I do. You can prove just about ANYTHING like that. "Imagine we live in a world where <x is true>. This proves we live in a world where <x is true>.

As far as I can tell, this is a rather ungenerous way of reading hte passage, but one i understand.

It wasn't suggested that the thought proves the empirical. The point is that if we could show that disparate phenomenal experience can arise from identical brain states, then this would defeat physicalism as currently thought about. It seems to me reasonable that this is a live argument that will probably survive most attacks, given we cannot show one way or the other. As noted elsewhere, no two people have 1:1 Hardware to bear this out. Which is why it's a thought experiment, I would think.

But, i concede, it is not irrational to just say "yeah, well, so?" but its meaningful to me.
— flannel jesus

How so? I — Tom Storm

At risk of sounding like a dick, I did quite lengthily do this in the post you quoted.

While this is obviously nominally true, It cannot be the case that an open-ended "well something is likely prove it wrong, sometime, somewhere, for some reason" is a valid argument, or defeater. It is self-effacing speculation. — AmadeusD

(we will need to tease apart some things here, because you've quoted large parts of that explanation)

Who says it is open ended? — Tom Storm

but who knows? — Tom Storm

Oh my guy, come on now.

Open ended ignorance also seems possible. — Tom Storm

For sure. But my pressure, such as it was, was trying to get you to commit to this as it would require you to basically claim ignorance on everything.

Well, it is the case that science provides reliable but tentative models which are regularly the subject of revision, so there's a sense in which we never arrive at absolute truth. — Tom Storm

For sure, but again, would you commit to the above?

non-physical (apart from concepts). — Tom Storm

Seems like a plain contradiction to me ;)

Sure. — flannel jesus

Nice.

That's not how the thought experiment goes. — Michael

Not sure that's a reasonable response.

The point is that if we could show that disparate phenomenal experience can arise from identical brain states, then this would defeat physicalism as currently thought about. — flannel jesus

Yes, that's absolutely the case! And absolutely not how it looked like it was being presented to me.

IF we lived in a world where Alice and Bob had the same brain states and processes, but were experiecing different things, THEN some aspect of experience is outside of physical brain states / processes. Sure.

We don't live in a world where we have proved the first part of that IF, so we cannot safely conclude the consequent is true.

The claim is that if it's conceivable that Mark and Alice have no relevant physical differences and yet see different colours despite looking at the same object then colours are non-physical.

And just for fun let's carry on from this and assume that the box in question reflects light with a wavelength of 700nm. If we show the above image to Mark and Alice then this is what they will see:




Both Mark and Alice will agree that the left hand side of the image shows the colour of the box as seen in real life (named "gred" in their language), although Alice will disagree with the right hand side being labelled "Alice's POV".

First of all, does it make sense to speak of shared sensations?

If the answer to that question is deemed to be negative, then inverted-qualia arguments cannot get off the ground, but in which case aren't necessary for refuting physicalism, for a negative answer to the former question would imply that the set of "Alice's sensations" is both disjoint from, and unrelated to, the set of "Bob's sensations", however they might be labelled. But then again physicalism cannot also get off the ground, since physical concepts are "shareable" by definition.

Recall Frege's semantic distinctions of sense (referring to a term's public usage), reference (referring to what if anything a term signifies) and ideas (referring to a term's private aesthetic meaning that varies from person to person). Then ask if a sensation is shareable in any of those above semantic aspects.

Obviously, Fregean ideas aren't shared by definition, so if by "sensations" we mean the Fregean ideas that each of us subjectively intuits about word meaning, then we can refer to our previous analysis and conclude that that the concept of inverted-qualia is nonsensical.

But if by "shared sensations" we are referring only to Fregean sense (which the word itself might suggest), then we are only referring to the shared public usage of the term "sensation". in which case "inverted qualia" could mean something like when two subjects react equally and oppositely to the same stimulus - a meaning which actually amounts to a physical definition of "inverted qualia", even if the concept says nothing about any underlying Fregean senses that will typically be assumed to exist regardless of the physical concept's silence on the matter. In fact, the very meaning of a "physical concept" might be interpreted to mean a concept that is by definition invariant to the Fregean ideas that individuals privately associate with the concept, in contrast to aesthetic concepts whose definitions are allowed to vary among language users in line with their unique Fregean ideas that they each associate with their shared terminology.

Lastly, the common-sense of naive realism and the classical psychology of perception might lead us to consider "sensations" as lacking any Fregean referents. Indeed, we tend to speak of an object as "looking red to an individual" but not as being red per-se. However, the later Wittgenstein remarked that different types of sensation vary as to the degree that the subject of the sensation attributes the sensation to himself versus the object of his perception. In Wittgenstein's example of a green stinging nettle, he points out that we will tend to refer to the nettle as possessing "green leaf patches" but not as possessing "painful leaf patches", and seemed to imply that the degree to which a sensation-type is attributed to the object of perception was determined by the Fregean sense of the sensation type.

First of all, does it make sense to speak of shared sensations? — sime

Possibly shared type, but not shared token.

Also I don't think language is at all relevant and is in fact a red herring. Presumably deaf, illiterate mutes who aren't blind can see colours.

It's possible that the colour that one deaf, illiterate mute sees some object to be isn't the colour that some other deaf, illiterate mute sees the object to be.

With respect to physicalism, the question is whether or not this difference in colour perception requires differences in biology, and with respect to naive realism, the question is whether or not one of them is seeing the "correct" colour (in the sense that that colour is a mind-independent property of the object).

If the answer to that question is deemed to be negative, then inverted-qualia arguments cannot get off the ground — sime

Huh? Why? Inverted qualia arguments are specifically about different S experiencing different things. The degree of difference is what seems to defeat certain theories.

For sure. But my pressure, such as it was, was trying to get you to commit to this as it would require you to basically claim ignorance on everything. — AmadeusD

I do claim ignorance of many subjects - origin of the universe, idealism, gods, consciousness - 'I don't know' seems reasonable to me. Pretty sure no one on this site knows either.

But this;

Who says it is open ended?
— Tom Storm

but who knows?
— Tom Storm

Oh my guy, come on now. — AmadeusD

-referred to two different ideas, so shoving them together seems unfair.

Back to my question, however.

Is your position not a case of a fallacy from ignorance? It may not be, but it seems so. Are you not essentially saying, 'I can't explain consciousness via physicalism, so it must be non-physical.'? Are you a dualist?

non-physical (apart from concepts).
— Tom Storm

Seems like a plain contradiction to me ;) — AmadeusD

Fair enough.

I do claim ignorance of many subjects - origin of the universe, idealism, gods, consciousness - 'I don't know' seems reasonable to me. Pretty sure no one on this site knows either. — Tom Storm

This is equivocal, though. Is it hte case that you don't know anything, or that you don\t know some things?

Who saysit is open ended? It might seem that way to you now, but who knows? — Tom Storm

referred to two different ideas, — Tom Storm

Oh, no you don't. Hehe.

Is your position not a case of a fallacy from ignorance? — Tom Storm

It's not really a case of anything. Intuitively, like 90% of people, I feel as if there are non-physical properties to my experience (and the world). I have never seen an adequate explanation of how many things are physical. I have no reason to commit to either, but I have plenty of reason to lean against physicalism, as it is. Its mild. Possibly insignificant.

It's not really a case of anything. Intuitively, like 90% of people, I feel as if there are non-physical properties to my experience (and the world). I have never seen an adequate explanation of how many things are physical. I have no reason to commit to either, but I have plenty of reason to lean against physicalism, as it is. Its mild. Possibly insignificant. — AmadeusD

Ok. That's reasonable.

Who saysit is open ended? It might seem that way to you now, but who knows?
— Tom Storm

referred to two different ideas,
— Tom Storm

Oh, no you don't. Hehe. — AmadeusD

Oops, you're right. I misread my own comments. Apologies. But can't I say that something might seem open ended now but who knows, in time it might not be?

Huh? Why? Inverted qualia arguments are specifically about different S experiencing different things. The degree of difference is what seems to defeat certain theories. — AmadeusD

Fregean ideas are necessarily perspectival, whereas the public meaning of Fregean sense is a-perspectival. So if by "qualia" you mean to refer to your first-person perspective constituted by your Fregean ideas, then what criteria of comparison to you propose to use to relate your lived and actual qualia with what you abstractly conceive and hypothesize to be my experiences? How could scientific analysis which is deliberately restricted to propositions stated only up to the third person, be of any help here?

On the other hand if by "qualia" you are in some sense referring to both of our experiences, then I presume you are no longer referring either to your actual first-personal experiences or to mine, but to some abstract concept. Which is the starting point of any behavioural, functional or computational third-personal analysis of "shared sensations" "sensation similarity" and so on, whether in type or in token.

Also I don't think language is at all relevant and is in fact a red herring. Presumably deaf, illiterate mutes who aren't blind can see colours. — Michael

Semantics is relevant, due to the aforementioned ambiguity as to what is being referred to when speaking of qualia. In these sorts of discussions, it is often implicitly assumed by participants that "qualia" is meant in some Fregean sense. Which does indeed permit the sort of abstract functional and behavioural analysis that you propose in terms of type-token distinctions and similarity criteria, but which also forgets the reason why "qualia" were included in philosophical parlance in first-place - as a means of bridging the subjective private understanding and use of language in the first person, with the use of physical concepts that speak only in terms of abstract definitions stated in the third-person.

With respect to physicalism, the question is whether or not this difference in colour perception requires differences in biology, and with respect to naive realism, the question is whether or not one of them is seeing the "correct" colour (in the sense that that colour is a mind-independent property of the object). — Michael

Yes, I am in agreement there, although I would say that the question you mention is with regards to the physical analysis of perception, rather than a philosophical analysis of perception which less constrained than physical analysis, since the latter analysis is free to define concepts in relation to Fregean Ideas, which isn't possible in an aperspectival physical analysis.

IMO, when eliminative materialists speak of "consciousness not existing", I interpret them to mean (whether they agree with my interpretation or not), that physical analysis is by definition restricted to the analysis of cognition and perception in terms of Frege's notions of sense and reference which constitute the meaning of "objectivity", but which does not include the meaning of "subjectivity" that refers to the unshareable Fregean ideas that modern philosophers often refer to as "qualia".

So positing an "inversion" of color qualia may not actually establish a difference in phenomenal experience - it may just be describing a difference in linguistic labeling habits. In the end, it may not even make sense to talk about "experiencing the qualia of red" as if there is some objective, mind-independent property that fixes what "red" refers to. Rather, we may just be experiencing the qualia of what is agreed upon or linguistically coded to be "red" within a particular cultural/linguistic framework. The very notion of inverting an experience of "redness" might be incoherent without that shared linguistic coordination.
For example, instead of the color wheel being inverted for Alice, the color wheel labels are. So Alice and Mark both experience the same qualia of "green", but Alice has a different label for it, so when they look at "green", Mark says that's green, Alice says that's blue, and yet they both see the same color and are having the same qualia experience. Anyway, not sure where to go with that, I just wanted to show that our experience of color is inherently intertwined with language and it should somehow be a part of the argument or at least mentioned. — Matripsa

After reading this thread I come to the conclusion that we do the same thing with the words "physical" and "non-physical". Those are just two different ways of talking about experience, reflecting different cultural/linguistic frameworks. Each is itself incoherent if situated within the other's linguistic coordination.

The problem with the op though is the premise you use to make your conclusion. You state that Alice and Mark "both experience the same qualia of 'green'". But this is not a true premise, Alice and Mark are different people, with different bodies, different memories and different experiences. Therefore it is impossible that they could both experience the very same quale. You might say they experience similar qualia, but never do they ever experience the same quale.

I think it is very important to respect this difference when talking about qualia, and recognize that two different people might share the same type of qualia, but they do not share the same qualia. And this is a very significant feature of language to understand. Sometimes we talk about things, and this speech can be described as numerous people talking about the very same thing, and other times we talk about types, and this speech can be described as numerous different things being classified as of the same type.

So if we talk about qualia, as if they are things which people are experiencing, and we say that there is red qualia, and green qualia, these are different types of qualia. But if we want to talk about one particular quale, an individual's experience of green, in a particular spatial-temporal context, we need to respect the fact that no one, not even the person experiencing this particular quale, would ever experience the very same quale, in a different spatial-temporal context.

The thing is that we have no access to physical things beyond our physiological boundaries. Physical things are themselves only latent in images of experiences. We cannot directly access the physical things beyond our minds, and our physical theories or even metaphysics are occasionally even thrown out for new ones.

So I think its relevant to question whether the invertibility of qualia relative to physical theories is actually a property of the physical things themselves or just a consequence of the way we process information about the world.

I am basically skeptical that our ability to imagine inverted qualia is anything more than my general ability to imagine different objects as having different colors, which would have an information processing origin rather than being inherently about metaphysics. I don't think there is much to reason to consider the difference between physical and non-physical (concepts beyond the) ways we process information. Hence why a p-zombie would have qualia concepts.

Edited: brackets

There are objective facts about colour. They are constructed, linguistically, but that to which they refer is objectively xxxHz or some such designation which is independent of experience or observation (it is hte same observation, however it is noted by the S observing it - the langauge is not important to this element). — AmadeusD

Thank you for taking the time to respond! I agree with your point, there are objective facts, however for the sake of the argument I was just elaborating on the inverted qualia argument, which does not argue for a physical possibility but rather a logical one.

I guess I lean towards qualia being the union of the physical and the non-physical. Qualia unifies the physical senses with the reflective subject. Qualia is the experience of something coming to be, the experience of becoming, while it is the experience of something that already is, at the same time, in a subject, like Mark. Like Alice — Fire Ologist

Thank you so much for taking the time to respond! You have a very interesting and refreshing view of qualia that I really appreciate. Your response reminds me of something I read by Karl Jaspers where he said "At the summits the activity is the inner action by which I become; myself; it is the revelation of Being; it is the activity of being oneself which yet simultaneously experiences itself as the passivity of being-given-to-oneself". Thank you again for your wonderful insights!

I can't quite grasp where the relevance is, or answer is, to my comment. Probably me. Sorry.

But can't I say that something might seem open ended now but who knows, in time it might not be? — Tom Storm

Yes, I think you can. I suppose this goes to whether or not that is a reason now for anything to be the case mentally.

First of all, does it make sense to speak of shared sensations? — sime

In a word — no. The word "red" and the meaning "stop" are reliably connected with the top light of the traffic signal. This is what we need to agree on and can agree on even if some of us are colour-blind.

But philosophers talk of sensations, formerly of impressions, currently of qualia, as internal subjective and radically private. Cue Wittgenstein's private language argument.

The only way to describe the sensation of the top traffic light that we have agreed to call "red" is to associate it analogically with other sensations - loud, angry, hot, that sort of thing. And this too becomes an agreed set of associations such that one cannot oneself know if they are personal to one's actual sensation or learned socially.

In the end, if we propose a possible sensation that is radically private (and all sensations are such), we cannot say anything about them at all. Certainly one can propose that my sensation of the top light is "the same" as your sensation of the bottom light, and vice versa, but this inversion can never be detected, by definition of the term 'sensation', and so such talk is meaningless.