Saturday, January 23, 2021

Realities ≤ Universes ≤ Worlds ≤ Cosmos

My new book project, The Weirdness of the World, engages big-picture metaphysics and cosmology. This has me thinking about solipsism and materialism (aka physicalism), among other things. According to solipsism, the only thing that exists is my own mind. According to materialism, the only things that exist are material things. These claims are ambiguous in scope. The only things that exist where?

Consider ordinary cases of implicitly restricted quantifiers. If I say, "there's no beer!" what I mean, presumbly, is that there's no beer in the fridge or that there's no beer in the house, not that there's no beer anywhere in the universe. What I'm saying, in quantificational logic, is that it is not the case that there exists an X such that X is a beer and (implicitly) X is in my fridge.

Now try solipsism. According to solipsism, "there's nothing but my own mind!" But this could mean any of a few different things. Presumably it's not restricted just to my house, since then solipsism (well, a cousin of it) would be true whenever I'm home alone. But it could be restricted just to my universe. According to solipsism, in this sense, my mind is the only thing that exists in the universe. But this leaves open the possibility that, if there are other universes, they might be full of things other than me. Call this universal solipsism. A stronger, bolder, more radical solipsism might commit to the view that no matter how many universes there are, not one of them contains anything apart from my own mind. We could call this still-lonelier view cosmic solipsism.

Parallel considerations apply to materialism. Universal materialism holds that everything that exists in this universe is material. Cosmic materialism holds that everything that exists in any universe, including other universes if there are any, is material.

Metaphysical idealism, denial of the existence of ghosts or gods, denial of emergent properties, supervenience views, reductionist views (i.e., X is "nothing but" Y), etc., all admit the same ambiguity. The general structure can be expressed as "It is not the case that there exists an X such that X is F and (implicitly) X is G, where G specifies some grand scope like "in this universe" or "anywhere in the entire cosmos".

There are lots of potential scope specifications grand enough to fit the grand ambitions of negative metaphysical and cosmological claims, such as "in any metaphysically possible world" or "in any region of the cosmos in which the same laws of nature obtain" or "in any region spatiotemporally continuous with ours" or "in any bubble universe arising from the same inflationary foam"....

However, there are four scope specifications that I'm finding useful in my own thinking, which I will semi-stipulatively call, in increasing scope, realities, universes, worlds, and the cosmos.

Let's start with universes. As far as I'm aware, there isn't one orthodox usage of "universe" across philosophy and physics -- a variety of precisifications of this idea will be useful for different purposes. One aspect of usage that I'd like to respect is that multiverse theories postulate the existence of multiple universes, entirely or almost entirely spatiotemporally or causally disconnected from each other and possibly instantiating different laws of nature or having different physical constants. So far, I haven't found a definition that makes this precise without running into troubles. I'm going to embrace one definition, note three concerns, then put a big asterisk on those concerns.

That said, a universe, in my intended sense, is a maximal spatiotemporally connected region and its contents, or similar. Everything spatiotemporally connected to us -- no matter how remote in time or space, possibly far beyond the edge of the "observable universe" -- is part of our universe in this sense.

Concern 1: What about universes that aren't spatiotemporal? I don't want to rule those out by definition. Maybe space and time are features of some universes but not others.

Concern 2: What about partial connection? Maybe one universe nucleates from another, out the backside of a black hole for example, with just the tiniest bit of spatiotemporal connectivity -- two giant lobes, perhaps, which share a tiny part in their past but otherwise remain unconnnected. Another tricky case might be a version of the "many worlds" view of quantum mechanics in which "worlds" (universes?) share a spatiotemporal past but become (mostly?) disconnected going forward after a splitting event.

Concern 3: If spatiality or spatiotemporality is a derivative or functional concept, this definition might wreak havoc with the distinction between universes and realities I will describe below.

I henceforth disregard all three concerns, hoping that the promissory "or similar" can address #1, that issue #2 can be left as a terminological decision with an admittedly vague boundary, and that the clarification of "realities" below can partly address #3.

Next: the cosmos. I reserve this term for the largest category of what exists. By definition, there cannot be more than one cosmos. It is everything in the strictest sense of everything.

Next: worlds. This word has highly variable usage. I've already mentioned the "many worlds" interpretation of quantum mechanics. In another sense, a planet can be a "world", or even just a society ("the world of ancient China"). In another sense, a "world" can be larger than a universe. That is my intended sense. Modal realism is the view that "possible worlds" really exist. A modal realist could, I think (contra David Lewis), hold that the actual world contains multiple spatiotemporally unconnected universes and that other possible worlds have either one or many spatiotemporally unconnected universes. Maybe, for example, in our world, muliple universes arise from inflationary foam, but also another world exists without the kind of laws or initial conditions that give rise to inflation. Maybe not, of course! But so as not to rule out the possibility by definition, it's useful to have a (possibly redundant) category between universes and the cosmos: There might be more than one world, and it might be the case that at least one of those worlds might contain more than one universe. Thus universes ≤ worlds ≤ cosmos.

Finally, realities. The intuitive notion here is that of a "virtual reality" or (not the same, but sharing some features) a simulation in Nick Bostrom's and David Chalmers's sense. Imagine someone living in The Matrix. Their biological body is stored motionless in a warehouse somewhere, but they experience a wide reality in which they do all sorts of things, coordinated with other people who experience the same reality -- like you're all in a big shared VR game. Underneath, the whole thing is managed by megacomputers. People in such a reality would be in the same physical universe as the computers who manage the reality. But their experiential reality would be quite different. The universe might contain many virtual realities, populated with entities who experience space and time very differently from how it runs outside of their realities. And some of these realities might be such that no matter how far you travel within them, or what you do, you can make no further independent contact with the universe beyond. The inhabitants are, so to speak, entirely enclosed within.

Thus, a universe could contain many virtual realities, or other enclosed pockets in which the experienced spatiotemporal manifold of the entities within it doesn't map well onto the spatiotemporal structure of the larger universe that contains them. (Depending on your metaphysics of space and time, this could raise concern #3 about the definition of "universe" above.)

Okay, so here is the most boring possible view: reality = universe = world = cosmos. There are no virtual realities or other pocket realities of the sort just described. There is only one universe. And that universe is the whole of the cosmos. This might be true. (Yawn.)

Here is the wildest possible view: reality < universe < world < cosmos. There are multiple realities in our universe (perhaps we ourselves are inside a simulation, instead of being at the "ground level" of our universe), multiple universes in our world, and muliple worlds in the cosmos.

Back to materialism, disambiguated with all the inequalities in place:

We might live in a reality that is wholly material (in the somewhat attenuated sense that what is empirically available to us is experienced as matter occurring in space and time and nothing more), while our universe is not material. (If this seems incoherent or inconceivable, check out my essay Kant Meets Cyberpunk.) Our universe might be wholly material, while our world contains other universes that are not. Our world might contain only material universes, but other worlds might contain universes that aren't wholly material. Or everything that exists in the every world in the cosmos might be wholly material. These are at least four different strengths of the materialist thesis. In fact, there are more strengths, given that is this only a rough pass at scope specification.

The reality-universe distinction will be tricky for solipsism, but apart from that it will look like the materialism case, if we're okay with the "or similar" clause on the definition of universes.

Now do it for ghosts and gods if you like. See? Kind of interesting, I hope -- at least if you're the kind of philosophy/cosmology nerd who would read to the end of a post like this!



Skepticism, Godzilla, and the Artificial Computerized Many-Branching You (Nov 15, 2013)

Duplicating the Universe (Apr 29, 2015)

Your Infinite Counterparts (May 1, 2020)

[image source]


  1. An interesting exploration Eric!

    I'm not quite following what you're trying to do with "world" here. Do you mean a particular conception of multiverse? Such as inflationary bubble universes as opposed to the quantum multiverse, or black hole universes? (BTW, are you familiar with Max Tegmark's levels of multiverse?)

    At some point this starts to feel like nested namespaces, a concept from programming you might be familiar with.

    On concern 2, one thing that might also complicate things is there is ever found a way to detect the other universes, since it would imply a causal interactions between them. For example, some cosmologists are looking for signs of a collision with another bubble universe in the CMB. And different worlds in the many-worlds interpretation, in theory, still interfere with each other, but detecting that interference is extraordinarily difficult.

    Concern 3 is interesting since some physicists think space might emerge from quantum entanglement, and time from entropy. Our spacetime reality might be a sort of natural virtual reality, or emergent reality if we prefer that terminology.

    Anyway, I like the sound of this book. Looking forward to it!

  2. Your sense of "cosmos" presumes that unrestricted quantification is possible, allowing us to talk about "everything in the strictest sense of everything." One might be dubious that there is any such thing. Quantification always occurs in a linguistic context, but maybe there isn't a univocal context in which 'everything' operates that way.

  3. SelfAware: On nesting: Yes, they nest, or at least that's my intention. I'm not sure that "world" has cosmological/metaphysical oomph that is strictly intermediate between "universe" and "cosmos", although one start might be to consider whether there's a principle by which universes could be grouped into sets sometimes larger than one that have some kind of in-the-same-region relation, with a non-arbitrary boundary to that region that is short of the entire cosmos. On concern 2: Yes, that's exactly the kind of worry I had in mind. There's still some intuitive sense (perhaps with gray boundaries) in which they still seem to be different universes or "worlds", which the terminology aims to respect. On 3: Yes, and that relates to concern 1 also. Furthermore, depending on what counts as sufficient for the emergence, virtual realities might end up counting as "universes" in a potentially confusing way (and/or a potentially correct way). The complexity of these issues is probably why it's hard to come up with a good, relatively theory-neutral way of defining what a "universe" is.

    PD: Granted, that's an issue. Tricky cases abound, such as numbers, possible entities, fictional entities, and absences. There might not be a uniquely maximal specification of "everything" such that it makes sense to say that it includes all and only entities that exist.

  4. Here’s how I try to make sense of things professor, and I believe this avoids the three concerns you’ve mentioned:

    I begin with epistemic solipsism. I can prove to myself that I exist, though I also realize that that’s the only worldly truth which I can ever be perfect assured of. You should be able to do the same (that is if you also know that you exist). But I also presume that I’m not all that exists since why would I be so special? I may be all that I can prove exists, but it makes no sense to me that I’d be all that exists.

    Then secondly there’s my single principle of metaphysics. Here I observe that wherever causality itself fails, nothing will exist to potentially grasp. But for a person like myself who’d like to understand, it makes no sense to theorize various supernatural answers since they’d lack a causal chain to potentially grasp. So instead I presume perfect causality. Note that at least I’d fail as a naturalist trying to grasp the ungraspable.

    Observe that from this position however, I can only be part of a single massively interconnected reality (or universe, or world), and that this place will be defined by perfectly determined causal dynamics (that is given my natural presumption above). I can understand why various modern physicists would use our inability to grasp quantum mechanics to postulate solutions such as “many worlds”, though I consider that essentially unfalsifiable speculation. In any case if causality were to create virtually infinite “universes” (and presumably they’d spawn their own as well!), then they’d all ultimately just be part of a single causal system that couldn’t possibly deviate even slightly. (And clearly any “virtual worlds” from the premise of naturalism will also not escape, and regardless of what’s felt under the domain of such a computer.)

    The one exception that I do make for extra realities (or universes, or worlds), involves a variety which never has and never will have any causal connection with ours whatsoever. Each would still involve noumenal reality itself, though one such realm wouldn’t effectively exist to another such realm. So yes, these could be called different worlds under a single cosmos under this system.

    This is part of my plan to help support science through the creation of a community of respected professionals armed with various generally accepted principles of metaphysics, epistemology, and axiology. Given that I’d love for you to help found such a community, I hope this helps with your coming book!

  5. This post is interesting, but I am not sure I completely understand what your schema is trying to capture. For example, consider the following question:

    > Is materialism a thesis about the uni- or multi-verse at the actual world or about all worlds?

    That kind of question appears to be what is driving you. However, it appears to be handled by, e.g., the most straightforward quantified modal logic, where the domain of what exists is fixed (or the same for each world).

    It might be worth developing what I am trying to get at here. The following might be a useful alternative (inspired by Ed Zalta's work) worth considering, given your purposes. Let's take materialist theses and their alternatives to, at least, tell us about the designation of '_F_' below. Let's also assume that '_F_' does not designate the property _abstract_. Finally, let's assume that to exemplify abstractness is just to exemplify the property of _being a v such that it is not possible that v is F_.

    1. The cosmos contains all and only worlds.
    2. An abstract individual _w_ is a world just in case, possibly, all and only propositions true at _w_ are, in fact, true. (think Wittgenstein or maybe Kripke rather than Lewis)
    3. An individual _x_ is a uni- or multi-verse at _w_ just in case
    a. _x_ is _F_ at _w_,
    b. every object _u_ that is F at _w_ is part of _x_, and
    c. _x_ exemplifies exactly the propositional properties _being a v such that p_, where _p_ is true at _w_.

    For now, I'll be silent on 'realities' (but worlds have proper parts or situations that are not worlds, and that might be helpful to think about). For the schema above, I think Concern 1 becomes a worry about _F_. That might have something to do with material, physical, concrete, spatial, temporal, or causal relations. Or it might have to do with some other relation entirely. I should also note that clause 3.b needs to have 'is part of' cashed out in a manner appropriate for objects that are at least possibly _F_. I don't see Concerns 2 and 3 arising in the above scheme. I think the 'quantifier issue' you allude to is handled quite intuitively in the above.

  6. 'engages big-picture metaphysics and cosmology'...

    It's not one's scope is reduced by experience but by description...

    Tension may be the motion of three and more forces...
    ...+ - =...positive negative equal...

    Right now it's thanks again...

  7. So would Wittgenstein need to rephrase the first sentence of the Tractatus?

  8. Thanks for the continuing comments, folks!

    Phil Eric: Do you end up being committed to determinism a priori? I guess I'm less inclined to reason from first principles like that, instead favoring a more coherentist or Neurath's boat approach, in which anything and everything is up for grabs, depending on how the whole seems to be fitting together.

    Wes: Thanks, that's very helpful and not far from how I was thinking about worlds. Universes is trickier, I think. Although concerns 2 and 3 might not arise for worlds specified as you described, I'm inclined to think they do still tend to arise for universes on the most obvious possible specifications of F. It will be tricky to specify F just right while respecting the universe/multiverse distinction, yes?

    Howie: Maybe so!

  9. Eric: I think you are thinking of worlds in a non-Wittgensteinian or Lewisian way. I don't think Wittgenstein should have revised the Tractatus. I think Lewis's concrete possibilia are incoherent, but Wittgenstein's (and there are glimmers of this in Kripke) way of thinking of worlds is a superior regimentation of our language.

    Also, I am not sure I understand the final question directed toward me. I don't see how a universal or multiversal thesis (like materialism) can fall prey to disrespecting the universe/multiverse distinction. At some worlds, you might have a universe. At others, you might have a multiverse. Or you might have only universes or only multiverses. I'd guess physics gives us some idea of what kind of -verses we may or may not include in our domain in the first place. Certainly, it gives us some clue of what kind of -verse is at the (unique) actual world.

    Maybe I don't get concerns 2 and 3 (and maybe I don't even understand, or failed to map concern 1 onto my scheme correctly). Finally, I'd like to revise my initial post; 'cosmos' is probably not needed or, at best, distracting. And, again, I'll leave 'reality' for another time (although I think there is a lot of interesting stuff to say there).

  10. Ah, no professor, the determinism that I speak of is not a priori at all. It’s a potentially useful (and possibly false) presumption rather than anything linguistically or mathematically true. The purpose of my single principle of metaphysics is to foster a more effective a posteriori environment, namely the institution of science.

    Observe that whenever someone decides that they’ve figured something out, this will be because they perceive a causal chain which gives them a feeling of understanding. But what would happen if such a causal chain were missing ontologically? Here a person might imagine that he/she sees a causal chain to thus grasp, though as we’ve established they’ll be wrong since in this case one will not exist. This is to say that magic is not possible to understand by means of worldly dynamics.

    If my single principle of metaphysics were to become widely adopted then each new scientist would have a choice to make. He/she could either presume that all things ultimately function by means of absolute causal dynamics, or presume that causality can ontologically fail and so open the door to magic. But the eternal question for this second variety of scientist would be, why try to understand that which is presumed to have no worldly explanation?

    Though today science is populated by both strong and weak naturalists, from this brand of metaphysics the two sides would be segregated (and I suppose in effect one form of scientist would tend t be demoted to the other from time to time). From the strong naturalist side there would be a single world (perhaps with machines in it that provide immersive sensual realities, and perhaps black holes and whatnot which causally create strange places that we can’t otherwise get to), though there might also be full extra worlds that we can’t know about since they have absolutely no causal connection with ours. The most causally dubious proposals however would be left for the second variety of scientist to explore.

    I suppose this proposal might be a bit boring for a book entitled “The Weirdness of the World”. If you went my way a better title might be “The Weirdness of Science”, and from the perspective that it’s philosophy’s job to come up with effective principles from which to better instruct science so that the world’s weirdness might be made more plain to us.

  11. Having read further I found, "Wittgenstein, however, does not think that the confusion of kinds of dots was the deepest mistake he made in the Tractatus" And "(x is in this room)"...
    ..., "Wittgenstein’s Logical Atomism, First published Mon Nov 22, 2004; substantive revision Thu Dec 14, 2017"...

    Before I forgot to add x to +-=...that neutral-x pushes "all is in motion"... where we have +-=x in any order, and representing oneself also in the mix...

    Thanks for helping me understand more the stability of movement...

  12. Thanks for the continuing comments, folks!

    Phil Eric: I have a broader starting point, I think. For example, I disagree that "whenever someone decides that they’ve figured something out, this will be because they perceive a causal chain which gives them a feeling of understanding". One possible example seems to be mathematical understanding, since mathematical relationships are not ordinarily thought of as causal. (On some views, they might be, but my sense is that's a minority view.)

    Wes: Right, it's neither Lewis nor Wittgenstein. It's not Lewis, in part, because (as I recall, but point me somewhere if I'm mistaken), he defines worlds in terms of spatiotemporal relations. Therefore, two spatiotemporally disconnected universes could not be part of the same "world" by definition. Thus, it will align poorly with some versions of multiverse theory. This is one way in which the multiverse/universe/world distinction can start to get tricky.

  13. I suggested that what you consider as "tricky" arises because you think of worlds as possibly concrete (or, worse, concrete possibilia or as involving spatiotemporal relations like Lewis). I suggested not to think of worlds this way. If you think of worlds as impossibly concrete (or impossibly F, where maybe F = concrete), the worries do not arise because worlds and -verses are entirely different beasts. One is impossibly F, and the other is possibly F. But, at this point, I am sorry to say that I've lost the thread of the discussion.

  14. Ah, I think I see now. It is certainly a reasonable position to think that only our one universe or only one set of multiverses is concrete and "possible worlds" are not concrete. In that case, there is then a subsidiary question of whether "existence" is possible without concreteness in this sense (e.g., do numbers exist, and if so in what sense). Different understandings of "existence" can crosscut these scope specifications. So for example: You might think that only things that concretely exist genuinely exist. If you then think that "possible worlds" are not concrete, then you think that the cosmos is no larger than our own universe or multiverse. Yes?

  15. I took it that you wanted to remain at a somewhat noncommital level of discussion. Consequently, I was trying to use 'F' instead of something like 'concrete'. But let's stick with the property of concreteness and use 'K!' to denote that property.

    Let me regiment some of our discussion. I'd say only one -verse is K! but many are possibly K!. Moreover, I'd say worlds are impossibly K! (not just ~K!). Existence is another matter entirely. Individual x exists just in case there is an F such that x exemplifies F. Relation (or property) F exists just in case there are individuals that encode F. Proposition p exists just in case the property _being an x such that p_ exists (again, this comes from Zalta's Principia; but the errors, if any, are my own).

    Given the above, I can now illustrate how I'd answer, what I take to be, your two main questions.

    You ask about:

    > Possibly, there is an x such that x does not exemplify K!.

    Of course. Take any world w. It is impossible that w exemplifies K!, and yet w exemplifies the property _being a v such that impossibly v exemplifies K!_. Hence w exists (which is NOT to say w is the actual world!) and therefore possibly exists. We could say something similar about numbers. However, there are interesting nuances that I will not go into here. (For starters, it makes no sense to ask about whether numbers exist independently of a considered theory, which is another individual that is impossibly K!). In any case, I do not think only things that exemplify K! exist.

    You also ask about:

    > The cosmos is no larger than our universe or multiverse.

    I prefer to nix 'cosmos'. But if you think cosmos is possibly K!, then I'd have a hard time seeing the difference between a cosmos and a -verse. On the other hand, suppose we think of the cosmos more like the domain of everything that exists (which is constant across worlds). In that case, if the domain of everything that exists includes things that are contingently ~K! and things that are impossibly K!, then the cosmos includes more than a -verse.

  16. Good point on mathematics professor. Some clarification and adjustment is now in order.

    Mathematics may be considered a language based institution, which is to say this exists deductively rather than inductively. It’s the same with more advanced languages such as Italian (which evolved rather than were humanly developed). They all exist as cognitive tools and so will be causal under the premise of naturalism (or essentially here we presume they’re brain based constructs), though truth and falsity within such domains will exist beyond causality itself.

    So back to my single principle of metaphysics: “To the extent that causality fails, nothing exist to understand.”

    FALSE! As you’ve noted there will be no causal chain associated with understanding a mathematical idea for example. So given your observation, can my metaphysical principle be salvaged?

    Try this: “To the extent that causality fails, worldly dynamics do not exist to potentially understand.”

    Here I’ve confined my “understanding” claim to what I now consider a more appropriate though narrow domain. Instruments in mathematics and Italian may be said to exist deductively rather than inductively, or a priori rather than a posteriori.

    If so and we’re thus able to recognize the futility of trying to grasp worldly dynamics which are theorized to be somewhat beyond causality, we might then presume perfect causality on the grounds of pragmatism. Furthermore perfect causality mandates that all connected “universes” my be reduced back to a single perfectly determined larger universe that spawned them. The only naturalistic exception would be non causally connected realms of existence, which under your schema may effectively be presumed separate worlds under an overriding cosmos.

  17. Whereness has always lacked foundation, as even concrete foundations are temporary...
    ...but a philosophy book that might include at least a paragraph, towards reconciling the weirdness of whereness with hereness...
    ...could be an attempt, to correct, now in our time, where we came from and where are we going..

    Well, would be interesting to me...great reads, thanks...

  18. Wes: I'm reading you as liberal about "existence" and conservative about "concreteness", which is an attractive and defensible combination, though I could also imagine liberal-liberal and conservative-conservative as workable combinations (not to mention more complicated views). The framework I've advanced, combined with a clearer specification of what "concreteness" amounts to, then allows us to map out these alternatives. In laying out this broad framework, as you've surmised, my preference is not to commit to an single correct one. Rather, I aim to provide a structure for thinking about a range of possible philosophical views.

    Philosopher Eric: “To the extent that causality fails, worldly dynamics do not exist to potentially understand.” I'm not sure about this either. Consider an ordinary calculator: Here, worldly dynamics (the digits on the screen, contingent upon our button presses) help us understand (arguably) noncausal arithmetic relationships. On multiverses in particular, one potential argument -- which might succeed or fail, but which seems not a priori absurd -- is an inference to the best explanation of what appear to be fine-tuned cosmological constants. The idea here, of course, is that we can explain how "lucky" it is that there's a universe so well-tuned for intelligent life by appeal to an infinite of universes with every possible set of cosmological constants and then the Anthropic Principle according to which it's no coincidence that we happen to exist in one capable of hosting intelligence. Would this be a noncausal but still empirically-grounded defense of multiverse theory?

  19. I suggest you start with work (if only as a foil) that has been done as a scaffold to answer your scope questions. Pick any metaphysical -ism that purports to (at least) describe our -verse as F (whether or not F = K!). Treat worlds as individuals that are impossibly F and that contain all that exists. All that exists includes those -verses that are contingently not F and things like worlds themselves that are impossibly F.

    Now think about the -ism as applying to our -verse vs. applying to all worlds—for example, select materialism. Materialism at least claims that our -verse is material (F = material) and presumably has some way of cashing out that property. Is materialism also a thesis about all worlds? That is, is it the case that the non-material -verses at the actual world are material at other worlds, according to materialism? Or does materialism allow that there are non-material verses at other worlds?

    Your original post suggested that thinking about the scope of metaphysical -isms in this vein was something you are after. I wanted to suggest that current frameworks, like the most straightforward quantified modal logic, is used to think about what interests you. Does that help? Perhaps I've misunderstood.

    Here is one thing that is potentially interesting about the above framework for materialism. It is defined within the backdrop of a dualistic metaphysics. That metaphysics fundamentally includes individuals that are possibly material and individuals (like worlds) that are impossibly material. Another option is to treat worlds as individuals that are impossibly K! and that contain all that exists. Materialism at least claims that our -verse is material (where F = material but F might or might not be K!). Here materialism is still defined within the backdrop of a dualistic metaphysics. That metaphysics fundamentally includes possibly concrete individuals and individuals (like worlds) that are impossibly concrete. Here it is potentially interesting to think about the relationship between the properties:

    _being a v such that v is F_,
    _being a v such that v is not F_,
    _being a v such that v is possibly F_,
    _being a v such that v is impossibly F_,
    _being a v such that v is K!_,
    _being a v such that v is not K!_,
    _being a v such that v is possibly K!_, and
    _being a v such that v is impossibly K!_.

    I think that's potentially interesting since things like materialism are typically thought of monistically. But perhaps their scope is restricted in another sense. They've got to assume impossibly K! (or impossibly F) things like worlds in the background (if they are part of a modal metaphysics). They only apply to those things that do not exemplify those properties we might associate with the term 'abstract'. We can probably say the same for idealism and other such -isms, but I haven't thought about the implications here. I am just tossing it out there.

  20. ...apologies: I said:

    "That is, is it the case that the non-material -verses at the actual world are material at other worlds, according to materialism? Or does materialism allow that there are non-material verses at other worlds?"

    But that's not clear at all! Of course, they must allow that there are non-material verses at worlds. I should have said:

    "That is, is it the case that, for all worlds w1, there is a -verse that is not material at some world w2 but material at w1, according to materialism? Or does materialism allow that there is a world w such that no -verse is material?"

    Thanks, in advance, for letting me clarify.

  21. > That is, is it the case that, for all worlds w1, there is a -verse that is not material at some world w2 but material at w1, according to materialism? Or does materialism allow that there is a world w such that no -verse is material?

    Also of interest: Those questions implicitly assumed that there are multiple -verses (which is to say it assumed multiple universes and multiple multiverses) in the domain of all that exists. Do materialists only admit one -verse in the domain? If so, for all worlds, is that -verse material, according to materialism? Suppose they only admit one -verse in the domain, and they answer the previous question in the affirmative. In that case, necessarily, there are no immaterial -verses (not even contingently immaterial -verses), according to them. Or does materialism allow that there is a world such that the -verse is immaterial?

    Sorry for the spam. As I said, I find this interesting.

  22. Professor,
    Instead of referring to mathematical relationships as “noncausal” (which to me has a supernatural connotation), perhaps we could refer to them as “beyond causal”? So here 2 + 2 = 4 would not merely be true by means of causality, but by means of definition itself given the nature of this particular language. All languages exist as constructs of what’s able to think them. Furthermore you and I presume that these thinkers are always natural (and even if not inherently biological).

    In this light there doesn’t seem to be anything strange about a machine that helps teach us about the humanly fabricated language of mathematics, as well as the evolved language of English, or any other. More important to me however is that my newly improved metaphysical principle seems to pass your second test — causal machines which help teach us about mathematics do not provide us with noncausal (or supernatural) understandings of worldly dynamics. Without a causal chain behind them worldly dynamics seem impossible to grasp, so even if sometimes true, why theorize supernatural solutions to our most troubling questions?

    There are plenty of people in academia who do take this route however, and rarely advertised as such. If we had a community of respected professionals asserting that it’s not possible to grasp that which lacks a causal chain, I think they’d help better found the institution of science by giving us both “natural” and “natural plus” varieties.

    On universes with different cosmological constants than ours, surely these would need to be supernatural? Presumably our cosmological constants work, not because they’re the right ones to produce us out of a multitude of existing universes with constants that wouldn’t, but because of causality itself. Though it does seem impressive to me that everything appears lined up to produce us, my naturalism mandates that I not fabricate supernatural universes as an explanation for our existence.

    “Would this be a noncausal but still empirically-grounded defense of multiverse theory?”

    Yep that’s exactly the case that some scientists are able to make. And while today they’re able to do so from standard science, my metaphysical principle would put them under a supernatural variant (that is if adopted by a sufficiently prestigious community of professionals).

  23. There are still more exciting things to consider! Some of the global -isms you seem to be investigating are affected depending on what additional axioms for necessity we choose. Indeed, perhaps we may characterize some of the -isms as accepting or rejecting certain axioms for necessity. (Suppose we've already accepted the simplest S5 axioms.)

    For example, suppose we take the following as axiomatic:

    > There is an x such that x is concrete but possibly not concrete.

    On one interpretation, this wouldn't be an axiom that an idealist accepts. That axiom _a priori_ implies that there are concrete objects, and, so, idealism would be refutable _a priori_. Must a materialist accept this axiom?

    Suppose, instead, that we take the following as axiomatic:

    > Possibly, there is an x such that x is concrete but possibly not concrete, and, possibly, there is no x such that x is concrete but possibly not concrete.

    Here the choice implies that there is a world in which there are no contingently concrete individuals. But a naturalist might not accept this. If naturalists say that impossibly concrete (abstract) individuals are (or are realized by) patterns of contingently concrete individuals in the world, there would have been no abstract individuals if there had been no contingently concrete individuals. However, abstract individuals exist in every world. Is the above axiom a way of characterizing some Platonists?

    Suppose we take the following as axiomatic:

    > Possibly there is an x such that x is concrete, and possibly there is no x such that x is concrete.

    Here, the choice implies something in addition to the one before. As before, it implies that there is a world where there are no contingently concrete individuals. But it also implies that there is a world where there are no necessarily concrete individuals. For example, suppose Spinoza is correct that the -verse is necessarily concrete. In that case, it would be incorrect to _a priori_ assert that there might be no concrete individuals. But, maybe many -isms would be willing to choose this axiom and deny Spinoza's thesis.

    Of course, some choices seem to imply fewer commitments:

    > Possibly, there is an x such that x is concrete but not _actually_ concrete.

    > Possibly, there is an x such that x is concrete but possibly not concrete.

  24. Thanks, Wes -- very interesting thoughts! You are right that my original motivation is to think about varying strengths of "-isms". The immediate triggering cause was actually thinking about solipsism as coming in various possible strengths; but of course materialism is a super relevant and arguably more important case. I've always been a little on the fence about / confused about materialism because it's generally regarded as a thesis with some sort of strong modal (e.g., "metaphysical") force -- and that brings us into metaphysical questions, such liberal vs restrictive interpretations of "exists", and conceivability tests, that seem somewhat counter to the scientific, merely nomological motivations of the type of materialism I find attractive.

    As you say:

    "I think that's potentially interesting since things like materialism are typically thought of monistically. But perhaps their scope is restricted in another sense. They've got to assume impossibly K! (or impossibly F) things like worlds in the background (if they are part of a modal metaphysics)."

    One potential advantage of this framework would be to assert materialism for the universe and then declare neutrality about broader scopes.

    On contingently concrete individuals: This might depend too on how one thinks about existence. A conservative about existence might think that things need to be concrete to exist, or at least that *individuals* (as opposed to properties or abstracta, or whatever) need to be concrete to exist. But here I start to wander into reaches of modal metaphysics beyond my usual range of expertise in philosophy of mind.

  25. I think one would be hard-pressed to give a good account of scientific reasoning without recourse to modal metaphysics and the metaphysics of abstracta. Over my admittedly short career, I witnessed many philosophers and philosophers of science try to do just that. Still, I don't think they can be successful. Naturalism, physicalism, and the like are conceived in a way that makes little sense of actual science (practice and theory) to my mind. But I realize those ideas are controversial. Top phil sci journals sometimes rejected my papers simply because one of the paper's premises was that abstracta exist (albeit in a deflated sense). Philosophy of science still has strong overtones of pop-positivism.

    You say:

    > On contingently concrete individuals: This might depend too on how one thinks about existence. A conservative about existence might think that things need to be concrete to exist, or at least that *individuals* (as opposed to properties or abstracta, or whatever) need to be concrete to exist.

    I fully accept that the stuff I've been throwing your way is relative to some metaphysical choices. A conservative might think that contingently non-concrete individuals don't exist. And they will have made different choices for which a distinct set of propositions are true. But I think at least considering Zalta + the most straightforward quantified modal logic re your (less committal) framework is worth your time. That was my main initial point. The rest was just because I was genuinely interested in thinking about this stuff. So, I'm looking forward to the book!

    I also have two additional clarificatory thoughts. First, I think the appropriate distinction is between being impossibly concrete (or abstract) and possibly concrete. It is not between impossibly concrete (or abstract) and concrete. Second, Zalta's theory eventually becomes typed. Properties are higher-order types than individuals. As individuals can either be possibly concrete or not, so can properties. You just have the properties of being impossibly concrete and of being possibly concrete at each level. His stuff is interesting here, and I actually think you could make use of it regarding realities.

  26. What would compliance to 'nomological motivations' look or sound like, sense or feel like, experience or be like...attention, intention, attitude....

  27. This link on 11/03/2020 at (Cognition_and_the_Evolution_of_Music_Pitfalls_and_Prospects)...
    ...furthers nomology for laws/orders in our universe, to minds when in tension, probably to anything in nature when in tension"...

    Finding/engaging the rhythms of life for understanding life...thanks for the reads...