The distance (amount of space) between any two things at some "point in time" is not dependent on perception, even though the measurement of that distance can be said to be so. — Janus

As regards the second point, yes, the actual measurement of distance between two points in space is dependent on human observation.

But as regards the first point, what is the true reality of the space between two points?

What is empty space?

Even if there is no empty space and every part of the universe contains fluctuating energy fields, what is the nature of the space that contains these fluctuating energy fields?

Was Newton right, that space is an absolute existing independently of any objects within it, or was Leibniz right that space is only defined by the relation of objects within it?

He admits that things in themselves act on us, on our senses. — W. Norris Clarke - The One and the Many: A Contemporary Thomistic Metaphysics

Given that the subject of this particular passage is Kant’s theory, it follows that in “he admits”, he is Kant. However, in A493/B522 is found….

“… For I can say only of a thing in itself that it exists without relation to the senses and experience.…”

….which makes patently obvious Kant admits to no such thing.

It is profoundly contradictory, and destructive to the Kantian form of transcendental metaphysics, for the thing in itself to act on human senses. If the thing in itself appears to us, which just is to act on our senses, the very concept itself is invalid.

OR…..I would greatly appreciate being informed of where I can read, in first-hand texts only, that he admits….or even hints….in accord with Clark’s statement.

The other thread reminded me of another contributor here. There was also an explosion in logical work in the late middle ages. Partly, this is because the univocity of being allows logic to "do more" because there is not this supposition that in the context proper to metaphysics we are generally speaking of analogy (in the one being realized analogously in the many, or "analogous agents" causation). Nominalism also does some things to make it seem like logic is more central. No longer can natures explain divine action. God can "make a dog to be a frog" rather than "replacing a dog with a frog" or some sort of accidental change ("making a dog look like a frog"). Wholly (logically) formal contradiction becomes the limits of possibility. This is also when the embryo of possible worlds with Buridan starts, rather than modality being defined in terms of potentiality.

All this makes logic more central, and then logical solutions come to drive metaphysics. So, Ockham has the idea that problems with identity substitution related to the context of belief can be resolved by claiming that references in belief statements suppose for the believer's "mental concept" or a thing rather than the thing simpliciter (restriction). But this neat logical move is then taken as prescriptive for metaphysics and epistemology, and you get "logic says we only ever know our own mental concepts," (representationalism).

This is all compounded by the context of the Reformation and Counter Reformation, because the focus on logic to adjudicate arguments becomes even more intense.

Guys like Pasnau and Klima put it this way, logic comes to colonize metaphysics.

You can also see this in the primary/secondary properties distinction. Originally, it is quantity, magnitude, i.e., the common sensibles, which are secondary. And they are merely "secondary" in terms of not being the primary formal object of any one sense. But this gets flipped, so that mathematics (obviously univocal in this context) becomes primary, and the secondary also becomes in a sense illusory, a sort of projection.

My intention was that from the viewpoint of a human observer, even in a deterministic world, they cannot know the future. — RussellA

All right then, let's start from this premise. If a human observer cannot know the future, but can know the past, this implies a real difference between future and past. How can a determinist adequately account for this difference?

The free will believer understands that the future holds possibility, therefore the epistemic concept of truth and falsity is not applicable to the future. This accounts for that difference. So this difference is actually very simple to understand when we employ the right premise.

We don't need to know whether Newton's Laws apply to those parts of the Universe that we don't observe, we only need to know that they apply to the parts of the Universe that we do observe. — RussellA

If the determinist laws (the laws of physics which support one's belief in determinism), are not believed to extend to all parts of the universe, then how is the belief in determinism supported. Wouldn't it be possible that nondeterministic activity reigned in some part of the universe, and there could be some interaction between the various parts?

Remember, the principle you are supporting is superdeterminism, and this theory requires interactions with that other part of the universe, as hidden variables. The question is, what supports the belief that the supposed hidden variables are deterministic. The deterministic laws which we know, are Newton's laws. If the hidden variables are not acting according to Newton's laws, then why believe that they are deterministic?

I suggest to you, that you consider the basis of determinism, the primary premise, to be the inertia of mass, (matter), which is expressed by the first law. A person who believes in free will, and the reality of the immaterial in general, does not allow that Newton's first law extends to a living body moved by final cause. Also, this person is easily able to see that the problems of quantum mechanics arise from the physicists' experimentations which involve the massless, the immaterial. It is this determinist bias which you demonstrate, which makes people want to establish compatibility between Newton's deterministic laws, which apply to massive material bodies, and the massless immaterial substratum.

However, this is backward. Since the immaterial is the substratum, this means that the deterministic, the material aspect is what emerged from the immaterial. This implies that we need to understand the reality of the non-deterministic immaterial aspect of the universe first, and determine how a deterministic, material aspect could have come into being from it.

It seems that in In God's Will, the changes a human makes to their present are determined by the final cause, the unmoved mover. A human's will is free providing they use their will to move towards this final cause, this unmoved mover. — RussellA

I don't think that is correct. The concept of free will allows that we choose freely. This means that we can choose either way, bad or good, so we do not necessarily choose according to "God's Will". "God's Will" is a concept used to explain why material bodies of mass move in an orderly, deterministic way, in a universe where the substratum is non-deterministic. If, for example the universe is assumed to have begun as endless possibility, infinite potential, and some process started selecting from possibilities to create the actual universe, we need to assume some form of intelligence (Will of God for example) to account for the emergence of actual order, from the seemingly endless possibility. Without any intelligence, possibility would actualize in a random way, but this is inconsistent with our observations.

Yes, that is perfectly reasonable as an informal description of gravity when describing a particular case of motion in the concrete rather than in the abstract — sime

In language, one can justly say that "the force of gravity causes a stone to move towards the ground". Some of these words are figures of speech, some are concrete and some are abstract.
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as Russell observed, in such cases the concept of causality can be eliminated from the description. — sime

In physics, one can justly write that ${s = 0.5 * g * t^{2}}$. This equation predicts the position of the stone with time under a gravitational force. The concept of cause within the equation is redundant.

But a sentence and an equation are very different things. The sentence is about why something happens, "why did the stone fall towards the ground, because of the force of gravity". The equation is about how the stone falls towards the ground, ${s = 0.5 * g * t^{2}}$.

It is true that the concept of causality may be removed from an equation, but not true that the concept of causality can be removed from language.
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But determinism takes the causal "determination" of movement by gravity literally, universally and outside of the context of humans determining outcomes — sime

From Britannica - Determinism

The thesis that all events in the universe, including human decisions and actions, are causally inevitable.

There is a difference between what happens and why it happens. Equations are about what happens not why it happens. Equations are about predictions not causes. It is true that Determinism, as Britannica notes, is the thesis that all events are casually inevitable, universally and outside any human observation.

The equation ${s = 0.5 * g * t^{2}}$ is about what happens, not why ${s = 0.5 * g * t^{2}}$.

Why ${s = 0.5 * g * t^{2}}$ is, according to Determinism, causally inevitable.
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and in a way that requires suspension of Humean skepticism due to the determinist's apparent ontological commitment to universal quantification over generally infinite domains. — sime

That all events in the universe are causally inevitable is the thesis of Determinism. A thesis is an hypothesis, not an ontological commitment. As a thesis, it accepts that it may be proved wrong, in the same way that the equation ${s = 0.5 * g * t^{2}}$ may be proved wrong. A thesis does not require a suspension of scepticism, which is why it is a thesis.

Both Determinism and the equation ${s = 0.5 * g * t^{2}}$ may be thought of as axioms, statements taken to be true or self-evident, and serve as a premise for further reasoning.

That all events in the universe are causally inevitable is the thesis of Determinism. A thesis is an hypothesis, not an ontological commitment. As a thesis, it accepts that it may be proved wrong, in the same way that the equation s=0.5∗g∗t2 may be proved wrong. A thesis does not require a suspension of scepticism, which is why it is a thesis. — RussellA

Actually that's untrue, because without ontological commitment to universal quantification over absolute infinity, one cannot distinguish the hypothesis of determinism from its anti-thesis.

What a hypothesis means is subject to as much uncertainty as its truth value. Unless one is already committed to the truth of determinism, one isn't in a position to know what the hypothesis of "determinism" refers to.

Actually that's untrue, because without ontological commitment to universal quantification over absolute infinity, one cannot distinguish the hypothesis of determinism from its anti-thesis. — sime

I have the belief that ontological Determinism is true, in that all events in the Universe can occur in only one possible way.

But I am not committed to my belief and have not suspended any scepticism towards my belief, because I accept that tomorrow someone using a persuasive argument may change my mind. I doubt it, but who knows.

However, for the moment, for me, ontological Determinism is a good working hypothesis.

Well, that's a thorny area in Kant scholarship, right? I have read many contradictory takes on the exact relation (or "negative" or "limiting" relation) between appearances and things-in-themseleves. Because Kant also makes it clear that appearances are of things, and is cognizant of the fact that if appearances bear absolutely no relationship to what they are appearances of, they would simply be free standing, sui generis entities (e.g. in the Transcendental Aesthetic). Although I know there are also more "subjective idealist" readings of Kant.

The things that we intuit are not in themselves what we intuit them as being [yet they are the "things we intuitive"]. Nor do their relations in themselves have the character that they appear to us as having. And if we annul ourselves as subject, or even annul only the subjective character of the senses generally, then this entire character of objects and all their relations in space and time-indeed, even space and time themselves would vanish; being appearances, they cannot exist in-themselves, but can exist only in us. What may be the case regarding objects in themselves and apart from all this receptivity of our sensibility remains to us entirely unknown. All we know is the way in which we perceive them.

A-42/B-59 (emphasis mine)

Also in the section you quoted:

hence what is in them (appearances) are not something in itself, but mere representations, which if they are not given in us (in perception) are encountered nowhere at all.

But representations are still representation, not sui generis free standing actualities with absolutely no relation to what is being represented.

In the section after the one your referred to:

The non-sensible cause of these representations is entirely unknown to us, and therefore we cannot intuit it as an object; for such an object would have to be represented neither in space nor in time (as mere conditions of our sensible representation), without which conditions we cannot think any intuition. Meanwhile we can call the merely intelligible cause of appearances in general the transcendental object,' merely so that we may have something corresponding to sensibility as a receptivity.

(Emphasis mine)

What is meant by "unknown" exactly seems to be the cause of some controversy. Kant is obviously speaking about them at least. Obviously, this is not "cause" as in the categories, because he denies this in prior sections. In English I have seen "affectations" used as a placeholder word here so as to not confuse it with empirical causes. But I think the Scholastic objection would probably rest here on the generally deflated sense of causes as well.



Anyhow, by "action," (a poor word choice perhaps) I think it is clear that Clarke doesn't mean the knowable causal relation, or else he would have no qualms with Kant because Kant would merely be following the old Scholastic dictum that "everything is received in the manner of the receiver," and the old Aristotleian view that sensation is of interaction. But the Neoscholastic opposition to Kant is generally that he absolutizes and totalizes this old dictum.

Anyhow, what translation are you using? And is that the First Critique? I couldn't find that line. The closest rendering in that section I could find is in here:

in themselves, appearances, as mere representations, are real only in perception, which in fact is nothing but the reality of an empirical representation, i.e., appearance. To call an appearance a real thing prior to perception means either that in the continuation of experience we must encounter such a perception, or it has no meaning at all. For that it should exist in itself without relation to our senses and possible experience, could of course be said if we were talking about a thing in itself. But what we are talking about is merely an appearance in space and time, neither of which is a determination of things in themselves, but only of our sensibility; hence what is in them (appearances) are not something in itself, but mere representations, which if they are not given in us (in perception) are encountered nowhere at all.

These are the Cambridge one.

That's a very interesting post.

If a determinist wants to avoid being charged with being ontologically commited to Berkeley's Spirits in another guise, then he certainly cannot appeal to a standard game-semantic interpretation of the quantifiers. But then what other options are available to him? Platonism?

By "Platonism," do you mean the idea of natural laws as a sort of eternal, active "shaping" of causal interactions? That would be, in a sense, formally very similar, although it avoids the volanturist texture that I think many moderns find distasteful (although, it replaces them with apparent contingencies that seem to exist "for no reason at all," so it still has a volanturist feel).

I would think another option would be the causal theories of "Neoplatonism" in the broad sense that includes the Golden Age Islamic thinkers, late Patristics, and Scholastics. That avoids the lack of real, efficacious secondary causality tied to natures and the seeming volanturism that I find distasteful in Berkeley (I remember thinking he is more towards Malebranche’s occasionalism in some way).

The Book of Causes (which I think is now thought to be a product of Iberian Jewish Neoplatonism now, but the Scholastics loved it too) is a good comparison case here.

All good; thanks for taking the time, and I did give your response the attention it deserved.

Yes, first critique, and, translation used is Gutenburg’s J. M. D. Meiklejohn, ca 1856, for the simplicity of search + cut/paste, not available in my other IPad renditions.

And to a lesser extent, for seniority, in that I downloaded it to Kindle about a million years ago.

But most of all, for protecting the “FN” AB Bookman’s-conditioned Ex Libris Cambridge University 1929 first edition Kemp Smith, gold gilt on red leather and all….(don’t ask)

Useless trivia here aside, should I have found something in your response that shows I misunderstood Clark’s statement?

n language, one can justly say that "the force of gravity causes a stone to move towards the ground". Some of these words are figures of speech, some are concrete and some are abstract. — RussellA

You are still not getting the distinction I explained to you. What causes the stone to fall is gravity. "Force" is not an independent thing in the world which causes anything. "Force" is a mathematical concept, how we quantify the effects of things like gravity.

It really makes no sense to say "the force of gravity causes a stone to move towards the ground". When we analyze that statement, it's plain to see that "force" has no meaning here. What would "force" refer to here, some invisible, unobservable property of an invisible unobservable thing, gravity?

However, when someone says something like that we easily understand it, because we can just ignore "the force of", and understand it as "gravity causes a stone to move towards the ground". "Force" has no intelligible meaning in that context so it is simply ignored.

What causes the stone to fall is gravity. "Force" is not an independent thing in the world which causes anything. "Force" is a mathematical concept, how we quantify the effects of things like gravity. — Metaphysician Undercover

The equation ${s = 0.5 * g * t^{2}}$ describes the position of a stone above the ground dropped from rest with time under gravity.

We could say "gravity causes the stone to fall".

We can quantify the force of gravity. On Earth, the average gravitational force is about 9.81 m/s². On the Moon, it is about 1.63 m/s².

However, if gravity had zero force, 0.00 m/s², the stone would not fall.

So we cannot say that it is gravity per se that causes the stone to fall, but rather it is the force of gravity that causes the stone to fall.

So really, "it is the force of gravity that causes the stone to fall".

If a human observer cannot know the future, but can know the past, this implies a real difference between future and past. How can a determinist adequately account for this difference? — Metaphysician Undercover

Even someone who believes in Determinism may know their past but cannot know their future.
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If the determinist laws (the laws of physics which support one's belief in determinism), are not believed to extend to all parts of the universe, then how is the belief in determinism supported — Metaphysician Undercover

In the same way that mathematicians have a belief in the axioms they use, statements assumed to be true as a starting point for further reasoning.
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Wouldn't it be possible that nondeterministic activity reigned in some part of the universe, and there could be some interaction between the various parts? — Metaphysician Undercover

Yes, it is possible, but so far science does not seem to have found such nondeterministic activity.
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The question is, what supports the belief that the supposed hidden variables are deterministic. — Metaphysician Undercover

I am not a physicist, but I do know that there are some physicists that I trust, such as Sabine Hossenfelder, who do believe in Superdeterminism.
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A person who believes in free will, and the reality of the immaterial in general, does not allow that Newton's first law extends to a living body moved by final cause. — Metaphysician Undercover

On the one hand, some believe in Physicalism, that everything is physical, and there is nothing beyond the physical realm.

On the other hand, some believe in the immaterial.

It depends what is meant by the word "immaterial".

The article What Sorts of Things Exist, & How? writes

But the immaterial things are the philosophically more interesting. These include consciousness, thoughts, words, meanings, concepts, numbers, emotions, intentions, volitions, moral principles, aesthetic experiences, and more. What would philosophy be without them?

However, the article Immateriality of God writes

The immateriality of God simply means that God is not composed of material. In other words, God is not made of any kind of matter, material, or substance which entails that he cannot be seen.

There are different meanings to "immaterial".

Useless trivia here aside, should I have found something in your response that shows I misunderstood Clark’s statement?

Well, in the book (which is the only of his I've read) he only mentions Kant a few times. But I would gather given his general outlook that when he is speaking of things-in-themseleves and how they "act on" our senses, he just means this sort of limiting relation. "Act on" for him might have a Scholastic connotation of merely "has a prior actuality." But given what I recall him saying, and what he says here, I am pretty sure he means this in a fairly conventional way in Kant scholarship, where this relationship is merely that "representation" and appearances are "of something." The fact that sensation and understanding never contain anything of the things-in-themseleves is precisely what he is arguing against here. So he isn't denying the limits that Kant places on knowledge but rather that those limits make sense.

And on the Thomistic account, if you accept some of the other premises, I do think this critique is strong. Appearances cannot be arbitrarily related to what they are appearances of or else they wouldn't be appearances of those things (no wholly equivocal agents). The actuality in the mind is received according to what man is, but it has to be the same actuality/form that is in what is perceived (i.e., the actuality that moves potential experience to actual experience). If you start with Kant's assumptions, then his conclusions make more sense. So one has to consider the starting point.

Just from a genealogical standpoint though, the epistemic presuppositions that Kant inherits through Hume and others is based on a program that, in its original ancient form, is explicitly designed to terminate in skepticism so as to achieve dispassion. That a program designed with a goal of skepticism produced skepticism is in a way not that surprising.

We can quantify the force of gravity. On Earth, the average gravitational force is about 9.81 m/s². On the Moon, it is about 1.63 m/s². — RussellA

There is more than one thing involved in that formula which you call "gravitational force". There is space and time. The formula must be understood as conceptual, rather than something independent, because it unites these two features in an artificial way, conception. Notice that within the theory (conception) of general relativity, "gravity" is understood in a completely different way. It is not conceived of as a force, but as a property of spacetime. This is because space and time have already been united by the conception of special relativity, and this union must be adjusted to properly account for gravity. Therefore in general relativity gravity is already included into the conception of space and time. So we have two very different ways to conceive what you call "gravitational force". One is as a force, the other as a property of spacetime. The latter is distinctly not "a force".

Basically…

Mass-energy curves space-time — a new version of Hooke's law.
Objects trace out world lines that are geodesics (paths of least action in curved space-time) unless acted upon by a net external force — a new version of the law of inertia.
Gravity isn't a force, it's the curvature of space-time caused by the presence of mass-energy.

https://physics.info/general-relativity/

Even someone who believes in Determinism may know their past but cannot know their future. — RussellA

Right, so as I say, this presents us with a premise describing a real difference between past and future. Do you agree that this is a real difference? Can you agree that a person can know one's past and cannot know one's future, and because of this we ought to conclude that there is a real difference between past and future?

If we have agreement on this, then we can proceed to inquire exactly what this difference consists of.

The article What Sorts of Things Exist, & How? writes

But the immaterial things are the philosophically more interesting. These include consciousness, thoughts, words, meanings, concepts, numbers, emotions, intentions, volitions, moral principles, aesthetic experiences, and more. What would philosophy be without them?

However, the article Immateriality of God writes

The immateriality of God simply means that God is not composed of material. In other words, God is not made of any kind of matter, material, or substance which entails that he cannot be seen.

There are different meanings to "immaterial". — RussellA

I don't think those two examples constitute two different meanings. They are applying the same definition of "immaterial" to refer to different things. The definition is "not composed of material". In the first example there is thoughts, conception etc., and in the second there is God. Each case uses "Immaterial" in the same way, by the same definition.

We could add to that list of immaterial things, massless particles. And if such things are believed to be real, independent and not merely conceptual, then we'd have a belief in the real existence of the immaterial. Mass is the essential property of matter. However, many materialist/physicalists will insist that since there is a mass-energy equivalence then energy also is material. But this is a misunderstanding of "equivalence".

Equivalent means that equal things have been assigned the same value, it does not mean that the two things are the same. So if matter has mass, and energy does not have mass, therefore no matter,, and there is an equivalence between these two, this means that we have conceived of a mathematical relationship between the material and the immaterial. But it does not mean that the immaterial is material. We need to account for the specific postulates of that relationship.

So we have two very different ways to conceive what you call "gravitational force". One is as a force, the other as a property of spacetime. The latter is distinctly not "a force" — Metaphysician Undercover

Yes, there are at least two ways to think of gravity. One is as a force and one is as the curvature of space-time caused by the presence of mass energy.

The NASA article refers to the first way

Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun.

The article on General Relativity refers to the second way

Gravity isn't a force, it's the curvature of space-time caused by the presence of mass-energy.

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Can you agree that a person can know one's past and cannot know one's future, and because of this we ought to conclude that there is a real difference between past and future? — Metaphysician Undercover

I agree, there is a real difference between past and future.
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I don't think those two examples constitute two different meanings. They are applying the same definition of "immaterial" to refer to different things......................................And if such things are believed to be real, independent and not merely conceptual, then we'd have a belief in the real existence of the immaterial. — Metaphysician Undercover

I think you are are making a logical leap too far.

The Merriam Webster Dictionary defines "immaterial" as "not consisting of matter".

As photons don't consist of matter, they can be considered immaterial.

The article Immateriality of God writes

The immateriality of God simply means that God is not composed of material.

Premise 1 - God is immaterial
Premise 2 - Photons are immaterial
Premise 3 - Photons have a real existence

Conclusion - as some immaterial things have a real existence and as God is immaterial then God has a real existence.

Not sure a whole mini-dissertation is called for here, even though I just wrote one. I’ll just say I don’t agree with Clark, at the same admitting I am far from academically equipped to prove his complaint as unjustified. I might be able to find a veritable plethora of pertinent textual quotes that in my opinion suffice, but still the chance of barking up the wrong epistemological tree, remains.

Unless you’ve got something more you’d like to talk about…..

Yes, there are at least two ways to think of gravity. One is as a force and one is as the curvature of space-time caused by the presence of mass energy. — RussellA

In other words, "force" is purely conceptual. It is only one of a number of conceptions which can be applied toward representing the effects of gravity, but not the only one. "Force" doesn't represent gravity, it is a method of categorizing the effects of gravity.

I think you are are making a logical leap too far.

The Merriam Webster Dictionary defines "immaterial" as "not consisting of matter".

As photons don't consist of matter, they can be considered immaterial.

The article Immateriality of God writes

The immateriality of God simply means that God is not composed of material.

Premise 1 - God is immaterial
Premise 2 - Photons are immaterial
Premise 3 - Photons have a real existence

Conclusion - as some immaterial things have a real existence and as God is immaterial then God has a real existence. — RussellA

I don't understand what you are saying here. Last post, you listed some things which are believed to be immaterial, concepts, ideas, intentions, also God. I explained why massless particles ought to be included in that list, and suggested that if a person believes in the real existence of massless particles, then they believe in the real existence of the immaterial. I made no conclusion about God.

Personally, I believe that massless particles are nothing but an idea, a conception, and not real in the sense of independent. I think "photon" is a concept created in an attempt to explain the photoelectric effect. The problems of quantum mechanics demonstrates that "photon" is a faulty concept for explaining how light energy transmits. Therefore it is false, and not referring to anything independent.

.

As photons don't consist of matter, they can be considered immaterial. — RussellA

If matter just is energy then, then photons are material. Are electrons, protons and neutrons material in your opinion?

Conclusion - as some immaterial things have a real existence and as God is immaterial then God has a real existence. — RussellA

That would be an invalid inference.

If matter just is energy then, then photons are material. Are electrons, protons and neutrons material in your opinion? — Janus

I don't know.

Some physicists say that matter is just stable energy. For example, Wilhelm Ostwald regards energy as a form of substance.
https://readfeynman.blogspot.com/2017/04/section-41-what-is-energy.html

Other physicists say that matter is categorically distinct from energy. For example, Matt Strassler.
https://profmattstrassler.com/articles-and-posts/particle-physics-basics/mass-energy-matter-etc/matter-and-energy-a-false-dichotomy/
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That would be an invalid inference. — Janus

This is my point.

Other physicists say that matter is categorically distinct from energy. For example, Matt Strassler. — RussellA

That article also says unambiguously that photons are STUFF, like matter. So if we're going by that article, photons are material, as are electrons and protons and neutrons

That article also says unambiguously that photons are STUFF, like matter. So if we're going by that article, photons are material, as are electrons and protons and neutrons — flannel jesus

Yes, Strassler's article says that photons are material (stuff).

But energy is not itself stuff; it is something that all stuff has.
Photons are stuff; energy is not.

But, today, matter is commonly defined as something that has mass, meaning that a photon must be immaterial.

In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume (Wikipedia - Matter)

Whether a photon is material or immaterial depends on one's particular viewpoint.

In other words, "force" is purely conceptual. It is only one of a number of conceptions which can be applied toward representing the effects of gravity, but not the only one. "Force" doesn't represent gravity, it is a method of categorizing the effects of gravity. — Metaphysician Undercover

There are two ways of looking at it.

One way is that "gravity is a force". "Gravity" and "the force of gravity" are synonyms, as the hotness of a body is the motion of its constituent parts.

The other way is that "gravity has a force". Gravity can be quantified by a force, as the hotness of a body can be quantified by temperature.
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I made no conclusion about God. — Metaphysician Undercover

I think that the following is still relevant to Berkeley's Idealism and ‘esse est percipi’.

A photon is an example of a massless particle.

A massless particle may be defined as immaterial.

I agree when you say "and suggested that if a person believes in the real existence of massless particles, then they believe in the real existence of the immaterial"

I believe in the real existence of the immaterial.

But you also said "In the first example there is thoughts, conception etc., and in the second there is God. Each case uses "Immaterial" in the same way, by the same definition."

So, both photons and God are immaterial, where immaterial means the same thing.

But if a person believes in the real existence of photons then they believe in the real existence of the immaterial.

But if a person believes in the real existence of the immaterial, and God is immaterial, then should not a person believe in the real existence of God?

Whether a photon is material or immaterial depends on one's particular viewpoint. — RussellA

Sure, BUT if you're calling photons "immaterial" as if to compare them to something abstract, I think that's a mistake. Matter or not, mass or not, they're a part of physics.

I think "photon" is a concept created in an attempt to explain the photoelectric effect. — Metaphysician Undercover

That is the nature of language, where concepts are about the sense of things in the world rather than refer to things in the world (Frege).

Scientific language is full of figures of speech. Andrew May in Metaphors in Science 2000 makes the point that even Newton's second law is probably a metaphor.

"In his article on the use of metaphors in physics (November issue, page 17), Robert P Crease describes several interesting trees but fails to notice the wood all around him. What is a scientific theory if not a grand metaphor for the real world it aims to describe? Theories are generally formulated in mathematical terms, and it is difficult to see how it could be argued that, for example, F = ma "is" the motion of an object in any literal sense. Scientific metaphors possess uniquely powerful descriptive and predictive potential, but they are metaphors nonetheless. If scientific theories were as real as the world they describe, they would not change with time (which they do, occasionally). I would even go so far as to suggest that an equation like F = ma is a culturally specific metaphor, in that it can only have meaning in a society that practices mathematical quantification in the way that ours does. Before I'm dismissed as a loopy radical, I should point out that I'm a professional physicist who has been using mathematical metaphors to describe the real world for the last twenty years!"

Sure, BUT if you're calling photons "immaterial" as if to compare them to something abstract, I think that's a mistake. Matter or not, mass or not, they're a part of physics. — flannel jesus

But "photon" is a concept in the English language, and concepts are something abstract.

The sense of a concept is abstract. Its reference may be concrete, even if we never know the concrete reality.

From SEP - Concepts

An alternative conception of concepts takes concepts to be abstract objects of one type or another.

But "photon" is a concept in the English language, and concepts are something abstract. — RussellA

So is "chair", so is "photon", so is "atom". Have we now debased the word "immaterial" so much that EVERYTHING is now immaterial?

Words need boundaries. Words without boundaries are usually words without meaning. If everything is immaterial, the designation "immaterial" has no weight.

I think that the following is still relevant to Berkeley's Idealism and ‘esse est percipi’.

A photon is an example of a massless particle.

A massless particle may be defined as immaterial.

I agree when you say "and suggested that if a person believes in the real existence of massless particles, then they believe in the real existence of the immaterial"

I believe in the real existence of the immaterial.

But you also said "In the first example there is thoughts, conception etc., and in the second there is God. Each case uses "Immaterial" in the same way, by the same definition."

So, both photons and God are immaterial, where immaterial means the same thing.

But if a person believes in the real existence of photons then they believe in the real existence of the immaterial.

But if a person believes in the real existence of the immaterial, and God is immaterial, then should not a person believe in the real existence of God? — RussellA

Your conclusion doesn't follow. If I list off three item types which are said to be classified as the further type, class A, and you agree that item type number 3 is a type of real item, of class A, I can conclude that you believe that there is real items of class A. This in no way implies that you believe that item type 1, and item type 2, are real items.

Notice, class A stands by the same definition throughout. The issue is whether item type 1, item type 2, and item type 3, which are proposed as items which fit that definition, are real items. For example, I could say that horses and unicorns are of the class "four legged animals". If you believe in the reality of horses, you believe in the reality of four legged animals. But this does not imply that you believe in the reality of unicorns. And, "four legged animals" has the same definition throughout.

That is the nature of language, where concepts are about the sense of things in the world rather than refer to things in the world (Frege). — RussellA

I really don't understand what you mean by "about the sense of things in the world". It seems to me that this is just a convoluted, ambiguous phrase, meant to avoid the issue of what concepts which do not refer to anything in the world, are actually doing. This would include concepts like mathematical concepts. Surely mathematical concepts cannot be classified as metaphorical.

Words need boundaries. Words without boundaries are usually words without meaning. If everything is immaterial, the designation "immaterial" has no weight. — flannel jesus

In a language of abstract concepts, there are still boundaries, Such as between chair and non-chair, material and immaterial.

As with Derrida's "différance", the meaning of "material" arises from its relationship with "immaterial".