Friday, June 18, 2021

Existential inertia and relativity

According to the doctrine of existential inertia, objects have a metaphysical tendency to continue existing absent interference. Existential inertia differs from ordinary physical inertia, in that existential inertia is supposed to come from the metaphysics of time and existence, while physical inertia comes from the laws of nature.

Let’s now imagine that Bob is a physical object that pops into existence at some point z0 in spacetime, in a universe with nothing that would annihilate Bob (and with Bob lacking any means of self-annihilation). Then according to existential inertia, Bob will continue to exist. But what does that mean in a relativistic setting? Times correspond to spacelike hypersurfaces. A time is future with respect to z0 provided that it corresponds to a spacelike hypersurface intersecting the future light-cone centered on z0. Thus, what we get is:

  1. If Bob exists at z0, then for every spacelike hypersurface H that intersects the future light-cone of z0, Bob exists at some location or other on H.

This is strange on two counts. First, it seems odd that for every spacelike hypersurface that intersects the future light-cone of z0, we have some sort of a metaphysical guarantee that Bob is somewhere on it—not at any particular place, mind you, but somewhere or other on it. Maybe it doesn’t seem as odd to you as it does to me, though.

Perhaps more seriously, however, (1) describes a metaphysical tendency that makes crucial reference to the speed of light.

In fact, (1) seems to somehow make speed-of-light limits have some sort of metaphysical force. For suppose that Bob faster-than-light travels from z0 to some point z1 outside the light-cone of z0. Then after that episode of faster-than-light travel, Bob could continue living a normal slower-than-light life, while violating (1) with respect to a number of hypersurfaces (that intersect the future cone of z0). Thus, while violations of existential inertia are supposed to come from destructive powers, a violation of (1) can come from simple faster-than-light travel.

If we suppose that the metaphysics of time requires a privileged reference frame, the above problems disappear. They also disappear if we think that objects come along with a privileged internal time sequence, and that existential inertia is defined with respect to that internal time sequence.

38 comments:

Wesley C. said...

From what I understand, physical inertia can be said to be a tendency or ability that physical objects have regarding motion - they continue to move in a specific direction, or have the ability and naturally exercised power to do so in some circumstances. If existential inertia is the same type of thing - an actual tendency intrinsic to the nature of things - then it wouldn't be an effect - then worries about incoherence might follow; how can a thing have a tendency to continue existing simpliciter?

Wesley C. said...

Er, it wouldn't be an effect of spacetime so much as something internal to the object itself.

Don said...

Ever since I realized what Wesley has pointed out, the term "existential inertia" has bugged me. All the principle of (physical) inertia says is that matter does nothing in and of itself. Inertia applies to resting objects too. As Wesley points out, its intrinsic to matter. Existential inertia is really a misnomer because it's defenders don't claim that existence is intrinsic to, or part of the essence of, the things they claim have existential inertia.

Walter Van den Acker said...

Simply call it existence. Of course existence is intrinsic to things. There are no things that don't exist.

Don said...

Walter, to have a thing intrinsically is to have it essentially. Things that exist essentially cannot not exist since it is of their essence to exist.

Walter Van den Acker said...

Don

Nothing 'has' existence. It is logically incoherent to talk about existing things and non-existing things, that's why 'existential inertia' is necessary.

Don said...

Do dinosaurs exist?

Dominik Kowalski said...


The denial of Meinongianism doesn't entail the intrinsic possession of existence

Dominik Kowalski said...
This comment has been removed by the author.
Dominik Kowalski said...

That's invalid on the face of it.

Of course, existence isn't a property, neither accidental nor essential and also not quidditative. The former leads to things possibly having being without existing, the latter implies that everything is necessary (and in necessary beings it causes brute facts). Existence is the *having* of properties. EI would require that at at every point after coming to be, the nature is prior to existence, which is absurd, for it is exactly the fact that the nature exists, that is in need of explanation. Thus existence could never be a part of the nature and it could neither be an isolated part of being that somehow is intrinsic to an individual, for its existence not being a part of its nature is the exact fact that accounts for its contingency and continued dependence on existence.

Unless your claim is merely that intrinsic here designates that it's a part of an individual without being a part of its nature. In that case it's trivially true.

When the existence of an individual is a real predicate (meaning in the broadest sense that sentences like "Socrates exists" designates something real) and we this accept the historically dominant thick theory, then EI is necessarily false and even a nonsensical concept, for the reality of existence prevents any nature to be more fundamental than it, be it in necessary or contingent beings.

On a thin theory we don't talk of existent individuals, so I don't know how much sense it makes to affirm it. It's then more of a continued state of instantiation of concepts. On the face of it this theory of existence is required for EI to work.

Or to put it easily, EI is an idea parasitic upon the notion of existence and not an idea standing on its own. There are a bunch of premises missing to get from your initial idea to the necessary truth of EI

IanS said...

Well, I don’t actually find (1) any odder than the idea that at any time after his creation, Bob is sure to be somewhere in space, not at any particular place, just somewhere or other. Put differently, I find existential inertia itself at least as puzzling as the details of how it applies. :-)

That aside, special relativity as usually taught starts with this basic claim: the split between space and time is frame dependent (with different frames related by the usual Lorentz transformations), and no frame is privileged. Surely this a metaphysical claim that crucially involves the speed of light? It’s there right from the get-go, even before introducing any dynamics.

Grant basic claim above. Then, as a matter of logic, for causality and existential inertia to be frame-independent, the motions of objects must be restricted to their previous forward light-cones. Your example illustrates this. The following takes it further.

Suppose that (in some reference fame) Bob is causally created at A = (x, t0). He remains at spatial position x until B = (x, t1). He then moves faster than light to C = (y, t2). He remains at y thereafter. In this story, A precedes B precedes C. But (because Bob moved faster than light), there will be a frame in which A precedes C precedes B. In that frame the story will go like this: Bob is created causally at A. Two extra copies of Bob are created acausally at C. The original Bob and one of his copies are destroyed acausally at B. The other copy remains. Things like this cannot be avoided if Bob travels faster than light.

But what exactly stops him? Answer: relativistic dynamics. To accelerate Bob (taken to be a massive, macroscopic object) through the speed of light would require infinite energy. Leaving that aside, the infinite force required would distort Bob so much that he would effectively lose his identity.

Short story: Relativistic spacetime by itself is not necessarily consistent with causality and existential inertia [as defined by (1)]. It is relativistic dynamics (i.e. the laws of motion) that enforces consistency. At least, that is what I’m suggesting…

Walter Van den Acker said...

Don

Do dinosaurs exist?

That depends on which theory of time you adhere to.
On presentism, dinosaurs do not exist. But that is not my point. My point is that dinosaurs are a collection (or an interaction) of existing things, so dinosaurs can stop existing in a way, but the fundamental 'things' they are composed of can't.
Fundamental things cannot come from nothing because ex nihilo nihil fit, and for the same reason they cannot become nothing either.

Don said...

Walter, I wasn't asking what a particular theory says to believe. I was asking what you believe. You made claims that I don't even understand ("Nothing 'has' existence. It is logically incoherent to talk about existing things and non-existing things"). So I was trying to understand your position. You've said that nothing has existence but also that fundamental things have existence. And it's unclear to me whether or not on your view anyone can even talk about the existence dinaosaurs.

It seems like Dominik is familiar with your position so I would suggest interacting with him because I'm not understanding it.

Dominik Kowalski said...

What are the "fundamental things" you're referring to? Do you want to go eliminativist on biological entities, saying that they're merely arrangements of fundamental particles? Or do you refer to the metaphysical principles like form and matter?

Either way though this once again depends on the notion of existence applied. To say that for a fundamental thing to exist is for its property concepts to be instantiated doesn't leave room for existential necessity. In fact that idea is absurd, for it would require self-instantiating concepts. Hence there's a tension between thin theory and PSR (recognized by Quineans like van Inwagen who maintain that *necessary* existence is a predicate).

This becomes even more apparent on a constituent ontology as championed by Grossmann and Armstrong, where material objects are thick particulars, made of and structured by the thin particulars making up its properties when instantiated within a bare particular. This once again prevents ascribing existential necessity.

Unless your claim is that there are no more fundamental physicals which could have destructive power against the objects you identify as fundamental. This then is merely a contingent truth about our world and doesn't designate a substantive metaphysical truth about those objects.

Dominik Kowalski said...

His claim is presumably based upon ideas like "if existence is a predicate, so must non-existence be" and attempted dilemmas like Plato's Beard

https://maverickphilosopher.typepad.com/maverick_philosopher/2021/03/platos-beard.html

Existence isn't a property, it adds nothing to a nature. It's the difference between something and nothing, but it tells us nothing about anything particular if we say "Something exists". This distinction between nature and existence isn't something exclusive to Thomists, it's rather widely recognized by philosophers like Kit Fine, van Inwagen and Donald Williams, who have no track with Thomism.

I think Walter adds physicalism to the debate, which kind of muddies the water, since physicalism as a thesis merely can tell us what exists and not what existence is. However it's the latter question the whole debate surrounding EI is dependent upon, since it's parasitic upon the answer. On a consistent physicalism talk of existing dinosaurs is a mere convention that one day gets replaced with the language of a more developed theory in physics.

I recommend Vallicellas article in the Neo-Aristotelian Perspective on Metaphysics "Existence: Two Dogmas of Analysis"

Don said...
This comment has been removed by the author.
Don said...

Walter, two final points: (1) If someone doesn't think things (chairs, persons, etc) exist then they don't need to explain the persisting existence of those things, which is what existential inertia (EI)--in is typical use--attempts to do. (2) I have never seen a defender of EI claim that existence is intrinsic to those things which they say exist by way of EI. So defenders of EI understand that concept in a much different way than you do. Dominik seems to understand your intention. I do not, which is a failure on my part since I'm just not familiar with it. From Dominik's posts I see that your position has its defenders. I'm just not familiar with it. But its uniqueness makes your use of the term EI dissimilar to the use of every defender of EI I have come across. Though, happily, to refer back to my initial post, your use of the term is not a misnomer.

Dominik Kowalski said...

No no no, none of the persons I mentioned defended a position such as his, this wasn't my intention. I pointed to philosophers who affirm the difference between essence and existence.

For EI to work I believe we have to dispense with existence altogether, like Russell did and affirm that sentences like "Socrates exists" are category errors. I think that on this ontology something akin to EI is possible, but not on ontologies that take sentences about singular existents seriously

Don said...

My mistake, Dominik. I have zero familiarity with the relevant literature.

Dominik Kowalski said...

No problem. Also because of its engagement with the best literature on the defenses of the thin theory, namely the work of C.J.F. Williams, I want to recommend Barry Miller's "Fullness of Being" as an awesome book on this topic. And of course Vallicella's article I already mentioned above

Wesley C. said...

@Dominik, In other words - saying that things have a tendency to continue existing once brought into being, or that it's in the nature of existence to continue sticking to things, or that existing things just naturally hang around and continue existing on their own without interference, doesn't make any sense on its face as this statement depends on a thick theory of existence?

Wesley C. said...

1) Now of course, even those who reject that existence is a property still accept that things have existence in some sense - that it belongs to them truly, and isn't something external to them. Couldn't one then say that things have a tendency to continue existing because existence is still properly attributed to things, and inertia can always be said of that which is truly attributed of things?

2) And what if we instead say that existence is an accident or property? Could EI get going on that way instead?

3) Also, is my objection that EI is incoherent because it requires that the form of a thing, or its nature, can reach out towards existence, which is circular?

Or that EI would require that a part of a thing's intelligible ratio included a reference to existence, and that such a reference to existence is incoherent?

Walter Van den Acker said...

Don

No, I did not say that nothing has existence but also that fundamental things have existence.
I said that nothing 'has' existence but that fundamental things exist.
There is, IMO and important difference between a thing 'having' existence, which implies that there are things that 'lack' it, so this gets you to the absurd position that there are things that exist and things that do not exist.
There are no things that don' exist, because that would mean there exist things that don't exist, which is obviously incoherent.
Dominik

By fundamental things I simply mean fundamental things. I am not speculating what exactly they are, just that they cannot possibly not exist and they cannot possibly stop existing.
So, I agree that existence is the difference between something and nothing. Hence, since ex nihilo nihil fit, things cannot come from nothing, but they also cannot become nothing.

Dominik Kowalski said...

Wait, you've conflated several positions into one here. To make it easier, let me say that in my view for something to exist is for its nature to be related to existence. Your, Wesley's existence, is the relation of your nature to existence. Wesley's existence designates something real though.

Your existence couldn't be conjoined to my nature, that doesn't make sense. More importantly, the existence each of us both possess is no quidditative property of ours. Our existence doesn't belong to us like our humanity does, it's not a property of our essence. It's that what relates our essence to existence.

Therefore it doesn't make sense to ask whether our existence sticks to our nature on its own. It does, but only in the trivial way I described above. But at no point does your existence become an independent entity of its own, a slice of existence so to speak. For the differentiation would require a nature of its own, however its exactly your nature (essence) that does the differentiation. Your existence isn't separable from your nature and I hope that I have roughly made clear why.

Now on the thick theory it's affirmed that existence is something real. And I have also argued as to how existence of individuals should be conceived of. Since existence is the most fundamental thing of all, a dependence relation of existing things to existence necessarily follows. Thus on this ontology, where we affirm existence as a real thing, the idea of EI can't even arise.

Dominik Kowalski said...

1) careful with your language. If you want to say that a nature has existence, you should be clear that e.g. priority of wholes or parts both presuppose existence. What I mean by that is that it needs to be appreciated that if we talk of existence, we speak of that which makes the difference between something and nothing. Everything else is to change the subject. Thus on pain of self-causation or assuming a nature before it could have existence, we must be careful as to what we mean when saying that something *has* existence.

This and the answer I gave above should make clear why, on pain of a vicious circle and false priority, the thing itself can't be said to exist inertially, for that requires that the nature could somehow contain its existence. But existence is presupposed by every nature.

2) That existence is accidental to things is my thesis, or rather the thesis of everyone who doesn't ascribe existential necessity to all individuals. It's of no help here. Note that accidental isn't meant to designate accidental property like hair color, but rather that it isn't necessarily linked to a nature.

Properties are accidental or essential. Accidental properties can be gained and lost without substantial change. With existence that would mean though that things could loose their existence while still existing, which is absurd. But it can't be an essential property either, for that would make the individual a necessary being. No essential properties can be lost without substantial change. You couldn't persist while ceasing to be human. But if you were essentially existent, you couldn't cease at all. Or come to be for that matter.

3) That's one way to formulate it. Basically every account that affirms the priority of a particular nature before its existence makes a basic mistake and isn't talking of existence anymore, but of instantiation or the like.

It's the same reason why Craigs statement that God's perfection entails his necessary existence is incoherent on the face of it. The missing appreciation for what existence is is also found in Descartes and subsequently criticized by Kant.

Admittedly I don't understand your last paragraph.

Dominik Kowalski said...

Hmmm. That's interesting. Of course we could ask how far that goes, but for that we require knowledge about how dependent objects are constituted and we don't have that knowledge. It also goes beyond this discussion. If that is all you wanted to express, I agree with that position.

Don said...

Walter, I agree that existence isn't had in the way that properties are had, and I even agree with the position that it is truly incorrect to say that it is had in any sense. If I ever suggested otherwise it was simply as a manner of speaking. The word "thing" can be used differently. If by thing one means "existing thing" then obviously it is absurd that there are things that don't exist but then we'd just use a different term to refer to non-existing essences (unicorns, dinosaurs, etc). If by thing one means "an essence" then it's not absurd to say that there are things that don't exist.

Wesley C. said...

@Dominik, If the individual existence of things is just their nature's relation to existence, then how can we ever even speak of things existing?

Their existence wouldn't even be something in them or had by them in any sense - not even as a principle or first perfection. The existence of things would just be a relation to something else - namely existence. And relations aren't solid or internal, but non-concrete abstract things. This would undermine the idea that things have existence or that we can coherently speak of concretely existing things.

Dominik Kowalski said...

Easy, because they're related to existence. This is what makes the nature actual. Before that the individual is at most an idea, like Sherlock Holmes. Unless related to existence and thus made concrete, talk of Holmes existing is false. It's the same of mythical creatures like Athena or Pegasus.

Relation might be the wrong term. The problem is that the existence is a unique act, not comparable, hence analogy is the only way to approach it. But if you don't like the terminology, what I have said is completely compatible with Pruss's preferred way of describing it, namely as the individual being caused (though here again we'd have to be careful with terminology, it's more of primary, rather than secondary causation). Another way of conceiving is has been made by Vallicella where existence is the unifier of an individuals constituents.

Though I personally still prefer the relation terminology. I take a roller coaster as a comparison. The vehicle is the nature, that gets connected to the rails (existence) via its wheels (individuals existence).

Don't get me wrong, existence belongs to individuals. But not to their nature. It's a belonging without being a property.

Wesley C. said...

@Dominik, Related to what exactly? If the existence of contingent things is just their relation to existence... then it makes to sense to say things exist. That implicitly attributes existence to them in some way. It gets even worse if we say the "existence" towards which things are related is God.

To say that things exist would then mean that things are related to existence, but that's a highly unintuitive way of speaking about existence - when we consider the individual existence of things, we don't think of it as a separate relation towards something else.

This is also evident in speaking of things as "losing" their existence if they were to be existentially annihilated - the language of losing something implies that existence belongs to them in some way (maybe something like a property, but a highly unusual category in the genus property???), and also implies their existence isn't a mere relation. Relations aren't attributed to things as belonging to them.

To speak of the concrete existence of things as just a relation seems to make their existence vague and mysteirous - out in the air, and not something concrete belonging to them. Similar problems would be with saying that the existence of things is just them being caused - that's also a highly extrinsic term, so similar problems would appear.

Is there a way of speaking of existence that isn't extrinsic, while also being classical or of the thick theory?

Wesley C. said...

*No sense to say things exist.

Don said...

Thanks!

Alexander R Pruss said...

Ian:

I take it there is no such thing as _just_ creating a particle. If one creates a particle, one creates a particle with a particular location, particular spin, etc. (Of course the relationship of the cause to these details may be indeterministic.) Similarly, then, if there were a metaphysical force that continues the existence of a thing, it surely wouldn't just continue its existence, but would continue it with a particular location, particular spin, etc.

Alexander R Pruss said...

Ian:

Maybe the issue is just that existential inertia treats objects as if the time-space split were frame-independent, but it's not?

Dominik Kowalski said...

I don't see a way to do so and frankly I don't see it as required. But I believe that perhaps there are misunderstandings here. In some sense existence is intrinsic, the individual is made up of its nature and its act of existence. What you demand would make it a property, but this is impossible. Even thinking that existence is on par with the rest of the nature leads to bruteness, for it wouldn't then be capable to give an account of how the other properties are distinguished from nothing. Considerations such as these show that necessarily there is an asymmetry here.

You almost had it when saying that the language implies some belonging. I only deny the stronger claim that would entail that even when everything external to the individual would be substracted, it would still exist. For then the asymmetry would be lost. It's a belonging without being a property

Wesley C. said...

@Dominik, Could we maybe say that the act of existence is what's primary in an individual thing, with the essence and other properties following from that? Or that the existence and essence are equally primary metaphysically, and it's the act of existence which is importantly connected to the essence that things truly possess, though not as property?

I agree with the rest of what you say, I'd only add that if existence isn't external to things but possessed by them in some sense, then if everything external would be removed they would still exist as their act of existence isn't external by definition.

swaggerswaggmann said...

If you place yourself in a relativistic setting then use magic "beyond the the speed of light" to try to argue something, the only thing you have successfully proved is that you don't understand relativity.

Malik said...

We all know the number one traffic rule of the universe – nothing can travel faster than the speed of light. And that happens to be 299,792.458 kilometres per second.
Hmm, Pruss must therefore be arguing that something is external to this traffic rule and outside of the universe therefore able to go beyond it.