# Potentiality, diversity, and limitation

Over on my post introducing potentiality from first principles, a reader raises some important questions that I thought would be worth answering in a separate post. If you haven’t read that post yet, I would encourage you to before continuing here.

This idea of “relative non-being” is the best explanation I have come across of the idea that potency “limits” act, though I still do not quite understand it. It seems to me that “relative non-being” really presupposes diversity in being rather than explaining that diversity; if so, it would be better just to take the diversity as primitive.

We could say that relative non-being is intrinsically differentiated, since whenever something is not X it is therefore something other than X.[1] Thus, another way of talking about relative non-being is in terms of otherness. This does not presuppose the diversity of being, however, because relative non-being is something outside of being—it influences being without making any positive contribution of being. Perhaps this would be clearer if we noted that by “being” we really mean non-relative being, and that likewise by “non-being” we really mean non-relative non-being. So, non-relative being is, non-relative non-being is not, and relative non-being is not X (for some X). We posit relative non-being in order to account for how it can be the case that more than one thing is. If there is only what is (being) and what is not (non-being), then nothing can diversify “isness” into this and that. On the other hand, if isness is composed with is-not-Xness then this opens up the possibility of isness also being composed with is-Xness (ie. is-not-Y for all Y other than X, more on this later). Since no one thing can be both X and not-X at the same time in the same sense, this gives us diversity of being.

What does it mean for being to compose with relative non-being? At this point, all we can say is that it involves mutual influence: being provides the positive contribution by virtue of which something is, whereas relative non-being provides the limits by virtue of which something is not X, or Y, or Z, etc. Neither exists in this influenced form prior to the composition, meaning that the relative non-being has no existence whatsoever apart from its composition with being, and being has no multiplication to this or that instance apart from its composition with relative non-being.

Maybe another way to put that would be: relative non-being can only account for multiplicity/diversity in being if there is diversity in relative non-being. But Parmenides could just reply that there can’t be diversity in relative non-being either: it couldn’t be differentiated by being (because that presupposes diversity in being, which relative non-being is supposed to account for); it couldn’t be differentiated by non-being (because that is nothing); and it couldn’t be differentiated by relative non-being (because any two things with relative non-being have that in common).

The first sentence here is spot on: relative non-being accounts for the diversity in being by virtue of the diversity that is present in relative non-being. But this diversity is not added to something that is otherwise one, but is an intrinsic feature of relative non-being. The relativity of relative non-being means that there is no such thing as relative non-being simpliciter, that is relative non-being without some qualification. This is because relative non-being is defined in terms of what it is relative to—the X in “is not X”—so that if we take this away then all we are left with is non-relative non-being, which is something else entirely.

Given this, Parmenides’s supposed reply doesn’t work: there can be diversity in relative non-being because there can be diversity in its qualifications. Suppose we have something that is not X, nor Y, nor anything else except Z, and we have something that is not X, nor Z, nor anything else except Y. Despite these both having relative non-being, they must be distinct from one another because the way in which they have relative non-being is different: each is qualified in a different way.

This is analogous to other determinables, such as location. You and I each have a location, but these locations themselves are distinct from one another.

At least as far as I understand Parmenides argument against multiplicity, he could give the same justification against multiplicity in relative non-being as against multiplicity in being – though I’m also not sure I understand Parmenides very well.

Parmenides’ argument seems to be:

(1) For there to be more than one being, they must be differentiated either by being or non-being.

(2) They can’t be differentiated by non-being, since that is nothing.

(3) They can’t be differentiated by being, since they have that in common.

Thus, there cannot be more than one being.

The Thomistic response seems to be to deny premise (1) and postulate relative non-being as a third option. But I don’t see why we cannot deny premise (3) instead and just say that yes, while they have “being” in common in the sense that they both exist, they also exist differently (e.g., by being of different kinds, or different individuals of the same kind). In other words, postulate diversity in being as a primitive principle. “Relative non-being” appears to me to be parasitic on this primitive diversity, and therefore superfluous as a response to Parmenides.

This reconstruction is somewhat accurate, but misses a crucial nuance. The problem in (3) is not simply that they have being in common (as they might have relative non-being, or locatedness in common), but that in both cases being is doing the same thing, namely grounding their isness. If all we can say about X is that it is and all that we can say about Y is that it is, then there is no distinction between them, because there is no sense in which Y is not X or vice versa.

I also don’t quite see how it follows that these two ways of conceiving of potentiality (relative non-being vs. capacity for actuality) are equivalent: in arguing that they are equivalent you describe both conceptions in two different ways and those different ways don’t seem equivalent to me.

Looking back, I certainly could have described the relevant moves in more detail. The basic idea is that we can show that the two accounts of potentiality are equivalent by starting from each one and showing how it can be understood in terms of the other.

Let’s start with relative non-being, which we have said limits being by excluding certain options within some domain. It cannot exclude everything in the domain, however, for then it would just be non-relative non-being. So, it must leave certain options “open.” Suppose we are considering a simple feature which can be one of three states, X, Y, or Z, and our relative non-being excludes X and Z. In this case, it leaves Y open. But remember that relative non-being makes no positive contribution of being itself. So, it grounds a certain openness to being without causing something to be or not—it limits what a thing is, but does not determine whether it is or not. But this is precisely what we said it means to be the passive capacity for act.

A similar series of moves can be applied in the opposite direction. Suppose we have some capacity for being Y. Then this capacity excludes being X and being Z, since when this capacity is realized then the thing is not X or Z. But this is just what relative non-being does.

In both cases, because the capacity is for a specific act and because the non-being is relative to a specific range of options, we can invert this range and get the other. We see that these two accounts are two sides of the same coin. While non-being excludes everything and being includes anything, relative non-being and the passive capacity for act restrict their scope, and therefore allow us to consider that scope in two ways—what is in or what is out. The passive capacity for act focuses on the former while relative non-being focuses on the latter, but in reality they are the same thing viewed from different perspectives.

[1] Throughout this post I refer to relative non-being in terms of being not-X. When not specified, the X should be understood to include one or many options within some domain. Considering colors, for instance, X could be a specific color or any collection thereof.

## 6 thoughts on “Potentiality, diversity, and limitation”

1. Thanks for this response. I think it addresses my hypothetical Parmenidean objection reasonably well. It hasn’t fully allayed my other concerns, though. You say:

“We could say that relative non-being is intrinsically differentiated, since whenever something is not X it is therefore something other than X. … This does not presuppose the diversity of being, however, because relative non-being is something outside of being—it influences being without making any positive contribution of being.”

I’m not so sure about that. Is relative non-being something outside of being that influences it – or is it (as it seems to me) merely a logical construction, the negation of “being X”, where the diverse ways of being are more fundamental than the diverse ways of non-being? I will grant that we can *postulate* relative non-being as a principle to explain the diversity of being – I think, at least, you have convinced me this isn’t entirely unreasonable – but I don’t think you have shown that this is preferable to just postulating diversity of being itself as primitive, or to some other theory.

You sort of addressed this in the previous post, where you said:

“What we don’t do is consider distinction to be theoretically primitive, in the sense that our theory simply assumes it without looking for its basis in reality. If we are faced with two theories, one of which is able to explain a phenomenon and the other of which simply refuses to explain it, the former is preferable when our entire aim is to give an account of reality.”

But it isn’t clear to me that relative non-being does provide an account for diversity of being in any deeper sense than postulating that diversity as primitive, nor is it clear that postulating diversity as primitive is “refusing to explain it”. In fact, I would say it does explain it: we can say that being is instrinsically differentiated, because nothing can simply *be* without *being something, specifically*.

“The problem in (3) is not simply that they have being in common (as they might have relative non-being, or locatedness in common), but that in both cases being is doing the same thing, namely grounding their isness.”

I still think we can deny (3), by saying that while the being is doing the same thing for X and Y in one sense (grounding their is-ness), it is at the same time doing different things for X and Y (grounding their is-X-ness and is-Y-ness, respectively) – again, because nothing can be without being something. And that means there is no need to deny (1) and postulate relative non-being as anything other than a logical construct, which by my lights is the more natural way of understanding the concept.

Regarding the equivalence of relative non-being with passive capacity for act: I guess I can sort of see how, if you consider “not being things other than X” as a kind of constitutive principle rather than a description, it turns into “being X” when conjoined with “absolute being” – if you think of being as fluid that conforms to the shape of whatever container you happen to put it in. In fact, I think Feser uses an analogy like that somewhere. But I think it is a slightly weird way of thinking about things, which becomes much more than weird when combined with the conception of God as Pure Act, and I don’t see anything forcing us to think of things that way.

• Thanks for the follow-up question. This is a really important point that I admit I have not spent as much time thinking about, so I appreciate you pushing me on it.

If I understand your concern correctly, it is that it seems unnecessary to posit something in addition to being and non-being in order to account for the diversity of being when we can just posit that being is intrinsically diversified itself. This would amount, as you say, to a rejection of (1) in your reconstructed Parmenidean argument, and it has the advantage of being a theoretically simpler theory. So, why the need for relative non-being to be outside of being like the Thomist requires? A few reasons come to mind.

First, it seems to me that such an alternative would commit us to a radical pluralism about being that would give even Heraclitus pause. After all, there would be no single notion of being common to all this insofar as they exist, since any such being would itself be individuated by its relevant qualification X. We might come to a concept of such a common being by abstracting the details from the individual beings, but this would not correspond to anything in reality anymore than the abstract notion of location does. In fact, it would be worse than that, because the idea of a common feature like location depends on a common predication of how this and that *is*, but on this proposal nothing *is*, but only is-X or is-Y, etc. There’s a difference between saying one thing *is-X* while another *is-Y*, compared to saying that *is* X while the other *is* Y. The latter depends on a common way of being that grounds isness while nevertheless allowing some kind of “shaping” of that isness to X or Y. The former way has no such common way of being, since any being has the X or Y “built into” it.

Second, this position would be subject to Merrick’s argument that we discussed in the first post. This would mean that the position could not even be coherently affirmed despite its initial coherence. The Thomist’s relative non-being proposal avoids the problem precisely because relative non-being is outside of being.

Third, it’s not clear to me how this view would make talk of unrealized being coherent, but which underlies things like change and non-existent possibles. Suppose that something is-X, then it would be impossible to be anything else since in order to do it would have to become is-Y. But these are two different beings, which means that the former thing went out of existence rather than simply modifying the way the existence is qualified (as the Thomist position allows). And if X is some non-existent possible, then it would a being-X that doesn’t exist, which is an incoherent idea on this position.

Fourth, it seems to me that this proposal does not have the necessary flexibility to account for the process of change. As I argued in an earlier post, potentials underlying change are non-stative potentials, which cover multiple incompatible states. This is fine on the Thomist position because there is nothing problematic with being potentially X and potentially Y at the same time (in terms of relative non-being, you can just understand this as excluding less than a stative relative non-being). But there is no way to something to be X and Y at the same time.

Those are the thoughts that come to mind. I just wanted to close by clarifying something. I’ve come to realize that there is an unfortunate ambiguity in the way we speak about being in these really fundamental metaphysical discussions. “Being” can be understood as a principle of things (in contrast to relative non-being), as well as a particular thing itself (as when we say there are two beings). That is, it can refer to the ground of existence in things or to the existents themselves. I raise this because we can happily affirm things like “whatever is is something” and “being is diversified within itself” when talking about existents (things). But we should bear in mind that when the Thomist is talking about things outside of being or composing with being, he is talking about the ground of existence (principles). You may well be aware of this distinction already, and I’m sorry if I’m stating the obvious, but in case it was needed I thought I should.

2. Those are good points, and they are helping me see the appeal of your position. Here are my thoughts in reply.

My concern isn’t only that it seems simpler or more natural to postulate intrinsic diversity to being as opposed to explaining this diversity via relative non-being, but also that it seems like diversity in relative non-being already presupposes diversity in being; i.e., relative non-being is differentiated by precisely by reference to various ways of being. Now, that isn’t anything like a decisive argument against it – one could reply that it is merely our concept of relative non-being which depends on our concept of diversity in being, but the true ontological dependency is the other way around. But it still seems to me to at least something of a difficulty in idea of relative non-being as fundamental.

Another difficulty I find with the view, which I haven’t articulated yet, is that I have no idea what it means for something to have some potentiality that isn’t actualized, if we equate relative potentiality with relative non-being. I can see what results when you combine “being” with “not being other than X”; namely, “being X”. But I have no idea what having the potentiality for X is supposed to mean or amount to when “potentiality for X” is supposed to be equivalent to “not being other than X” while the thing actually is other than X.

I can understand the potentiality for X if it is construed as a positive feature of the thing that has it – the potentiality itself is another way of being. This presupposes diversity in being, but still can serve to ground the reality of change (by featuring in an explanation for how new aspects of reality come to be).

Now, as for the reasons you present in favour of the relative non-being view:

First and second, I’m not sure that positing intrinsic diversity in being makes it so that those diverse ways of being have nothing in common, or that there is nothing in reality that could be called generic existence. To put it another way, I’ve never quite understood the force of arguments that “being is not a genus”. It seems to me that existence is indeterminate between, say, animality and non-animality in the same way that animality is indeterminate between rationality and non-rationality. So I don’t know why being could not be a genus, with the diverse ways of being as species. (In fact, in thinking about this proposal, it seems the various ways of being would end up being identified with the universals/forms that are instantiated as particular beings, i.e., substances or accidents.)

Third and fourth, on my view you would still have potentialities and causal powers; these would just themselves be positive features of reality that ground and explain possibility and change. E.g., in accidental change, you would have the substance (which stays the same throughout the change) with a potentiality for X, which together with the exercise of some causal power explains the coming to be of X. (The causal power is necessary because potentiality can’t actualize itself; the potentiality is necessary for the change to really occur in the substance.) A similar story can be told for substantial change, though telling it here would bring in more points of departure between my own (albeit not fully formed) views and the Thomistic position. For a non-existent possible being X, I think we should (or at least could) say it is something that *would be X if it existed*, not something that *is X* even though it doesn’t exist. (Maybe that last point could be clarified by saying that I don’t think we should take the existential quantifier in modal logic to be ontologically committing; you need an existence predicate to do that work.)

Finally, nothing wrong with occasionally stating the obvious in this discussion! What is obvious from one perspective may not always be so from others; never hurts to try to bring more clarity. 🙂

• Apologies for the delayed response. Unfortunately, to respond to some of your concerns would be better suited to another post or two, which I may get to in the future as I continue my journey through potentiality. For the time being, let me give some brief responses to just some of the things you raise.

> … it seems like diversity in relative non-being already presupposes diversity in being; i.e., relative non-being is differentiated by precisely by reference to various ways of being.

There are ambiguities in this that make it a bit hard to evaluate. Perhaps the best place to start is the tease out the difference between diversity of being and ways of being. Relative non-being certainly is differentiated by reference to various ways of being. When something is X, the being is the isness and the way of being is the Xness. These ways of being that are referenced by the relative non-being are not themselves being, but represent the range of ways in which being may be limited or qualified. Suppose we consider location again: to be not-there does not require that some being be there, only that the limitation I take on is within some range that includes here and there, and that within this range here is not there. These ways of being are part of how relative non-being works to ground the *extrinsic* diversity of being (extrinsic because it comes from outside of being), whereas what we’re contrasting this view with is the intrinsic diversity of being. So, in the sense that both parts of this sentence describe the same thing it unproblematic, but this is not the relevant sense.

> Another difficulty I find with the view, which I haven’t articulated yet, is that I have no idea what it means for something to have some potentiality that isn’t actualized, if we equate relative potentiality with relative non-being.

A first, but minor, point is that potentiality as such is relative non-being (or perhaps, the principle of relative non-being). There is no distinction between relative and non-relative potentiality here. Second, and more importantly, this is a perfectly reasonable question, since I haven’t actually articulated this yet (it will come in a future post, when I also discuss matter). Let us suppose that something has the potential for X and the potential for Y, where X and Y are alternatives to one another within some common domain (like two colors, or two locations, or something). Relative non-being is getting at how these potentials are different from one another in relation to their actualization, not at how they can both obtain simultaneously (this is the job of matter). The key thing here is that when the thing is X, it is *not* Y because the potential for X is also the potential for *not-Y* (and vice versa: the potential for Y is the potential for not-X). The relative non-being here is helping us understand how there could be these alternative ways of being within this domain, by giving us the very notion of “alternatives” in the first place. The non-actualization of Y is grounded in: (1) the actualization of X, (2) X’s being not-Y, and (3) the underlying thing which grounds both X and Y together. Relative non-being only helps us with (2).

> First and second, I’m not sure that positing intrinsic diversity in being makes it so that those diverse ways of being have nothing in common, or that there is nothing in reality that could be called generic existence.

I could be wrong, but I think the basic idea relevant to us is this (this does not quite get to the conclusion that being is not a genus, but it is sufficient for our purposes). If being-X and being-Y really have something in common, which grounds a common (or generic) affirmation of “is”, then this will be being as such. But this being could not be intrinsically X or intrinsically Y, since X is not Y and Y is not X. X and Y must therefore be something other than being, etc. etc. Thus, if we wish to deny this general scheme, we need to reject that there is anything really in common between all these intrinsically diverse being-*s. We might *conceptually* group each of these, and label this group “generic being”, but this would not correspond with anything in reality.

> Third and fourth, on my view you would still have potentialities and causal powers; these would just themselves be positive features of reality that ground and explain possibility and change…

It may surprise you to hear that I agree with almost everything in this paragraph. I explained at the end of my first post how I think potentialities can be affirmed as positive features of reality through their relations to act. But I think the main reason there can be so much agreement is that nothing here really offers an alternative account of what potentialities are, it mostly just repeats how they’re meant to work in the broader Aristotelian system. That said, it’s not clear to me what you mean by potentiality and causal power on your account, since potentialities need to work in a fundamentally different way from actualities. For instance, it’s impossible to be here and there at the same time, but there is nothing impossible about being potentially here and potentially there are the same time. I suppose you could say that the difference lies in the content of X of being-X. But this doesn’t really amount to an alternative account as much as a refusal to give an account. In fact, this sounds a lot like we’re using the term “being” in the sense of things rather than principles.

Perhaps another way to put this worry is as follows. If is-Y and is-potentially-Y are positive features of reality in the same way, then to talk of the former being the actualization of the latter is as meaningful as saying that redness is the actualization of greenness. If they are not positive features of reality in the same way, or in the way that I cash them out, then how are they related? We don’t need to get too into it (in talking about fundamental metaphysics we’ll need to stop somewhere), but it would be good to know what it is that distinguishes these two “classes” of being. My guess is that in answering this we would come up with something which is for all intents and purposes the same as one of the two accounts I’ve given.

• > These ways of being that are referenced by the relative non-being are not themselves being, but represent the range of ways in which being may be limited or qualified.

As I said before, your explaination of how potentiality “limits” act is the clearest I’ve found… but it is still a strange way of thinking, to me. You seem to start from the view that being is in some way the fullest possible concept, including all possible quiddities, and relative non-being has to come along and excise various alternatives to bring being down to being-X. To me it is more natural to see being as the emptiest possible concept, including no quiddity at all, only the mere fact of existence.

Now, precisely because being is the emptiest possible concept, it has the greatest extension (i.e., as a predicate, it applies to all existing things). But a further qualification X can be “outside being” in the sense that it specifies some quiddity which is no part of the concept of being, while at the same time be “included in being” in the sense that everything which is X has being.

I think we can gain some clarity by keeping in mind these two different ways in which something may be “inside” or “outside” of being. I recently came across a paper that follows this line of thinking; I would be curious to know your thoughts on it:

Click to access aporiageneris.pdf

(In case the link doesn’t come through, the paper is ‘Conceptual Atomism, “Aporia Generis” and a Way Out for Leibniz and the Aristotelians’ by Lukas Novak.)

> A first, but minor, point is that potentiality as such is relative non-being (or perhaps, the principle of relative non-being). There is no distinction between relative and non-relative potentiality here.

Yep, that was just a typo on my part.

> Second, and more importantly, this is a perfectly reasonable question, since I haven’t actually articulated this yet (it will come in a future post, when I also discuss matter).

Looking forward to reading that future post. 🙂 (Just in case that gives you motivation to write it sooner, haha. But no pressure! I’m sure you are busy.)

> If being-X and being-Y really have something in common, which grounds a common (or generic) affirmation of “is”, then this will be being as such. But this being could not be intrinsically X or intrinsically Y, since X is not Y and Y is not X. X and Y must therefore be something other than being, etc. etc. Thus, if we wish to deny this general scheme, we need to reject that there is anything really in common between all these intrinsically diverse being-*s. We might *conceptually* group each of these, and label this group “generic being”, but this would not correspond with anything in reality.

So… I don’t see how this follows. Agreed, being-as-such can’t be intrinsically X or intrinsically Y. And X is intrinsically X, so can’t be being-as-such, so it is something other than being in that sense. But that doesn’t mean X isn’t a form of being or inside being in another sense. “Vertebrate animality” and “invertebrate animality” really do have “animality” in common even though animality isn’t intrinsically either vertebrate or invertebrate. Yet you can’t have an animal that is neither vertebrate nor invertebrate; an animal is always an animal of some kind. There being many different ways of being, which nonetheless have being-as-such in common, seems perfectly analogous with there being many different species of animal, which nonetheless have animality in common.

Maybe we are entering territory where the differences are merely verbal; it is possible that I could be thinking of different quiddities like X or Y as ways of being construed positively; while you are thinking of relative non-being in basically the same way construed negatively. I’m not sure.

> If is-Y and is-potentially-Y are positive features of reality in the same way, then to talk of the former being the actualization of the latter is as meaningful as saying that redness is the actualization of greenness. If they are not positive features of reality in the same way, or in the way that I cash them out, then how are they related?

That is a very good question and one I would like to figure out the answer to. My initial inclination is just to say that there is a richer structure to the ways of being than merely whether or not they are ways of being. Potentiality-for-redness is oriented towards redness in a way that greenness is not. I think this could end up being basically the same as your “passive capacity for act” account, but remain unconvinced that it would thus be equivalent to the notion of relative non-being.

Thanks again for the discussion!

• Sorry, again, for the late reply. I have been thinking about your most recent response since you sent it, but I haven’t had a chance to write down some thoughts.

I think this way of characterizing my view in contrast to yours is helpful. It certainly helps me better understand the difference, as well as the relevance of the question of whether being is a genus. I have not had a chance to read the article you linked, but I can perhaps clarify the reason Thomists deny being is a genus.

I think the basic idea from the Thomistic perspective is the following. If G is a real genus of X and Y, then (1) G must be that which X and Y have in common and (2) at least one of X and Y must have something additional to G, which serves as the specific difference D. If there were no difference, then X and Y would agree entirely with G and therefore each other, collapsing everything into one. And the difference needs to be additional to (or wholly extrinsic to, or outside of) G in the sense that it cannot be a species of G in any way, since it is part of the definition of (and therefore prior to) the species. To put this another (and perhaps clearer) way, it means that G must be excluded from the definition of the D. But, if we exclude being from anything, then it is nothing, so that if being us a genus then any specific difference must be nothing. And if there is no specific difference, then everything collapses into one, and being is not really a genus of anything after all.

Here is an extended quote from Oderberg talking about this question, which may help add some nuance to what I’ve said:

> There are, however, serious difficulties with the idea that being is a genus. First is how we are then to break up being in order to form the first division in the [Porphyrian] tree. The standard, and most plausible, first division is into substance and accident — everything is either one or the other. If this is right we need to find the specific differences of being that constitute substance as substance and accident as accident. What could these be? The obvious answer is that substantiality itself and accidence itself are the differentiate of being. But substantiality and accidence are themselves being — universals instantiated by all substances and all accidents, respectively — and so we would have being differentiated by being. Yet this cannot work, because the specific difference of something has to be wholly *extrinsic* to what it differentiates. So, for example, the specific difference of gold is to have some atomic number 79. This difference is wholly extrinsic to gold’s genus *metal*, since being metal is no part of what it is to have atomic number 79. Having atomic number 79 may *entail* being a metal, but the difference itself is in no way explained or understood in terms of being a metal: it is explained and understood solely in terms of an atom’s have 79 protons in its nucleus.
>
> By contrast, being a substance does not merely entail having being, but it is part of what it *is* to be a substance that substances have being… So what could differentiate being? The only thing, as it were, that is wholly extrinsic to being is — nothing. Yet it is impossible for nothing to be a differential: differentiate are always something or other, some element of reality that determines the specific identity of a thing. This is one reason being cannot be a genus.
>
> The second concerns whether ‘being’ is univocal, equivocal, or analogous. If it were univocal it would be like terms such as ‘human’, ‘dolphin’, ‘water’, ‘oak tree’, and so on. All of the things that respectively fall under these terms do so in the same way, for the same reason — they share the essence expressed by each term. Being does not work this way. When we abstract *humanity* from individual humans, or *oak tree* from individual oaks, we abstract away the accidents and are left with the essence. We cannot do this with being, since it is heterogeneous: there is substantial being, contingent being, possible being, absolute being, relative being, intrinsic being, extrinsic being, and so on. These features of being are not accidents from which we can abstract to form a clear, complete, and homogeneous concept of being. For each and every kind of being, the way in which being manifests itself is essential to that kind (contingent beings are essentially contingent, accidental beings are essentially accidental, and so on). To try to abstract away from these essential features in order to arrive at a concept of being *as such* is a metaphysical and conceptual mistake, since it is to abstract from what is essential to the kinds of being.
>
> It might be objected that we do not abstract only from accidents, because we also abstract from specific differences: we can abstract *rationality* and consider man only as *animal*, investigating what humans have in common with other animals that are not rational. But, as I argued earlier, the kinds of being are not specific differences. We I try to abstract fro , say, substantiality, I abstract from the entire essence of the thing that is a substance, *its being included*. What I am left with is not being as such, but nothing. Hence ‘being’ is not a univocal term. (David Oderberg, Real Essentialism, 107–8)