Maybe it’s relevant for indirect realists and dualists of all types, no doubt, but my relevant concern is why they’re begging the question, why they proliferate unobservables into a menagerie of ineffable terms and concepts, and why they’d eschew the 3rd-person perspective in favor of one that cannot even see his own ears, let alone what is occurring in the skull. — NOS4A2

It’s not begging the question to accept the reality of a first-person perspective with phenomenal character; it’s the foundation upon which the dispute between naive and indirect realism rests.

Their argument is over whether or not distal objects are constituents of this first-person phenomenal character.

But given that experience is an act involving a practical relationship between oneself and the rest of the world (and never a space located in the body with area and volume), it follows that objects are often participants of that act. — NOS4A2

The relevant concern is the phenomenal character of conscious experience. Everyone agrees that veridical perception involves the body responding to and interacting with objects in the wider environment. You're equivocating.

I don't understand your question.

It is simply the case that I'm acquainted with the phenomenal character of my experience, and that this phenomenal character is some sort of mental phenomena, whatever mental phenomena turn out to be (e.g. property dualism or eliminative materialism).

Given that conscious experience doesn't "literally extend beyond the subject's head, to encompass what the experience is of", the naïve realist's claim that distal objects and their properties are literal, non-representational constituents of conscious experience is false, and so the indirect realist account above is true.

Try reading more of the article.

Russell thus characterizes acquaintance as a relation of direct awareness, a relation in which, as Russell and some others have put it, something is “presented” or simply “given” to the subject.

...

Acquaintance with something does not consist in forming any judgment or thought about it, or in having any concept or representation of it.

...

We have already seen that for Russell acquaintance is nonjudgmental or nonpropositional; to be acquainted with something is to be aware of it in a way that does not essentially involve being aware that it is so-and-so. Russell seems to be extending this to knowledge by acquaintance: it is knowledge of something, and logically independent of knowledge that something is so-and-so.

I am simply, irreducibly, aware of my pain. I don't know what my pain is or what causes it; it's just there in awareness.

Maybe read up on the linked article on acquaintance. I'll start you off with this quote:

I say that I am acquainted with an object when I have a direct cognitive relation to that object, i.e., when I am directly aware of the object itself. When I speak of a cognitive relation here, I do not mean the sort of relation which constitutes judgment, but the sort which constitutes presentation. (Russell 1910/11: 108)

So which is it? — NOS4A2

We don't know; the hard problem of consciousness hasn't been resolved. All I know is that I am acquainted with pain and that I can't describe this pain in any simpler terms; pain is just pain.

Is a quale a property of experience or of mental objects? — NOS4A2

Qualia:

(1) Qualia as phenomenal character...
(2) Qualia as properties of sense data...
(3) Qualia as intrinsic non-representational properties...
(4) Qualia as intrinsic, nonphysical, ineffable properties...

If you are you ought be able to describe a property or two of each. — NOS4A2

This doesn't follow. It is properties with which I am acquainted. You're asking for a property of a property.

I'll quote from the SEP article on Acquaintance:

Most philosophers wedded to some notion of acquaintance end up rejecting the idea that we have acquaintance even with bread-box sized objects, immediately before us, under ideal conditions of perception. The test to determine with what we are acquainted is often reminiscent of the method Descartes recommended for finding secure foundations of knowledge—the method of doubt (see Russell 1912: 74; Price 1932: 3). If you are considering whether you are acquainted with something, ask yourself whether you can conceive of being in this very state when the putative object does not exist. If you can, you should reject the suggestion that you are directly acquainted with the item in question. Based on possibilities of error about physical objects from illusion, hallucination and dreams, it seemed to most that we could rule out acquaintance with physical objects, future events, other minds, and facts that involve any of these as constituents. Consider, for example, physical objects. It seems that the evidence that my experiences give me right now for supposing that there is a computer before me is perfectly consistent with the hypothesis that I am now having a vivid dream or a vivid hallucination. If this is right, then the experiential evidence I possess cannot be the computer or any of its constituents. Neither the computer, nor any of its constituents, need be present in that vivid dream or hallucination. Even when our evidence for the presence of physical objects seems as good as we can get, then, we are not acquainted with physical objects or their constituents. (However, some have recently defended the view that we can be acquainted with physical objects in perception. See, for example, Johnston 2004.) Traditionally, acquaintance theorists have taken the most promising candidates for entities with which we can be acquainted to be conscious states of mind (e.g., an experience of pain, a sensation of red) and their properties (e.g., painfulness, redness). Russell and many other acquaintance theorists also take themselves to be acquainted with facts, i.e., with something’s having some property—at least mental facts (e.g., my being in pain, my desiring food, my experiencing red).

I’m just saying that you’re not acquainted with mental phenomena. We’re so unacquainted with mental phenomena that we cannot even describe one. If we were acquainted with mental phenomena this whole issue wouldn’t be such a struggle. — NOS4A2

I'm definitely acquainted with the pain I feel when I stub my toe, and the cold I feel when it's winter, and the blue I see when I look to the sky.

You treat them and speak about them like they are objects. — NOS4A2

I don't know what you mean by "object".

I'm only saying that in perception I am acquainted with mental phenomena.

You can name them. — NOS4A2

Yes. They're primitives, so can't be explained further. I am simply acquainted with them.

Yet we are unable to describe a single quale — NOS4A2

Pain, cold, red, sour, etc.

A simple summation:

P1. We are acquainted with the phenomenal character of experience.
P2. According to the naive realist, the phenomenal character of experience is constituted of distal objects and their properties.
C1. Therefore, according to the naive realist, we are acquainted with distal objects and their properties.
P3. According to the indirect realist, the phenomenal character of experience is constituted of mental phenomena.
C2. Therefore, according to the indirect realist, we are acquainted with mental phenomena.

Note that the term "mental phenomena" is impartial to property dualism and eliminative materialism.

Note also the technical term "acquainted", as described here.

And as explained above, for the phenomenal character of experience to be constituted of distal objects and their properties it requires that perceptual experiences "literally extend beyond the subject's head, to encompass what the experience is of".

Visual experience occurs when the visual cortex is active. We don't need to talk about what a cow is doing to talk about what the brain is doing.

Naïve Realism, Seeing Stars, and Perceiving the Past provides a good account of what "constituent" means for naive realism:

[N]aïve realists have to accept what might be called a radically non-Galilean ontology – i.e. an ontology that, far from kicking the sensible qualities upstairs, into our minds, rather locates those sensible qualities within the external world we see and sense. As Campbell (2010, p. 206) puts it, naïve realism ‘depends on the idea that qualitative properties are in fact characteristics of the world we observe’, whereby this is because, according to naïve realism, ‘our experiences have the qualitative characters … they do in virtue of the fact that they are relations to those aspects of the world’.

Naïve realism is thus a radically externalistic view about the nature of perceptual experience. For it implies that our perceptual experiences, rather than being ‘narrow’ mental events which occur just inside the head, instead reach all the way out to the external things they are of and thereby ‘literately include the world’ (Martin, 1997, p. 84). As Logue (2009, p. 25) observes, on naïve realism, our perceptual experiences ‘literally extend beyond the subject's head, to encompass what the experience is of’.

It also provides a good account of indirect realism, avoiding to frame it in the misleading way that others have:

On the sense datum view, seeing an object, O, is a matter of having some visual experience, E, that has been caused by O in the appropriate way (whereby E's intrinsic nature can be characterised independently of O).

Such visual experiences have phenomenal character, and we are acquainted with this phenomenal character. This is all that is meant by "seeing sense-data/qualia/mental representations".

What do you think "constituent" means?

Then where is the mediation of our perception of visual objects by the perception of some other entities such as sense-data? — Luke

We feel pain – a mental phenomenon – and it is in feeling this pain that we feel the fire. We taste a sweet taste – a mental phenomenon – and it is in tasting this sweet taste that we taste the sugar. We see shapes and colours – mental phenomena – and it is in seeing these shapes and colours that we see the cow.

If you agree with this, then you are arguing for direct realism. If you want to argue for indirect realism, then you must hold the view that our visual perception of material object is mediated by the perception of some other entities, such as sense-data (or mental representations). — Luke

You misinterpret what "perceive mental phenomena" means. I feel pain, and pain is a mental phenomenon. The schizophrenic hears voices, and these voices are a mental phenomenon. I see colours, and colours are a mental phenomenon. This is all that is meant.

And this is where you're reading something into the grammar that just isn't there. I feel pain, and pain is a mental phenomenon. The schizophrenic hears voices, and these voices are a mental phenomenon. I see colours, and colours are a mental phenomenon.

This is all is that is meant by saying that we feel and hear and see mental phenomena.

This is precisely why, as I have repeated ad nauseam, that trying to frame the issue in such terms as "either I see distal objects or I see sense data" is a confusion and a red herring.

The only thing that matters is whether or not distal objects and their mind-independent properties are non-representational, more-than-causal, literal constituents of conscious experience. If they are then direct realism is true and if they're not then indirect realism is true.

The existence of something like a mental representation is what it means for our perception of distal objects to be mediated.

I addressed this before when I asked you to explain the difference between "seeing" a mental representation and perception "being" a mental representation. You were unable to do so. And that is precisely because there is no difference.

The natural numbers do not end, yet they have a successor in the ordinal numbers, namely . This is an established mathematical fact. — fishfry

And as I keep explaining, the issue with supertasks has nothing to do with mathematics. Using mathematics to try to prove that supertasks are possible is a fallacy.

See here.

It does follow. Something that exists in one location cannot be a constituent of something that exists in a different location.

Distal objects are not – and cannot be – constituents of something that occurs in the brain.

I addressed that here.

What would qualify as a constituent of experience? I'm drawing a blank. — frank

If property dualism is correct then qualia I suppose. Otherwise the constituents of experience just are whatever physical things mental phenomena are reducible to.

Distal objects do both, cause and become and/or 'act' as necessary elemental constituents of veridical experience. — creativesoul

Conscious experience occurs in the brain, distal objects exist outside the brain, therefore distal objects are not constituents of conscious experience.

As a regressive version of the argument, rather than me speeding up as I recite the numbers up to infinity let’s say that I slow down as I recite the numbers down from infinity.

At the 60 second mark I said “0”, at the 30 second mark I said “1”, at the 15 second mark I said “2”, at the 7.5 second mark I said “3”, etc.

Is it metaphysically possible for such a task to have been performed? No, because there is no first number that I could have started with.

That we can sum an infinite series with terms that match the described (and implied) time intervals is a red herring.

There is a far more fundamental, non-mathematical, logical impossibility with having counted down from infinity, and that very same fundamental, non-mathematical, logical impossibility applies with having counted up to infinity as well. You're being bewitched by maths if you think otherwise.

"The sequence of operations ends" means that "all operations in the sequence are performed". — noAxioms

The operations in the sequence occur one after the other, so all operations are performed only if some final operation is performed.

The logic of consecutive tasks is different to the logic of concurrent tasks. Your account equivocates.

If I never stop counting then … I never stop counting, and if I never stop counting then at no time have I ever counted every number.

That my dog is named "Bella" depends on me. That Bella exists and eats and sleeps does not depend on me.

That this period of time is named "60 seconds" depends on us. That 60 seconds pass does not depend on us.

You don't seem to understand how reference works.

Are you quoting naive realists, though? — Luke

Martin, Fish, and Allen are naive realists, I'm unsure if Nudds is or if he's just explaining naive realism, and the two SEP articles give overviews of the various positions without the authors commenting on their personal position.

Some more quotes from two naive realists:

Naïve realism is the view that the conscious character of experience in genuine cases of perception is constituted, at least in part, by non-representational perceptual relations between subjects and aspects of the mind-independent world. — French and Phillips 2020

[N]aïve realists hold that ... [t]he conscious visual experience you have of the oak has that very tree as a literal part. — French and Phillips 2023

I think "reciting natural numbers" is a red herring, because it's perfectly clear that there are only finitely many atoms in the observable universe, and that we can't physically count all the natural numbers. — fishfry

Then rather than recite the natural numbers I recite the digits 0 - 9, or the colours of the rainbow, on repeat ad infinitum.

It makes no sense to claim that my endless recitation can end, or that when it does end it doesn't end on one of the items being recited – let alone that it can end in finite time.

So I treat supertasks as a reductio ad absurdum against the premise that time is infinitely divisible.

How is that any different?

You can count the natural numbers by placing them into bijective correspondence with themselves. This is the standard meaning of counting in mathematics. — fishfry

This isn't the sense of "counting" I'm using. The sense I'm using is "the act of reciting numbers in ascending order". I say "1" then I say "2" then I say "3", etc.

Say (in some hypothetical world, say current math or future physics) that we have a "sequence of actions" as you say, occurring at times 1/2, 3/4, 7/8, ... seconds.

It's perfectly clear that 1 second can elapse. What on earth is the problem? — fishfry

P1. It takes me 30 seconds to recite the first natural number, 15 seconds to recite the second natural number, 7.5 seconds to recite the third natural number, and so on ad infinitum.

P2. 30 + 15 + 7.5 + ... = 60

C1. The sequence of operations¹ described in P1 ends at 60 seconds without ending on some final natural number.

But given that ad infinitum means "without end", claiming that the sequence of operations described in P1 ends is a contradiction, and claiming that it ends without ending on some final operation is a cop out, and even a contradiction. What else does "the sequence of operations ends" mean if not "the final operation in the sequence is performed"?

So C1 is a contradiction. Therefore, as a proof by contradiction:

C2. P1 or P2 is false.

C3. P2 is necessarily true.

C4. Therefore, P1 is necessarily false.

And note that C4 doesn't entail that it is metaphysically impossible to recite the natural numbers ad infinitum; it only entails that it is metaphysically impossible to reduce the time between each recitation ad infinitum.

_{¹ A happens then (after some non-zero time) B happens then (after some non-zero time) C happens, etc.}

I would invite you to read up on eternal inflation, a speculative cosmological theory that involves actual infinity. Yes it's speculative, but nobody is saying it's "metaphysically impossible" or "logically incoherent." — fishfry

Which has no bearing on what I'm arguing.

Here's a definition for you: "a supertask is a countably infinite sequence of operations that occur sequentially within a finite interval of time".

The key parts are "sequence of operations" and "occur sequentially".

As in, I do one thing, then I do another thing, then I do another thing, and so on ad infinitum. It is metaphysically impossible for this to end. If it ends then, by definition, it is not ad infinitum.

What's logically incoherent about infinite sets and transfinite ordinals? — fishfry

I'm not talking about infinite sets and transfinite ordinals. I'm talking about an infinite succession of acts. If you can't understand what supertasks actually are then this discussion can't continue.

I have not claimed otherwise. — fishfry

Those who argue that supertasks are possible claim otherwise, and it is them I am arguing against. You're the one who interjected.

Nor does it disprove their metaphysical possibility. We just don't know at present. — fishfry

If I write the natural numbers in ascending order, one after the other, then it is metaphysically impossible for this to complete (let alone complete in finite time). This has nothing to do with what's physically possible and everything to do with logical coherency.

I gave you a mathematical model that puts your unsupported claims into context. — fishfry

And it doesn't address the issue.

If I write the natural numbers in ascending order, one after the other, then this can never complete. To claim that it can complete if we just write them fast enough, but also that when it does complete it did not complete with me writing some final natural number, is just nonsense, and so supertasks are nonsense.

That we can sum an infinite series just does not prove supertasks. It is clearly a fallacy to apply an infinite series to an infinite succession of acts.

To clarify, when you say that, according to naive realism, perceptions and perceived distal objects have the same physical constituents, do you take this to mean that perceptions and the perceived distal objects are identical? — Luke

You'll have to ask naive realists for specifics of what they mean; I can only quote what they say, which is that the relation between conscious experience and distal objects is more than just causal and is non-representational, using the term "constituent", which means "being a part".

So, distal objects and their properties are literal component parts of conscious experience; in the same sense, perhaps, that the red paint is a literal component part of a painting.

I'm not the one advocating for supertasks, yet you keep arguing with me that they are impossible. — fishfry

No, I'm responding to you to explain that your reference to mathematical sets and mathematical limits does not address the issue with supertasks.

Metaphysically impossible? Repeating a claim ad infinitum is neither evidence nor proof. — fishfry

I've provided arguments, and examples such as Thomson's lamp that shows why. And again, your reference to mathematical sets and mathematical limits does not rebut this.