Dialogue on God’s interaction with the universe

Bob: How can an immaterial God interact with a material universe?

Alice: The question itself needs to be questioned before we can answer it.

Bob: How so? It seems like a fairly straightforward question.

Alice: Well, consider the word “interact.” God does not interact with anything. To interact requires action going in both directions, and since God is pure actuality this is impossible. Rather God acts on and through creatures without them acting on him.

Bob: Ok, so we’ll change the question to how an immaterial God can act on or through a material creature.

Alice: It’s better but still has problems. When you ask “how” God can act, what type of answer are you expecting?

Bob: I’m not sure I lay out exactly the type of answering I’m looking for, but I can give you illustrative examples. Fire heats by inducing mean molecular motion, I pick up things with my hands, and one stone acts on another by knocking into it. In each of these cases, I can point to the means or process by which some action is performed by one thing on another.

Alice: But on that account, the question is loaded! In each case, you could give some organ, part, or some material property by which one thing causes something in another thing. None of these kinds of answers apply to God since he has no organs, parts, or material properties. And to assume this in the question at hand is to preclude the possibility of giving an answer.

Bob: I grant your point but how, then, am I to proceed? Surely there’s a legitimate question to be asked here? And if we can’t use physical categories to have the conversation, then what can we use? After all, surely all our knowledge comes from our experiences of physical things?

Alice: It is true that all human cognition starts with sense data. But through abstraction and other intellective acts, we can move beyond these data, so that while our knowledge starts with our experiences it needn’t end with them. We do this, for example, when studying infinities in mathematics or when picking out idealized models in physics. Even in imagining things that don’t really exist, like fictional characters and stories, we are moving beyond what we have experienced. I agree that there is a legitimate question to be asked, but my point is that it should not be understood as a physical question but as a meta-physical one.

Bob: Ok, granted that the question — and therefore answer — is metaphysical, how would you answer?

Alice: One of the broadest distinctions we have in metaphysics is that between act and potency. Just as we’ve been saying, we come to understand this distinction through everyday phenomena like change and multiplicity. And once we understand act and potency, we can then move beyond these phenomena to talk about things beyond our everyday experience, like God. It is with categories such as these that we need to approach the question.

Bob: I understand the distinction between act and potency, and I understand that God is conceived of as a being of pure actuality. But how does this distinction answer the question?

Alice: It doesn’t by itself answer the question. But it is the first step in showing that the question is, in a way, misplaced.

Bob: I don’t see how it could be misplaced. After all, it seems quite natural to ask how a thing without arms or legs could act on material things.

Alice: Let me explain. Once we arrive at the distinction between act and potency we can draw out various corollaries, two of which interest us here. First, things act only insofar as they are in act. The basic idea behind this is that acting on something involves actualizing potentials in that thing, and since potency cannot actualize anything this can only happen insofar as the thing acting is in act. Second, potency limits act. When an act is understood as the actualization of this or that potency, it becomes qualified (or limited) by that potency. For example, the act of mean molecular motion is of itself not limited to a time or place or speed, but when it comes to actualize the potencies in something being heated then it will be limited in these ways.

Bob: I don’t see how all of this relates to the question. How do either of these help us find the metaphysical hand by which God acts on a material thing?

Alice: The point is that he doesn’t need such a hand in the first place! As material beings, we exist through the actualization of potencies in our matter. As such, our actions are limited in various ways, which is why we cause by means of organs, parts, tools, contact, etc. A particular fire can’t heat something across the world because it’s limited by its matter to a specific place and time. A particular stone can’t simply make another move whenever, but has to collide with it, because its causal influence is limited to where and when it is.

Bob: And what about God?

Alice: As we’ve said, God is pure actuality, which is to say that there is no potency in him that limits his action. He simply brings about his effects immediately, without any need for the various means we need as material beings. This is why I said the question is misplaced. If anything is surprising it’s that we limited beings can interact with each other, not that the unlimited God can act on us.

Bob: That may be evident upon later metaphysical reflection, but I think the question arises quite naturally from our everyday experience of how things interact with one another. After seeing that things typically interact by various means that depend on their materiality, we quite reasonably ask how it is that an immaterial God could do something similar.

Alice: That’s a fair point. The answer, then, is that an immaterial God does not do something similar. He does not interact, but rather he acts. And he does not act by means of something, but rather he acts immediately. His action is similar to ours in that it arises from him being in act, but it is different from ours in that his being in act is not limited by any potencies within himself.

Bob: I see. In a way, it is almost an inevitable consequence of his being the creator of everything. If he needed a means by which to act, then this means could not have been created by him.

The real distinction

Whenever we have two concepts, A and B, we can ask to what extent the things they pick out in reality are distinct. If they pick out distinct realities, then we say that there is a real distinction between them. If they pick out the same reality, however, then we say that there is a real identity between them. Even if two concepts are really identical with one another we can still meaningfully talk about a distinction between them, and Thomists say this can happen in two ways.

A conceptual (or merely logical) distinction is when the two concepts pick out the same reality in every way, and the only distinction to be had is in the way we’re considering that reality. For instance, Superman and Clark Kent are conceptually distinct from one another. There’s nothing true of Superman that is not also true of Clark Kent, and vice versa. Another example is a particular incline that is understood as either a downhill or an uphill. These are the same thing considered from different perspectives.

A virtual distinction arises when the two concepts pick out the same reality, but where this reality is understood with respect to two other really distinct things. In other words, we say that A is virtually distinct from B when (1) both A and B pick out some reality Z, (2) A is Z understood with respect to some C and B is Z understood with respect to some D, and (3) C and D are really distinct from one another.

We saw some examples of virtual distinctions when discussing potential wholes recently, and we’ll repeat two of them here. First, faith is thinking with assent. Of itself, faith is a single action, but it has an intellective aspect (thinking) and a volitional aspect (assenting) each of which involves the use of a different power (the intellect and will respectively). These two aspects of faith, then, are virtually distinct from one another, because they are the same act understood with respect to distinct powers. Second, a water molecule arises from a single bond configuring two hydrogen atoms with one oxygen atom. Now, we can consider the configuration of one of the hydrogen atoms, and we can consider the configuration of the oxygen atom. These two concepts pick out the same underlying reality — the configuration making up the whole water molecule — but do so with respect to distinct elements of the water molecule. As such, they are virtually distinct from one another.

These, then, are the two non-real distinctions, and in each case we could say when such a distinction occurs. Can we do the same thing for real distinctions? One common proposal is that two concepts are really distinct when the realities they pick out are separable, that is when one can exist without the other. Now, certainly separability is a sufficient condition for a real distinction, but is it a necessary condition? For Thomists the answer is no, since we think that a real distinction can occur between inseparable things. In cases where two things are inseparable, then, what is the condition that accounts for their real distinction?

I want to suggest that what we said about virtual distinctions can help us answer this. Looking at the three sub-conditions I listed for virtual distinctions, the second is critical and what links the other two. It is because being understood with respect to C does not exclude being understood with respect to D that there can be one reality picked out by the two concepts. If one of these relations did exclude the other, then the two concepts must pick out distinct realities, and therefore be really distinct. We’ll call this the exclusion condition to distinguish it from the separability condition.

Now, if the exclusion condition is to be of value to us it cannot apply in all and only those cases the separability condition applies. There are clearly cases where the two conditions coincide. To give a simple example, let A pick out me thinking something, and let B pick out me thinking the opposite. Assuming I’m not beset with doublethink, these two realities exclude one another. And they are certainly separable from one another. To find a case of exclusion without separability we need to look a bit harder. Perhaps the most famous (or infamous) example is the distinction between essence and existence in created beings. Aquinas argues that this is a real distinction, despite the two being inseparable from one another. His argument is fairly involved, so here we’ll just sketch enough for illustrative purposes.

Sherlock Holmes and I have a number of important things in common. We are both composites of form and matter, for instance, and we have similar sets of natural powers, even if he has some of these to a greater degree than I. The most salient point is that we share a common essence, on account of which we are both called human and by which we are distinguished from other kinds of substances. As far as I’m aware, however, I exist and he doesn’t. What this means is that our common essence itself cannot differentiate between an existing human and a non-existing human. Put another way, our essence of itself is indeterminate between existence and non-existence. I exist, then, because my essence has something else added to it which determines it to existence rather than non-existence. This something else is called esse in Latin, and is variously translated into English as “being” or “existence.”

All of this might sound like a convoluted way of saying what amounts to the tautology that I exist because I have existence. But such a complaint rides on an ambiguity. When I speak of a common essence shared by myself and Sherlock I do not have in mind some abstract universal that lies outside of each of us, but rather the particular feature found in each of us in virtue of which each of us fall under that universal in the first place. To illustrate the difference between these two consider the simple example of two groups of wood, each organised into a square shape. In this picture there is (1) the universal squareness which is instantiated twice, (2) the particular square organisation which is in the first group, and (3) the particular square organisation which is in the second group. It is in virtue of each of the groups having the organisation in itself that it can fall under the universal in the first place. So too with the common essence shared by Sherlock and myself.

Just as my essence is in me, so too its determination to existence is in me. It is because my essence is determined by esse and Sherlock’s is not that I exist and he doesn’t. So, then, our earlier conclusion really amounts to the non-tautologous claim that a certain fact about me (that I exist) is true in virtue of some feature in me (my esse).

Now, the argument I ran with myself and Sherlock can be applied to any being, so that all beings exist in virtue of esse within them. Esse, therefore, accounts for the similarity between all existing beings insofar as they exist, which is to say it unifies all existing beings qua existing. Essence, on the other hand, diversifies and differentiates these beings from one another, by qualifying their existence in different ways. For instance, two beings A and B are similar to each other in that they both have esse and thereby exist, but differ from one another in that A’s essence makes him an existing human whereas B’s essence makes him an existing angel. The essences of material beings additionally requires that their existence be qualified to a place and time, which allows multiple beings of the same species to exist.

Since esse unifies and essence diversifies, it follows that these two concepts exclude one another. And since a being can’t exist without its essence and esse these two are also inseparable from one another. So we have an example of a real distinction on the basis of exclusion without separability.

Before we close, we must introduce an important nuance. Strictly speaking, all that is needed for A to be a distinctly existing being from B is for A’s essence to qualify its existence in a way that B’s does not. Notice, however, that this leaves open two options regarding B’s essence: either it qualifies B’s existence in a way A’s essence does not, or it doesn’t qualify B’s existence at all. In the latter case, B’s essence would do nothing to exclude it from being really identical with B’s esse. Nevertheless, it is clear from the foregoing that at most one being can have unqualified existence, and so in all other beings there will be the real distinction between essence and esse we’ve been talking about.

The threefold whole

In his Metaphysics Δ Aristotle says there are two senses of the term “whole”:

Whole means that from which none of the things of which it is said to consist by nature are missing; and that which contains the things contained in such a way that they form one thing.

The first sense corresponds to our usage of the word when we say things like, “he managed to eat the whole sandwich” and “she read the whole book in one day.” The second sense corresponds to what we refer to when we speak of general part-whole relations, for instance when we say that my arms and legs are part of my body. This second sense is what we’re interested in here. Aristotle further divides this into two kinds:

But this occurs in two ways: either inasmuch as each is the one in question, or inasmuch as one thing is constituted of them.

These are two very different kinds of whole. The second kind is perhaps the one we’re most familiar with: bodies are constituted by organs, tables are constituted by legs and tops, computers are constituted by transistors and other electronics. This kind is referred to as integral, so that integral wholes are constituted by integral parts. We might not think to talk about the first kind as a whole, but it does fit one sense of the general definition. It’s a whole in the sense that a universal applies to (and thereby “contains”) all the particulars that instantiate it: humanness contains all individual humans, treeness contains all individual trees, and so on. This kind is referred to as universal, so that universal wholes apply to universal parts.

Aristotle construes the difference between these two kinds of whole in terms of how the parts are made “one” in different senses. Integral parts come together to form one individual which we call the whole. We refer to this as numerical unity. Universal parts are each themselves an individual which instantiate a common universal. We refer to this as specific unity.

Later the Scholastics discovered a third kind, which they called potential. How potential relates to integral and universal depends on how you analyse the differences between the kinds. Aquinas, for instance, analysed them in terms of the presence of a whole in its parts, which in turn correlates to how truly the whole can be predicated of its parts. This led him to placing the potential as midway between the integral and universal:

… the universal whole is in each part according to its entire essence and power; as animal in a man and in a horse; and therefore it is properly predicated of each part. But the integral whole is not in each part, neither according to its whole essence, nor according to its whole power. Therefore in no way can it be predicated of each part; yet in a way it is predicated, though improperly, of all the parts together; as if we were to say that the wall, roof, and foundations are a house. But the potential whole is in each part according to its whole essence, not, however, according to its whole power. Therefore in a way it can be predicated of each part, but not so properly as the universal whole. (ST I, Q77, A1, ad1)


My preferred analysis is in terms of the intrinsicality of the potency and act by which the parts of a whole are distinguished and unified respectively. For the remainder of this post we will unpack this, and reflect on how the different kinds relate to one another on this account.

Now, any material being is a mixture act and potency (or, equivalently, actualities and potentials). By this we mean that it has capacities for various states or behaviours, some of which are realised. We call these capacities potentials, and insofar as a potential is realised we call it an actuality or an actualised potential. For example a coffee cup has potentials for being various temperatures, a person has potentials for being various levels of educated in some subject, and a squirrel has potentials for jumping and running. That last example indicates that potentials aren’t always potentials for static states, but can also be potentials for dynamic activities. So also actualities can be static or dynamic, depending on the kind of potential they’re the actualisation of.

These two things, namely (1) the distinction between act and potency and (2) the realisation that individuals are mixtures of various acts and potencies, enable us account for very fundamental features of reality like change and multiplicity. We’ve spoken about change before, but it’s worth saying something about multiplicity here. Parmenides famously held that multiplicity is impossible since if A and B have being, then the only thing that can distinguish them is non-being, which is nothing. But if nothing distinguishes them then they are not distinguished, and therefore they are identical. Thus everything is one, a unity without multiplicity. His mistake was failing to realise (as we have) that being is divided into act and potency, and that beings are mixtures of these two principles. Two things can be unified by being actual in the same way, but diversified (or multiplied) by this common actuality resulting from the actualisation of distinct potencies. So you and I can be unified in our both being educated, but diversified by the fact that my being educated is the actualisation of my potency for being educated and your being educated is the actualisation of your distinct potency for being educated. So long as we properly divide being into act and potency, then, we can affirm both unity and multiplicity.[1]

So that’s act and potency, next we turn to intrinsicality. Intuitively, to be intrinsic to something is to be wholly contained within it. Slightly more formally, A’s being B is intrinsic to A relative to some C insofar as A’s being B doesn’t depend on C. Alice’s being educated is intrinsic to her relative to Bob’s being educated, for example, because it does not depend on Bob’s being educated. Intrinsicality is, naturally enough, contrasted with extrinsicality. In a water molecule, the hydrogen’s bonding to the oxygen is extrinsic insofar as it depends on the cooperation of the water molecule.

It’s clear enough that the primary sense in which we talk about the acts and potencies of something is as intrinsic acts and potencies, since these are what constitute the being of that thing. In order to outline all three kinds of whole, however, we will need to expand our focus to secondary senses. That being said, when considering something in terms of an act and potency at least one of these must be intrinsic to that thing, since if this weren’t the case, no sense could be made of our considering that thing rather than something else.

In general a whole, in the sense we’re interested, is “a unity of ordered parts.”[2] Parts, of themselves, are diverse and are brought together into a unity through an ordering of some kind, like an arrangement or structure or process. Now, since act unifies and potency diversifies, it follows that a whole arises through the actualisation of the potencies by which the parts are distinguished from one another. So for each part we can talk about the actualisation that unifies it with the other parts, and potency that distinguishes it from the other parts.

This allows us to state our taxonomy of the kinds of whole. For any part, either this unifying actualisation is intrinsic to the part or it is not. If it is extrinsic then, as we said above, the diversifying potency must be intrinsic to the part. If the actualisation is intrinsic, then either the potency is also intrinsic or it is not. An integral whole arises when we have an extrinsic act and intrinsic potency, a universal whole arises when we have an intrinsic act and intrinsic potency, and a potential whole arises when we have an intrinsic act and an extrinsic potency.

Breakdown of the three kinds of whole
Breakdown of the three kinds of whole

Integral wholes

All of this is rather abstract, and some examples might help for clarity. Starting with integral wholes we’ve already seen an example: a water molecule made up of hydrogen and oxygen molecules. Each of the parts has an intrinsic potential to be bonded with the others. There is one bond which actualises all of these distinct potencies resulting in one water molecule, and so this actualisation is extrinsic to the parts. Second, there’s a simple wooden table made up of a tabletop on four legs. Here each of the five pieces have potencies for being structured in various ways, and the binding of them together into the table is an actualisation of these potencies. And finally, there’s a living animal. What the parts are here is not totally obvious; they might be the various organs, the interconnected organic systems, or the cells, bones, and other organic materials. Whatever they end up being, the point of interest is that the extrinsic actualisation here is a dynamic process involving the parts, rather than the static structure of the table. This process is what constitutes the difference between a living animal on the one hand, and a corpse on the other.[3]

With these three examples in hand, we can introduce some technical vocabulary. In an integral whole call the extrinsic actualisation the configuration, and call a part with the configuration abstracted away an element. The element is that in which the intrinsic potency inheres. If we consider a hydrogen molecule while abstracting away whether it is free or bound in some other molecule, then we’re considering the hydrogen molecule element. When we consider a free-hydrogen-molecule or a water-bound-hydrogen-molecule, then we’re considering the element together with a configuration.

Universal wholes

Moving on to universal wholes, let’s consider the example of the wooden table and how it differs depending on which kind of whole we’re considering. The integral whole in this case is the table itself, with the integral parts being the tabletop and legs. The universal whole, on the other hand, is tableness and the universal part of this whole is the individual table (that is, the particular instantiating tableness). Each table — each universal part — will have its own intrinsic actualisation that accounts for its being a table as opposed to something else. This actualisation is common to all tables (it is in virtue of this that we call them tables in the first place), but it is not some numerically one thing. Rather, each has their own instance of this actualisation, each being actualised in the same way.

Again we can introduce some technical vocabulary. Well actually, we can re-introduce some technical vocabulary first introduced by Aristotle. The common actualisation intrinsic to each universal part is called the form, and when we abstract away the form of a part we’re left with its matter. Of itself matter is indeterminate between a number of alternatives, and form is the determination to one of these. (Put in terms of act and potency, of itself matter has potencies for alternatives, and form actualises one of these potencies.) The difference with integral wholes may now be apparent: with integral wholes the elements are the individual pieces of wood, but with universal wholes the matter is the wood itself. After all, if we have a table of wood and we abstract away the table bit all we have left is the of wood bit.

Because much of modern science has focused on integral wholes, we as moderns will always be tempted to confuse form and matter for configuration and elements.[4] We’ve already seen the difference with the wooden table: the elements are the pieces while the matter is the wood. With the living animal the elements are often said to be the cells, and so the configuration would be the organising process of those cells.[5] For universal wholes, however, the matter of a living thing is called its body and the form of a living is called its soul.[6] Considered broadly, there are three classes of living things: plants, animals, and humans. The soul of a plant makes it vegetative, the soul of an animal makes it sentient, and the soul of a human makes it rational.[7] If we abstract away the particular soul of a living thing, then all we know is that it is living; and this matter we call a body. The lesson here is that form and matter carve up the world very differently from configuration and element.

One more example should do to get this point across: consider the case where my hand moves into your face. The motion of my hand alone is indeterminate between me attacking you, and me reaching to get something and hitting you by mistake. The form that determines which of these is the case is my intention. Together the motion (as matter) and the intention (as form) constitute my action. The configuration of my action, by contrast, would presumably pick out how I hit you with my hand, like the path my hand took through the air. This something very different from the intention of the action.

Potential wholes

Finally, potential wholes. Of the three kinds this is the most foreign to us, and it is also arguably the most fundamental. The key here is this: in both integral and universal wholes we have cases where a single act can actualise multiple potencies at once. This is clear enough in integral wholes, but it can also apply with universal wholes: an animal’s soul actualises potencies for walking, grasping, flexing, seeing, smelling, touching, and so on. Now, whenever a single act involves the actualisation of a number of potencies, we can distinguish between sub-acts of that act. If some act A is involves the actualisation of potencies P, Q, and R, then we can consider the sub-acts of A as the actualisation of P and the actualisation of Q and the actualisation of R. The potential whole is the act, and the potential parts are these sub-acts which are distinguish by extrinsic the potencies found in the elements.

Notice the difference here: the parts do not have potencies, but are just sub-acts we differentiate by reference to extrinsic potencies. Consider the water molecule again as an integral whole, so that we have a configuration of elements. Each part is the result of an element being actualised with the configuration, and so each part includes some potency inside it. The whole water molecule includes both potency (from the elements) and act (from the configuration). But now abstract away the elements so that all you’re left with is the configuration itself. This doesn’t include a potency; it is just an act. And when we sub-divide this configuration into sub-configurations (each the actualisation of a different element), these are also just acts: the configurings of the hydrogen molecules and the configuring of the oxygen molecule. Potency plays a role is distinguishing the sub-acts from one another, but the potencies are extrinsic to these sub-acts.

Something similar happens in the case of a form informing matter. For each distinct potency actualised by the form, we can discern a sub-act which is that form considered with respect to that extrinsic potency. The potential parts of a human soul are roughly the various powers it gives a human: vegetative powers like digestion, animal powers like walking and seeing, and rational powers like abstraction and judgement.[8]

So far we’ve illustrated potential wholes by reusing examples from integral and universal wholes. This is partly because we want to show the sense in which potential wholes are most fundamental, but also because it helps us gain some initial intuitions. There are other examples of potential wholes, two of which we’ll go through now. First, communities are potential wholes. This is true in general, but focus on one for now: an orchestra playing a piece of music. The playing is the result of a co-ordinated effort from all the members of the orchestra, and is a single activity of the orchestra. We can consider the sub-activities of this activity as the playing of the individual members, and these would be the potential parts of the playing of the orchestra as a whole.

Second, there are what we might call “composite actions” like faith. At its most general level, faith is thinking with assent. “Thinking” involves having intellectual confidence in something, less than certitude.[9] “Assent” picks out the mood of the thinking: that which I think I also desire. So thinking uses the intellect and assenting uses the will, but these are being used together in one and the same act, which we call faith. So then the act of faith is a potential whole with the potential parts of thinking and assenting, each distinguished by the rational faculty they are the use of.

With both integral and universal wholes we introduced technical vocabulary to capture the specific kind of act and potency at play in each case (configuration-element and form-matter). With potential wholes, however, the act in view seems to be as varied as actuality in general. As such, it seems the best we can do is distinguish between super-act and sub-act, where the super-act is the potential whole and the sub-act is the potential part. Depending on which kind of act we’re considering we’ll restrict the vocabulary, and we’ll usually drop the “super-” bit from the whole. We’ve been doing this all already: configurations and sub-configurations, activities and sub-activities, actions and sub-actions. We also sometimes spoke about the potential parts by using a proxy, as when we used powers as a proxy for sub-forms of an animal soul.


Aristotle discovered two kinds of whole: integral and universal. The Scholastics discovered a third, the potential whole, and extended Aristotle’s analysis of wholes in terms of predication. We saw an example of this in Aquinas, and in that case potential wholes fell between the other two kinds. With the present analysis in terms of intrinsicality there doesn’t seem to be a linear way of ordering the different kinds, although their relations are captured well in the diagram we saw earlier.


  1. One might wonder if we haven’t just pushed the question about what multiplicity is back a step, since multiplicity of things arises from multiplicity of potencies. But this misses the point since we’re not trying to give an analysis of multiplicity, but rather trying to account for the reality of multiplicity with our principles. Because Parmenides had just being and non-being he could not account for multiplicity. But because we have divided being into being-in-potency and being-in-act, we are thereby able to account for it.
  2. See Svoboda’s Thomas Aquinas on Whole and Part.
  3. Rob Koons discusses in some detail how this process interacts with the parts in his Stalwart vs. Faint-Hearted Hylomorphism. David Oderberg argues in his Synthetic Life and the Bruteness of Immanent Causation the process of life is one involving immanent causation.
  4. Even Eleonore Stump, who is a very careful expositor of Aquinas, falls into this trap. I made the same mistake in an earlier post.
  5. While it is common to refer to the elements of an organism as a cell, this is technically wrong. But the details are not particularly important to our present point.
  6. See Mike Flynn’s blogpost series In Search of Psyche (introduction, part 1, part 2, part 3, and part 4).
  7. This is a technical term: any animal we take to be rational is a human. See David Oderberg’s Can There Be a Superhuman Species? for a related discussion.
  8. We say they are “roughly” the powers, since strictly they are the vehicles of the powers. Every power is grounded in a particular intrinsic actualisation, which we call the vehicle of that power. But such technicality is not necessary here.
  9. As Aquinas said, “[Thinking] is more strictly taken for that consideration of the intellect, which is accompanied by some kind of inquiry, and which precedes the intellect’s arrival at the stage of perfection that comes with the certitude of sight.” (ST II-II, Q2, A1, corp)

The metaphysics of gender

I recently listened to this talk by John Finley titled The Metaphysics of Gender: A Thomistic Approach. Below are my notes of this. I skip the introductory remarks and follow the four-section division of the talk. Note that by “gender” here we do not mean the psychological or social construct introduced by modern feminists. Rather, by “gender” we mean the biological distinction between male and female. Some have come to refer to this as “sex” but in the introduction John notes that both terms have ambiguity and so he just picked one. By-and-large parentheses represent my own thoughts, but this is not always the case. And finally, the times for each of the sections are written next to each of their headings.

Aquinas’s position (8:56-20:30)

A man is a male human being and a woman is a female human being. Male and female are distinguished by their mode of generation: the male is that which can generate in another, while the female is that which can generate in itself. Whatever meanings man and woman could have, they need be connected to these meanings.

So, then, what is the connection between male or female on the one hand, and being human on the other? It does not affect that one has a human nature: one’s gender does not elevate or detract from one’s being a human being. Perhaps, it’s better to say that gender affects how one participates in human nature. “It might be better to say that men and women share human nature equally but differently, according to their respective generative abilities. In an analogous way, being blue-eyed and being brown-eyed pertain equally but differently to the human power of vision.” Nevertheless, gender must be a more significant personal attribute than eye-color, since it involves distinct organs, activities, and purposes. It is also more uniform than other less significant attributes, which appear more sporadically throughout the human population.

Thomas has two classifications of accidents: (1) a logical classification (in terms of genus, species, etc.) in The Disputed Questions on the Soul and (2) a metaphysical classification (as arising from form and matter) in On Being and Essence:

On the logical classification there are three sorts of accidents: proper accidents (eg. risibility in humans) result from the principles of the species and so characterise all members, inseparable accidents (eg. masculine and feminine) result from the principles of the individual through permanent causation and so characterise that member in a lasting fashion, and separable accidents (eg. sitting and walking) flow from the principles of the individual through temporary causation and so only characterise that member at particular times. The main focus here is the inseparable accidents, however it’s not clear what other examples of such accidents there are. Aquinas gives examples like eye color, bone structure, and natural temperament, but as noted above these seem less significant than gender. A question arises as to which principles of the individual (soul, or body, or both) bring these accidents about. This is addressed by his metaphysical classification in On Being and Essence.

Regarding the metaphysical classification, we note that the whole substance is the true subject of all accidents, but since humans are composed of two principles (form and matter) certain accidents flow more from form and others more from matter. Thomas describes four kinds of accident (two following from form primarily, and two following from matter primarily). First, of those following from form, rational activities — understanding and willing — occur entirely in the soul and have no share in matter (though there is a measure of dependence on the physical sense organs). “Other accidents following from form, like sensation, do have a share in matter since they properly reside in the composite substance. The soul, that is, originates powers of sensation but it can’t sense on its own.” “Moving downward, accidents following from matter will always have some relation to form since matter on its own is pure potency, uncharacterized by any feature.” So, in the third case, some accidents following from matter relate to a particular kind of form. For Aquinas, masculine and feminine are accidents that follow from matter but precisely in relation to an animal form. So when the animal dies, and the animal form is separated from the body, it is no longer gendered in a univocal way. Finally, “other accidents following from matter relate to a more general form, as one’s skin color occurs through matter’s relation to the form of some elemental mixture. The color thus remains even after the person has died.”

Combining the two accounts, Aquinas takes gender to be an inseparable accident following from one’s matter in direct relation to one’s substantial form as an animal. This helps us distinguish it from other inseparable accidents, as they would follow from one’s matter in direct relation to some form other than one’s animal substantial form. It seems that gender is the only example of this special class of inseparable accident we have, and so it is in this sense a metaphysically unique feature.

“Now, if being male or female relates necessarily to the form of an animal why does Thomas assigns gender’s origin to matter?” He gives two reasons:

First, for both Aristotle and Thomas, the male and female roles in generation are active and passive respectively. The male semen contains the formal principle of generation whereas the female seminal fluid contains the material principle, such that when the two come together a human is generated. Insofar as every act of generation is directed toward producing one’s likeness and since the male is more active is the generative act, the act naturally tends toward a male offspring, and a female results from an accidental alteration in the male semen. Since gender is determined by the manner in which the seminal matter has been affected, it is seen to follow from matter as opposed to form. Aquinas agrees that one’s reproductive power — as all powers — arise because of the soul, but the difference in gender is owed to a defect in the matter of the female (since the male, insofar as he is more active, has the more reproductive power more perfectly).

Second, for both Aristotle and Thomas since form is what makes matter to be a certain kind or species, a difference in form must result in a difference in species. Thus differences applying to individuals of the same species must be differences originating from matter.

Note that genders origination from matter does not mean that it has no bearing on the soul. “While the soul in its own right is not gendered, just as the soul on its own possesses no sensation, presumably the soul of a male can be derivatively considered a male soul and the same in the case of the female, since the soul’s identity is marked by it’s being the soul of a male or female body. One’s gender then, as following from the principles of the individual, characterizes the person as a whole.”

Brief evaluation of Thomas’s account (20:31-23:15)

Thomas’s logical classification of gender as an inseparable accident makes sense insofar as gender doesn’t apply to the species as a whole, but individual members. “Moreover, current biology’s understanding of genetic systems, chromosomal patterns, gonadal structures, and sexual organs affirms that the principles of the individual exercise permanent causation in their originating one gender or another.” In spite of this, the fact that gender seems to be in a class of its own — separate from other accidents — calls for further inquiry. And this inquiry would have to focus on Aquinas’s metaphysical account of gender arising from matter in relation to a specific form.

It’s not totally clear what it means for an accident to follow from the matter in relation to a specific form. If this is taken to mean simply that the accident flows from the principles of the individual as such, then it is well-taken since evidently, one gender is not a characteristic of the species. This would still leave open, however, which of the individual’s principles is at work here (soul, matter, or both). But Aquinas, in saying that the female gender arises from an accidental alteration of the semen, answers this second question. “That is, he holds not just that gender stems from the principles of the individual, but also that being male or female stems concretely from the side of one’s matter, rather than one’s substantial form or soul.”

Now, current biology, of course, has shown that the female reproductive abilities are not imperfect versions of the male ones. Man and woman, respectively, do not supply the active formal principle of generation and the passive material principle of generation. That a man’s production of semen and a woman’s ovulation each supply distinct elements of the offspring’s genetic material reveals that, in this capacity, the two are co-contributors to the offspring. Since man and woman do not relate generatively as perfect to imperfect it is not the case that any given act of generation seeks the male. As contemporary science shows, the male and female are equally intended at the biological level. So Thomas’s empirical reason for attributing gender to matter — the first reason I mentioned earlier — is no longer tenable.

This leaves us with the question of whether the second reason given still works. Is it true that gender must arise from the matter and not the form because the form cannot account for something that arises from the individual?

A revised account (23:16-36:42)

The aim here is to argue that the Thomistic principles suggest that gender flows more from substantial form than from matter, that is more from the soul than the body.

As both Aristotle and Aquinas saw, male and female are of a different category to black and white. The former are tied up with the essential teleos of the human being and contain the substance’s essence within their definitions, whereas the latter are not and do not. “The presence of an organ indicates a particular configuration of matter for the sake of one of the soul’s powers, which in turn flows from the essence of the soul. The soul itself arranges material structures as organs so that they might fittingly serve as means through which the soul’s various powers can operate effectively.” As Thomas says in The Disputed Questions on the Soul, “the soul constitutes diverse parts in the body even as it fits them for diverse operations.”

To unpack this we might say that like the vegetative powers the reproductive powers slowly manifest as the being matures, and as the soul actualizes and shapes the individual it constitutes these powers in particular organs within the body. Just like the sensory powers, if the soul were to leave the body so too would the generative powers. Unlike the sensory powers, however, not all humans share the same set of generative powers (instead we have something like a 50/50 split across the population).

The generative powers of man and woman should be considered, strictly speaking, co-generative, since they possess a two-fold formal object distinguished hierarchically. As “generative” they possess the same ultimate object, namely procreation of another human being. While as “co-” their proximate objects differ by way of offering distinct sexual organs and activities yet in relation with each other. The ultimate object of the co-generative powers points to the unity of nature shared by man and woman since another of the same species, whether male or female, is generated. The proximate object of the co-generative powers points to the distinction within human nature as found in either man or woman, albeit only at the level of the reproductive capacities.

Since the reproductive powers are two distinct co-generative — as opposed to one at varying levels of perfection — it seems clear that they must be accounted for by the substantial form of the individual. Of course, since the generative powers intrinsically depend on organs they would this should not be thought of as an attempt to separate the soul from the body, but rather to highlight the soul’s role in constituting the powers in the body. Thus we provisionally include gender in those accidents that stem from the soul and have a share in matter, as with the senses. In order to develop this account further, we address three objections.

The first objection is that modern biology seems to support Aquinas’s position that gender is better attributed to matter than soul. This is because modern biology teaches us that gender is intimately connected with various genetic networks, especially the chromosomal patterns XY or XX found in the zygote. But this does not so much entail that gender differentiation arises from matter primarily as show us more clearly how intimately related substantial form and matter relate to one another in the constitution of a human being. Any becoming of a substance requires appropriately disposed matter; after all, the being is generated by the actualization of potencies in the matter. But it is the resultant form (the actuality) that primarily characterizes the being the is generated.

The second objection comes from the second argument given by Aquinas above, that difference in form constitutes difference in species. Since men and women clearly share the same species, their difference must, therefore, arise from matter. Moreover, the notion of an individual brings forth — for Thomists at least — thoughts of matter insofar as it is the principle of individuation. But we must make a distinction between a universal form and a particular form. Aquinas grants that when a soul is commensurated to a particular body (that is, when they mutually limit one another so as to constitute an individual) in a sense it takes on additional characteristics, an obvious example being individuation even after separation from the body at death. It is inevitable that gender is of the form, since matter does not configure itself into particular organs (being indeterminate between any such configurations) it must be the soul that does so in and through matter “for the sake of the particular powers that work through those organs.”

The position I have argued affirms the notion that particular souls are essentially commensurated to particular bodies, but claims that within this commensuration gender begins at the level of the soul and is received into the corresponding matter accordingly designated by the genetic pattern.

As to the concern about this introducing a distinction between two species of human, we can say two things. Rather than being an additional power that future determines the essence of the individual, gender concerns the maintenance of the essence that the other powers constitute. “As oriented towards the species itself, [the generative powers] cannot in themselves constitute new species.” Second, as noted above gender is a co-generative power which differentiates it from the other powers given by the soul insofar as they are independent in some sense. They exclude each other in definition (“four-legged” excludes “winged”) or in fact (“scaled” excludes “feathered”). Gender’s nature, however, presupposes “one like itself” and so depends on and includes its contrary both in fact and in definition. Male is defined in terms of female and vice versa through the co-generative relation. The reproductive powers are not merely distinct as one sense is distinct from another, but as mutually dependent powers contributing to a single action (ie. generation). They are not to be understood as characterizing distinct species, then, but rather as integral parts of the same species considered at the reproductive level. (This is a consequence of us being social animals: humans are not wholly intelligible in terms of an individual, but require that that individual be understood in the context of some community. This reoccurs again at the higher level with powers that enable us to rationally cooperate, which are a consequence of us being political animals.)

The third objection takes issue with the description of co-generative powers. Why could we not accept that there is one generative power manifested in different ways, depending on the body to which the soul is united? This would entail that gender differentiation stems from matter as opposed to form. Note that this is much like Aquinas’s view insofar as he sees one power actualized to differing levels of perfection. Now in some sense, the objector is right, namely insofar as both generative powers have the same ultimate object. Because of this, they can be naturally grouped together, just as the various sensory powers can be naturally grouped together. But insofar as the generative powers have distinct proximate objects (their organs and activities), they can be distinguished. Interestingly, even in the woman, we see multiple generative powers in a single being: powers for generation, support, and nourishment of the offspring all of which are required for procreation (since the ultimate object of generative powers is a human and not merely a clump of flesh). Since there are really distinct generative powers, their distinction must arise from the substantial form and not the matter.

In order to affirm that a numerically single (that is, really identical) power to be differentiated only by matter, we would need to accept Aquinas’s account which, as we’ve seen, is falsified by modern biology. Otherwise, we’d need a “generic power” had by both male and female, which would need to be an abstract power or a power that includes both. But the first alternative is incoherent in Thomistic metaphysics (and even in much of modern metaphysics), and the second would involve an entire set of the person’s powers being denied and frustrated merely in virtue of them being an individual human. This “opposes Thomas’s thought and the majority of human experience.”

Being male or female, therefore, follows principally from one’s soul in relation to that soul’s correspondingly disposed matter.

Three ramifications (36:43-43:41)

The first concerns “gender’s status in relation to the person.” Gender is closely related to the person but is different from other such attributes. Other attributes (like free will, reason, soul, body, growth, and sensation) are understood when the human essence is abstracted from individuals and reproduction is like this. But it differs that when considered in itself the essence includes both male and female, but when it comes to exist there is a split into the co-generative powers. “The human essence in itself includes male and female; only a consideration of that essence as actually existent entails male or female.”

Turn, then, back to the metaphysical classification given above. We’ve seen that reproduction, like sensation, falls into the second category of those accidents which follow from form that have a share in matter. But given the differences between reproduction and sensation, there must be a real distinction within this category. The difference is between those accidents which flow from the nature itself, and those accidents which flow from the nature as it exists in this or that individual.

And in this sense, one’s gender is not as close to one’s fundamental humanity as are the other powers of the soul. Being man or woman — you might say — is more proper to the human individual than to the human individual. As Thomas would put it being gendered at all is proper to human nature, but being a man or a woman is proper to this instance of human nature, this soul and this matter.

All of the other accidents that flow primarily from the soul characterize the whole species, and so we call them the proper accidents (or properties), like sensation and risibility. But gender differs from the other individual accidents insofar as it characterizes one’s structure, abilities, and purpose. Insofar as the gender so characterises an individual we might say that it is “the primary attribute of the existing person”, not as something that constitutes the person (since this is given by the soul and matter), but as that which is most truly proper to individual person (so, in this sense, it’s like a property at the individual level).

The second concerns “gender’s status to the human essence or nature.” Man and woman are not distinct species of human nature, but nor are they merely individuals of human nature. It is good, therefore, to introduce some notions that can describe the genders with regards to their human nature. Man and woman are principles of the nature, they’re parts of it, they are ways of it existing or ways of a soul incarnating in a body, and they are relational as mutually fulfilling complements. “Thomas compares male and female to odd and even in the numerical realm.” But even this misses out the relational nature of humanity.

The third concerns “gender in its specifically human meaning as the intersection of eros and generation.” A slight modification of the Aristotelian definition of male and female is, “the male is what co-generates in another, the female is what co-generates in itself.” There’s nothing peculiar to humans here; we are gendered because we are animal. But human gender has richer meaning than non-human gender insofar as the procreative activity is integrally marked by rational choice.

By nature the generative act is a human act, and not just the act of a human. Thus, what is distinctively human in gender comes to light most manifestly in the “co-” dimension of the co-generative relationship to the extent that deliberation, choice, and love are integral moments within human sexual activity, which thus transcends merely instinctual limitations.

The distinctive human dimension of all this is one of the reasons that it is considered problematic if the human generative act occurs without proper mutual consent, since it “presents a co-generative act with the co- aspect as distinctively human. Since the entire act is co-generative, if one aspect lacks distinctively human structure, so does the whole.” That the co- aspect is human and therefore higher than mere biological generation, it elevates the generative aspect which is primarily animal. The biological tendency becomes subsumed into a conscious intention in love.

Further, as Thomas points out, generating another like oneself in the case of a human involves continued rational and affective dimensions beyond those of the sexual sphere, since the mature human only comes to be after an extensive period of support, nourishment, training, education, and love.

Beyond metaphysics (43:42-46:55)

Here we comment on some things beyond the metaphysical question but which depends on the metaphysical answer, namely issues in the psychological, social, and ethical realms. There are two putative objections that might be raised from modern concerns against the claim that gender stems from the soul. First is the issue of sex-reassignment surgery, second is the reality of intersex persons.

With regards to the first, if in fact sex-reassignment surgery actually changed one’s sex/gender then it would constitute a concern. However, even if such surgery can change the outward appearance of an organ it nonetheless leaves the patient sterile. So rather than say that one’s gender has changed it is more accurate to say that it has to some degree been lost (or blocked).

With regards to the second, just as with sensation defects and abnormalities are possible so too with gender. This arises from the fact that gender (like the senses) arises from the soul working in and through matter. “Aside from the assistance of medical technologies in such cases, it’s crucial to recall that one’s gender, though integral to the person, is neither the defining nor the most important aspect of the person.” To quote Thomas on the place of gender in human life:

Among animals there is a vital activity nobler than generation to which their life is principally directed. Therefore the masculine sex is not in continual union with the feminine in perfect animals, but only at the time of coition, so that we may consider that through coition male and female are made one. But [humans are] further ordered to a nobler vital activity, which is to understand. Therefore there had to be a greater reason for the distinction of these two forces in [them], so that the female should be produced separately from the male and yet they might be fleshly joined as one for the work of generation.

In commenting on this, John closes with:

The ultimate telos of a human being involving the flourishing of a life suffused with knowledge and love reminds us that relationality and fruitfulness occur in realms higher than the physical. If, with Aristophanes in the Symposium, one were tempted to picture the human being simply as a longing half, the passage just quoted offers a larger view. In his own way, Thomas calls to mind Socrates’ and Diotima’s assent to the beautiful.

Contrastive probabilistic explanation

I want to propose something I’m not totally convinced is correct, but that I think is worth considering. In general we have the question about contrastive indeterministic explanation: an antecedent A can give rise to two different consequences B and C, it actually gives rise to B, and we want to know why it gave rise to B rather than C.

There are two cases that encode this, each prima facie in different ways (though they may be ultima facie reducible to the same case, more on this later): libertarian free choice and quantum indeterminism. Let’s take them in turn.

In a free choice we are impressed by reasons R for choosing between B and C. In the event we choose B, we want to know what explains why we chose B rather than C. The answer comes in being more precise about the content of R: it includes reasons R1 for choosing B over C and R2 for choosing C over B, and it’s in virtue of this that we are choosing between B and C in the first place (see section 4 in Divine Creative Freedom by Alexander Pruss). When we choose B then R1 explains why we chose it over C, and when we choose C then R2 explains why we chose it over B. Thus, the explanation is contrastive in virtue of the reasons themselves being contrastive. We’ll return to this shortly.

In an event of quantum indeterminism we have some quantum event — radioactive decay, say — that happens with a certain probability. Let A be the circumstance involving an atom at t1 which will decay with some probability, B be the circumstance involving it having decayed at t2, and C the circumstance involving it not having decayed at t2. In B, how would we explain why it had decayed rather than not?

The first Aristotelian step is to give an account of probabilistic causation, and the second is to elucidate the explanation this affords us. With regards to the first, something like what Feser has proposed here seems plausible, namely that the probabilistic behaviour the atom exhibits is grounded in its substantial form. This explains why the atom in the same antecedent state can result in two different consequent states, in a similar way to how the form of a material thing explains its inertia (see Nature and Inertia by Thomas McLaughlin for a fantastic discussion of this). It also plausibly explains why B is realised when it is realised. But it does not seem to explain why B was realised rather than C.

And here comes my proposal: there is no contrastive fact over and above the plain fact that B occurred and C did not. The difference between the two cases is a relation, and a relation is wholly grounded in the relata themselves (see Aquinas on the Ontological Status of Relations by Mark Henninger). Thus to explain why I am taller than you, it is sufficient to explain why I am my height, why you are your height, and note that the former is greater than the latter. There is no additional fact to explain. Similarly to explain B, and note that B excludes C, is sufficient to explain why B rather than C. If the situation were slightly different such that we had two identical atoms at t1 that at t2 realised B and C respectively, then to explain B for the first and to explain C for the second just is is to explain the outcome of the difference, since this consists precisely in the two outcomes being realised.

But wait! Why was there some irreducible contrastive fact to explain in the free choice case? Because in this case the content of the choice itself was contrastive. It was not that the relation between the choices had to be explained contrastively, but rather that in order to explain every aspect of the choice we also had to explain the contrastive aspects.

Lonergan on Aquinas on Causation

Below is an excerpt from Bernard Lonergan’s incredible book Grace and Freedom, discussing Thomas Aquinas’s views on causation and how they relate to Aristotle’s views on the topic. Except for the term “actio” I’ve replaced Latin phrases with their English translations in square brackets.

Causation is the common feature of both operation and cooperation; its nature is of fundamental importance in this inquiry. But if St Thomas certainly disagreed with Hume, who held causation to be purely subjective, it is less clear what object he considered to constitute the objective reference of the proposition “A causes B.” Was causation for him something in between A and B? Or was it simply the relation of dependence of B on A? Or was it some entity added to A as actually causing? Let us take each of these three views in turn.

As to the first view, that causation is in between cause and effect, St Thomas constantly and explicitly denied it in the case of divine activity. Avicennist biology had distinguished between a [a moving power commanding (something)] and a [a motive power effecting (something)], and St Albert had drawn a parallel distinction between the [divine created power] and a [divine uncreated power]. But St Thomas, while he used the biological opinion at least in his commentary on the Sentences, always asserted that God was his own virtue, operated without any mediating virtue, indeed operated [by the immediacy of power]. The matter is less clear with regard to causation by creatures. Even in later works there is a variety of expressions which appear to imply something in between agent and recipient. Still, it should seem that these are but modes of expression or of conception; for what is in between, if it is something, must be either substance or accident; but causation as such can hardly be another substance; and if it were an accident, it would have to be either the miracle of an accident without a subject, or else, what St Thomas denied, an accident in transit from one subject to another.

On the second view, causation is simply the relation of dependence in the effect with respect to the cause. This is the Aristotelian position presented in the Physics and explained by St Thomas as follows. First of all, this analysis prescinded from the case of the mover being moved accidentally; for instance, a terrestrial body acts through contact and cannot touch without being touched; but this does not prove that the cause as cause undergoes change but only that the terrestrial body as cause does so. In the second place, it was argued that the emergence of a motion or change involved the actuation of both the active potency of the cause and the passive potency of the effect. In the third, place the thesis was stated: one and the same act actuates both potencies, and this act is the motion produced in the object moved. Fourthly, there came the ground of this position: if causation, actio, were an entity inherent in the cause, then, since it is a motion, it would follow either that “[every moving thing is moved],” or else that motion inheres in a subject without the subject being moved; but the latter is contradictory, and the former would preclude the idea of an immovable mover; therefore, causation is not inherent in the cause but in the effect. Finally, the objective difference between action and passion was explained: both are really identical with the motion of the recipient; they differ notionally, for action is this motion as from the cause, [movement of this as from this], while passion is the same motion as inhering in the effect, [movement of this as in this].

It would seem that St Thomas accepted this Aristotelian analysis as true and did not merely study it as a detached and indifferent commentator. Not only did he repeat the same exposition in commenting the parallel passage in the Metaphysics, while in the De anima he argued that sound and hearing, instances of action and passion, must be one and the same reality, else every mover would be moved; but in works that are entirely his own the same view at least occasionally turns up. In the Summa theologiae the definition of actual grace appeals to the third book of the Physics for the doctrine that “[an act of a mover is a movement in the thing moved]”; the analysis of the idea of creation was based upon the Aristotelian identification of action and passion with motion; and the fact that this identification involved no confusion of action with passion was adduced to solve the object against the Blessed Trinity, namely, that since the divine Persons were identical with the divine substance they must be identical with one another. Still, this is not the whole story. In his commentary on the Sentences St Thomas brushed aside the notion that action and passion were on and the same reality, while in the parallel passage in the Summa theologiae a solution is found that does not compromise the authority of Aristotle. This difference involves a change attitude, prior to the Pars prima and perhaps posterior to the De potentia, raising the question of the initial Thomist view.

In earlier works, then, the theory of causation seems to have been worked out on the analogy of the familiar distinction between the [being towards] and the [being in] of the relation. In action one has to distinguish between a formal content described as [from an agent] or [as proceeding from an agent to another], and on the other hand, a reality, substantial or accidental, termed the [principle of action] or the [cause of action] or even loosely actio. This terminology is to be found no less in the commentary on the Sentences than in the De potentia, but at least in the latter work it also is quite clear that the formal content is no more than a notional entity. In the two passages quoted below, the reader will be able to verify the following six propositions: (A) change from rest to activity is change in an improper and metaphorical sense; (B) the reverse change from activity to rest takes place without any real change in the agent; (C) when the agent is acting there is no composition of agent and action; (D) what remains unchanged is the [principle] or [cause of action]; (E) what comes and goes without changing the agent is the formal content, [from an agent]; (F) the analysis holds even in the case of a created agent such as fire.

And so a relation is something inhering (in a subject), though that does not result from the mere fact that it is a relation; as action, too, from the fact that it is action, is considered as from an agent, but as an accident it is considered as in the acting subject. And therefore, there is nothing to prevent an accident of this kind (B) from ceasing to be without (involving) a change of that (subject) in which it is, because its being is not realized insofar as it is in that subject, but insofar as it passes on to another; with the removal of that (passing on), the being of this accident is removed (E) in what regards the act but remains (D) in what regards the cause; as is the case also when, with the removal of the material (to be heated), the heating (F) is removed, though the cause of heating remains (De potentia, q. 7, a. 9, ad 7m)

But that which is attributed to something as proceeding from it to something else does not enter into composition with it, as (C) neither does action (enter into composition) with the agent… without any change in that which is related to another, a relation can cease to be through the change alone of the other; as also is clear about action (B), that there is no movement as regards action except metaphorically and improperly; as we say that (A) one passing from leisure to act is changed; which would not be the case if relation or action signified something remaining in the subject (Ibid. a. 8 c.)

If our interpretation of these passages is correct, then at least in the De potentia St Thomas had arrived at a theory of action that was in essential agreement with Aristotle’s. Evidently the two terminologies differ completely: on the Aristotelian view action is a relation of dependence in the effect; on the Thomist view action is a formal content attributed to the cause as causing. But these differences only serve to emphasize the fundamental identity of the two positions: both philosophers keenly realized that causation must not be thought to involve any real change in the cause as cause; Aristotle, because he conceived action as a motion, placed it in the effect; St Thomas, who conceived it simply as a formal content, was able to place it in the cause; but though they proceed by different routes, both arrive at the same goal, namely, that the objective difference between [to be able to act] and [to actually act] is attained without any change emerging in the cause as such.

This real agreement in terminological difference solves the problem of St Thomas’s thought on causation. John of St Thomas listed the passages in which action is placed, now in the agent and now in the recipient; from this he drew the conclusion that action, according to St Thomas, was inchoatively in the agent and perfectively in the recipient. But in point of fact St Thomas simply had two ways of saying that action involved no new entity in the agent; and so far was he from differing really from Aristotle that he seems to have been quite unaware of even his terminological departure from the Aristotelian position. This latter fact not only solves Cajetan’s perplexity over the apparent divergence between the commentary on the Physics and regular Thomist usage but also provides the most conclusive evidence against such as position of Billuart’s that a real distinction in the agent between [power to act] and [the act itself] is one of the pillars of Thomist thought.

Virtual existence

It might not seem like it, but a proper understanding of virtual existence can be significantly helpful when trying to understand the structure of human communities. To this end, I’d like to spend some time thinking about this puzzling notion here.

Substances and aggregates again

You’ll recall that, in our discussions about substantial activities, we spent a fair amount of time introducing the notion of substance. There we said that a substance is something which has intrinsic directedness towards an end, or equivalently something which has intrinsic causal powers.

The guiding intuition here is that when a substance does something it is the substance itself doing it, as opposed to its parts or something external. So, the doing is intrinsic to the substance as opposed to its parts or something outside. Now, we use the term characteristic behaviours to pick out what something does always, or for the most part, given the kind of thing that it is; that is, how it behaves so long as it’s not being “blocked” in some way. Plants and animals grow to become healthy adults unless prevented by genetic defect or environmental factors, hydrogen combusts under certain circumstances unless prevented, the phosphorous in a match head will ignite when struck unless prevented, and so on.[1] We mentioned before that the only way such characteristic behaviours can be made intelligible is in terms of that thing’s being directed toward that behaviour by virtue of the kind of thing that it is. And this directedness, you’ll recall, needn’t be the result of conscious deliberation.

Putting this all together we get that if the doing of something always or for the most part is intrinsic to a thing, then so is the directedness towards this behaviour. Similarly, since a thing can’t do something without the power to do it, if the doing of something is intrinsic to a thing then so are the causal powers needed to do it. It is roughly along these lines that we (following Aristotle and the Scholastics) come to understand substances in the terms mentioned above. For a longer discussion of this, as well as responses to objections, I suggest you read Edward Feser’s Scholastic Metaphysics.

In contrast to substances, aggregates are those things which have only extrinsic directedness or causal powers. That is, an aggregate’s causal powers are reducible to the sum of the causal powers of its parts and what is imposed on it from outside.

A pile of rocks would be an obvious example of an aggregate. Its power to hold something 2 meters above the ground is merely the sum of the individual rocks that make it up. Above Aristotle used an example of a bed, which is merely an aggregate of the materials (wood and metal) that make it up.

Some aggregates, because of their complexity, are less obviously aggregates. Examples of these are things like watches and computers. A watch’s power for time-telling is imposed on it by us, and its power for the circular motion of its hands is merely the sum of the powers of its parts such as the conduction of electricity and so on. Similarly for a computer or a calculator.

The pile of rocks would be a table to the extent that it is intended as such by the individual or community that has access to it. Here it would be the sum of the parts together with an outside intention that make the pile of rocks a table.

With the watch there is nothing intrinsic to it or its parts that enables it to tell the time. This is something derived from us on the outside, as interpreters of the mechanical symbols we used in the watch’s construction. If you took us out of the equation, all that would remain are cogs, electrically stimulated, moving other cogs and pieces of metal at a fairly constant rate.

I suspect this is less clear to many of us in the case of computers. But this is more a function of our ignorance about how computers work than anything substantial about computers themselves. In this case various electrical components alternate their charges by interacting with one another, typically terminating in patterns of colours on a screen or sounds from a speaker. Sure, we’ve managed to do this faster and with smaller components, but there is nothing of significant difference (at least not for our purposes) between this and purely mechanical computers. We impose meaning on these patterns of colour and sound, and thereby impose on the computer the ability to compute things that are not intrinsic to the metal or electrical currents themselves. This is not unlike we impose material symbols and utterances with meaning in written and spoken communication.

Now, between substances and aggregates the substances are more ontologically fundamental. Or, as it has been put, substances are the most fundamentally real things. Of course, both aggregates and substances depend on their parts, but (1) aggregates are always made up of substances, and (2) with substances there is also a sense in which the parts depend on the whole. A full examination of (1) will require a deeper understanding of per se causal chains than we have space here to discuss so, as before, we’ll put this off until another time. We will spend the rest of our space here attempting to make inroads to understanding (2). Throughout these attempts we will being using the insight that what a thing is (its nature) is closely tied up with its directedness, characteristic behaviours, and causal powers. Indeed, we said last time and have noted elsewhere, that a thing’s nature just is what it is directed towards.

The actual existence of parts in aggregates

Now, an aggregate’s causal powers and directedness are by definition not intrinsic, but rather extrinsically derived from its parts and from outside. Thus we find that aggregates don’t really have a nature or existence over and above the substances that make them up and the ends imposed on them from outside. That is, their nature and existence are wholly reducible to extrinsic sources, and it is therefore by reference to these extrinsic sources that these aggregates are intelligible.

Furthermore, the substances that make up (or impose on) an aggregate retain their intrinsic directedness, characteristic behaviours, and causal powers. We use the term “actual existence” to refer to the way in which these substances exist, and say that they are “actually present” in (or around) the aggregate.

This is consistent with saying that, by virtue of being part of an aggregate these substances have their characteristic behaviours and causal powers influenced by one another. In this case they don’t take on new behaviours or powers, but rather have their behaviours and powers redirected through interaction with one another. Think, for instance, of how cogs influence each other in mechanical clocks or how pipes redirect the flow of water.

The virtual existence of parts in substances

What can we say, then, about parts of substances? A substance does have a nature and existence over and above its parts and outside imposition. It’s nature and existence are not wholly reducible to extrinsic sources, and it is therefore to some extent intelligible apart from these extrinsic sources. At this point we must tread carefully, for it is easy to misunderstand what is being said. In the interest of clarity, then, we make a distinction: a part of a substance can be considered in two ways, either (1) in itself or (2) as a part. In the former case we consider the part in isolation from the substance it belongs to, and in the latter case we consider the part in the context of the substance it belongs to.

We can illustrate this distinction with some examples. A previously mentioned example of a substance was a water molecule. We pointed out that “water boils at 100°C while hydrogen, considered in itself, boils at -252.9°C and oxygen, considered in itself, boils at -183°C.” On the other hand, hydrogen and oxygen, considered as a parts of water, boil at 100°C. In some ways this is obvious, for the continued existence of the water depends on the continued existence of the hydrogen and oxygen that make it up, and since water doesn’t combust when it comes into contact with fire it follows that neither do its parts. On the other hand, I’m sure that for many of us hearing something like “the boiling point of hydrogen is 100°C” causes somewhat of a knee-jerk reaction. In a way this highlights the point of the distinction. Presumably we have such knee-jerk reactions because of what we learnt in chemistry class. But chemistry, like many sciences, seeks primarily to understand the essential features of the objects it studies, and therefore typically studies these objects in isolation from outside influence. They therefore have little to say about these objects when considered as part of another. So such knee-jerk reactions are neither surprising nor hindering to our discussion.

Another example of a substance previously mentioned was an animal. For each of the organs an animal has we can consider it in itself or as a part. In this case we typically have the reverse intuitions as above: with the molecules we are accustomed to thinking about them in themselves, but with organs we are accustomed to thinking about them as parts. Consider, for instance, the claims “hydrogen boils at -252.9°C” and “the heart pumps blood”. The former tells us how hydrogen behaves in isolation from outside influence, and the latter tells us what the heart does in the context of the rest of the body. Now, considered in itself, “an organ is merely a clump of flesh which decomposes if left to its own devices.” Indeed, don’t we see this all the time with severed limbs and corpses? On the other hand, considered as parts organs “are each capable of their individual functions in the body (walking, grasping, thinking, sensing, pumping blood, and so on) and they are all capable of participating in the life of the animal”, where by “life” we mean the ability of a thing to “produce, conserve and repair its proper functioning as the kind of thing it is”. For example, compare what happens when you cut a severed hand (or some other non-living thing) and when you cut a living thing. The latter will repair itself to some extent whereas the former will do nothing.

You’ll notice from the examples given that the characteristic behaviours, directedness, and causal powers of things can differ quite significantly depending on whether we’re considering them in isolation and or as parts. Therefore, so do their natures: a clump of flesh is a significantly different kind of thing to a heart pumping blood, a free hydrogen atom is a different kind of thing to a hydrogen atom in a water molecule, and so on. An implication of this is that the things considered in themselves are not actually present in the substances they belong to, at least not in the same sense that the things considered as parts are. In these cases, we say that the things in themselves are “virtually” present in the wholes they belong to.

What of the parts considered as parts? They are directed by the nature of the substance and derive their causal powers from the substance. I don’t mean that the substance is something separable from its parts, for of course it is constituted by them. Rather, it is on account of the parts being configured together so as to produce a whole which is capable of more than the mere sum of its parts, each considered in itself, that the parts cease to behave like they would in isolation and take on a new nature grounded in the overall configuration itself. It is because of this configuration of the substance that the parts have different causal powers, behaviours, and directedness. It is in this sense that the parts all together take on the nature of the substance and share in it’s existence. And it is this sense that parts depend on the substance they belong to.

A hylomorphic account of virtual existence

Let’s summarise what we’ve said so far. In aggregates the parts considered in themselves actually exist, since they continue doing what they do in isolation. And although they continue behaving as they would in isolation, they can nonetheless have this behaviour redirected by the other parts of the aggregate. Finally, in aggregates there isn’t really a distinction between the parts considered in themselves and the parts considered as parts.

In substances the parts considered in themselves virtually exist, since they do not continue doing what they do in isolation. By virtue of how they are configured in the substance, they behave in a new ways which share in the existence of the substance. Finally, in substances there is a distinction between the parts considered in themselves and the parts considered as parts.

Now, we might be tempted to see the word “virtual” and think that what’s being claimed is that the parts of substances, considered in themselves, do not make any causal contribution to the substance they belong to. On the contrary, Scholastics call this “merely logical” existence and distinguish it from virtual existence. Something has merely logical existence when its existence is wholly dependent upon intellectual activity. Examples would be fictional stories, imaginary friends, hallucinations, and dreams. On the other side of the spectrum are substances, which, as we’ve been saying, have actual existence. In this context this entails that they “fully” exist independently of intellectual activity. Virtual existence sort of stands in between these two opposites: to some extent they have mind-independent existence, and to some extent they are dependent upon intellectual activity. This may sound slightly strange, but this conclusion is implicit in what we’ve been saying. Their partial dependence on intellectual activity derives from the fact that while they are part of a substance they do not behave as they do in isolation, and so it requires intellectual activity to “fill in” what’s currently absent. Their partial independence of intellectual activity derives from the fact that the parts could not be configured so as to constitute the substance unless they were as they are in themselves. For instance, it is precisely because of how hydrogen and oxygen molecules are in themselves, that they can come together to form a water molecule.

We can shed some light on this somewhat strange property of virtual existence by means of the Aristotelian theory of hylomorphism.[2] According to hylomorphism every material thing is composed of “form” and “matter”, where by matter we mean some otherwise indeterminate substratum and by form we mean the configuration of the matter that determines it to this rather than that. So stated, hylomorphism is completely general, and we illustrate it with three very different cases.

First, there’s the sense in which we’re talking about material substances like trees, dogs, humans, water molecules, wood, and so on. Our matter is the “stuff” we’re all made out of, and our forms are the configurations of this matter into the various kinds of material things there are. We humans have our matter configured in a way quite differently from how the matter in the tree outside or in my pet cat is configured. It is on account of these different forms that we have our distinctive behaviours, directedness, and causal powers, and on account of which we are called humans, trees, and cats.

Second, there are things like written or spoken sentences or pieces of music. With the sentence the matter would be the words or letters and the form would be the syntax together with some kind of “semantic coherence” (since syntax alone isn’t enough). With the music we have something similar, but I suspect there syntax is enough.

Third, there are actions. Here, I think, is where we begin to see the generality of the form-matter distinction. Consider the motion of my hand into your face. This movement itself is indeterminate between at least two possibilities: either I am punching you or I am doing something else and have hit you by mistake. As such, the movement is the matter of my action. What is the form? Surely it’s my intention. If I intend to hurt you then the action is me punching you, otherwise it is a mistake. So, while the form-matter distinction primarily applies to material substances, at the end of the day it goes far beyond this to almost everything.[3]

Now, using the form-matter distinction we can say the following. Something merely logically exists if it has neither form nor matter in reality, but is only understood or imagined in such terms. Something actually exists if it is constituted by the composition of form and matter which are intrinsic to it; that is, the thing is made up of its own form and matter. And something virtually exists if it is constituted by the composition of intrinsic matter and extrinsic form; that is, the thing contributes its matter to the form of something else, or equivalently the thing’s matter is informed by something else.

This captures, in the technical jargon of hylomorphism, what we were talking about earlier with the parts making contribution to the configuration of the substance and thereby participating in its existence. It also enables us to make sense of the partial dependence of virtually existing things on intellectual activity: such activity is necessary to “fill in” the missing intrinsic form, but not the matter.


  1. We’ve spoken about these kinds of generalisations before, at which point we called them “Aristotelian categoricals”. John Haldane, in his talk Aquinas and Realism, calls them “generics”. David Oderberg, in his paper Essence and Properties, calls them “properties”, along with Scholastics more generally.
  2. We won’t be able to do complete justice to the theory now, so if you’re interested in more than what I have to say here I recommend all the resources I’ve listed on my resources page under the sections “Hylomorphic dualism” and “Hylomorphism in general”.
  3. One might be tempted to equate form and structure. While in some cases these are the same (music pieces, for example), this is not true in general. See David Oderberg’s paper Is Form Structure? for a more detailed discussion of this.

Substantial and aggregate activities

In the Physics Aristotle gives his famous definition of a substance, which he refers to as a thing that “exists by nature” or as a “natural object”:

Some things exist by nature, others are due to other causes. Natural objects include animals and their parts, plants and simple bodies like earth, fire, air, and water; at any rate, we do say that these kinds of things exist naturally. The obvious difference between all these things and things which are not natural is that each of the natural ones contains within itself a source of change and of stability, in respect of either movement or increase and decrease of alteration. On the other hand, something like a bed or a cloak has no intrinsic impulse for change — at least, they do not under that particular description and to the extent that they are a result of human skill, but they do in so far as and to the extent that they are coincidentally made out of stone or earth or some combination of the two.

The nature of a thing, then, is a certain principle and cause of change and stability in the thing, and it is directly present in it — which is to say that it is present in its own right and not coincidentally. (Physics II.1 192b8-b23)

Edward Feser summarises this definition from Aristotle by saying,

The basic idea, then, is that a natural object is one whose characteristic behavior — the ways in which it manifests either stability or changes of various sorts — derives from something intrinsic to it. (Between Aristotle and William Paley: Aquinas’ Fifth Way)

Aristotle and the Scholastics would later argue that the only way to make sense of the fact that things always, or for the most part, behave in certain ways is if they are by nature directed towards such behaviour. That is, if they have an inherent tendency or directedness towards such activity as an end. (cf Physics II.8 198b34-199a7) This intrinsic directedness towards an end, then, is the nature of thing:

The point is that those things are natural which undergo continuous change, starting from an intrinsic source of change and concluding at a particular end… it is clear that a thing’s nature is a cause, and that it is the kind of cause I have been saying — namely, purpose. (Physics 199b15-18, 32-33)

It must be recalled that neither Aristotle nor the Scholastics who followed him thought of this directedness or “purpose” as necessarily involving intelligence or deliberation from the things so directed.

This is particularly clear in the case of non-human animals, whose products are not the result of skill, enquiry, or planning. Some people are puzzled by how spiders, ants, and so on make what they make — do they use intelligence, or what? … It is ridiculous for people to deny that there is purpose if they cannot see the agent of change doing any planning. After all, skill does not make plans. If ship-building were intrinsic to word, then wood would naturally produce the same results that ship-building does. If skill is purposive, then, so is nature. (Physics II.8 199b26-30)

Again, Feser explains:

In other words, that goal-directedness does not require conscious deliberation is evident from the fact that a skilled craftsman can largely carry out his work without even thinking about it—”on autopilot” as we might put it today, or without first “making plans,” as Aristotle puts it. But if this is possible for someone with such skill, there is in Aristotle’s view no reason not to think it also possible for natural objects. This is the force of the ship-building example: If there were something in the very nature of wood that “directed it” toward the end of becoming a ship, then what in the case of human craftsmanship results from deliberate design — a ship — would in that case result “naturally” instead, that is, without conscious deliberation at all. Indeed, “it looks as though things happen at the plant level too which serve some purpose” in just this way, even though plants do not deliberate — for instance, an oak derives from an acorn without the acorn planning this result — and there is also of course the example of “non-human animals, whose products are not the result of skill, enquiry, or planning.”

So substances are those things which have an intrinsic directedness towards an end. Because this directedness is tied up with a thing’s characteristic behaviours, and characteristic behaviours are tied up with a thing’s causal powers, we might equivalently say that substances are those things which have intrinsic causal powers. By intrinsic, here, we mean that the directedness or causal powers of the thing are not (1) imposed from some outside agent or (2) reducible to the sum of the its parts considered in themselves. Aggregates (or “heaps”), on the other hand, have only extrinsic directedness or causal powers.

Let’s consider some examples of each. On a molecular level, a water molecule is a substance, for it has causal powers which are not reducible to the powers of its parts. For instance, water boils at 100°C while hydrogen, considered in itself, boils at -252.9°C and oxygen, considered in itself, boils at -183°C. The same goes for other powers.

On a more macroscopic level, individual animals are substances. Considered in itself, an organ is merely a clump of flesh which decomposes if left to its own devices. However, when the organs co-exist in an animal they are each capable of their individual functions in the body (walking, grasping, thinking, sensing, pumping blood, and so on) and they are all capable of participating in the life of the animal, where life is:

… the natural capacity of an object for self-perfective immanent activity. Living things act for themselves in order to perfect themselves, where by perfection I mean that the entity acts so as to produce, conserve and repair its proper functioning as the kind of thing it is… (David Oderberg, Teleology: Inorganic and Organic)

Consider, for instance, how you develop from a baby in your mother’s womb to a fully-grown adult, or how body heals itself when damaged, or how you don’t just decompose (unless you’re sick in some way). None of your organs, considered in themselves as mere clumps of flesh, are capable of these things and so you are not merely the sum of your organs.

A pile of rocks would be an obvious example of an aggregate. Its power to hold something 2 meters above the ground is merely the sum of the individual rocks that make it up. Above Aristotle used an example of a bed, which is merely an aggregate of the materials (wood and metal) that make it up.

Some aggregates, because of their complexity, are less obviously aggregates. Examples of these are things like watches and computers. A watch’s power for time-telling is imposed on it by us, and its power for the circular motion of its hands is merely the sum of the powers of its parts such as the conduction of electricity and so on. Similarly for a computer or a calculator.

From wholes to activities

All this is by way of introduction for what I really want to talk about here. The space was not wasted, however, for what we have introduced will serve us well in what follows. Thus far we’ve been discussing the distinction between substantial and aggregate wholes. My aim here, however, is to make a parallel distinction between substantial and aggregate activities.

A substantial activity, then, is one which has intrinsic directedness towards an end. That is, its directedness is not (1) imposed from some outside agent or (2) reducible to the sum of the its parts considered in themselves. In order for us to understand this we need to be clear on how an activity has directedness, and the best way to achieve such clarity is by considering how substances engage in activities. For our purposes here, it will be sufficient to distinguish between three groups of substances: non-animals, non-rational animals, and rational animals.

By non-animals I mean inorganic substances (rocks, water, atoms, …) and non-animal organisms (that is, vegetation). What distinguishes animals from non-animals is that the former have some form of sentience (and, typically, an ability for self-movement). Since non-sentience involves not being able consciously move to an end it seems we have two options with regards to how activities involving non-animals have directedness: either their activities don’t have directedness, or the directedness of their activities derives from the directedness the substance has in virtue of its nature.

What distinguishes rational animals from non-rational animals is that the former have the ability to (1) abstract universal concepts from particulars (“Socrates is a human“), (2) combine these concepts into judgements or propositions (“All humans are mortal”), and (3) string these propositions into arguments for conclusions (“Therefore, Socrates is mortal”).[1] So within animals we distinguish between non-rational animals, which are only conscious of particular things via sensation, and rational animals, which are additionally conscious of the universal concepts that pervade all the particulars. By virtue of their consciousness animals are capable of directing their actions towards specific ends in addition to the ends set for them by their natures.

For instance, a cat is by nature directed towards certain characteristic activities such as walking on four legs and eating certain types of food, as well as developing such morphological features that make these possible. However, because this cat is hungry and conscious of that bird it directs and moves itself towards that bird in order to eat it. All the while, however, the cat is not conscious of universal concepts (as such) like “being hungry”, “birds” and so on. Much of its “reasoning” is driven by instinct and nature. But this does not invalidate the claim that it has a measure of self-direction which it derives from its consciousness of particular things. Rational animals, because they are also aware of universal concepts, are capable of directing themselves in accordance with a richer set of ends.

The Porphyrian tree for corporeal substances. Leaf nodes represent species and edges represent specific differences that divide each genus up.
The Porphyrian tree for corporeal substances. Leaf nodes represent species and edges represent specific differences that divide up each genus.

Whether an animal is rational or not, ultimately its intention is what determines the direction of a given activity. Consider, for instance, the movement of my hand into your shoulder. What I intend to achieve with the movement is what determines whether this action is me punching you or merely an accident (which would be the case if I was intending to get something else and misjudged our relative positions).

With these distinctions in hand we ask the following question: how are substantial and aggregate wholes related to substantial and aggregate activities? It seems obvious that substances are capable of substantial actions and aggregates are capable of aggregate activity. But does this exhaust the possible relations?

The possibility of substantial activity by aggregate wholes

There are only two other options we could consider. The first is substances performing aggregate activities, but in the interest of time we’ll leave this to one side.

The second option is that of an aggregate performing a substantial activity. Such an activity would require an aggregate of substances to direct their otherwise disparate activity toward a common end. Is this not what we find in various teams and associations throughout human society? A sports team works together to win the game, an orchestra works together to play their piece well, the various employess in a company work together for the sake of the company, the various military personnel work together to achieve victory in war, when two friends pick up a large object together, and so on.

At this point we must be careful, lest we fall into error and think some such activities substantial when in fact they are merely aggregate. Take the example of the members of an orchestra performing their piece. This is an example of substantial action because each intends to contributes to the same performance. It’s this shared intention (or something like it) that makes the activity substantial, and not just that the sound produced is a combination of the sounds of the various instruments. After all, even aggregates involve combinations of their parts. By contrast, consider the musicians behind stage before the performance starts, while they each tune their respective instrument. An observer standing backstage will hear the combination of all the various sounds they make as they do this. The making of this combined sound will be merely an aggregate activity. Why? Because there is no shared intention directing the musicians to a common end. Rather, in this case each musician intends merely to tune their own instrument independent of the others. So when we aggregate the various tuning activities we end up with an aggregate of ends and therefore an aggregate activity.

So aggregate wholes can indeed engage in substantial activities, and they do so when and only when the members of the aggregate intentionally work together toward some common end.

But we can take this further. You’ll notice that the examples I listed above all involved aggregates of rational animals. This was not accidental, for only aggregates of rational beings are capable of this kind of substantial activity we’re considering. We see why when we reflect on what’s involved in working together with others toward a common end.

First, working together involves recognising both you and another falling under the same category of “part” in some sense. It requires that we understand the roles we’re responsible for and how those roles contribute to the achievement of the end in sight. Often (if not always) this will require that we understand the rules which encode our responsibilities. All of this, and more, requires a capacity for being conscious of universal concepts like “part”, “whole”, “role”, “responsibility”, “rule”, “expectation”, and so on. Since only rational beings are conscious of universal concepts, it follows that only rational beings can work together toward a common end.

Second, working together toward a common end requires that we be conscious of the end as common. Briefly, common ends are ends that can be enjoyed by multiple members without thereby being diminished. They are opposed to private ends, which are always diminished when shared.[2] For instance, if there is a loaf of bread between me and someone else, the more the I eat the less there is for the other person to eat. Siblings will know that the time I spend playing on the computer is time my brother cannot play on the computer. Consider, however, the examples we mentioned earlier: winning a sports game, the musical piece, the good of a company, victory in war, the picking up of a car. All of these are shared amongst the members in the corresponding aggregate, but are not thereby diminished. The same victory in war, for instance, is equally had by everyone in the winning nation.

Now, from the examples given it seems clear that particular things (or combinations of particular things) considered as particular can only serve as private ends. By contraposition, it follows that in order to be conscious of an end as common requires that we be conscious of universal concepts. Therefore only rational beings can be conscious of, and direct themselves toward, common ends.


  1. The Scholastics called these the “acts of reason”, and labeled them (1) grasping, (2) composition and division, and (3) reasoning. Each of the acts of reason are dependent upon the earlier ones for their operation. Technically, (2) is richer than merely the ability to form propositions: it also enables rational beings to form universal concepts of things they haven’t experienced yet. For instance, once we have an concept of a horse and the concept of blackness we can consider the combination of these two concepts without having ever seen a black horse.
  2. Of course this is not the whole story, and common ends tend to be notoriously difficult to talk about (see, for instance, Marcus Berquist’s Common Good and Private Good). The particular qualification I want to add here is that while common ends can be shared without thereby being diminished it doesn’t follow that sharing always leaves it undiminished. For instance, orchestras are limited in their size because once they get too big they become unmanageable. The same goes for political communities and friendships and presumably any community. Furthermore, including bad musicians in an orchestra might also diminish the end insofar as those musicians get in the way of the orchestra performing well. But in these cases it is not the sharing per se that is diminishing the end, but rather the sharing with too many people or sharing with bad musicians. With private goods, no matter how you share you will always diminish your ends. Because this qualification doesn’t affect the overall thrust of my argument, I chose to just mention it here in the footnotes.



Why it’s called “motion”

I can’t believe it took me so long to realise this. Aristotelians sometimes (read: often) use the word “motion” to refer to change of any kind. Thus it is much broader than how we might use the word today. It’s certainly broader than mere change in location, but even we use it in a broader sense that.

But why? Why would you call change, in general, motion? Good question.

One of the questions Aristotle had to grapple with (and which we tend to ignore these days), is how change is possible and what it is. He realised that any instance of change is the actualisation of a potential. When a hot cup of coffee gets cold, for example, what is happening is that the cup’s potential for the being cold is actualised by the coldness in the surrounding air (say). When I pick the cup off the ground and place it on the desk, I am actualising the cup’s potential to be a meter above the ground (say).

So all change involves the actualisation of potentials. But does every actualisation of a potential involve change? No.

Go back to the cup sitting on the desk. Say it’s been sitting on the desk for a while now. Its location isn’t changing, but the desk continues to actualise its potential to be a meter above the ground. (If this potential weren’t being actualised, then the cup wouldn’t be a meter above the ground in the first place!) But this actualisation of the cup’s potential clearly isn’t an instance of change.

So there are some actualisations of potentials that are change, and some which aren’t. What separates the one case from the other? Surely it’s that change involves the movement from potential to actual. That is, it’s not merely that some potential is being actualised, but also that that potential wasn’t being actualised before. So, to use fancy genus-species language, the genus of change is the actualisation of a potential, and the specific difference is by movement from potential to actual.

As a side note, since efficient causation just is the actualisation of a potential this specific difference helps us distinguish between something like state causation versus something like event causation, as these terms are used in modern parlance. (I say “something like” because the Aristotelian thinks that (1) substances are the fundamental kinds of causes, not states/events, and (2) whereas typical construals of state/event causation involve one state/event causing another, Aristotelians typically understand cause and effect as two aspects of the same state/event.)

Whatever begins to exist has a cause

Consider the following argument:

  1. If it’s possible for a thing to come into existence without a cause, this possibility is grounded in a property of the thing itself, or a property of nothingness.
  2. This possibility is not grounded in a property of the thing itself, nor in a property of nothingness.
  3. Therefore, it is not possible for a thing to come into existence without a cause.

That possibilities are grounded in properties of things seems quite intuitive. In (1), we exclude the option of there being a property of an external thing that grounds this possibility, for it’s difficult to see how that would be a case of something coming into existence without a cause. (2) follows from the fact that only things that exist can exemplify properties. Nothingness, since it is the absence of all being, therefore doesn’t have any properties. Nor does the thing itself exemplify any properties prior to its existing.