such that no one of the above can be removed and the model stand, and if we then empirically verify the unknown material field (in, say, a particle accelerator), would that justify some credence in the immaterial one? I'm inclined to think it does. — Kenosha Kid

Is it possible to think of a model that would rely on an immaterial field that cannot be removed for the model to hold? Per definition the immaterial field doesn't effect anything material, so how could it then be necessary for the model if it doesn't effect anything?

I’d say that the non-coupling field is still actually a physical (better term than “material”) thing that we can indirectly detect, because it is an implication of the best explanation for the things we can directly detect.

If we were to be really strict about it, all we can direct detect are the immediate occasions of our experiences. Everything else, from rocks and trees to electrons and quarks, are abstraction the existence of which we posit because they serve a role in the best available explanation of those experiences. So if the best explanation for our experiences includes features we can’t experience, then those features are allowable even on the strictest physicalist account.

Things like other possible worlds fall into this category too. If the best explanation for the actual world involves there being infinitely many possible worlds of which the actual one is the only one we have experiential access to, then okay, it looks like there’s infinitely many possible worlds, even if we can’t experience them, because the negation of that fits worse with experience.

Is it possible to think of a model that would rely on an immaterial field that cannot be removed for the model to hold? Per definition the immaterial field doesn't effect anything material, so how could it then be necessary for the model if it doesn't effect anything? — ChatteringMonkey

I had in mind something like Kaluza-Klein theory, which fulfilled the first criterion (unifies known physical law) and also predicted a new field that was never found. Despite its attractiveness, it is deemed unscientific. But if it had predicted another field that was discovered, I imagine it would have been accepted, and would have had a big impact on our common understanding of the universe (e.g. that it is 5D, not 4D).

Things like other possible worlds fall into this category too. If the best explanation for the actual world involves there being infinitely many possible worlds of which the actual one is the only one we have experiential access to, then okay, it looks like there’s infinitely many possible worlds, even if we can’t experience them, because the negation of that fits worse with experience. — Pfhorrest

Yes, the thought didn't even occur to me. I suppose the difference is that the hypothesised field is still local, mooching around about, getting up to its undetectable mischief.

I take your point that we still know something about it through physics, that whatever would necessitate its co-existence with observable fields would constitute some kind of very indirect observation after-the-fact. However it is still only a model: we can seek another without recourse to undetectable fields that yields the same predictions, and if we find it apply Occam's razor without new empirical evidence. Does not finding such a model make undetectable fields more real to us, or is it simpler to assume we don't have the best model?

I'm mainly trying to figure out what it would take to convince me that something undetectable might exist. I'm gonna mull your argument, but I think I might agree: it is still detectable, albeit in a different way.

However it is still only a model: we can seek another without recourse to undetectable fields that yields the same predictions, and if we find it apply Occam's razor without new empirical evidence. Does not finding such a model make undetectable fields more real to us, or is it simpler to assume we don't have the best model? — Kenosha Kid

Well I guess that depends on how you would define simplicity. Some would probably say a less complex mathematical model is more simple, while others might say less empirically unverifiable stuff is more simple. This doesn't seem like a question there is definite answer to.

However it is still only a model: we can seek another without recourse to undetectable fields that yields the same predictions, and if we find it apply Occam's razor without new empirical evidence. — Kenosha Kid

Yes of course. But the same is in principle true of basically everything. The objects that we infer to exist from our experiences are all models, and if we should come up with better models according to which we don’t need to posit the existence of such objects, we’re free to revise our beliefs and do away with supposing that they exist.

Well I guess that depends on how you would define simplicity. Some would probably say a less complex mathematical model is more simple, while others might say less empirically unverifiable stuff is more simple. This doesn't seem like a question there is definite answer to. — ChatteringMonkey

Yes, another might be good old-fashioned inertia: we're sticking with the first thing that came along without empirical reason to abandon it. I suspect there's been a lot of that.

Yes of course. But the same is in principle true of basically everything. The objects that we infer to exist from our experiences are all models, and if we should come up with better models according to which we don’t need to posit the existence of such objects, we’re free to revise our beliefs and do away with supposing that they exist. — Pfhorrest

I get what you're saying, but this is qualitatively different insofar as it depends on undetectable things: it would be the first theory to be considered an empirically-verified scientific theory to do so tmk.

There is perhaps nothing stopping us from adding the new field by hand to the Standard Model, abandoning whatever physical considerations that yielded the model in the first place as now unscientific. I would imagine that would be an unpopular route (not least because the SM is itself symmetric, but nor is it completely ab initio, so...). This would then put the model in the same-place as Kaluza-Klein theory: admirably unifying, attractive, but no longer empirically-verifiable.

Or in other words, if a more reductive theory of the universe yielded observable phenomena but also unobservable phenomena, it might be justified to just incorporate the observable stuff into a less simple model of the universe at the expense of the otherwise perfectly viable, simpler theory.

Your OP doesn’t really address what the title suggests, namely, immaterial substance.

I bring that up because the use of the term ‘substance’ in philosophy is different to the everyday use of the term. It was originally used as the Latin translation ‘substantia’ for the Greek ‘ouisia’ which was found in Aristotle’s metaphysics. And in that context, ‘substance’ means ‘the bearer of attributes.’ A stock example is that Socrates’ having blue eyes, which are ‘accidents’ of the substance ‘Socrates’. So in this context, ‘substance’ means something nearer to ‘being’ than to ‘stuff’. Classically, the significance of a substance was the sense in which was not dependent on something else for its being, whereas, plainly attributes can only inhere in a substance.

In philosophy, a dominant model since Descartes has been the division of the world into res extensa, matter, and res cogitans, literally ‘thinking substance’. On that is based the idea of the world as ‘mind and matter’ which somehow interact.

But this was complicated by the parallel introduction in early modern philosophy of the primary and secondary attributes of particulars (by John Locke, and also by Galileo), which carves up the territory in a different way. Here, ‘primary attributes’ are those that are said to be inherent in an object, specifically the attributes measured by the then-new physics of Galileo such as solidity, extension, motion, number, etc. ‘Secondary attributes’, then, were those that were said to be in the mind of the perceiver - color for example - rather than inherent in the object.

This way of looking at things became the dominant model in modern thought generally, meaning that the notion of ‘substance’ in the earlier sense of ‘substances, modes and attributes’ fell almost entirely out of use. This naturally lead to the conception that the universe can be understood wholly and solely in terms of the objects of the physical sciences, ‘bearers of primary qualities’, which is the underlying paradigm of scientific materialism. Within that paradigm, the idea of a ‘thinking substance’ or an ‘immaterial substance’ is nonsensical, as no such object can be demonstrated.

But the very subtle, underlying point is not actually a difference over what exists, but a different conception of the nature of reality, from a shift to the conception of being, modes and attributes, to a conception of the sole reality of bodies. But that is an inevitable consequence of the way the territory was divided in early modern science, which is still playing out.

"Material" here is in the contemporary sense that if it is affected by and/or affects material things — Kenosha Kid

Self-referential definition? Try, ". . . and/or affects physical objects"

Your OP doesn’t really address what the title suggests, namely, immaterial substance.
...
This naturally lead to the conception that the universe can be understood wholly and solely in terms of the objects of the physical sciences, ‘bearers of primary qualities’, which is the underlying paradigm of scientific materialism. Within that paradigm, the idea of a ‘thinking substance’ or an ‘immaterial substance’ is nonsensical, as no such object can be demonstrated. — Wayfarer

Yet you got from classical Greek meaning of 'substance' to the very raison d'etre of my question yourself! :) The quality in question is undefined. It can be squareness or happiness for all I care. The point was, is demonstration that it should exist sufficient to justify belief in it, even though we cannot demonstrate it itself.

The point was, is demonstration that it should exist sufficient to justify belief in it, even though we cannot demonstrate it itself. — Kenosha Kid

Reference, or inertial, frames? They are immaterial, but they make perfect sense, and without them, SR is mighty hard to explain.

Reference, or inertial, frames? They are immaterial, but they make perfect sense, and without them, SR is mighty hard to explain. — Mww

That is true, but I included spacetime under the material category because I can do an experiment with material objects to determine e.g. the time difference between two events for me and for you (muon decay experiment, for instance). Beyond that, I don't interpret relativity as saying that reference frames have any ontological value. They are a useful tool for doing relativity, and as such I think fall under the broad category of human ideas, encodable in materials, and likely encoded in materials when being considered or memorised.

And perhaps that's all my hypothesised immaterial substance is: an idea that helps one to think about reality by casting it in the only available simplified mathematical model, itself merely a tool to account for the properties of matter.

Do you agree that the general theory of relativity exists?

Do you agree that the general theory of relativity exists? — Wayfarer

Yes, in books, brains, lecture notes, academic papers. In lots of places. :)

Any theory stated exists. Sufficiently conforms with scientific law enough at least to the person asked, well, we await the answer.

Yes, in books, brains, lecture notes, academic papers. In lots of places. — Kenosha Kid

So if there were none of these, would e still equal mc²? Do such facts only come into existence when discovered by us?

So if there were none of these, would e still equal mc2? Do such facts only come into existence when discovered by us? — Wayfarer

The laws underpinning or being (perhaps approximately) described by theories would not seem to me to come under the definition of unambiguously immaterial substance, since they ate indirectly observable, i.e. they effect matter. This is why I tried to be careful in limiting consideration to undetectable things.

I don’t think of them as ‘substances’ at all, but as principles and regularities.

They are a useful tool for doing relativity, and as such I think fall under the broad category of human ideas, encodable in materials, and likely encoded in materials when being considered or memorised. — Kenosha Kid

What this doesn’t allow for, is the fact that they enable predictions regarding things, about which we had no previous knowledge. They can’t simply be in the mind, as they’re efficacious and predictive with respect to objective phenomena. Nor, I think, peculiar to humans, as presumably the same principles would be discoverable by other intelligent beings.

Mathematical Platonism posits that there are real ideas, that is, ideas that are the same for any rational intelligence - such as e=mc² - but that are only graspable by a rational mind. Ergo, real but incorporeal. I think that is the direction one ought to be looking for something approaching immaterial realties, if not ‘substances’, as such.

What this doesn’t allow for, is the fact that they enable predictions regarding things, about which we had no previous knowledge. They can’t simply be in the mind, as they’re efficacious and predictive with respect to objective phenomena. — Wayfarer

This is an unrelated and rightly disputed claim. The wording of the OP was precisely to avoid the necessity of deciding whether phenomena like human ideas are material or not. The "Materialism and consciousness" thread is an obvious home for this sort of discussion. Here, if it is predictive, it is considered by the definitions in the OP to be material in the modern sense.

The wording of the OP was precisely to avoid the necessity of deciding whether phenomena like human ideas are material or not. — Kenosha Kid

I think that’s because it’s a fact that is inconvenient to naturalism. It’s the crack in the egg.

I think that’s because it’s a fact that is inconvenient to naturalism. It’s the crack in the egg. — Wayfarer

It arose out of the idea, espoused by myself on said thread, that if a thing does not interact with matter at all, belief in it is unjustified. This thread takes a special case of some abstract thing that, perfectly allowably in a fundamental physical model, does not couple to any material. That was what interested me; that is why I asked that specific question. The "Materialism and consciousness" thread perfectly covers what interests you, and I can battle it out with you over matters of mind there if you like :)

I don't interpret relativity as saying that reference frames have any ontological value. — Kenosha Kid

But your criteria says spacetime, being affected by material objects, is under the purview of the material world, and, if inertial frames are only contained by or in spacetime, it would appear such frames are every bit as affected by material objects, thus also under the purview of the material world, suggesting an ontological value.

But a reference frame cannot in itself be detected, and isn’t even a valid concept with respect to any single spacetime object anyway, but only in relation to another one separated from it, so it must be an “unambiguously immaterial substance” for which the belief “is unjustified, because they makes no impression on us and we can’t talk about them.” But they do, and we can, so......

But I agree: reference frames are unambiguously immaterial fields; I agree they do not exist as material objects exist, hence have no dedicated ontology; I don’t agree they have no ontological value.

I understand the limitive “contemporary criteria”. I don’t think a productive dialectic is possible using it alone. But interesting notion, nonetheless.

But your criteria says spacetime, being affected by material objects, is under the purview of the material world, and, if inertial frames are only contained by or in spacetime, it would appear such frames are every bit as affected by material objects, thus also under the purview of the material world, suggesting an ontological value. — Mww

Referring to the emphasised section, I'm unaware of anyone saying that spacetime contains reference frames. Reference frames are a mathematical tool for describing spacetime and the moving bodies within it. It is an artefact of these tools that an origin and some scales must be chosen to realise that utility, and these are arbitrary unless one specifically desires to consider a particular body to be in fact at rest, such as a laboratory or a hypothetical twin. What we detect is the phenomena that reference frames in relativity are so good at describing, such as the observer-dependence of whether the motion of a freefalling body is linear or parabolic, the discrepancies between accurate clocks close to or far from the Earth's surface, or the velocity-dependence of decaying unstable particles. These are frameworks within which we can ask insightful questions, i.e. ideas, rather than anything physicists consider to be out there somewhere. As ideas, they are again existing in minds, books, papers, lecture notes, memories, etc. and as such influence matter.

But the whole point of relativity is that physical laws are not in terms of frames. If I wish to state coordinates, I can only do so with respect to frames. But the vectors themselves are invariant under frame transform, and it is those that dictate the particular manifestation of physical law under study.

I'm unaware of anyone saying that spacetime contains reference frames. — Kenosha Kid

If I wish to state coordinates, I can only do so with respect to frames. — Kenosha Kid

All I’m saying is some “unambiguous immaterial substances” seem to be quite justified. Unambiguous and immaterial being uncontested, substance being not so lucky.

All I’m saying is some “unambiguous immaterial substances” seem to be quite justified. — Mww

Well, I'd say not in this case. The idea of reference frames strikes me as material, as does the actual thing it represents. You might, if you were an idealist for instance, disagree. That was precisely the ambiguity I sought to exclude, although, as Pfhorrest pointed out, it could be argued that my hypothetical example suffers another ambiguity.

OK.

I like to think that we are aware of only one form of reality - that of spacetime. So possibly or maybe or likely there are many other forms of reality - states of existence that may not even involve space-like or time-like constructs - such realities would exist no time and no distance from our universe.

OK. — Mww

I feel bad, like I've offended you somehow, but I'm not sure if that's because my partner has conditioned me to take "OK!" as "I'm angry!" :rofl:

Nope, not offended. I cherrypicked from your criteria and conditions, so rapidly exhausted my potential argument.

The idea of reference frames strikes me as material, as does the actual thing it represents. — Kenosha Kid

In what sense are ideas material? If I asked you to send it to me, or show it to me, would you be showing me a material thing, with mass, and so on? I will answer that for you: no, you would be showing me a set of symbols, and trying to explain their meaning. If I couldn't read those symbols, or grasp their meaning, then I you would not be able to 'convey the idea'. Therefore, the idea is not material.

Quick defining of terms.

"Material" here is in the contemporary sense that if it is affected by and/or affects material things, it comes under the material world's purview (e.g. spacetime, electric fields, etc.) In short, if we can detect it, even indirectly, it gets classed as material. — Kenosha Kid

The idea of reference frames strikes me as material, as does the actual thing it represents. — Kenosha Kid

As you know, reference frames are a formalism that abstract over the systems they stand for. Physicists use that formalism to say that when you do this experiment, this outcome is predicted.

It is those observable systems that ground the formalism.

Now you're just saying that that grounding and use is what makes them material - physicists couldn't explain their experiments without them.

That's OK. But it doesn't quite fit your definition above. A reference frame isn't itself detectable, it's instead part of the formal machinery that physicists use to detect things.