect it to take many forms. The point is that since we are in this journey together, it is incumbent upon each of us to look out for one another, so that we might all make it to the end. We see this sort of reasoning in the Romans 15 passage listed above:

We who are strong have an obligation to bear with the failings of the weak, and not to please ourselves. Let each of us please his neighbor for his good, to build him up. For Christ did not please himself, but as it is written, “The reproaches of those who reproached you fell on me.” For whatever was written in former days was written for our instruction, that through endurance and through the encouragement of the Scriptures we might have hope. (Rom 15:1–4)

In this passage we see past-, present-, and future-orientated thinking all working together: by following the past example of Christ and listening to the past instructions of Scripture we are to bear with one another in our present weakness so that together we might be able to endure to the end and thereby have hope that we will get to our future hope.

The easiest forms of weakness to bear are the ones that we share in equally with each other, since such equality fosters solidarity. The passage above, however, discusses a form that leads some of us to bear the consequences of the weakness of others. This is much harder, since by its very nature it divides us from one another — those whose weakness must be borne and those who must bear it. In these cases we must hold on to the deeper solidarity we have with one another, based on the fact that we are all on the same journey to the same future hope. In fact, this deeper solidarity is implicit in the first two links we discussed. We all have the same King who deserves our obedience, and in this way we are fellow citizens within his kingdom (cf. Eph 2:19, Phil 3:20). And it is not each of us individually that is presented to Christ, but all of us as one people that are his treasured possession (Tit 2:14, cf. Eph 5:27). Thus, it makes all the sense in the world that he can sometimes talk of the final day in terms of us boasting in one another (2 Cor 1:14).

Weakness is the key thing that gets in the way of us holding on to our future hope, and making it to the end. It is in light of our weakness in general that we are called to be steadfast, to endure, to not grow weary, and to rejoice in hope. And it is in light of specific weaknesses that we are called to be patient with one another (which I’ve discussed in more detail elsewhere), to be gentle, to bear with one another, and to forgive.

Conclusion

There is much more that could be said on this topic. We could discuss how Paul sometimes speaks of our future hope using present-tense language. We could further unpack how the links we outlined here interrelate with one another. We could explain how particular behaviors (the virtues, or the fruit of the Spirit) follow from our future-orientated motivations. We could see how eschatological ethics works in other authors of the New Testament. And so on.

This notwithstanding, what we’ve managed to say is a good start. We have called attention to an important feature of Paul’s thought, given it a name, shown its ubiquity and variety, and provided the beginnings of a framework for thinking about it.

If like me you’ve been missing Paul’s eschatological ethics, hopefully this post will help you to start recognizing and reflecting on this important idea in the New Testament.


  1. Or, if you prefer Piper’s model (described in the linked post), then you would instead characterize this third way as that of a faith that produces an obedience acceptable to God.
  2. CS Lewis, The Weight of Glory. For a very good explanation of “glory” in the biblical sense, though not directly connecting it to our present discussion, I highly recommend this talk by Tim Mackie.