My understanding of truth is that it is defined by the schema "snow is white" is true IFF snow is white, where "truth" is the correspondence between propositions in language and equations in mathematics and what is the case in the world. — RussellA

Is this meant to be Tarski's view? Surely he didn't talk about what was the case in the world -- only about the correct relations between language and metalanguage. If one language has to be "about the world," then we wouldn't have any logical or mathematical truths at all, or at least that seems to be the necessary consequence. I don't think Tarski intended this. Unless I'm mistaken, he included these kinds of truths in his schema.

This is a great description of what mental imaging is like, and accords completely with my own experience. But then what do you mean when you say:

A "mental image" couldn't even resemble visible objects such as cats or images — jkop

What it's like to see the cat is a feeling, not an image. — jkop

Doesn't your description contradict these statements?

I appreciate your taking the time to lay all this out for me. Could I ask you to take this to a simpler level, and describe to me what you think happens when I imagine a purple cow? I'm still concerned about the hard problem, understood as the emergence of subjectivity (or the illusion of subjectivity, if you prefer) from chemical/neuronal activity,

I understand. Do you think there are mathematical truths that are independent of what is the case in the world? Plain old theorems, in other words?

OK, but you can see that even this weakened version represents an entirely different order of explanation than:

1. Real life effectiveness

2. Fulfills emotional desires

3. Fulfills a power structure

By referring to "accurate representation," you've introduced an epistemologically normative factor that is nowhere implied in the first three factors.

I find all this somewhat plausible in the case of images that arise from perception of the world, and are meant to "stand for" or "picture" or "represent" something out there. Quite possibly the "out there / in here" duality is either mistaken or badly conceived. But . . . I don't see how it applies to my purple cow, or any other of the myriad ways consciousness operates without any perceptual stimulus. We agree that my imagining the cow is no illusion. How is this still a question of dualism vs. monism? I'm not claiming that the cow represents anything in the (dualistically conceived) world; in fact, the choice of "purple cow" is meant to preclude any such representation.

You'd written this:

Are mathematical truths necessary truths
Following the schema "snow is white" is true IFF snow is white as a definition of "truth", then "d=0.5∗g∗t2" is true IFF d=0.5∗g∗ — RussellA

So I assumed you regarded d=0.5∗g∗t2 as a mathematical truth.

What do you mean that the equation d=0.5∗g∗t2 has no meaning? — RussellA

Without some interpretation, some assigning of the symbols, it says nothing. I can vouch for this personally, as I have no idea what d, g, and t refer to in this equation! If you simply placed it in front of me, uninterpreted, and asked me what it meant, I could only shrug.

But if none of that is so, and what I was calling "subjectivity" is in fact a dualistic illusion, we still need to know how this comes about, and why.
— J
But that is what I've been saying - that seeing this as a dualist illusion IS the problem. Abandon dualism and introduce the idea of monism and see if that helps you solve the problem. — Harry Hindu

We agree that subjectivity could be a dualist illusion. (I don't think it is, but I'm happy to assume it for purposes of argument.) But if it is, we still need to know why. You say, rather cavalierly, "Abandon dualism." OK, I imagine a purple cow and I follow this up by saying to myself, "This experience of me-and-purple-cow-image is illusory. There is no separation." But this doesn't make the purple cow go away, or change into something else. I'm sure you don't believe this would happen either, but what do you believe? What changes, for you, in this sort of experience when you introduce the idea of monism? Is it that experience, as presented, becomes a sort of brute fact, about which it's no longer possible to ask questions? This isn't meant to be snarky, I'm genuinely interested.

A "mental image" couldn't even resemble visible objects such as cats or images — jkop

For me, a mental image strongly resembles a visible object. So I can only conclude that you're already analyzing "mental image" reductively to refer to whatever physical substrates it may supervene upon. I think that begs the question.

What it's like to see the cat is a feeling, not an image. — jkop

Again, I have to say, Not for me. We all know that "what it's like," despite having become the go-to term for subjective experience, is quite imprecise. Maybe that's a good thing. In my case, the "what it's like" is a combination of an apparent image, often a series of memories associated with the image, probably some future projections about the image, and, sometimes, a feeling about what I'm imaging.

It sounds like where we differ is that you want to eliminate the idea of a mental image altogether. I think there are plausible and persuasive reasons for doing this in the case of perceptions. But not for imagined or remembered images. If these experiences are not, in some ordinary-language way, mental images, then what are they? And how could they be explained away as being identical with their physical substrates?

Are you sure we should call something like d=0.5∗g∗t2 a mathematical truth? I thought it was only true on some interpretation; as it stands, it has no meaning.

Let me try to work up an example that is less controversially stipulative. — J

How about this?

For "object" in the "23 objects" question, let's say "chickens." We wish to divide 23 living chickens evenly among 3 people; we discover this can't be done. Here there's no question of how to define the object, or whether fractions can ride to the rescue. So: Is this division impossible for the same reason -- a distinctively mathematical one -- that the number 23 can't be divided evenly by 3? Or, if you don't accept "distinctively mathematical," how would you characterize it?

OK. So no one of your factors would be something like "This set of concepts more accurately reflects the ontological structure of the world"? You'd rely on pragmatic and/or personal-preference explanations for the chosen set of concepts?

Cool comparison, I hadn’t thought of it!

I don’t think I agree with your interpretation, though. You recall that Quine’s target was meaning-synonymy as a supposed criterion for analyticity. He readily acknowledges, at the start of the paper, that logical truths are excluded from his criticism. So we have to ask, is there a “parallel exclusion” in the case of explanations that include part math, part facts-about-the-world?

Taking the math part to be parallel with “analytic,” we want to know whether maths are logical truths (and thus both easily identifiable and unexceptionable, according to Quine), or whether they are more like meaning-synonymy statements. Frege may be helpful here; he also divided analytic statements into two groups. The first is Quine’s “logical truths”; the second is supposed to be reducible to logical truths on the basis of purely logical definitions. As Susan Haack points out (in her Philosophy of Logics), this would mean that “the truths of arithmetic are, in this sense, analytic.” (And Kant, of course, would disagree.)

Do Jha et al. take a roughly Fregean stance here, concerning the relation of math to analyticity? They don’t address this directly, to be sure, but I think they do. The reason lies in their reasons for rejecting distinctively mathematical explanations (DMEs) in the first place. Math, according to them, can’t play an explanatory role in scientific explanations because it can’t say anything about “the world,” due to its a priori nature. Now I know Kant though math could be both a priori and synthetic, but that has never struck me as plausible, and I think we should go with Frege. (And anyway, as @schopenhauer1 pointed out, the synthetic nature of math for Kant is transcendental. It operates as we structure experience, it’s not something we learn “in the world.”)

So if we attribute the Fregean stance to Jha et al., then they don’t say that “you cannot tease out any supposedly pure math part, roughly”. It’s precisely because you can do this that DMEs won’t work.

Still, it’s not a simple question, and I’m not sure I’m right.

Quine himself had very mixed feelings about whether the laws of logic were subject to revision. I think his final answer was yes, but it's a last resort, and they are very insulated, resistant to revision. — Srap Tasmaner

Just as an aside, I think Quine believed the laws of logic were true because we could supply clear definitions for all the operators and connectives. This is in Word and Object. In a subsequent work which I haven’t read, The Philosophy of Logic, he extends this to non-classical logics, according to Haack. She says that he accepts “a meaning-variance argument to the effect that the theorems of deviant and classical logics are, alike, true in virtue of the meaning of the (deviant or classical) connectives; which, in turn, seems to lead him to compromise his earlier insistence that fallibilism extends even to logic.” So it sounds like your "very insulated, resistant to revision" is spot on.

By clarifying their ambiguity we can get rid of some of the problems.

For example, in talk of the experience of seeing a cat, the word 'experience' or 'seeing' can refer to what is constitutive for having the experience: the feeling. But they can also refer to what the experience is about: the cat. — jkop

Good, this is helpful. I'm not using "experience" to refer to what the experience is about (the cat). But nor am I quite using it to refer to a "feeling." I suppose people can differ on this, but when I see a cat, I don't find myself feeling much of anything about it. What I do find is that I have, or seem to have, a mental picture. This is, for me, what is "constitutive of having the experience," as you say. But I don't think it matters too much whether the "inner" part is more like a feeling or more like a picture. The important difference, which you have disambiguated, is between "experience" understood as the object (putatively "out in the world") that is being sensed or thought of, and the subjective event of doing so.

So, what is left to explain is this: How does my brain create the feeling?, and I believe we know at least something about how feelings are evoked by hormone levels, neurons releasing dopamine etc. — jkop

But here, your reliance on "feeling" as the correct subjective description does make a difference. It allows you to talk about hormone levels, dopamine, etc., as possible causes of feelings. I'm sure they are. But the kind of "feeling" involved in having a mental image of a cat is surely not explainable by hormone levels. I know you're not saying that it is, only that we're not as ignorant about the whole process as I've been arguing. I'm not persuaded, though. Can you sketch even the beginning of an explanation of a mental image that involves feeling-type causes such as hormones or other chemical items? I think this would be even harder to do in the case of an imagined image -- one that I simply "think of" as opposed to being stimulated by a perceptual event.

The impossible request that we ought to explain how hormone levels etc create the illusion of a Cartesian theatre seems to be based on a fallacy of ambiguity. — jkop

Can you explain? I thought you disambiguated it nicely. Is this a different ambiguity?

I realize I've been using the term "privileged structure" without much explanation, as if everyone is familiar with Theodore Sider. Let me expand a little. Sider uses the "grue and bleen world" example (which you can read about here, p. 16) to refer to a situation that he believes needs explaining: If we encountered a people who used grue and bleen as their concepts, we'd be unable to fault them on any logical grounds. Nor would anything in the world contradict their choice of these concepts, as concepts -- there really are grue and bleen things, and we know how to say true and false things about them. They would of course prove completely unworkable in practice. But why? What makes our green-and-blue conceptual world better? Is it simply a pragmatic question? But that only pushes the question back a step, for now we have to ask, Why does it work better? Is that just lucky for us, or is there something about the world, and its structure, that green-and-blue reflects with more than mere accuracy? If so, that would be a privileged structure in Sider's sense, and the grue-and-bleen world would not.

So, on that understanding, how would you explain privileged structure? I can see how you can demonstrate the pragmatic success, but what's the next, explanatory step?

I did read the summary. Is this the passage you're referring to (concerning "privileged structure" or the like)?:

"Applicable knowledge is when a form I have created in my mind, fits reality. The simpler the properties in the distinctive knowledge, the simpler the applicable knowledge accrued. If the essential properties of sheep are curly fur and hooves, this would be indistinguishabl[e] from for example a goat."

I think I could add "the illusion of" in front of every reference to "subjectivity" and it wouldn't alter the problem. If I understand you, you believe that subjectivity only becomes a "problem" when it is labeled as subjective and claimed to be a mirror or a window or something that validly reflects an external reality. But if none of that is so, and what I was calling "subjectivity" is in fact a dualistic illusion, we still need to know how this comes about, and why.

I see what you're saying. Let me try to work up an example that is less controversially stipulative. As for the analytic/synthetic distinction, I'm not sure we really have to go there. Perhaps it won't do as a description of the difference between logic and facts-about-the-world, but wouldn't you agree that Jha et al. are pointing to something that can be talked about, and represents a genuine question? Or perhaps you wouldn't.

Yes, that all seems right to me. The question you were raising, though, was about particular "matches with reality" that, in addition to being logically consistent and uncontradicted by the facts (such as grue and bleen), also constitute an "identity" -- perhaps like natural kinds? I just think this needs further explanation; logic and noncontradiction alone won't get us to why some matches seem more natural or reality-mirroring than others ("privileged structure").

Ok, please explain to me why we can't talk about all this without using the word 'observer'? — jkop

I was hoping that, by working together on a version that didn't use subjective words, the reason would become clear. But OK, I'll be didactic: Descriptions of consciousness in physicalist terms presuppose the existence, as conscious states, of the phenomena they're meant to explain. (This excludes versions of physicalism that simply deny the existence of consciousness, but that's not your thesis, nor mine.)

Let's look at your original thesis again:

Moreover, conscious states such as visual experiences have a hierarchical structure in the sense that the experience is not solely a biological phenomenon. It is also causally constrained by the behavior of light, and influenced by the observer's psychology, sociology, language and culture. All of these can be described, but none of them is a complete description of the experience. However, the lack of a single complete description is hardly a problem. — jkop

We need a physicalist translation, or reduction, of "experience," for starters. In what sense is visual experience biological? Do we know how our brains create the illusion of the Cartesian theater that characterizes subjective experience? Not at all. You can say, "Someday we will," and I agree that's likely, but at the moment it's unsolved, and it's not a matter of lacking a description, as you put it. We lack any theory at all about how and why it happens.

Even more concerning, the use of "observer" postulates an "I", a subjective point of view. This, for me, is the really hard part of the hard problem. We can't just help ourselves to the term "observer," in trying to explain or describe consciousness. On the evidence, there's nothing in biology, psychology, sociology, language, or culture that even hints at an explanation for a first-person point of view. In fact, you'd expect the opposite -- these living systems are so beautifully and intricately evolved that they seem quite capable of doing their thing like zombies, or robots, with no "there" there. Why isn't that what happened, and what did happen? Again, we can't just say "And along came consciousness . . ." or "Then consciousness emerged as a property . . . " because these are just placemarkers for our inability to solve the hard problem (yet).

Whew. But I really think it's more useful to try it yourself, just as an experiment. Try taking the above quoted passage and rewriting it without any subject-based or experiential terms. I think you'll wind up with something that either doesn't talk about consciousness at all, or else merely defines it as physical, or assumes it to be physical, rather than explaining it.

So where are abstractions taken from? I suggest "the world" is a sensible answer, and one that explains the "mystery" rather well — unenlightened

It is indeed a sensible answer, but doesn't explain what appears to be the modally necessary character of the abstractions, and their role in explanation, if any. Have you read the target paper I cited? It might explain the problem better than I have.

I can see that you wouldn't like this approach on the grounds that it shoots your fox and spoils the fun of the chase. — unenlightened

My fox is quite healthy still, thank you! And anyway, I'm an animal rights activist and must urge you not to shoot at any foxes, real or metaphorical. :wink: (You can imagine how I grit my teeth whenever Ted Sider (and Plato) go on about "carving reality at the joints.")

These two responses show a similar approach to the problem, which I think is mistaken. We shouldn’t be conceiving of the “Distinctively Logical Explanation” question as a question about how to define terms, or about whether language can resolve the question. The DLE problem assumes a linguistic stipulation that is uncontroversial or at least agreed-upon, or at the very least accepted for the purposes of discussion. With this stipulation in place, we then go on to ask about the relation between logic-or-math-as-necessity and the alleged necessity of events in the world, such as the 23 objects that can’t be evenly divided, or the cat that can’t be here and in Paris too.

It is trivially true than any given definition of an “object” will determine what we can say about it, using math or anything else. The larger puzzle is this: How is it the case that, no matter what definition we use, we discover these regularities between math/logic and the world? Even the bizarre definitions of “cat,” once accepted, have unambiguous consequences in terms of regularities. Wayfarer calls this a case of the world “mysteriously agreeing with our abstractions,” but that begs the question. Is it the world that is doing this, or are our abstractions mysteriously agreeing with the world? Are there abstractions that “agree” better than others? This is the Phillips-head screwdriver problem. We can just accept the agreement as a brute fact, not mysterious at all, or we can claim a coherent evolutionary explanation, or we can continue to ask why. My only point here is that I don’t think we should look to language for a solution. Resolving a linguistic ambiguity won’t tell us whether math/logic is a genuine causal constraint on the world.

So mathematics models the world because the world exhibits regularities that can be mathematically described, not because the world is constrained by the mathematical framework. — Wayfarer

I think this is Jha et al.'s thesis, pretty much. It's the world's (causal) regularities that permit math to function as part of an explanation. A different world, if there could be such, would reveal different regularities, but the role of math would be unchanged.

Personally, I believe that irreconcilable differences between quantum physics and classical physics will be resolved with a proper explanation of consciousness. — Harry Hindu

I have the same hunch. Ever read The Emperor's New Mind by Roger Penrose?

I don't know what "appearance to a mind" means. It seems to imply that a mind can be independent from some appearance as if something appears to a homunculus in the brain. — Harry Hindu

I know, the right language is hard to find. What I think we want to describe is the subjective event that occurs when, say, I think of a purple cow. The image of the cow is rather like something that "appears to a mind" but if that seems too Cartesian-theater, no matter. We can perhaps find better language, but I hope the target concept is clear enough: First the cow isn't there (for me), and then it is, not as a pattern of neurons but as a cowish purply image. What has happened? That's the event we're concerned about, which I'm suggesting we could call a "phenomenon".

Any appearance in the mind is the result of some measurement in that the brain measures and interprets wavelengths of light and sound and these measurements are the means by which we interact with the world. — Harry Hindu

The problem here is that, in order to get from "brain measurements of wavelengths of light and sound" to "an appearance in the mind" and the idea that "we" interact with the world, we have to import some new concepts. Mind? We? Where did this subjectivity come from? Once again, the hard problem: How do we get from here to there? Why should there be anything like an appearance in the mind, if the brain seems ideally equipped to do the measuring on its own and respond accordingly?

To say that the alignment between screwdriver and screw is an opaque and brute fact is to have abandoned the search for an overarching explanatory structure. If there is an explanatory structure that preserves both, then that explanation must encompass both the mind that knows reality and reality itself. I don't see how one could arrive at an explanatory structure such as you desire without this overarching aitia. — Leontiskos

Yes, and in fairness, a good evolutionary explanation wants to respect these constraints. It wants to show us how both mind and the world evolved to reflect what you're calling the unum of being and truth. But as Nagel and others have pointed out, if the explanation is genuinely scientific, then it's going to have to account for consciousness (mind) before it can tackle any relation between mind and world. And of course a really thorough explanation would almost certainly dissolve this crude binary, "mind/world". Moreover, the "mind" of evolution may or may not turn out to be the same thing as whatever would be able to, for instance, participate in the Forms. In other words, we may not be able to get from "mind" understood as a singular psychological/biological phenomenon to the sort of mind that could have access to truth. Anyway, we're a long way off from any workable theories about all that.

My take is that the tremendous success of our efforts to understand the world, which has translated into the causal mastery embodied in techne, represents strong evidence that we do come equipped to know the world and that the world is intelligible. — Count Timothy von Icarus

I think we have to leave a pretty large area of "the world" open to hermeneutic interpretation rather than empirical/analytic inquiry, but as long as we do that, the world does seem intelligible, as you say. I suppose people will differ here -- for some, that's enough said; for others, me included, there's still the question of why? Maybe "it just is"? But isn't that super-convenient for us? Can some sort of evolutionary account get us to an explanation? Nagel's concerns enter here . . . plus, there remains the question of whether any of this entitles us to speak about necessity and impossibility.

I buy Gadamer's argument that it's quite impossible to make any inferences without begining with some biases. We can always question these biases later. — Count Timothy von Icarus

Me too. I've noticed that some philosophers want to use logical principles as a kind of bulwark against the dreaded hermeneutic circle, which they fear leads to logical nihilism, and relativism in general. Would Gadamer agree that the LNC is a bias? Need a new OP for that.

Yes, that's why the constraint of "whole and unbroken" matters. But that doesn't make Q2 a linguistic problem, since we've stipulated what an "object" will be in this question. We've solved that problem. But what about the problem posed by the question itself, now disambiguated? -- presumably you'd say "No, it can't be divided evenly" and so we want to know whether this is due to a mathematical fact or a fact about the world.

Oh, it left a big impression! He's an elegant, insightful writer. But I think he's wrong on every important point. This is too major a question to tuck into this OP, but I'd love it if you or someone else wanted to do an OP on Rortian pragmatism.

(Have you seen the discussion of Rorty by Richard J. Bernstein, in connection with Gadamer and Habermas, in his Philosophical Profiles? Bernstein's view is, approximately, the same as mine.)

I'm sorry, I wasn't clear. I didn't mean simply omit the terms! I meant rewrite the thesis but avoid using those terms. Give a description you believe is accurate but that doesn't have recourse to "observer" or "experience" .

Could you refer us to which post? And perhaps quote some key passages here, so we can respond? Thanks.

Math, like language, is a tool of logic with rules. If we use it with the idea that our abstraction is trying to match reality, and we are correct in matching our abstractions to reality, it works because that's how we perceive identities, and our identities are not being contradicted by reality — Philosophim

I see what you mean, but we can construct an infinite number of worlds with different abstract entities highlighted (see "grue and bleen", Sider, p. 16) and most of them won't "work" at all, if by "work" you mean "give us a useful conceptual basis for navigating the world." Yet there is nothing wrong, logically, with the way these abstractions are being matched to reality. So can you expand on what it is to "perceive an identity"? -- that seems crucial.

Pancomputationalism . . . would make cause (i.e. how past states determine future states) a sort of stepwise logical entailment. — Count Timothy von Icarus

Does the "pan" part of pancomputationalism provide a response to Jha et al.'s objection? That is, are the background assumptions which Jha et al. call "the very facts that make a purely mathematical result applicable" also generated computationally? I'm out of my depth here, but is there meant to be a beginning to this process of entailment -- some first premises?

Yeah, but remember Kant thought math was synthetic a priori. In other words, our minds are still structuring time and space and experience. The math wasn't "in the world", that would be violating his phenomenal/noumenal distinction — schopenhauer1

OK, I think that's right.

evolution does provide a certain flavor of answer whereby our brains could not but do otherwise. — schopenhauer1

It's appealing as an answer, no doubt. What troubles me about the evolutionary explanation is that the "arrow" seems to go from experience to thought. That is, our minds evolved as they did because of what we encountered in the world. This seems to make the LNC, e.g., contingent on the way the world is. But don't we want something much stricter than that, some way we can talk about necessity and impossibility? Can we arrive at what you're calling "a necessary understanding of the world"?

I'll bring in Nagel any post now! :smile:

acknowledging the various debates of Hume and Kant. — schopenhauer1

Yes, and thanks for the summary. Is it clear to you that either Hume or Kant has the better explanation here? Are Jha et al. Kantians? (Note, too, that Kant did not think math was analytic, like logic. He thought it gave us synthetic knowledge about the intuitive concept of "magnitude" -- that is, number per se. This makes me wonder if he would allow math an explanatory role, as in the above discussion.)

The problem isn't the lack of a complete description. Rather, it's how we can even talk about all this without importing (as you do) the term "observer".
— J

Ok, please explain to me why we can't talk about all this without using the word 'observer'? — jkop

Well, try revising your original description (beginning "Moreover, conscious states . . .") but leave out the terms "observer" and "experience." Let's look at the result and see what we think.

For example, a feeling of being drunk (its existence and why it exists the way it does) is uncontroversially explained by the effects that alcohol has on our cognitive functions. — jkop

Once again, "cognitive functions" is imported into the description as if we knew what it meant, in strictly physical terms. Try revising this description in the same way as suggested above.

Now I don't think we're anywhere near a synthesis of consciousness from unconscious compounds, but if seems fairly clear that consciousness is a biological phenomenon. — jkop

Fairly likely, at least.

Moreover, conscious states such as visual experiences have a hierarchical structure in the sense that the experience is not solely a biological phenomenon. It is also causally constrained by the behavior of light, and influenced by the observer's psychology, sociology, language and culture. All of these can be described, but none of them is a complete description of the experience. However, the lack of a single complete description is hardly a problem. — jkop

The problem isn't the lack of a complete description. Rather, it's how we can even talk about all this without importing (as you do) the term "observer". What possible physicalist justification can there be for this, much less an explanation? "Experience" is another imported word. Sure, we can describe a subjective experience, but how do we explain its existence, or why it exists in the way it does and not in another? That's the hard problem.

In this sense, consciousness is the presence of colors, sounds, smells, and feelings and the thoughts that categorize these sensations into logical ideas the same way a soccer game is the presence of 22 people on a field following rules. — Harry Hindu

Not so sure about "logical ideas" (maybe just "ideas"?) but otherwise I agree.

How do we get from that to consciousness being the interaction of neurons? Is it two separate phenomenon, or the same phenomenon being described from two different perspectives? — Harry Hindu

At this point we need to make sure it's not just a dispute over terms. What do we want "phenomenon" to designate? I vote for something like "appearance to a mind," so that the 22 people and the soccer game are two different phenomena. On that understanding, I want to say that neurons and consciousness are also two different phenomena, appearing from two different perspectives. But notice that it doesn't really matter how we understand "phenomenon" here. We could go the other way and stipulate that "phenomenon" designates a single event in time, in which case the soccer game and consciousness are now redescriptions of "the same phenomenon." Either way, we're left with the hard problem. I know many people want to do some arm-waving here and say, "Well, it's two different descriptions, what more do you need to know?" but surely the answer is, "A lot. Why are these descriptions as they are? What allows the passage from one description to another? Are we right in believing that the mental-level description is grounded in, but not caused by, the physical-level description? Does the physical-level description have a "translation" into Mentalese? When we encounter something as extraordinary as subjective experience, what else do we need to say about it to fill out the experience? Yes, consciousness is, in a sense, "only" a description of how things look to a subject, but don't we feel it's a lot more than that too -- somehow constitutive of identity?" etc. etc.

Interesting paper, thanks, though I lack the background for some of the science. Still, I think I get the point. But I don't understand how anything Anderson says refutes a potentially physicalist understanding of the world. He refutes reductionism very well, but my attempt to invent a "best we can do now" version of physicalism was not meant to affirm reductionism, quite the contrary. Maybe the question I should be asking is, What is there in Anderson's paper that introduces a non-physical level of construction, or implies that there's anything "beyond the physical"?

"Sensing" is doing the work of two meanings that shouldn't be confused here.

1) Sensing- akin to "responding in a behavioral kind of way"
2) Sensing- akin to "feeling something".

Clearly we want to know how 1 and 2 are the same, or how 1 leads to 2, etc — schopenhauer1

Right. "The thermostat is sensitive to the temperature" vs. "I feel warm [sensitive to the temperature]". Either is good English, but the philosophical difference is considerable.

I suggest this, though: Hopefully, only a behaviorist believes that 1 and 2 are literally the same. Perhaps what we want to know is, first, How does "feeling something" (sense 2) lead to a physical response (the so-called problem of mental causation)? and, second, Is there a physical substrate in the brain upon which "feeling something" (sense 2) supervenes, such that the feeling is not caused by that substrate? I believe that separating grounding from causation is extremely important here, because otherwise we risk getting pushed into an explanatory situation in which a physical process causes a mysterious and elusive mental effect, despite the best efforts of science to discover it. There's no need for this if we think in terms of supervenience instead.