So, for me, I don’t think this kind of reasoning is sufficiently elaborated on by saying “follow your intuition”--as, for me, that sounds like all levels would contain intuitions. — Bob Ross

This is fair I think.

They would not be able to operate, which is means no knowledge of the world whatsoever. — Bob Ross

Yes, agreed. I guess I do kind of agree with you on this point in the way you're putting it now, I think I was just thinking about the notion of "objectively best way to get knowledge" in a different way beforehand which I would be more skeptical of.

Rather, I mean that when explaining a set of data (about reality), do not extraneously posit entities (as it is superfluous and corresponds to nothing confirmable in reality). — Bob Ross

I still think I disagree profoundly on this one. If it is not about picking the correct explanation then I don't see an obligation to pick the more pasimonious explanation that would be independent of some further contextual details.

I do not merely mean intuitions but, rather, all forms of evidence (which includes intuitions). — Bob Ross

Yes, fair. I don't think this changes my interpretation of what was said however since I was explicitly thinking that we accept or reject evidence in a way which has recourse to intuition so I was actively envisioning both of these being subsumed under "follow your intuition".

It is an inevitable rule that we must follow if we want to know the world as best as we can. — Bob Ross

It seems to me most likely the only coherent way of approaching knowledge but if it doesn't necessarily give me knowledge I don't see it as objective. If someone has particularly bad intuitions then maybe a different rule would give them knowledge better.

and it isn’t that evidence is purely ‘intuitional’ — Bob Ross

I think my point thought evidence being intuitional is that if you look at some evidence and accept it then ask yourself why you accept it, it leads to intuitions eventually. You may have a reason why you think that evidence is good, but then ask yourself why that reason is good, and then the reason for that reason and so on... I feel like it would just end up at intuitions and so in a sense, everything we do here is on some level driven by intuition.

Like I said previously, strictly going against one’s intuitions will almost certainly lead to accepting that which is false. — Bob Ross

But my point is that it depends on the context so I can't say it is objective unless I rule out that alternative contexts (e.g. having awful intuitions) are possible, which I cannot do. There will be contexts when going by someones intuitions will be counterproductive too.

Because it claims to know extraneous information about reality, since it deploys extraneous explanatory entities to explain the same data about reality. It is purely imaginative and non-factual “knowledge”. — Bob Ross

I think the notion of parsimony I'm more used to is about what seems most parsimonious choice between some options so it is in some sense a subjective thing and not really about factual knowledge. The way you have described it just now seems to be more or less equivalent to "just pick the correct explanation" which is a bit redundant since you don't know what that is. Who knows maybe what you thought was the most parsimonious explanation may turn out insufficient under further evidence which would be an example if the rule not working out.

I don’t think this works, as you are saying that if it strikes you as the case that the counter-evidence (which would change your mind) was true, then you should do the opposite and thusly not change your mind. I don’t see how one would be receptive to evidence if they always have to negate their intuitive reaction to the situation, as they would be obligated to never accept counter-evidence that they would normally accept. — Bob Ross

I was assuming a separation between one's initial intuitions and the process fo evaluating evidence but this is a good point that they could converge in the sense that accepting or denying evidence would rely on intuition.

However, at the same time this conception seems to be viciously circular in a way that almost defeats the purpose of framing the question the way you did when it could have been done simpler - just follow your intuition (because I am using intuition to accept or reject evidence also - or perhaps you could frame it as "follow your intuition and then when you get an intuition that this last intuition was wrong, follow the new intuition"). I don't see how this could be an objective rule though as your intuitions could be faulty and never lead you to truth, never lead you to accept the correct evidence or interpret it in the correct way. It presupposes something about our intuitions which may not be objective; in fact, in a scenario where we have no reason to think our intuitions are very good, including intuitions about evidence, going against intuitions may still be as effective a way to find knowledge.

I agree that it makes very little sense to not follow your intuitions in the way i described above in the bold part, and it makes little sense to something like take up a belief which you believe to be wrong. At the same time, just because this is the only really coherent way to go about looking for knowledge, doesn't mean it objectively gives us knowledge.

If they both explain the same data, then it is extraneous to accept the more complicated theory: it is just superfluous and, thusly, there is no legitimate reason to accept it — Bob Ross

But so what? Some people may have a preference for superfluous explanations. Why does that matter if a superfluous one is just as good at predicting what we want to predict as the non-superfluous one?

but I do think that it is a factor for ‘knowing the world’ better, if that makes any sense. — Bob Ross

Yes, I think almost everyone wants their beliefs to be logically consistent and not to actively select inconsistent models or views of the world.

I actually think I more or less agree with a fair amount you talk about in the last two posts you make about information and the "arms-length" separation of observer, though maybe I would describe it in different language. I definitely do have a different perspective but there is definitely stuff I agree on, I think.




I thonk you are begging the question by presuming dualism, presuming some separation that needs to be explained. My belief is dualism is false and so there is nothing to be explained but at the same time, there's nothing stopping me from having concepts of both the mental, the physical, or various other things.

Are you saying that taking what doesn’t strike you to be the case as the case would be equally legitimate as doing the contrary?

Yes, because at the end of the day, aslong as you are receptive to evidence and change your views based on that then it should lead to the same result.

Of course, what one thinks is necessary could be different than what another thinks, but that is not of concern for this principle itself. — Bob Ross

Yes, but why should one have to use parsimony if a non-parsimonious explanation is just as good? If the non-parsimonious one gets the job done, is there really a requirement to use a more parsimonious one?

True. But if you believe something with higher confidence than something else, then why would it ever make sense to, when in conflict, take the less confident belief as true over the more confident one? This seems irrational to me and clearly not a good way of ‘knowing the world’. — Bob Ross

Yes, true it subjectively doesn't make sense to take the less confident belief to be true but then if you are mistaken about your high confidence beliefs then this practise will systematically give people wrong answers.

I will grant that it doesn't actually make sense to go against this principle but at the same time this principle is not guaranteed to give you knowledge.

but its usefulness, to me, says nothing about its truth — Bob Ross

This is fair ; I am probably just less inclined tp believe that there is a strong line here between truth and models or that even truth is something that we can access beyond the restrictions of employing models.

Well the way I stated it in the OP was meant to just be a counterargument against irreducibility so that a physicalist could use it. But I think my view here is mostly just an argument against dualism. I don't think I am truly a physicalist, and clearly from various replies in this thread it can be seen there are some deep issues with turning the intuition of physicalism into a cohesive viewpoint but its the kind of intuition or view that reflects well on my sympathies so I often put myself on that side in a debate that can very polarized.

At the same time, as I have said in several posts in the thread, I also don't think we can have access to a good characterization of what a fundamental ontology could be. In light of this, I don't think my view of reality has a real base, it is just filled with the models we have from the natural sciences and how they relate to each other; my inclination then is that embracing ontologies centered around experience add to this network of models in ways that are either not necessary or not very interesting/useful from my standpoint.

I feel like my views don't need something more to explain existence because it appears to me from various areas of philosophy and neuroscience that as observers we are just naturally limited in how we can think and characterize the world and so there are just things about existence we cannot have epistemic access to in a coherent way. We cannot ever look at the world in a way that is independent of how our brains have been structured, the things that they are capable of doing and their limits.

Edited: paragraphing, "intuition of physicalism", "have epistemic access to"

1. Intuitions (i.e., intellectual seemings): one ought to take as true what intellectual strikes them as being the case unless sufficient evidence has been prevented that demonstrates the invalidity of it. — Bob Ross

Obviously your intuitions may be wrong but it also seems to be that I could apply the opposite rule and it wouldn't necessarily have an effect on how well I gather knowledge.

2. Parsimony (i.e., Occam’s Razor): entities ought not be multiplied without necessity. — Bob Ross

I just don't see why this needs to be the case. I can imagine someone applying this and it turning out that the correct option had more entities than they woukd have deemed necessary.

3. Coherence: the belief (in question) should cohere adequately with one’s higher-prioritized beliefs about the world. — Bob Ross

Your higher-prioritized beliefs may be wrong.

4. (Logical) Consistency: there ought not be logical contradictions in the belief nor in contrast to higher-prioritized beliefs. — Bob Ross

This one I agree with most and is most intuitive of what we want to do but at same time maybe sometimes we do hold inconsistent models about the world which nonetheless are useful.

That may be, I just thought that these rules would have to work all the time to be objective but I can imagine scenarios where the rules you suggest would sometimes would fail.

Its not about generating consciousness but the idea that if something putatively non-experiential can generate experiential concepts, this leads to absurdities which make dualism implausible. P-zombies are an example of such absurdities. Of p-zombies are biologically identical to us they will say they have consciousness and have thoughts on the hard problem of consciousness even if they don't have experiences. This is absurd which can then be used as an argument against dualism.

Yeah and how about that theory? How does it "arise"? "What" is it that is "arisen"? — schopenhauer1

Well I am just talking about the concept of qualia and the inability for some kind of statistical learning machine to explain their own concepts; for instance, because those concepts are too primitive and they are representations which do not carry information about how those representations are instantiated. For instance, if you look at how some neural network works where input units cause states of hidden units to change through weights and thresholds etc, you might consider the network to learn about information in those inputs but theres no viable mechanism that would allow it to learn about and represent how that information is instantiated.

That's only one form of dualism and even that is not entailed in physicalism. Physicalism doesn't have room for mental events other than hidden dualism (has been my premise for a while). — schopenhauer1

The point I'm trying to say there is that it would entail epiphenomenalism and epiphenomenalism is absurd so it cant be the case. It may allow some form of dualism where the physical and mental interact but i generally find this implausible because there is just no evidence or suggestion from science that this is or should be the case.

I think that isn't much of an argument other than we don't know. That is again, only one form of dualism, and it's one that's prone to physicalist accounts because it starts with the physical causing mental. — schopenhauer1

Its not an "I don't know". Dualism is either not empirically motivated or incoherent. This incoherence can be seen in the idea of a p-zombie which says it is conscious and believes in the hard problem of consciousness.

Emergence does have to be explained here. How is it that emergent properties exist prior to the viewer, and all that. It's bald assertion to just say that "and it emerges", it's about as explanatory as saying, "it's an illusion". — schopenhauer1

Emergence presumes dualism which I am not doing. I am saying there is no dualism.

Its all about the meta-problem of consciousness. If it is plausible for a physical statistical learning architecture to generate experiential concepts but be incapable of reducinh (correction) them to its knowledge of the physical world then it seems to render the role of phenomena in our knowledge of our own consciousness as epiphenomenal and absurd. The idea that a representation would not carry information about what physically instantiates that representation is one suggestion about why some kind of statistical learning architecture would not be able to reduce or explain experiential concepts it might generate.

My view isn't so much about falsifying qualia but about whether our concepts of qualia and their irreducibility can plausibly arise through information processing. If that is the case then it strongly suggests to me that dualism is an illusion because it would entail epiphenomenalism which is absurd. On the other hand it suggests one might be able to defend the identity between brain processes and qualia even if one cannot be reduced to the other. This would allow a physicalist to defend the notion that everything is physical, or more specifically that nothing extra is needed to describe reality.

I don't see the problem. It seems to me that under your characterization, physicalism would be falsified if there existed any concepts that were not physical: e.g. organisms, economies, mountains. They are all just labels that describe our empirical observations at different scales nd levels of abstraction. I can think of an observer the same way, I just mean more or less something that can respond differently to different inputs. That seems to be the kind of minimal characterization of information processing.

What do you mean?

I don't think there is anything problematic in entertaining both the mental and physical as concepts that we have constructed due to the nature of our brains.

In hindsight I think is-ought was a poor analogy/description for what I meant which was just that there doesn't seem to be a straightforward link between the evidence you accumulate and your decision to take up a belief.

In what sense would you say your norms are objective?

I think though that fundamentally, our natural sciences seem to characterize the nature of the universe with physics in a way that doesn't depend on the notion of experience. It is not needed for those models to work and would be adding something in addition which isn't required and doesn't make a difference to our understanding of the universe. I think therefore physicalism is more appropriate than panpsychism.

Thus, while we can abstract the picture from the photograph, and we can say that there are isomorphisms between different copies of the same image, these are causally irrelevant. — Count Timothy von Icarus

This doesn't violate causal closure due to the fact that everything about the world we create are models or constructs which depend on various contexts. The fact that I can create various different models of the world at different scales and levels of abstraction doesn't have a bearing on causal closure in this context.

I think people's characterizations of physicalism are generally quite vague which is why so many people are intuitive physicalists despite this criticism you gave which would trivially refute the strict characterizations of physicalism you and perhaps many other philosophers give it. I would look at physicalism more in terms of how central our physics models appear in our view of the natural sciences and therefore the world which is totally coherent with the idea of having various levels of abstraction.

Information is another abstraction and any notion of information depends on the ability for an observer or detector to make distinctions; information is therefore not really a thing but is something that can be characterized in the interaction between a stimulus and observer / detector. What this means is that any notion of information would be at least implicitly embodied in the physical processes that enable an observer to make distinctions (e.g. so that I can recognize a photo or a neuron can selectively respond to different inputs): the information is physical, just not in any way independent of an observer.

Physicalism says that everything that can be known about seeing red is physical. There is nothing else. Perhaps experiencing red is a different experience than knowing "how red is experienced." This is fine, but it's going to lead you to physicalism with type or predicate dualism (which may or may not be physicalism depending on who you ask).

The thing about what you're saying is that it suggests that our notion of ontology about reality should be limited by our inherent capacity to perceive or think about it which I don't think is the case. The fact that I can conceptualize reality with both mental and physical concepts or that there are limits to how I can directly perceive reality should not necessarily be confused with reality itself.

In fact, I can plausibly imagine a completely physical world where you have a physical machine which receives sensory inputs about the world, learns their statistical structure and creates theories about the world. I can totally imagine trivial contexts where that machine would be incapable of explaining aspects of its own inputs and reconciling them with its own physical models... would that entail the physical world exists in has things that are not physical? No, its just the limits on what a machine can explain.

If physicalism isn't going to fall to Hemple's dilemma and define itself as "just whatever currently has evidential support," it seems like it has to pick a hill to die on, and superveniance is the most obvious hill.

To be fair, I think similar sorts of problems show up for idealism — Count Timothy von Icarus

As said in a previous post, I think that the idea of fundamental ontology is inaccessible to us, perhaps cannot be made coherent. My characterization of physicalism is more about the role of our models of physics and I guess the natural sciences more generally
in our view of reality and arguing against the need to posit ontologically separate mental phenomena above and beyond them.

This just restates the problem that is supposed to be revealed. — schopenhauer1

I disagree because the problem as usually is seen as telling us about ontology, and I am rejecting that view. The disparity in her concepts or in the types of information she perceives should not necessarily be equated to facts about the world of the world. This would assume she has direct access to the world, which she clearly doesn't because she is only capable of knowing or perceiving what she does because of the specific structure of her brain and how it interacts with the world. I think this is enough to say that her conceptualizations and knowledge cannot be seen as being objective.

And let's not dwell on Mary, I just mean the implications of any of these thought experiments. That is to say, it's not about the information processing, but why it is that the information processing is accompanied by "what it's like" qualities. That is to say, a zombie is basically behaving internally (neuronally) and externally (outward movements) just like a normal human, except there is no visuals, hearing, etc. — schopenhauer1

For me, the purpose of the zombie thought experiment is that the idea that there is some separation between "what it's like" qualities and information processing is totally incoherent. If this were the case then it would render "what it's like" qualities totally causally redundant since the zombie with no experiences knows everything about the experiences their non-zombie counterpart has and comes out with the same philosophical quandries about the hard problen of those experiences (even though it doesn' have any). It makes no sense as it would mean that even though I am seeing and experiencing things right now, those visceral "what its likes" have no bearing on my knowledge and my reports about my own experiences.

At the same time, if brain activity is the cause of my reports and knowledge but is only caused by other physical causes then how am i getting knowledge of those disembodied experiences that are inherently different from and don't interact with the physical. The fact that my experiences and also my knowledge of those experiences line up is totally coincidence which seems absurd and requires a convoluted way of conceptualizing how reality works. This is a much deeper problem than simply the irreducibility of consciousness - another word for it is epiphenomenalism and it just seems totally an incoherent way of viewing how reality works. The simplest solution is that the separation between "what it's like" and information processing doesn't really exist - there is no duality.

Why do we still think of there being some inherent difference? Because our information processing apparatus makes us think there is; afterall, we do not have direct access to what the world is really like. I think a lot of philosophical thinking in this area seems to assume that we just have direct access to things but I don't see how this can be the case when our thought, perception, concepts depends directly on our brain. I don't even think we should assume that just because we experience something we have direct access to knowledge of what is actually going on. Why should we assume this kind of thing comes for free? Does it come for free for cats, insects, fish? I don't think our brain structure or perhaps even any type of brain structure can allow us to satisfactorily answer the question of "what" is mental event X. At the same time I think we can deduce logically that a fundamental dualism between the mental and physical could be illusory.

Yes, the physical description doesn't entail knowing what red is like and vice versa but notice how her saying "aha, I know what it is like to see red" is caused by brain activity which is causing her motor neurons to fire and let out those words. It is photoreceptors and neural activity as a consequence that allow her to even see red. Clearly, the only reason she knows what red is like is because of her biology.

Now imagine a p-zombie Mary, identical in every single way biologically except for the fact she does not have experiences. She hasn't got certain kinds of photoreceptors so she.. or her biological machinery at least... cannot distinguish wavelengths of light at all. She suddenly gets gene therapy which allows her to produce the pigments necessary to distinguish wavelengths of light ... "aha, now I know what its like to see red!". Zombie Mary is going to say this because she has identical Biological machinery to normal Mary even though she does not even have experiences. Not only that, but because she has the same biological machinery, the causal dynamics of brain activity is going to lead her to say things like "I cannot reduce these colors to the other physical facts I know about the world". Zombie Mary is going to know everything that Mary knows about her experiences without even having them. Without even having experiences she might be able to evem understand and anticipate other people's experiences... tell them that they will find a particular picture beautiful or that a perfume smells of a mix between strawberries and roses, which other people would agree with.

Isn't it strange that Zombie Mary knows all these things about experiences without having them. Does Mary actually having experiences make a difference to her knowledge of those experiences which come about due to neural activity? It doesn't seem so. Why would Zombie Mary find that experiential concepts are difficult to reduce to scientific concepts when she doesn't even have experiences?

This picture of a Zombie Mary is kind of incoherent in that a Zombie Mary knows all about experiences and Mary's actual experiences seem to have no causal effect on what she knows or even reports about her own experience. What this picture tells me is that even though Mary discovered something new, this has nothing to do with a novel thing appearing before her eyez but about changes in her brain. The reason why she might not be able to reduce this experience to physical concepts is similarly to do with the brain and the nature of the information the brain processes. I think this is closer to the idea that Mary gains a new ability rather than learning a new fact about something novel that exists in the universe.

The only way to make the picture coherent, so that Mary's experiences are not redundant when it comes to her knowledge of her own experiences, is to collapse the dualism between physical and mental. Her experiences and neural activity effectively must be the same thing to respect the fact that her experiences are causally efficacious but also that her biology is clearly what causes her information processing abilities and accounts for her knowledge of her experiences. The irreducibility we find then doesn't reflect an ontological distinction because clearly her seeing red for the first time isn't about a new different kind of thing to the physical. Instead, it is of an epistemic nature in the context of information processing in the brain/mind; she has physical and mental concepts which are constructed in a certain way, but these are concepts created effectively through statistical machine learning in her brain to understand what she perceives; they don't necessarily reflect the actual intrinsic nature of the world. She cannot perceive the intrinsic nature of the world that is independent of the particular structure of her senses or the brain/mind she that receives information from it.

Intriguing! I have at times thought about conceptualizing reality in terms of information. I think I have quite a way to go before I can consider myself to have a precise well-thought out kind of manifesto about what I actually believe about reality or how I should view it. Still have to think out a lot of kinks.

And yes I agree with you in the sense that I don't think its necessary to get rid of a divide between mental concepts or the notion of experience vs. physical ones.

I think maybe there is still a kind of something like an is-ought problem in epistemology in the sense that people may have different amounts of evidence regarding some hypotheses but the fact that I have evidence doesn't follow that I should take up one belief or another. Some people may take up a belief on very little evidence and some on a lot more.

I think Mary's Room is a very good argument against the reducibility of experiences to physics but I don't think that it entails that this is because experiences are some kind of thing out in the world being missed out on.

I would expect that in principle we can derive Mary's reaction of "aha, now I know what it is like to see red" from a complete physical description of her brain processing. If her ability to see color is mediated by physical photoreceptors and physical communication via neurotransmission then her new knowledge of red is due to physics, not some unique experiential thing like qualia which she has a kind of special ability to detect. Similarly, her inability to make the reduction from red to physics is something that is a consequence of her brain activity and the type of information she is processing in that activity.

Her new knowledge of red then may not be a physical fact in the trivial sense that it is not part of her understanding of physics, but it is not necessarily a consequence of something about reality that is being missed in a particularly significant way. What she can or cannot perceive is a direct consequence of physics.

Not at all, the metaphor has a completely physical basis so how can it be an argument against physicalism?

I would say that information content isn't a thing in and of itself but is about what an observer can distinguish.

My point is not really 1 or 2 but an inversion of 2 - how can an observer infer the material content from the image.

The photo thing I think isn't so much supposed to be an analogy for the physical and mental per se but of the relationship between representations and the mediums that hold them. Perhaps a better way to put it is that the information is about what is being represented and nothing else. Experiences are representations of things in the outside world. If they had information about what is going on inside your head they would be bad representations and our neural architecture isn't designed to represent that information. There is no reason to expect that the representations of our experience should be reducible to whatever is going on inside our heads if they serve the proper function of representations.

The photograph absolutely does have information about the medium that it is made of. I can subject a photo to all sorts of chemical tests. I can identify what it is made out of, what it dissolves in, etc. I can discover fingerprints and DNA on the photograph, which will help me determine its history.

But I am talking about the information contents of the actual image, you are talking about features of the physical object the image has been projected on. I can produce the same image on different paper or have it on a digital screen and identify the contents of the image; those contents are not directly related to the physical composition of a photograph you can hold in your hand and cannot be reduced to it, which is the main point.

Yes, it's true that that image is not totally independent of other factors; after all, the type of camera and resolution etc will have an effect on the image but these largely still come from the same interactions during the photo-taking process by which the image of Everest was stored - it is still information of the image which is independent of the physical medium an image is projected on and so cannot be reduced to it.

how the photo got there

I wasn't very clear at all when I said this because I didn't anticipate it to become a topic of the convo but I actually mean't to say the actual physical process by which the photograph was created in the moment through light reflectance and absorption and what ever complicated physical processes are involved. This can't be inferred just from looking at an image.

The film itself will tell me what type of device was used to take the picture and I can then use my computer, a physical device, to find all sorts of information on the exact physics that would allow a person with a camera to create such a picture.

Yes and this is what we have done in neuroscience but the point is that that physical information is not directly inferrable from the image itself, it relies on additional empirical observations extraneous to the features of the image, e.g. the arrangement of color parameters that form what we can identify as the image.

You seem to be setting up some sort of dichotomy between the "image" on the photograph and the physical photograph. But physicalism is an ontology that explicitly denies that any such dichotomy exists except in our minds. Film is physical. It encodes information about the pictures taken with it by virtue of physical processes. And, in comparison to how minds are generated, the physical processes involved in photography are very well understood in physical terms and arguably already reducible to them.

Well I don't think there is necessarily a dichotomy in the way you suggest since the information in the photograph is being perceived and interpreted through a physical process - whatever person or perhaps even machine, computer program etc is reading the image.

But the point is that to read the information in the photo, whatever machine has to be designed to distinguish arrangements of color parameters or inputs that map to those arrangements. That information is the contents of the image but nothing in that arrangement will tell you about the medum that image is projected on. I can imagine a circle, see it on a computer screen, see it on paper. What tells me that that image is a circle and differentiates it from non-circles has nothing to do with some kind of medium it is represented on.

When physicists do make ontological claims, they increasingly seem to be embracing various forms of immaterialism, mostly ontic structural realism, rather than physicalism

I think this is splitting hairs really for the purposes of the part you quoted because whether you're talking about ontic structural realism or physicalism, you're not changing the central role of physical constructs in the universe amongst other constructs. If you look at people like James Ladyman, they are expressing the same kind of sentiment as in that quote; they try to produce a more rigorous characterization of reality which can essentially be used as a vehicle for their naturalism, empiricism.

I have to go but I will reply to this in a couple of hours!

Thanks btw!

I don't know how well what I am about to say will come across but ...

I don't really understand what immaterial meaning ... means. To me, meaning is like a construct we use to refer to our own understanding and knowledge which is directly embedded and enacted in the dynamics of experience...

In other words, meaning is just use. Use is just dynamics of experience which reflect dynamics of neural activity.

Meaning can therefore be deflated in terms of being implicit in these dynamics as opposed to being an explicit thing

The problem is that this implies that not everything can be explained in physical terms. So, this cuts against many common formulations of physicalism, such that "a complete physics can, in principle, explain everything."

I am not sure I totally agree. In the OP I suggest that irreducibility is a natural consequence of the fact that experiences are representational. I then don't think that it is coherent for a representation to be reducible to things that cannot be identified with what is being represented, like with the photo example: a photograph of Everest contains information about everest, it does not contain information about the medium the photo is on, how the photo got there, what physical processes enable us to see the information in the photo etc.

It doesn't seem coherent to me that we should be able to gleam that information if the photo was a veridical representation of Everest. That the photo doesn't contain this information is not a fault, its exactly what the photo is supposed to do. The fact that experiences cannot be reduced to the physical then is not some kind of epistemic gap that it should be possible for us to breach; no, if experiences are representational then it is impossible to explain this in the same way that a round square is a logical impossibility. We should not expect physicalism to explain this kind of thing.

At the same time, it might be possible for the physical to demonstrate this kind of thing in principle through things like machine learning where we design an architecture for some artificial intelligence and describe the information it can process, describe the limits of what it cannot process or explain. This is speculative but I think that is a plausible avenue which is a surrogate for an explanation; for instance, if we create an advance A.I., it might start to say that it has experiences that it can't explain consistent with what we say about how our own experiences are irreducible.

Obviously, someone may just say that experiences emerged somewhere along the development of this A.I. but then the interesting part would be if we can explain why the A.I. is saying these things purely through the dynamics and mechanics of its architecture without recourse to explicit experiential constructs, which is exactly how a physicalist might want to explain away the irreducibility. If we cannot help but find our experiences irreducible as a consequence of the nature of what our brains are doing, then we may have just explained away irreducibility without needing to say that this irreducibility is because the mind and brain are distinct entities.

But then what exactly is it that makes nature "physical?"

If physical facts can only describe one set of things in the world, then it seems like "physical" is a subordinate category, and that a higher category should subsume both the physical and the mental aspects of reality...

The question then becomes: what does physicalism explain that other ontologies cannot and how does it differentiate itself from objective idealism aside from a bald posit that nature is essentially "physical?"...

The dividing line would seem to be the claim that there is something that is ontologically distinct, a substance or process that is "physical," and that this physical substance/process somehow supervenes on all that is mental in a way that is relevant enough to be worth positing. That is, physicalism has to have some sort of extra explanatory value to it after we allow that it cannot explain/describe all aspects mental phenomena. — Count Timothy von Icarus

I think from my perspective, it's not so much about some kind of physical substance as the kind of models we have about the world. As you say, the idea of a physical substance is ill-defined and vague; however, the models that have emerged in the natural sciences seem to be successful and I think that is what we should follow when trying to decide the best way to describe things that actually exist.

For me, it is very explicit that physical models are constructs which have been created by us, biological machines. I am not sure scientific models allow us to do more than predict things in some type of fashion which is directly situated and embedded in our own experiences. There isn't necessarily even a strict dividing line between predictive scientific models and other types of models in our experience; in modern neuroscience, the brain is a predictive machine which mediates all our models whether in the sciences, humanities, the way we use language, folk physics, our understanding of social situations or our own mental concepts etc.

There is therefore room for all sorts of constructs in our mind and they are just that - models! For me its trying to pick the best ones for some purpose, not necessarily turning these models into concrete substances. There is not necessarily a strict difference between models we have for things in physics, chemistry, biology, economics etc, and I don't want to say these each have their own fundamental substances either. I am agnostic, even anti-realist perhaps on that kind of thing, nonetheless there seems to be a strong intuitive picture that emerges in the natural sciences about how some constructs e.g. ones in physics seem more fundamental or to have more primacy than others. The value of physicalism then is in the value and power of physics in the natural sciences.

Someone might say this kind of physicalism is difficult to explicitly differentiate from an objective idealism but then again to say you are idealist seems to me to be adding something extra on top of the advocacy of these models in the natural sciences as opposed to just taking the explanatory value of those models at face value.

Obviously all these models are actually embedded and situated in experience as has been said. The physicalist would then say that this experience is identical to the physical just that there is no coherent way of making the reduction from the information represented in conscious experiences and the models of the physical we have constructed in conscious experience, also situated in those representations. The point of the OP is supposed to be that if irreducibility can be explained away as due to the nature of information processing in our brains then the identity between experiences and the things in physics can be defended, we just have an inherent inability to explain it in the same way that a machine learning architecture has inherent limits on what it can do or how self-reference has inherent limits.

So maybe the lesson is just to abandon "physicalism" and embrace "naturalism, monism, and realism?"

Yes, I think you could view it this way though I think the argument in the OP can also be used to defend physicalism. I think it depends on someone's inclinations; yes, physicalism is poorly defined but terms like "monism" or "naturalism" are no better I don't think. Yes, maybe it would be more true to say something like we cannot access the fundamental ontologies of nature but I also think physicalism does capture something more about my inclinations than the other labels, and captures how physics does seem to take a central role in my understanding of what exists. In some ways its actually a more honest characterization of my views and attitudes than something like neutral monism

@RogueAI

explaining how it happens

A: In my view, rejecting the duality of mind and body makes explaining how conscious happens an invalid question.

reducing it to brain states

B: I personally don't believe that consciousness can ever be reduced to brain states but I don't think this is a fault of a physicalist model but can plausibly be explained away as a consequence of limitations or quirks in information processing.

arguing successfully it doesn't exist at all

It depends what is meant here. Imo the natural sciences point to dualism being false because 1) science has found no evidence of separable mental substances that are separable from physical phenomena. 2) science seems to suggest that physical constructs are sufficient for intelligence, perception, cognition etc.

So I think science suggests something like monism. I think its then reasonable for someone to take a physicalist world view since the constructs we find in the natural sciences are the kinds of things a physicalist universe would be based on in principle. I think maybe a physicalist might say that they aren't denying we experience things just that they are nothing above the physical.

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Obviously some people have said that the natural sciences more or less only describe the behavior of things not what things actually are intrinsically - they are free to posit that this stuff is phenomenal. But I think in light of points A and B above and the difficulty of creating a coherent, non-trivial definition of what conscious phenomena actually is, I don't think someone who identifies as a physicalist can be accused of failing to explain anything anymore than a physicist can be impelled to explain why anything exist at all and there isn't just nothing.

The physicalist is therefore not necessarily be saying that "non-conscious, mindless stuff" doesn't exists just that it wouldn't be anything above the physical and anything about it that can be meaningfully explained about it can be done through constructs from the sciences.

I might even go as bold to say that this kind of physicalism I am envisioning might be compatible with someone who believes that the universe is phenomenal as long as they believe that there is nothing more to explain about it than through the constructs we find in the natural sciences, which I think would probable render their concept of phenomena a bit explanatorily redundant and inaccessible, perhaps useless.

I think what should be abandoned is the metaphysical assumption of some kind of dualism where over here sits physical things and over there sits mental things and they are totally separable. In that regard, the idea that matter generates consciousness is based on a faulty assumption.

So that even while you recognise something like the 'explanatory gap' or 'the hard problem of consciousness', you think physicalism is a pretty safe bet regardless

I don't think that characterization describes the view I promoted so well. I think the explanatory gap is significant enough to question physicalism but I think that if that explanatory gap can be explained away as being due to limitations or quirks of information processing then there is no reason to think that explanatory gap is a consequence of some intrinsic ontological distinction.

I think rather than an argument explicitly for physicalism, it is a counter to arguments used against physicalism specifically that use irreducibility to say that the mental and physical are different. But since the idea of what the physical actually is is a bit up in the air or ill-defined I don't think the argument can be used as a way of ruling out idealist, panpsychist or neutral monistic who might just say something like physical things are actually just mental things. But I think the main significance is the argument is a defence for the physicalist against irreducibility.

There's definitely some stuff in what you have written which resonates with the direction I want to go in generally when it comes to my philosophy of mind - what kinds of information are available to us and how tjat impacts the explanations we can give about what we perceive. Only I would resist the idea of meaning being immaterial. I'm sympathetic to view that kind of deflate the status of meaning as a thing.

How do you do itallics here?

Yes, I guess it is a kind of non-reductive physicalism but the root of the irreducibility is explicitly to do with information processing. I see the surface resemblance to Davidson's view but I anticipate there's probably a fair amount in his view I would disagree with. I cant say I'm too familiat with it though, it seems like quite an involved view of the mind/brain.

Well, all I can say is I disagree then. I think the photograph metaphor seems a coherent analogy of the view and that I think it is consistent with someone being a physicalist.

Yes, I think there is an important point here if I understood correctly. We can say we have experiences but I don't think they necessarily tell us anything much at all about anything and I think even if experiences are so immediate and visceral to us, they don't necessarily allow us to make conclusions about the nature of the universe. In fact I would say I am inclined to say reducibility or explanation never comes for free and any reductions we make requires prior assumptions that don't necessarily seem well justified - all knowledge is susceptible to the munchausen trilemma.

I think your view is too restrictive of physicalism; how would you characterize what my view is saying then? I would say its plausibly fully physicalist because the reason for the inability to reduce I think can be explained physically, for instance through the limitations of what a computing / information processing device can or cannot do. Look at the photograph example too - the explanation for the information a photograph contains is obviously physical - a photograph doesn't contain information about the medium it is represented on for physical reasons, it doesn't contain information about objects obscured from view for physical reasons.

This is an interesting and good point. We can only go by the evidence of what science gives us which looks like a complicated picture of an outside world beyond our experiences. I agree that there is nothing that necessarily makes our representations actually exactly true, objective, totally veridical representations of what is going on - I think that is probably impossible for various reasons and perhaps the ways we can view the world are chronically underdetermined/indeterminate. Nonetheless, I don't think it is unreasonable for someone to defend a physicalist view, depending on how they conceptualize it, given the success of the natural sciences and what they seem to say. My focus on this post was that if someone chose to be a physicalist, then the irreducibility of experience would be the main argument against their view, and I was looking at a counterargument.

But you are presupposing that everything has to be explained in some kind of reduction but the point is that if what we experience are representations or information about the outside world then such a reduction is incoherent. Its not like there is some explanation or reduction out there in principle that we just dont know, its that such a reduction does not make logical sense, like how paradoxes don't make logical sense. If such a reduction is not coherent then I dont think the failure of that reduction can be an argument against physicalism.