Chapter 2: The Argument against Physicalism

[hypnagogue]

This chapter serves as the entry point into Rosenberg's development of a Liberal Naturalist theory of consciousness and nature as a whole. Rosenberg argues that physicalism cannot do the job of accounting for p-consciousness, which will motivate the case for constructing a substantial new theory of the world that can readily accommodate it.

Physicalism is the view that all the facts of nature are physical facts, or are entailed by the physical facts. Physical facts are facts about those phenomena considered to constitute the fundamental ontology of physics, such as mass, spin, and charge, including the causal powers governing their respective behaviors, such as gravitation and electromagnetism. Physicalism, then, claims that the only fundamental 'building blocks' of the world are those phenomena taken to be fundamental by physics, and that every non-fundamental phenomenon in nature-- be it a chair, an economy, or a subjectively experiencing mind-- can be constructed by the proper configuration of these fundamental, physical building blocks.

Rosenberg attacks physicalism directly by arguing that the general kind of facts a physicalist theory has at its disposal are not sufficient to entail the general kind of facts that obtain about phenomenal consciousness. Thus, his argument is inherently different in character from Frank Jackson's Knowledge Argument and David Chalmers' Conceivability Argument, and cannot be dismissed as an argument from failure of imagination.

The general form of Rosenberg's antiphysicalist argument is as follows.

1. The facts about a pure Life world do not entail facts about phenomenal consciousness.
2. If facts about a pure Life world do not entail facts about phenomenal consciousness, then facts about a pure physical world do not entail facts about phenomenal consciousness.
3. Therefore, facts about a pure physical world do not entail facts about phenomenal consciousness. (p. 18)

Rosenberg uses Life as a kind of toy physics whose essential properties we can grasp and analyze cleanly, without carrying any of the conceptual baggage or unwarranted/unnoticed assumptions that might come with our conception of the world's actual physics. He then imports the basic structure of his analysis of Life's toy physics into his analysis of 'actual' physics to come to the same general conclusion about what it can say about p-consciousness.

Life is a kind of cellular automaton with its own well-defined 'space,' 'time,' causal properties, and causal rules, which together comprise a sort of 'laws of physics' for a Life world. A pure Life world is defined as a world whose fundamental ontology consists only of those facts stipulated by Life's 'physics.' Pure Life worlds consist only of 'bare differences,' meaning that all of a pure Life world's properties are stipulated to exist in a purely formal, schematic, relational, contentless manner. Bare differences can be understood as differences that are stipulated to exist at the very 'ground level' of a world, rather than differences that arise as a result of some further internal structure or grounding intrinsic content. They are not differences that obtain because of some more basic facts; rather, they are the most basic facts.

Rosenberg argues that p-consciousness contains qualitative content that can be epistemically accessed via observation, and that bare difference alone cannot entail facts about such content. He acknowledges that families of qualia (e.g. the set of all colors, the set of all tastes) exhibit various inter- and intra- family difference relations, but argues that these relations are not merely formal or schematic, but rather that they obtain in virtue of the particular properties of the observed qualitative bases. On this view, we might say that qualia are not just schematic/formal relationships, although the manner in which their inherent properties are naturally related to each other do happen to instantiate such relationships. Thus, in the sense that bare differences are contentless and ungrounded, qualitative differences are contentful and grounded-- they are not bare, but rather they are ontologically 'rich,' derivative on a qualitative, intrinsic basis. According to Rosenberg, we cannot derive such a contentful basis from an entirely contentless schema. It therefore follows that the facts of a pure Life world do not entail facts about p-consciousness.

Rosenberg goes on to argue that a pure physics world-- a world whose fundamental ontology consists only of those facts stipulated by physics-- cannot entail facts about p-consciousness, for the same general reason that facts about a pure Life world cannot entail facts about p-consciousness. He argues that the facts of a pure physical world consist entirely of bare differences; they are a stipulated set of relational, formal, schematic facts with no grounding, intrinsic basis. Thus, a pure physics world is saddled with essentially the same problem as a pure Life world: its ontology of bare differences cannot entail the observed qualitative content of p-consciousness. Since physicalism essentially claims that nature is a pure physics world, and since p-consciousness is observed to exist in nature, it therefore follows that physicalism must be false.

 

[Canute]

Apologies but I'm still a little unclear about what p-consciousness is and what it is not. I really do want to get to grips with this but always have a problem whenever the term appears, and whoever is using it. This is partly my stubborness (I'm reluctant to split consciousness into a, b, c, d and so on), but also for another reason.

If p-consciousness has a meaning as a term it is because it is contrasted with something else, let's say a-consciousness. But if a-consciousness is an aspect of consciousness then it is a-consciousness and p-consciousness together that add up to consciousness. If this is not the case then why have two terms? It then becomes unclear how one could explain one without explaining the other and the whole distinction between them starts to look a bit odd. Chalmer's prefers the term 'experience' to p-consciousness and so do I. Can I assume in this discussion that p-consciousness means experience, or 'what it is like', and that the 'p' word is superfluous?

 

[hypnagogue]

Chalmer's prefers the term 'experience' to p-consciousness and so do I. Can I assume in this discussion that p-consciousness means experience, or 'what it is like', and that the 'p' word is superfluous?

I don't have time now for an extended reply, but briefly, yes. P-consciousness refers to the same thing as "what it is like" and Chalmers' use of the word "experience."

The 'p,' however, is not superfluous. Consciousness is a vague word that picks out many meanings, and not all of its meanings are equivalent with "what it is like" and Chalmers' "experience." For instance, sometimes "conscious" is used synonymously with the word "awake," but this is not what we mean by experience; it's coherent to deny that, say, there is something it is like to be a dog, but also to acknowledge that a dog cycles through stages of wakefulness and sleeping. The 'p' in p-consciousness just means that we are isolating that meaning of the word "consciousness" that is identical to what we mean by "what it is like" and "subjective experience."

 

[selfAdjoint]

I want to be clear here about these "bare differences" of physicalism versus the "content-ful differences" of p-consciousness. Take the prototype quale, color. Coming to the eye is a bare difference, frequency. The retina has opsin molecules specialized to react to different frequencies (only a few different frequency bands); the whole frequency distribution is reductively coded into the response of the molecules to these discrete bands. The contortions of each opsin molecule causes an electrical signal (more bare difference) to be sent to the visual cortex. Neurons in the visual cortex perform an arithmetical subtraction of the different band signals, and these (bare!) difference signals are sent on. Ultimately (we don't have detail from here on) there may be a small group of cells that constitute our understanding of red, and the activation of this group constitutes the presentation of "red" to our consciousness - all bare differences so far. What is the content that can be RELIABLY inferred for the quale red aside from the fact that this node has been activated? Is the content derived from some direct apperception of the exterior world, apart from the visual system? Or is it just "what it is like" to have the "red" coding neurons active?

 

[hypnagogue]

selfAdjoint, please observe the forum guidelines and post any questions and commentary you might have in Metaphysics & Epistemology if you are not reading along with the group. If you have indeed purchased the book and are reading along, please notify me and accept my apologies. Thanks.

 

[Canute]

OK. I'm happy with that. (We disagree on whether it's coherent to say there is nothing that it is like to be a dog, but that doesn't matter).

Do you think it would be fair to say that Rosenberg's argument here, if we swap the terms around, is that physics is founded on the study of bare differences, and that therefore it does not have a fundamental ontology?

 

[honestrosewater]

We can observe that a pattern of differences between colors can produce another color. For instance, a field of tightly packed yellow and red dots may yield an experience of phenomenal orange under the right viewing conditions. However, we can also observe that the shade of orange that results is not produced by the mere pattern of difference. It has to be a pattern of difference between the appropriate colors thus providing no explanation of color in terms of mere patterns of difference.

If we try to abstract the patterns of difference from their contentful bases, viewing colors as mere difference structures, we see that the result is multiply realizable and some of the realizations do not yield orange. For example, one can instantiate the same structure of differences between two other colors whose hues lie at the same distance from each other as red and yellow (e.g., yellow and green). A pattern of dots of these colors will yield a different color from orange. Therefore, we can observe an identical structure of formal difference but different colors. The example shows that, even allowing that we start with colors, one cannot reduce some colors to the mere difference structure among other colors.

1 and 2 "lie at the same distance from each other" as 2 and 3, so 1+2=2+3. That's what it seems he's saying.
Edit: Er, I didn't mean to point out anything about the particular structure of arithmetic, it's just handy as a generic example. I don't want to get sidetracked so I'll try something else.
If colors can be structurally distinguished from each other, a structure composed of different colors is a different structure. If colors can't be structurally distinguished from each other, how does his example get off the ground? If a red dot is not a yellow dot is not a green dot, a field of red dots and yellow dots is not a field of green dots and yellow dots; The two fields are not identical structures. He seems to be doing what he has just finished complaining about: "Reification of the difference structure as basic ignores the grounding of those differences in each specific case and so ignores the content instantiating those structures." He is ignoring the structural role the colors play. In the original structure, colored dots- not mere dots- are the fundamental structures. In the new structure, red is yellow is green. He has removed the structure not the content- as far as the structure is concerned, fundamental structures have no content. I'm almost certain he knows better, and it's just that I'm missing something, but I can't figure out what. It doesn't yet even seem to matter that there are two levels of colors (dot-level and field-level). Maybe I should just skip the examples.

 

[Canute]

1 and 2 "lie at the same distance from each other" as 2 and 3, so 1+2=2+3. That's what it seems he's saying.

Isn't he saying the opposite to this, that there is a difference between 1+2 and 2+3 that depends on the nature of the integers involved, and not just on the relationship between the them?

 

[loseyourname]

I think that trying to find examples of the abstractions Rosenberg presents is proving to be rather cumbersome. Colors can be reduced to patterns of bare differences in quantum numbers from photon to photon. In fact, I don't even think he is really claiming that colors cannot be reduced. He is claiming that the experience of color is what cannot be reduced, and in general, that experience itself cannot be reduced, whether it be the experience of color or the experience of anything else. A lot of his examples are coming across this way. With the phosphenes, I think it is well-known that they are representational of physical events taking place somewhere in the optic structures. Even imagined images can be correlated with specific brain events. Many of his examples seem to run counter to his arguments in this way. In fact, I almost feel like I can follow better simply by taking heed of his abstractions and largely ignoring his examples, but obviously I'm not going to do that.

Anyway, to address the argument presented here:

1. The facts about a pure Life world do not entail facts about phenomenal consciousness.
2. If facts about a pure Life world do not entail facts about phenomenal consciousness, then facts about a pure physical world do not entail facts about phenomenal consciousness.
3. Therefore, facts about a pure physical world do not entail facts about phenomenal consciousness. (p. 18)

I've raised my objections to this briefly in a couple of other threads. I don't see how the truth of 1 is clear. I'm not sure how we could ever know exactly what a Life world could produce. In fact, that's the very appeal of the Life world. I'm not saying that I think a Life world does entail facts about consciousness, but where is the proof that it does not? I had the impression in the other thread that Gregg was claiming that a mathematical proof of this does exist. I find myself wondering, though, how that could even be possible. What kind of math can demonstrate either the existence or non-existence of consciousness?

My objection to 2 is a little more pointed. In fact, I think it is demonstrably false. Unless he really can produce a mathematical proof, he seems to be contending that 1 is true simply because we've never observed consciousness to exist in a Life world. But we've also never observed breathing, or bubble baths, or novels to exist in a Life world. Using similar reasoning, this argument could be constructed:

1. The facts about a pure Life world do not entail facts about breathing.
2. If facts about a pure Life world do not entail facts about breathing, then facts about a pure physical world do not entail facts about breathing.
3. Therefore, facts about a pure physical world do not entail facts about breathing.

As valid as this argument is, it is hardly compelling. I'd like to know why he thinks his argument is.

 

[hypnagogue]

Colors can be reduced to patterns of bare differences in quantum numbers from photon to photon. In fact, I don't even think he is really claiming that colors cannot be reduced. He is claiming that the experience of color is what cannot be reduced, and in general, that experience itself cannot be reduced, whether it be the experience of color or the experience of anything else. A lot of his examples are coming across this way.

Yes, he is arguing that physics has an ontology of bare differences, and that subjective experience cannot be reduced to bare differences.

With the phosphenes, I think it is well-known that they are representational of physical events taking place somewhere in the optic structures. Even imagined images can be correlated with specific brain events.

It depends on what we mean by representational. I think the sense of the word Rosenberg meant in chapter 1 is close to this one: "A state has a representational property when, to put it intuitively, it has a meaning or somehow stands in in some process for something else, such as an object, or a `proposition' ± a putative fact" (from http://people.cornell.edu/pages/beh24/rep.pdf ). One interpretation might further say that a qualitative experience Q is representational for a subject S if S takes Q to have some sort of meaning. It would seem to be safe to say that a visual experience as of a rock is representational for all cognitively normal, non-infant humans: we take such an experience to mean that there is a rock in the external world, sitting in front of us. But for a person who is not particularly educated about physics or physiology and does not hold supernatural beliefs, the experience of phosphenes probably has no particular meaning; it's just an experience, and not indicative of anything beyond itself. For such a person, phosphenes are not representational, as the word is defined above.

I don't see how the truth of 1 is clear.

Rosenberg argues for the claim that the facts about a pure Life world do not entail facts about phenomenal consciousness in section 2.5. If you are not convinced by the argument, can you pick out what specific points of the argument you have issue with? Can you produce counterarguments to these?

Using similar reasoning, this argument could be constructed:

1. The facts about a pure Life world do not entail facts about breathing.
2. If facts about a pure Life world do not entail facts about breathing, then facts about a pure physical world do not entail facts about breathing.
3. Therefore, facts about a pure physical world do not entail facts about breathing.

As valid as this argument is, it is hardly compelling. I'd like to know why he thinks his argument is.

The argument is not sufficiently general that we can rephrase it as "if facts about a pure Life world do not entail facts about X, then facts about a pure physical world do not entail facts about X," for any phenomenon X. It should be clear from section 2.5 that the argument gets its traction from consideration of bare differences and qualitative content. If your argument about breathing really did use similar reasoning, it would argue that facts about breathing include facts about qualitative content. At this point it would run into trouble, because we don't seem to have any reason for believing that the process of breathing involves anything qualitative. However, Rosenberg argues that we do have reason for believing that phenomenal consciousness has qualitative content, again in section 2.5.

 

[Fliption]

Am I the only one struggling to understand? Heh. I'm no where near being in a position to critique this idea yet. I bow to those who can.

As is obvious from some of the responses here, it seems a key point to this argument is Premise 2: Consciousness contains qualitative content (page 19). There is discussion in this section for 2 pages about the concept of "Observables". I need help here. I'm not clear on exactly what is meant by this term(other than the obvious meaning :uhh:) nor why it is relevant to a qualitative content argument. Can anyone help me out here?

Depending on my understanding of premise 2, I may or may not have issues with premise 3: Bare difference does not entail qualitative content.

 

[hypnagogue]

As is obvious from some of the responses here, it seems a key point to this argument is Premise 2: Consciousness contains qualitative content (page 19). There is discussion in this section for 2 pages about the concept of "Observables". I need help here. I'm not clear on exactly what is meant by this term(other than the obvious meaning :uhh:) nor why it is relevant to a qualitative content argument. Can anyone help me out here?

Rosenberg defines what he means by observables at the top of page 20. He argues that we are justified in believing that p-consciousness has qualitative content on the basis of first person observational evidence, so he needs to defend the premise that they are even observable in the first place. (As he mentions, some philosophers find the claim that qualia are observables to be problematic.)

 

[hypnagogue]

Do you think it would be fair to say that Rosenberg's argument here, if we swap the terms around, is that physics is founded on the study of bare differences, and that therefore it does not have a fundamental ontology?

My understanding is that it is correct to say that physics does have a fundamental ontology, albeit one based on bare differences. You could say that the fundamental ontology of physics is bare or barren or somesuch, but you couldn't say that it doesn't have a fundamental ontology at all.

 

[Canute]

Hmm. I'm struggling with that. It seems inevitable that physics has no fundamental ontology, precisely because it deals only in differences, i.e. with relatives rather than absolutes. We cannot say that a bare difference is a 'thing', so there is no 'thing' for physics to take as fundamental. I thought this was GR's point, that bare differences were not sufficient to explain the universe as we know it through our experience. To be honest I didn't think this view was even contentious, since we've always known that science, or rather, the methods of science, could only deal with (relative) properties and attributes, not with what has those properties and attributes. I thought that GR was using this argument, but relating it specifically to experience. Is this not the case?

 

[hypnagogue]

Hmm. I'm struggling with that. It seems inevitable that physics has no fundamental ontology, precisely because it deals only in differences, i.e. with relatives rather than absolutes. We cannot say that a bare difference is a 'thing', so there is no 'thing' for physics to take as fundamental.

From pg. 32: "Ontology is the study of what exists, with particular emphasis on the different ways different kinds of things exist. Metaphysicians (and scientists) engage in ontology by constructing or endorsing theories about the world, and we usually say that each theory presupposes or has an ontology. A theory's ontology sets out the things whose existence we are committed to if we choose to accept the theory as true."

Following this, we could say a theory's fundamental ontology sets out the fundamental, or non-derivative, things whose existence we are committed to if we choose to accept the theory as true. Physics clearly has a fundamental ontology, then, which includes mass, charge, etc. If we accept physical theory as true, we are committed to believing that mass and charge exist, and also that they are part of the fundamental, irreducible 'furniture' of the world. (Later theories may overturn this and establish something like strings as fundamental, but as long as something is taken to be fundamental, then we have a fundamental ontology.)

That these fundamental things in physics are relational and not intrinsic is a claim about the nature of physics' fundamental ontology, not a claim about its actual existence.

I thought this was GR's point, that bare differences were not sufficient to explain the universe as we know it through our experience.

Yes, that is his point. Any confusions or misgivings you have here seem to be more terminological (how we define 'fundamental ontology') than substantive (what difference this issue actually makes to the argument).

 

[honestrosewater]

Isn't he saying the opposite to this, that there is a difference between 1+2 and 2+3 that depends on the nature of the integers involved, and not just on the relationship between the them?

But as far as arithmetic is concerned, the nature of the rationals (incl. the integers) is only the relationships between them; There is nothing more to them. 0 and 1 can be defined in terms of other rationals (as additive and multiplicative identities) and all other rationals can be defined in terms of 0 and 1. I think that's his point- math (incl. arithmeic) is a "bare difference" structure, and, if I understand "bare difference", I agree. I think his dot structure is supposed to be a bare difference structure as well.
If, as far as the dot structure is concerned, 0 does not equal 0 does not equal 0, then 0000 does not equal 0000 as he says:

For example, one can instantiate the same structure of differences between two other colors whose hues lie at the same distance from each other as red and yellow (e.g., yellow and green). A pattern of dots of these colors will yield a different color from orange. Therefore, we can observe an identical structure of formal difference but different colors.

If, as far as the dot structure is concerned, 0 does equal 0 does equal 0, then the example doesn't show what he says:

The example shows that, even allowing that we start with colors, one cannot reduce some colors to the mere difference structure among other colors.

since the structure didn't start with colors. The colors were only different to the person observing them, never to the structure. So have I missed the point or taken the example too far or what? Are his examples not relevant to his argument at all? BTW I'm not trying to pick all the examples apart, if it seems that way; I actually tried to shake this one off and moved on, but it continued to bother me.
I guess I should hurry up and finish the chapter.

 

[Fliption]

Rosenberg defines what he means by observables at the top of page 20. He argues that we are justified in believing that p-consciousness has qualitative content on the basis of first person observational evidence, so he needs to defend the premise that they are even observable in the first place. (As he mentions, some philosophers find the claim that qualia are observables to be problematic.)

Yes, I'm aware of the definition on page 20. I'm just not sure I understand it. "Observable" seems to mean what I think it means but I don't see any words connecting "observable" to "qualitative content". The text just seems to assume that one leads to the other. Which is why I wasn't sure I was understanding the definition of "observables" because I'm not seeing the necessary connection. Are bare differences not observable?

 

[Canute]

I'm struggling with all of this but would mention one thing, since it relates to what I was trying to clarify earlier. If qualia are observables then consciousness is not qualia (unless one wants to argue that qualia observe themselves). This implies that studying qualia is not studying consciousness, and that to study consciousness we must observe it directly, not just observe qualia. Hence the need to rid oneself of qualia in order to reveal what remains once they've gone. This is why I'm not entirely comfortable with calling consciousness phenomenal-consciousness. It seems to muddy the waters. But this is probably just a side issue here.

 

[Steve Esser]

I don't see how the truth of 1 is clear. I'm not sure how we could ever know exactly what a Life world could produce. In fact, that's the very appeal of the Life world. I'm not saying that I think a Life world does entail facts about consciousness, but where is the proof that it does not? I had the impression in the other thread that Gregg was claiming that a mathematical proof of this does exist. I find myself wondering, though, how that could even be possible. What kind of math can demonstrate either the existence or non-existence of consciousness?

I don't know about proof, but I find the following persuasive:

(p.22)"...our acquaintance with the phenomenal qualities yields information about them as contents occupying slots within these difference structures. Reification of the difference structure as basic ignores the grounding of those difference structures in each specific case and so ignores the content instantiating those structures."

It isn't that the life world couldn't support experience if its difference structure was instantiated in the right stuff. The point is that it is a bare difference structure floating untethered to any content. It is our first person experience which provides the evidence that such a contentful grounding exists in the actual world.

 

[honestrosewater]

I don't know if everyone reads the footnotes, but footnote #5 went the furthest towards clearing up observables for me.

The relevant argument for the premise is (P): If x has the status of being an observable, then the evidence for x must also have the status of being observable. For example...

I can't help but wonder what the difference is between "being an observable" and "being observable".
It could have to do with what I think Canute is asking: If consciousness contains qualitative content, what contains consciousness?

 

[honestrosewater]

The following are all from chapter 2.

A1. Facts about a pure Life world do not entail facts about phenomenal consciousness.
A2. If facts about a pure Life world do not entail facts about phenomenal consciousness, then facts about a pure physical world do not entail facts about phenomenal consciousness.
A3. Therefore, facts about a pure physical world do not entail facts about phenomenal consciousness.

B1. The fundamental properties of a pure Life world consist of bare differences.
B2. Facts about phenomenal consciousness include facts about qualitative content.
B3. Facts about bare differences cannot entail facts about qualitative content.
B4. Therefore, some facts about phenomenal consciousness are not entailed by pure Life facts.

C1. They belong to a type whose members are potential objects of awareness.
C2. We can become aware of them without the aid of special instruments.
C3. The dubitability of our belief in facts of the relevant type is almost zero.
C4. Our awareness of instances of the type is reliable.

D1. Some thoughts and memories are observables.
D2. If thoughts and memories are observables, then the evidence for them is observable.
D3. Phenomenal contents (i.e. qualia) provide evidence for observable kinds of thoughts and memories.
D4. Therefore, qualia are observable.

E1. If x has the status of being an observable, then the evidence for x must also have the status of being observable.

Can someone confirm that the Cs are referring to observables and not to qualia? What makes an instrument special (in C2), and how is the distinction justified? I would guess that special instruments are not capable of detecting qualitative content.

It seems there are three types of worlds here: pure Life worlds, pure physical worlds, and (what I'll call) impure worlds. Can I add

F1. If the evidence for x has the status of being observable, then x is a fact about an impure world.
F2. All instruments in a pure Life world are special instruments.
F3. Some instruments in an impure world are not special instruments. ?

I ask because I think I have discovered what has been missing for me to get from what I think of as the archetypal bare difference structure, math, to his example of a bare difference structure, a pure Life world: instruments. Measurement, detection and observation are done with instruments. If one is going to make a distinction between them (measurement et al), making distinctions between instruments seems like the first place to start. Surely a pure Life world must be able to detect whether a cell is on or off. Rosenberg's conditions for observables (if the Cs did refer to observables) seem to rule out observation in a pure Life world. So what type of instruments does a pure Life world lack? IOW, what is so special about nonspecial instruments, if anything?

I do have a sneaking suspicion that I'm going in the wrong direction (I actually intended to condense his arguments), but all other paths were dead ends. :yuck: I didn't think tying this all together would be so grueling.

 

[hypnagogue]

Yes, I'm aware of the definition on page 20. I'm just not sure I understand it. "Observable" seems to mean what I think it means but I don't see any words connecting "observable" to "qualitative content". The text just seems to assume that one leads to the other. Which is why I wasn't sure I was understanding the definition of "observables" because I'm not seeing the necessary connection. Are bare differences not observable?

The claim isn't that if something is observable, then it must have qualitative content. The definition Rosenberg supplies is consistent with the existence of observables in a pure Life world. For instance, we know that a portion of a Life grid can instantiate a universal Turing machine (pg. 16). Suppose a portion of the grid on a pure Life world is a simple kind of Turing machine T that can detect the presence of gliders. T might have a series of cells that reside inside of it that have two basic states, which we could call 'D' (detected) and 'U' (undetected). Suppose the default state is U. T's internal state flips from U to D if and only if a glider collides with T at the appropriate location. If no other gliders collide with T for a given series of time steps, T changes its state from D back to U.

In a pure Life world that contains Turing machines like T, gliders meet Rosenberg's criteria for an observable.
1. They belong to a type whose members are potential objects of awareness (here, 'awareness' is nothing more than T's internal state which can switch between D and U).
2. Machines like T can become 'aware' of gliders without the aid of special instruments (by definition, T has everything it needs to detect gliders).
3. The dubitability of T's 'belief' in the presence of gliders is almost zero (here 'belief' could just be T's detection of its own internal state; if it detects its internal state is D, in some sense we could say that it 'believes' a glider has just collided with it. T's 'belief' is beyond doubt, because its state only changes to D if a glider has collided with it in the appropriate way.)
4. T's awareness of instances of gliders is reliable (the rules governing a pure Life world's dynamics guarantee that whenever a glider collides with T at the appropriate location, a causal chain is set off that culminates with its internal state being set to D).

So there isn't a necessary connection between X being an observable and X having qualitative content. Rosenberg argues that qualia are observables just to establish that we do indeed have some kind of epistemic access to them. Once he establishes this, he argues that qualia have qualitative content on the basis of what we observe about them, or perhaps more aptly, the very nature of our observations themselves.

First he argues that the differences between families of qualia cannot be understood as mere difference structures. For instance, we know that there is a difference between phenomenally experienced red and blue, but this difference is not observed as mere difference, with no grounding content. It is difference that obtains in virtue of the varying qualitative contents of the two experiences. He goes on to argue that specific qualia themselves-- for instance, just the experience of orange-- cannot be understood as just difference structures, because for any given difference structure we suppose to be phenomenal orange, it is still consistent that this difference structure should be something else, such as phenomenal purple.

 

[loseyourname]

I don't know about proof, but I find the following persuasive:

See, I'm pretty sure he said something about being able to produce a mathematical proof in another thread. He just didn't do it in the book because it would be cumbersome. Does anyone know anything about this?

(p.22)"...our acquaintance with the phenomenal qualities yields information about them as contents occupying slots within these difference structures. Reification of the difference structure as basic ignores the grounding of those difference structures in each specific case and so ignores the content instantiating those structures."

I'm going to have to go back and look at this chapter again. I read it a couple of weeks ago and don't have the book with me. It's hard to evaluate these arguments out of context.

It isn't that the life world couldn't support experience if its difference structure was instantiated in the right stuff. The point is that it is a bare difference structure floating untethered to any content. It is our first person experience which provides the evidence that such a contentful grounding exists in the actual world.

Well, I'm not so sure about that. I think we can say that difference structures need to be instantiated simply because there can't be differences if there aren't things that are different. I don't see why first person acquaintance with an instantiated world is necessary.

It isn't this that I have any objection to, however. I'm just not convinced that the instantiation is necessary to an explanation of experience any more than it is to an explanation of other phenomena with qualitative content. Breathing isn't exactly the best example, but think of such things as novels and paintings. Physics doesn't explain the qualitative content of these kinds of things, but does that mean they couldn't exist in a pure life world?

I guess I'm kind of stuck in a rut here, because I agree with Gregg's argument to the extent that I don't think any world could exist as a pure life world. Even life worlds themselves are instantiated, by the hardware and the programming they require to exist. By this token, I agree that a physical explanation of the world will never be a complete explanation. It seems that every thing that exists has an aspect to it that physics says nothing about. Yet no one criticizes physical explanations of most of these things. I'll reread the chapter and try to state this a little more coherently, probably over the weekend.

 

[Canute]

I have no problem with the author's conclusion in this chapter, that physicalism is false, so I'm happy to move on without too much analysis here. However I do have problems with his arguments. For instance:

B1. The fundamental properties of a pure Life world consist of bare differences.
B2. Facts about phenomenal consciousness include facts about qualitative content.
B3. Facts about bare differences cannot entail facts about qualitative content.
B4. Therefore, some facts about phenomenal consciousness are not entailed by pure Life facts.

From what the author writes I've taken the term 'bare differences' to mean aspects and properties, things which have an epistemilogical existence but which have no ontological existence, differences that do not actually exist in the sense of being 'out there' or physical, but which appear to exist in phenomenal consciousness, in our own experience. They exist only in that they are distinctions made by an observer, but do not exist in any other sense. Red and green, monday and tuesday, sad and happy, perhaps good and evil and so on.

I suppose that in this sense it could be said that a pure Lifeworld is epiphenomenal on nothing, consists of nothing but bare differences, external aspects and appearances. I hope this is a correct interpretation.

If this is then bare differences are equivalent to what mathematician George Spencer-Brown called 'distinctions', 'indications', or 'marks in the void', (and perhaps even what Plato called 'Ideas' or 'Forms'?). Because of this I feel that that GR has hit on exactly the right argument to falsify physicalism, because it challenges physicalists to explain what underlies the bare differences that they normally take to be fundamental, what matter really is underneath its external attributes.

I take 'phenomenal consciousness' to mean 'experience'. So line B2 states that experience has qualitive content. I would rather say that experience is qualatitive content, and not risk assuming that they are separate things.

Line B3 is where I grind to a halt. In many people's view the qualitative content of our normal consciousness consists of no more than bare differences, distinctions which have no inherent existence. That is, bare differences are qualitative content for most purposes. To say that facts about one cannot entail facts about the other doesn't make sense when they may be the same thing.

For the statement to make sense it would be necessary to show that it was not our consciousness that makes the distinctions that are the bare differences which constitute the qualitive contents of our consciousness. Er, that is, it would be necessary to show that what we normally call the contents of our consciousness is not itself just a collection of bare differences.

This would entail proving that what we normally call our world (which includes both mind and matter) is not a pure life world, that it is not just a collection of bare differences, the whole thing epiphenomenal on nothing.

Nobody has ever managed to do this, and many people argue, with one important proviso, that this is exactly what our world is. Unless GR can show that it is not then his argument fails for the same reason that he is arguing physicalism fails. It has an incomplete ontology, and is thus an incomplete metaphysic or cosmology.

I read line B4 as saying that experience must consist of more than bare differences. If this is what he means then I agree (this is the important proviso mentioned above). However I don't feel he makes his case.

 

[hypnagogue]

See, I'm pretty sure he said something about being able to produce a mathematical proof in another thread. He just didn't do it in the book because it would be cumbersome. Does anyone know anything about this?

He mentioned an inductive proof to the effect that a pure Life world could not entail intrinsic properties. Of course, it's a non-trivial further step to claim that phenomenal consciousness has intrinsic properties / qualitative content. I doubt a mathematical proof of that claim would even be possible; Rosenberg argues for it by appealing to first person observation of one's own phenomenal consciousness.

It isn't this that I have any objection to, however. I'm just not convinced that the instantiation is necessary to an explanation of experience any more than it is to an explanation of other phenomena with qualitative content. Breathing isn't exactly the best example, but think of such things as novels and paintings. Physics doesn't explain the qualitative content of these kinds of things, but does that mean they couldn't exist in a pure life world?

What facts about a painting or a novel could physics not entail? An extended discussion of this would be interesting. For now I'll just say that it seems the only things relating to novels or paintings that physics could not entail is just the qualitative experiences of the people perceiving them: the visual quality of a particular grade of colors and the felt emotions of beauty it invokes, or the qualitative sense of meaning that a page in a novel might invoke, etc. So novels and paintings don't seem to add anything above and beyond the already noted problem of qualitative content in p-consciousness.

 

[Fliption]

So there isn't a necessary connection between X being an observable and X having qualitative content. Rosenberg argues that qualia are observables just to establish that we do indeed have some kind of epistemic access to them. Once he establishes this, he argues that qualia have qualitative content on the basis of what we observe about them, or perhaps more aptly, the very nature of our observations themselves.

Ok, I understand. Thanks for the explanation. Now it appears to me that this argument that qualia has qualitative content isn't a whole lot different from other arguments we've heard before (such as the color blind scientists Mary example). Unfortunately, these past arguments have always had rebuttals and I see that this one doesn't seem to be convincing to some of the participants here as well. It still seems as if we're stuck with "it is qualitative because it seems qualitative". Has any progress been made in this regard with this book or are we missing something? I personally agree with the idea. I'm just not sure the arguments in this book are any different or stronger than previous arguments. (I'm referring specifically to the point of qualia being qualitative and therefore not subject to explanation by physics)

 

[hypnagogue]

I can't help but wonder what the difference is between "being an observable" and "being observable".

I don't think there is any substantial difference. It's just more convenient to define something as an observable, as opposed to having to say something like "an observable phenomenon" over and over.

 

[hypnagogue]

Can someone confirm that the Cs are referring to observables and not to qualia?

Yes, the Cs are Rosenberg's defining criteria for what an observable is.

What makes an instrument special (in C2), and how is the distinction justified?

I imagine this refers to, for example, using an electron microscope to view the fine structure of a tissue. To be honest, I'm not sure why it's important to stipulate that an observable meet this condition. It might have something to do with previous philosophical discussions on observables that have found the distinction important for whatever reason.

F1. If the evidence for x has the status of being observable, then x is a fact about an impure world.
F2. All instruments in a pure Life world are special instruments.
F3. Some instruments in an impure world are not special instruments. ?

I have a different interpretation of what Rosenberg means by observables. It seems to me that observables could exist in a pure Life world. See my last response to Fliption's post.

I didn't think tying this all together would be so grueling.

I don't know if this has been a point of confusion for you, but if it helps, all the argument forms you listed are part of one overarching argument. The main argument is what you have listed as As; the Bs are a separate argument in defense of the premise A1; the Cs and Ds are used to argue for premise B2. They are not independent arguments, but rather, they are nested inside of each other.

edit: And just to be perfectly clear... the Cs are not an argument, but a definition.

 

[Canute]

I see now that my last post was not at all clear (as usual). I'll have another go.

I suppose what I was trying to say is that if bare differences have no intrinsic existence then there is only one place that they can exist, in the mind of an observer. Bare differences must be observable for this reason.

But if it is only bare differences that we ever observe, and if it is those observed bare differences that are the qualatitive content of our minds, then both facts about minds and facts about matter reduce to facts about bare differences. It is therefore possible that all facts about the world of physics and all facts about our inner mental world of qualitative differences reduce to facts about the observer. What we cannot reduce to bare differences is the observer, the entity that observes and thus reifies these bare differences, be they 'physical' or mental.

Perhaps this is what GR is saying. But I feel he confuses the issue when he says that the existence of qualitative contents shows that we are not living in a pure Lifeworld. Qualitative differences are not, or may not be, in themselves any more 'real' (ontologically grounded) than any other kind of bare differences. It is simply the existence of these bare differences, regardless of whether they are mental or 'physical', that shows we do not live in a pure Lifeworld, since it shows that in addition to bare differences our world contains an entity that distinguishes between these differences. This makes the argument that mental differences are of a different kind to the bare differences of phsyicalism redundant. They may not be different at all, but the existence of either shows that physicalism is false, since if only bare differences existed then bare differences could not exist. That is, bare differences of any kind imply the existence of something that is not just a bare difference, but which exists in an complete ontological sense.

So while I agree with GR that physicalism is ontologically grounded on bare differences, and thus not ontologically grounded, I find it confusing that he takes the qualatitive content of consciousness as foundational, as showing that there is more to the world than bare differences. It is the very fact that bare differences exist that shows that there is more to this world than bare differences, regardless of whether they are qualitative contents of consciousness or facts about a pure Lifeworld. After all, gliders etc. do not really exist, they are just collections of pixels in an on or off state, they are reified as gliders etc. by an observer.

This is not to contradict the conclusion of his argument, just the way he's made it. The net result is the same, that physicalism has an ontology grounded on bare differences, that we know that there is something that is not a bare difference, and that therefore it must be the case that physicalism leaves something out. (To me this seems to be just the problem of attributes stated in a different form). But I find his argument confusing.

I suppose in a nutshell I don't like the way he reifies the qualitative content of consciousness, rather than consciousness itself. In the end it is the observer, the act of observation, that is outside of the pure Lifeworld, not what is observed, and both the bare differences observed by physicists and the bare differences observed by us that we call qualitative content may well be part of a pure Lifeworld, and be explicable within it. (I.e. mind may be explixable in terms of brain). What is not explicable is the act of observation, the perceiving and conceiving by which those differences are reified by us.

If that makes no sense I apologise, just ignore it. I'm not arguing with his conclusions, so I'm happy to move on. However If I was a physicalist I don't think I'd be convinced by this chapter. Please correct any mistakes. I'm not at all sure yet that I've correctly understood what the author is saying.

 

[hypnagogue]

Ok, I understand. Thanks for the explanation. Now it appears to me that this argument that qualia has qualitative content isn't a whole lot different from other arguments we've heard before (such as the color blind scientists Mary example). Unfortunately, these past arguments have always had rebuttals and I see that this one doesn't seem to be convincing to some of the participants here as well. It still seems as if we're stuck with "it is qualitative because it seems qualitative". Has any progress been made in this regard with this book or are we missing something? I personally agree with the idea. I'm just not sure the arguments in this book are any different or stronger than previous arguments. (I'm referring specifically to the point of qualia being qualitative and therefore not subject to explanation by physics)

Two of the most hotly debated antiphysicalist arguments thus far have been Chalmers' Conceivability Argument and Jackson's Knowledge Argument. These arguments have been motivated by the same general intuitions behind Rosenberg's argument, but there are several important differences.

The Knowledge Argument presents us with Mary, a super neuroscientist brought up in a black and white room. Jackson argued that Mary could know all the physical facts about the brain, but still experience something novel or unexpected upon first seeing a new color, red for example. The intuitive appeal to this argument is strong for most, but some argue that it falls short of falsifying physicalism; others reject the intuition altogether and claim that Mary's complete knowledge of her dispositional reactions upon seeing red (e.g. a verbal report along the lines of "Wow, I never would have expected that it would be like this!") completely account for everything there is to her novel experience.

Chalmers' Conceivability Argument claims that it is logically consistent to imagine a world with an identical physics to ours, in which there are cognitive agents physically identical to humans (zombies) that nonetheless do not have subjective experience. From the conceivability of such a zombie world, Chalmers infers that it is metaphysically possible for a zombie world to exist. He concludes that if a zombie world is metaphysically possible, then physicalism must be false. (If physicalism were true, then a zombie world should be metaphysically impossible.)

Physicalists have not been compelled by the intuition behind these thought experiments, and claim that they are both ultimately nothing more than arguments from failure of imagination. (This counterargument has also been popular for some of the dedicated physicalists here at PF.) A succinct characterization of this stance from the Churchlands is quoted on page 26:

The negative arguments here all exploit the very same theme, viz. our inability to imagine how any possible story about the objective nuts and bolts of neurons could ever explain the inarticulable subjective phenomena at issue.

Rosenberg's argument is impervious to this critique. He does not depend on intuition about hypothetical situations; rather, he mounts a direct attack on physicalism by making observations about the ontology of physicalism and the ontology of p-consciousness, and showing us precisely why it is that the former cannot entail the latter. Rosenberg makes a novel move by doing much of his explanatory work in the context of a pure Life world, which forces us to isolate the relevant problems of physicalism without importing much of our conceptual baggage and biases about it.

So the physicalist cannot brush off Rosenberg's argument as so much unimaginative nonsense, and must directly contend with one of the premises of his argument. But that physicalism is an ontology of bare differences, and that an ontology of bare differences cannot entail qualitative content, seem to be more or less airtight assertions.

In his discussion of the Knowledge Argument on page 23, Rosenberg shows that various physicalists have even already shown implicit support for the premise that bare difference cannot entail qualitative content. Perhaps a physicalist will be sympathetic with the intuition that upon first seeing red, Mary will have learned an unanticipated fact about phenomenal redness, but such a physicalist might deny that this falsifies physicalism, e.g. by claiming that experiencing phenomenal redness is just a new way of comprehending a fact about the brain that Mary already knew. Rosenberg notes that although this physicalist has not yet conceded physicalism, he has certainly acknowledged that Mary's bare difference understanding of the brain was not enough to entail knowing what it is like to experience red. As such, even though this physicalist has not bought into the Knowledge Argument, he has implicitly agreed with an important step in Rosenberg's argument.

The only physicalist response to the Knowledge Argument that will not work in favor of Rosenberg's argument seems to be the claim that Mary's a priori knowledge of how she will behave, what she will say, etc., upon first seeing red comprises everything there is to know about her prospective experience. On this view, Mary alreadys knows everything about what it is like to experience red before having seen it, just from her knowledge of the dynamics of the brain, because there is supposedly nothing more to her experience than the manner in which she will be inclined to react. This is a rather extreme eliminative materialist position held for instance by Dennett.

Ultimately, it seems as if the committed physicalist's only recourse for taking issue with Rosenberg's argument is to deny the premise that consciousness contains qualitative content. Rosenberg goes about as far as he can in defense of this premise, arguing that the physicalist cannot deny qualitative content on the grounds that we do not have epistemic access to qualia. At this point, we have more or less bottomed out in terms of logical argument, and it comes down to first person observation. So this is an empirical claim, but one complicated by problems of epistemic access. Although Rosenberg argues that we have first person epistemic access to experience, we still do not have third person epistemic access to it. We can't exactly plop subjective experience down on a table and say, "See! There it is!" So the physicalist can still deny the empirical claim that experience has qualitative content without fear of being 'proven' wrong, in the sense that we can make empirical claims about objective phenomena and be straightforwardly shown to be wrong via third person demonstration.

The upshot of all this is that, if nothing else, the committed physicalist is painted into a corner. For the physicalist who denies the Knowledge Argument and the Conceivability Argument on the grounds of failure of imagination, there is still room to believe that "the objective nuts and bolts of neurons" somehow account for qualitative subjective experience. Rosenberg takes away this option, however, by directly showing how it is that such an objective account cannot entail qualitative experience.

So, as we saw above with Rosenberg's twist on the Knowledge Argument, the only philosophically tenable position left to the committed physicalist is eliminative materialism, which is a much stronger position than many physicalists would probably like. The eliminative materialist essentially holds that we really are zombies who have somehow been duped into thinking that we are not. For the antiphysicalist, this seems more like biting the bullet in order to cling to a paradigm than an intellectually honest assessment of the phenomena nature presents us with.

Ultimately, Rosenberg seems to have taken this argument about as far as it can be taken, polarizing possible stances on subjective experience in the process. The force of his argument seems to effectively recruit all physicalists who take subjective experience seriously onto the antiphysicalist side, leaving only eliminative materialists to carry the physicalist torch. If that is not complete consensus, it is at least substantial progress.

 

[hypnagogue]

I suppose what I was trying to say is that if bare differences have no intrinsic existence then there is only one place that they can exist, in the mind of an observer. Bare differences must be observable for this reason.

You seem to be operating from the intuition that something like a pure Life world is incoherent, and could not enjoy some kind of existence without some kind of grounding entity (be this qualitative content, or an irreducible experiencer, or whatever). There is something to be said for that stance, and Rosenberg argues for it later on in the book.

However, this concern doesn't really factor into the arguments of this chapter. Physicalism is committed to the claim that all ontology is bare ontology, so in this chapter Rosenberg analyzes what could be entailed from such an ontology, independent of concerns about the internal coherence of the ontology itself. If we stipulate up front that such an ontology can't work, then we can't argue against physicalism on its own terms and the argument loses much of its force.

Here's another way to think of it. In this chapter, Rosenberg is arguing against a conditional claim. If we define
P: The world's ontology is composed of bare differences
Q: The world has qualitative content
then Rosenberg is interested here in arguing against the possibility that the conditional P -> Q could be true, on any construal of the specific natures of those bare differences and qualitative contents. Of course, if we could show P to be false, then the entire conditional must be false as well. But the argument gains more force if we establish that P ^ ~Q must be true-- that is, even granting physicalism's assumption that P is true, we still can't conclude Q.

But if it is only bare differences that we ever observe, and if it is those observed bare differences that are the qualatitive content of our minds, then both facts about minds and facts about matter reduce to facts about bare differences.

That's true, of course, but Rosenberg argues that bare difference is not all we ever observe. There are first person observational grounds for believing that we do not observe bare differences, but differences instantiated by qualitative content.

I suppose in a nutshell I don't like the way he reifies the qualitative content of consciousness, rather than consciousness itself. In the end it is the observer, the act of observation, that is outside of the pure Lifeworld, not what is observed, and both the bare differences observed by physicists and the bare differences observed by us that we call qualitative content may well be part of a pure Lifeworld, and be explicable within it. (I.e. mind may be explixable in terms of brain). What is not explicable is the act of observation, the perceiving and conceiving by which those differences are reified by us.

I believe I can understand your general concern here. Although it may not be explicit in this chapter, Rosenberg's concept of the qualitative content of p-consciousness already includes what you are thinking of as the experiencing subject. He conceives of phenomenal and experiential properties as distinct but also as necessitating each other's existence, somewhat analogous to how we can say the front and back of a wall are distinct, but that the existence of one presupposes the other. This view will be developed substantially and explicitly in the second half of the book.

 

[loseyourname]

The argument is not sufficiently general that we can rephrase it as "if facts about a pure Life world do not entail facts about X, then facts about a pure physical world do not entail facts about X," for any phenomenon X. It should be clear from section 2.5 that the argument gets its traction from consideration of bare differences and qualitative content.

I'm going to reread 2.5 this weekend, but for now I'll point out that the argument only says that if facts about a pure life world do not entail facts about x, then facts about a pure physical world do not entail facts about x. That is exactly what the premise says, and it is false. Maybe that isn't actually the argument he is making, but if so, he should edit that part of his book.

He mentioned an inductive proof to the effect that a pure Life world could not entail intrinsic properties. Of course, it's a non-trivial further step to claim that phenomenal consciousness has intrinsic properties / qualitative content.

It's non-trivial to say that phenomenal consciousness has qualitative content. I don't think it is non-trivial to say that qualitative content is intrinsic.

What facts about a painting or a novel could physics not entail? An extended discussion of this would be interesting. For now I'll just say that it seems the only things relating to novels or paintings that physics could not entail is just the qualitative experiences of the people perceiving them.

I don't think there are any facts about paintings and novels that physics can not entail. I just think there are facts about them which physics has nothing to say about. By the same token, physics can entail social behavior and such, but it doesn't really say anything about it. That's the basic anti-reductionist argument that has really come to forefront of the sciences in recent years. It's one thing to say that physics does not give a complete description of a phenomenon, and another thing entirely to say that physics does not entail that phenomenon. I agree perfectly well that physics will probably never be able to explain the qualitative content of phenomenal consciousness, but it will also never be able to explain social behavior. There are many cases in the biological and social sciences in which a purely quantitative description of something won't tell you everything, and, in such cases, qualitative descriptions are used.

With regards to the novel, physics can never tell us anything about the grammar or narrative structure. Physics can never tell us anything about the historical background or even the meanings of the words. Are you really prepared to say that these things do not exist separate from your experience of them? Could zombies not write novels?

 

[Canute]

Brilliant. That clears everything up for me. You're up there with Colin McGinn for clarity in my opinion. I hope you're working on a book.

My only comment would be to repeat what I think both myself and Honestrosewater have said in different ways above, that all this does not mean that what we usually call qualitative contents, things that the author takes as ontologically fundamental, are not themselves bare differences, nor that they cannot arise in a pure Life world consisting only of bare differences. In other words his argument disposes of physicalism, but leaves open the possibility that we are living in a pure Life world, in a world that can be modeled as a system of bare differences. To show that this is not the case would require further argument.

As Looseyourname says "It's non-trivial to say that phenomenal consciousness has qualitative content. I don't think it is non-trivial to say that qualitative content is intrinsic."

This point doesn't actually prevent his argument against physicalism working in my opinion, but in taking qualtitative contents as fundamental he doesn't half muddy the waters. It's a loose end that perhaps he deals with later.

 

[hypnagogue]

I'm going to reread 2.5 this weekend, but for now I'll point out that the argument only says that if facts about a pure life world do not entail facts about x, then facts about a pure physical world do not entail facts about x. That is exactly what the premise says, and it is false. Maybe that isn't actually the argument he is making, but if so, he should edit that part of his book.

That premise is false, but that is not the argument presented in the book. It explicitly says, "If facts about a pure Life world do not entail facts about phenomenal consciousness, then facts about a pure physical world do not entail facts about phenomenal consciousness." Nowhere is it stated that that premise generalizes for any arbitrary phenomenon, nor is there anything in the content of the argument to imply that it generalizes; quite the contrary.

It's non-trivial to say that phenomenal consciousness has qualitative content. I don't think it is non-trivial to say that qualitative content is intrinsic.

Fair enough, but it seems to me that any construal of the qualitative content of p-consciousness that describes it as not intrinsic is just a variation of eliminative materialism. It seems that any acknowledgment of 'qualitative content' on this view is a rather hollow one that is closer to denying qualitative experience (writing it off as a misguided illusion of some sort) than it is to embracing it as an actually existent phenomenon.

I don't think there are any facts about paintings and novels that physics can not entail. I just think there are facts about them which physics has nothing to say about. By the same token, physics can entail social behavior and such, but it doesn't really say anything about it. That's the basic anti-reductionist argument that has really come to forefront of the sciences in recent years. It's one thing to say that physics does not give a complete description of a phenomenon, and another thing entirely to say that physics does not entail that phenomenon. I agree perfectly well that physics will probably never be able to explain the qualitative content of phenomenal consciousness, but it will also never be able to explain social behavior. There are many cases in the biological and social sciences in which a purely quantitative description of something won't tell you everything, and, in such cases, qualitative descriptions are used.

If a complete physical theory doesn't give a complete description of the objective aspects of social behavior, it is because of difficulties in practice such as intractability, not because of difficulties in principle (at least, according to physicalism). High level accounts of social behavior are certainly more useful for us, but if nothing in the high level account is not entailed by physics, then nothing in the high level account is not completely described by a physical account of the appropriate scope and detail. Starting with a given set of physical facts and all the laws governing their dynamics, there is nothing in the high level social account that we could not calculate (if only in terms of probability) given a sufficiently powerful computer. This physical account already includes phenomena such as the thought processes of a social anthropologist as he sits at a computer typing a paper about social behavior. Ultimately everything seems accounted for, including humans' perspectives on what social behavior is, how it should be conducted, etc.

The antiphysicalist argument is that physics could not completely account for the facts about p-consciousness, even in principle. That's a much stronger claim than, and a claim of an entirely different nature from, the claim that physics can't completely describe social behavior, as you have cast it above. The latter is not a threat to physicalism, but the former is.

With regards to the novel, physics can never tell us anything about the grammar or narrative structure.

Physics can tell us everything about the brains of humans, in which concepts such as grammar and narrative structure reside. Since grammar and narrative structure are human inventions, I see nothing omitted from the complete physical account, even if it would have to be a rather enormous and messy one.

Physics can never tell us anything about the historical background or even the meanings of the words.

My response is the same as above. So long as the base of given physical facts is expansive enough, and so long as we know all the laws governing physical behavior, historical background and meaning will fall out of the equations. Meaning is a bit trickier because we have subjectively experienced emotion(s) corresponding to meaning. From a physical account, we could figure out things such as what concepts a given word picks out, although in accordance with the antiphysicalist argument, I do not believe we could figure out what it feels like to feel as if something is meaningful.

Are you really prepared to say that these things do not exist separate from your experience of them? Could zombies not write novels?

Of course zombies could write novels; that's the whole point. If zombies could not write novels, then there would indeed be something about novels that is fundamentally elusive to the physical account. But as it follows straightforwardly from the definition of zombie that this is not the case, it is also not the case that there is something about novels that physics could not entail, above and beyond the subjective experiences of those who have written or read the novel.

 

[Canute]

Hypnagogue

The above was written before I read your reponse to my earlier post. I must have missed it somehow. Just to be clear a couple of comments.

You seem to be operating from the intuition that something like a pure Life world is incoherent, and could not enjoy some kind of existence without some kind of grounding entity (be this qualitative content, or an irreducible experiencer, or whatever).

No, I was saying exactly what you say below, that unless he can show that this intuition is incoherent his argument is little weak, only saying it less clearly. I agree with the rest except this.

Here's another way to think of it. In this chapter, Rosenberg is arguing against a conditional claim. If we define

P: The world's ontology is composed of bare differences
Q: The world has qualitative content

then Rosenberg is interested here in arguing against the possibility that the conditional P -> Q could be true, on any construal of the specific natures of those bare differences and qualitative contents. Of course, if we could show P to be false, then the entire conditional must be false as well. But the argument gains more force if we establish that P ^ ~Q must be true-- that is, even granting physicalism's assumption that P is true, we still can't conclude Q.

I think the point being made here by a couple of us is that he has not shown Q -> ~P. He assumes it. He therefore leaves it as possible that both P and Q may be true statements.

As you say above this seems to imply eliminative materialism, but this is not the only option.