He raises the question in the New York Times Sunday Review:
I believe a major change in our perspective on consciousness may be necessary, a shift from a credulous and egocentric viewpoint to a skeptical and slightly disconcerting one: namely, that we don’t actually have inner feelings in the way most of us think we do…
How does the brain go beyond processing information to become subjectively aware of information? The answer is: It doesn’t. The brain has arrived at a conclusion that is not correct. When we introspect and seem to find that ghostly thing — awareness, consciousness, the way green looks or pain feels — our cognitive machinery is accessing internal models and those models are providing information that is wrong…
You might object that this is a paradox. If awareness is an erroneous impression, isn’t it still an impression? And isn’t an impression a form of awareness?
But the argument here is that there is no subjective impression; there is only information in a data-processing device. When we look at a red apple, the brain computes information about color. It also computes information about the self and about a (physically incoherent) property of subjective experience. The brain’s cognitive machinery accesses that interlinked information and derives several conclusions: There is a self, a me; there is a red thing nearby; there is such a thing as subjective experience; and I have an experience of that red thing. Cognition is captive to those internal models. Such a brain would inescapably conclude it has subjective experience.
I agree that our intuitions about consciousness are likely to be faulty, but I don’t think that Graziano has resolved the paradox he mentions. My brain models other people as having subjective experiences, but this obviously has no bearing on whether they really do, or don’t, have those experiences. Given that, why should the fact that my brain models me as having subjective experiences suddenly become magically relevant to the question of whether I really do, or don’t, have those experiences?
Bruce:
Bruce,
That argument doesn’t work against property dualism. Under property dualism, there is a physical difference between the two worlds. In our world, matter has a special property that gives rise to subjective experience. In the zombie world, matter lacks that property. A difference in matter is a physical difference.
That’s why I consider property dualism to be a form of physicalism.
Never mind. I found it myself.
So, are you now saying you’ve been talking about physical possibility throughout–or do we want to stick with your claim that your problem was redundancy?
walto,
We were talking about two separate phrases: “metaphysically possible” and “possible in some worlds”. The first one refers to metaphysical possibility. That’s why the word “metaphysically” appears in it. The second one doesn’t. That’s why the word “metaphysically” doesn’t appear in it.
ETA: That should read:
We were talking about two separate phrases: “metaphysically possible” and “possible in some worlds”. ‘Possible’ in the first one refers to metaphysical possibility. That’s why the word “metaphysically” appears before it. “Possible’ in the second one doesn’t refer to metaphysical possibility. That’s why the word “metaphysically” doesn’t appear before it.
You claimed that “possible in some worlds” doesn’t make sense. That’s wrong, as I explained above. It makes perfect sense, and the Chalmers quote explains why.
You were wrong, you lied, and you deleted a comment.
Now that we’ve established your bona fides, can we please get back to discussing Graziano’s ideas about consciousness?
keiths,
You could consider PD a form of physicalism if you like, but property dualists do not. They emphasize that the property missing in the ZW is a *non*-physical property, thus there are both physical and non-physical properties in our world, and the non-physical properties are responsible for conscious experience.
Oy. I see you’ve switched to the non-redundancy thesis. That doesn’t work either, but I’m too lazy to continue this nonsense.
Oh btw, you didn’t mention your own bona-fides: Nuts, and not actually that bright.
ETA: What I really wish for is that I had some hyper-links in here. Your own posts show that those things are always dispositive, even if they are linked to red herrings and other nuts stuff.
Phooey.
Right;
So I google and I can get pleas in favour of property dualism and pleas against property dualism. What I can’t get is any sense of the usefulness of the idea – its explanatory value. Plus the language is so arcane it is difficult for me to tell whether various discussants are in favour or against various propositions. (I don’t include the SEP author in this; s/he is commendably clear). For instance in this paper (PDF but not huge) Jeff Speaks quotes Saul Kripke on the mind-body “problem” and I can neither tell whether Speaks is for or against some version of dualism nor the does the quote from Kripke make much sense, so I’m guessing he is some sort of dualist.
But wait! This looks like it is written for clarity. The author seems kosher
Hi Lionkitty. How does that work?
Hard science types generally frown on property dualism, because it doesn’t seem to allow for the type-type correspondences needed for neurophysiological approaches and AI production of consciousness. Property dualism theories tend to be token-token claims, following from Davidson’s famous paper. I’m attracted to it myself, but it’s no damn good for anything. It’s just a kind of mysterianism, really.
What do you think of Josh May’s analysis:
I, on little acquaintance, agree strongly with “dualism is unscientific.”
I generally agree, although the property dualism issue is relevant. Anomalous monists are still, by their lights, well, monists.
Alan Fox,
So we’re starting with the notion of Philosophical Zombies, right? And zombies are “molecule for molecule” physical duplicates of human beings who have no conscious experience. It’s “all dark inside” for a zombie.
If the idea of a zombie makes sense to you, then you’re part of the way towards becoming a Property Dualist (no offense intended if you don’t want to be a PDist!).
To actually be a PDist, you’d have say that the *reason* we can have non-conscious Zombie duplicates is that there are more properties in our world than those that exist in the Zombie world, and it’s those extra properties in our world that make us conscious and leave the Zombies bereft.
So, the PDist is (1) comfortable with the idea of a “non-physical property” in addition to all the physical properties in the world, *and* (2) believes that the non-physical properties of the mind neither reduce to nor supervene upon physical properties.
If you’re okay with both (1) and (2), then you can be a property dualist! I’m not a property dualist myself, but I’ve studied the position a bit. I wrote this : https://www.academia.edu/3684747/Inconceivable_Minds and saw someone mentioned it in the thread earlier, which caught my attention!
Must the property dualist be prohibited from claiming that the non-physical properties supervene upon the physical properties? What definition of “supervenience” are you thinking of here? (Sadly, there are a ton of them….)
ETA: BTW, as a N.Cal person you must have seen the portrait of my hero, E.W. Hall a lot. Any chance you could cop that picture for me?? (I’ve mentioned to Lycan his duty to amend his SEP article on representation to include his predecessor as Kenan Prof. He’s promised to do so, but if–while you’re getting that portrait for me–you could see to that issue too, I’d be much obliged.)
Hi Lionkitty,
Welcome to TSZ! I’ve read portions of your dissertation and have a PDF on my Kindle for future reference. It’s a great resource — very well-written and comprehensive.
Wouldn’t you consider nonreductive physicalists to be a species of property dualist? If not, what distinctions would you draw between them?
I think Josh May uses Ockham’s razor wrong. Ockham’s razor is used to find the most parsimonious explanation from among multiple alternatives, not to cut away all explanations. Isn’t the debate over how conscious experience can be there at all on the physicalist assumption? Physicalism cannot explain it. Dualism can. You may not like the explanation, but it’s fallacious to appeal to Ockham’s razor to eliminate the explanation and be left with no explanation.
walto,
No, I haven’t. “Metaphysically possible” and “possible in some worlds” are redundant, but in the second phrase, the word “possible” does not mean “metaphysically possible”. It is the whole phrase, not the single word, that is redundant with respect to “metaphysically possible”.
But since you’re never going to admit that you’re wrong, that you lied, and that you deliberately deleted your comment, let’s drop it and focus on discussing consciousness.
Hi Walto-
Sorry to disappoint you about the Hall photo, but the UNC where I spent my time was in North Carolina, not Northern Cal. But oh my that would have been fun!
You’re right about supervenience- there are tons of types. It seems that the most popular PD view holds that non-physical (“phenomenal”) properties *naturally* supervene on physical properties- that is, given the laws of nature in our world, there can be no change in phenomenal properties without a change in some physical property(s). So any possible world that has all our “natural” laws (for lack of a better term!) has consciousness in it.
But according to PD there are *metaphysically* possible worlds (W1) that are physically just like ours (W) but have different “psycho-physical laws” such that whatever physical properties (PR) the “sensation of red” supervenes upon in W, the “sensation of blue” supervenes upon those physical properties (PR) in that other metaphysically possible world. And there are still other metaphysically possible worlds in which there are no “psycho-physical” laws at all- no laws governing the supervenience of phenomenal properties on physical properties. Those worlds have no phenomenal properties- they’re zombie worlds.
So the kind of supervenience that’s at issue is “metaphysical supervenience” (or perhaps “logical supervenience”- it’s unclear whether those two notions are taken to amount to the same thing or are distinct), rather than “physical supervenience”. PDists, by and large, don’t think anyone could be a “philosophical zombie” in our actual world.
My apologies in advance if I suddenly stop posting- work is calling to me! Thanks for the fun discussion!
keiths,
Thank you so much- that’s very kind, and I’m glad it’s been a good resource for you.
The distinction I would draw between non-reductive physicalism and property dualism is that N-RP holds that the mental metaphysically (or logically, perhaps) supervenes on the physical- in all metaphysically possible worlds, if there are creatures physically identical to human beings (in conditions conducive to life, etc., etc.,) those creatures will have conscious experience just like we do.
PDists, on the other hand, think that in metaphysically possible worlds that contain all and only the physical properties of our world, there would be no consciousness. PDists think that it’s metaphysically *possible* for a creature physically identical to you to lack consciousness. N-RPists think that it’s metaphysically *impossible* for any creature physically identical to you to lack consciousness. Perhaps we should think of mental properties on the N-RP picture as higher-level physical properties… I’m not sure exactly the best way to characterize the difference beyond what each takes to be metaphysically possible/impossible.
I apologize if I drop off the message board suddenly- work is calling and I may have to disappear. Thank you for the welcome and the stimulating conversation!
Thanks for your interesting comments. I’d like to think about them, but my initial response is: Couldn’t there be anomalous monist types who believe that the physical and mental properties are necessarily connected, though not reducible one to the other? For such a one, it’s not that the physical properties CAUSE the mental properties–and so could result in different ones (or none) based on the physical laws in the various worlds: the relationship would be more intimate. I take it that such a view might be useless for science, since I don’t know how any type-type correspondences could be discovered. But I don’t see how the position, mysterian or not, of one event, having both (irreducibly) mental and physical properties, with the type of necessary supervenience you discuss above can be automatically ruled out. (I’m likely missing something, though.)
Regarding Hall, he was indeed Chairman of the Dept. at UNC in the 50s. (I mistakenly typed “N. Cal.” There’s a poster here whom I won’t name, who will claim that I must have been lying when I did that, and that I’m lying now when I say I made a mistake.) Hall held the same Kenan Chair that I think Lycan now holds. (I’ve written a book on the guy: http://www.amazon.com/The-Roots-Representationism-Introduction-Everett/dp/3659484350) Anyhow, now that that’s straightened out, you’re back on board for GETTING ME THAT PORTRAIT! Thanks in advance! 🙂
ETA: I see from your response to keiths above that you may refer to position I’m asking about in my post (or maybe something similar) with the name “non-reductive physicalism.” I’m not sure what position either of you are singling out by that term. Does it countenance mental properties? (If so, why isn’t it a kind of property dualism, and if not, what can’t be reduced to what?) Thanks.
Please let’s all move on.
No, the idea of “philosophical zombies” makes absolutely no sense to me at all.
Currently, there are no adequate explanations for some obvious facts. Humans are here on Earth (along with a plethora of related species). How life got started on Earth is a mystery. I’ll agree that Ockham’s razor doesn’t help here.
Well, you may be unsurprised to find I disagree. Dualism is a kind of defeatism or comfort blanket against the scary “I don’t know” conclusion. Regarding consciousness, there is so much to explore about the reality of how organisms function, to say we don’t have an adequate explanation of something today is no reason to dive off into invention of imaginary essences.
I can live with “we don’t have an explanation for this yet”. It’s no reason to invent one.
Sorry Alan, but if you’re going to let this guy keep calling me a liar, even though that claim is silly on its face, there’s no way I can prove he’s full of shit on that matter, so I’m going to have to keep showing that he’s confused as well as inconsistent about the actual issue. (Although I happily admit that this issue– that the expression “Possible in some worlds” is, when we’re discussing metaphysical possibility [which we were] is a confused locution–is of very very limited interest and has only been kept alive here by keiths’ weird inability to admit that he might ever be confused about something he’s spouted.)
So. Here’s what he wrote, you know, before.
Now, however, he says:
in the second phrase, the word “possible” does not mean “metaphysically possible”.
So, the question is, how can
Metaphysically Possible
and
Possible in some worlds
be equivalent if “Possible” DOESN’T refer to metaphysical possibility in the second one. In particular, as keiths NOW claims (occasionally) that he was really talking about physical or some other non-metaphysical possibility when he wrote “possible in some worlds” one wonders how can it be that the two expressions are equivalent?
As I have said, both in my posts and in my “secret, lying, and then secretly deleted and lied about” posts, if the two expressions are–as keiths once claimed–equivalent, then the expression “possible in some worlds” makes no sense, because metaphysical possibility is not world-relative. If they’re thought not to be equivalent there are, IIRC, some other problems with what he’s written in this thread, but as he’s clearly claimed they ARE equivalent, and I’m sooooo tired of this pointless nonsense, I guess I’ll stop here.
PS: Incidentally, keiths, I think it’s pretty clear to everyone who’s suffered through this thread who has actually been doing all the lying–not just about this silly matter of what “possible in some worlds” means, but regarding a certain charge you made regarding qualia, which I’m also too lazy to repeat. You’re almost at the compulsive stage.
walto,
Read it again.
Erik,
I don’t think substance dualism or property dualism can explain subjective experience. Each is just a promissory note for a particular kind of future explanation.
Substance dualism doesn’t work as an explanation because it simply assumes that immaterial soul-stuff is conscious without explaining how or why. (It also doesn’t work for many other reasons.) Property dualism doesn’t work either because no one can explain (yet, anyway) what the posited extra property of matter is or how it gives rise to mental phenomena.
That’s partly why I’m dissatisfied with my own epiphenomenalism. Mindful of Ockham, I would much prefer a more parsimonious, non-epiphenomenalist, physicalist explanation of subjective experience. The problem is that I’m not yet convinced that these can explain the “subjective” part of “subjective experience”. (Graziano’s solution, of course, is that there is no subjective experience to explain.)
Lionkitty,
It has. Have you considered developing it into a book?
From the rest of your comment, I gather that for you the difference between non-reductive physicalists and property dualists boils down to their beliefs regarding the metaphysical possibility of zombies. N-RPists deny it and PDists affirm it. Is that a fair capsule summary?
I’ll admit to some reluctance to accept a merely metaphysical possibility as the distinguishing characteristic. I may not be alone in my reluctance, as the Wikipedia article on property dualism lists non-reductive physicalism as a type of property dualism:
Lionkitty:
Not to worry. We understand that people have lives outside of TSZ. Feel free to join us again when you have the time and interest.
To tell that it’s immaterial is an explanation because immaterial is exactly how it looks like, and this is how we should start: by accepting the way it looks like. Material is explained precisely the same way: looks like that, therefore it is that.
Property dualism may not work as an explanation for the purposes of physics, but what if the assumption that everything should work so that physics can study it is mistaken anyway? What if metaphysics is real? For example, I don’t know of any fundamental why questions that physics can answer. Metaphysics can.
I’ll echo Keith’s compliments on the clarity and helpfulness of the introductory sections of your thesis and its overview of the positions in the debate on the Zombie argument. (I have not attempted the meat of your work yet).
I do have two quick questions:
1. Did anyone complain about the humor in the section titles?
2. What happened to the parrot when you moved to Canada?
HI Keith:
I think that is not the standard way of looking at physicalism. My understanding is that physicalism restricts itself to the physical properties in current physics and does not include the additional mental properties that Chalmers thinks are needed.
This from SEP: “Similarly, one might say that, in the case of physicalism, no two possible worlds can be identical in their physical properties but differ, somewhere, in their mental, social or biological properties. “.
The implication being mental properties are physical properties, not something separate. I’ve seen the picture in the Wiki article on property dualism, so I can also say that my understanding of physicalism is that the mental properties bubble is not part of the definition of physicalism.
So of course I agree that the argument I posted does not exclude property dualism. In fact, I understand the whole point of the argument is to show that physicalism as I understand it is false and something more is needed, like the mental properties of property dualism.
My understanding is that non-reductive physicalism includes not only property dualism but also other approaches like bare supervienience physicalism, a more restricted version of that called realization physicalism, anomalous monism. There is a Wiki summary. SEP is better I imagine but I have not looked for the best link there.
This does depend on one not using Keith’s definition of “physicalism” where he seems to include the mental properties of property dualism as part of physicalism. I think that is non-standard. I certainly read the literature and in particular LK’s posts here as using my understanding of physicalism.
On a related note, I believe AMs 98 paper on A Non-Reductive Solution to Mental Causation is an attempt to preserve functionalist approaches to NRP from Kim’s attack on it based on the causal impotence of the mental properties it relies on. I understand functionalism for physicalists as being the realization form of NRP.
I’m going to do a longer reply to Keith on this.
(BTW, as far as I know, few pay much attention to Davidson’s anomalous monism these days. The received view of philosophers seems to be realization approaches to NRP. However, reductionism of mental types to brain types is holding its own and possibly making a come back).
Keith:
First, my comments here are based on what I understand as the usual definition of physicalism, as per my previous post to you.
Given that, there are other non-reductive forms of physicalism (NRP), such as realization physicalism which is often what functionalists who are physicalists will rely on. Your quote from Wiki says most PD’s are NRPs, not the reverse. I believe most NRPs are NOT PD’s.
Often the argument of non-PD NRPs is that mental TYPES are not reducible to brain types, even though mental TOKENS are realized through brain tokens. (There are a lot of similarities here, I think, to our discussion of whether bridge laws exist at the other thread. That is, roughly, bridge laws would be what is needed for type-type reduction.)
Let me try to make my understanding clearer by putting it in IT terms. I am sure that by doing so I am losing a lot of the subtleties of the philosophy, but hopefully I keep enough to get the basic ideas right.
Suppose for this explanation that Good Old Fashion AI turns out to be true, that the mind is simply a software program running on the brain, and that furthermore cognitive scientists have reverse-engineered that program into a single-threaded C program (!). So the mind is a C program which could run on the brain or on a digital computer. I know it’s ridiculously far from reality. But let me go with that.
Now for the following I understand “types” to be individuals or properties (that is, n-ary relations on individuals) and “tokens” to be specific values of either of these at some time t.
C Program has types: Variables (including unnamed temps), Statements, Functions, Function Return Info
C Program has tokens: specific values of all variables, and the “program counter for statements”, return values for active functions (at some time t)
Brain has types: neurons, firing rate, connection relation of any two neurons with three values: none, inhibiting, exciting
Brain has tokens: firing rate of neurons, current connectivity, current status of connectivity (at time t)
Digital computer has types: gates, on/off status of gate, connectivity of gate
Digital computer has tokens: list of gates and their status, list of connections (same for all times, btw) at time t. I know I’ve screwed up the hardware stuff, I’m a software guy, so please don’t hold it against me.
The types of the C program are multiply-realized and so cannot be reducible to the types of the computer or brain. But still, their causal powers for a particular realization originate in some sense from the physical substrate of that realization. This is one form of NRP that is not PD.
Thanks, that’s a helpful summary. My allusions to Davidson likely show both (i) my age, and (ii) that I took a break from philosophy for a significant period. So is nice to have people not only link relevant articles but also slip me their own synopses of what happened during Rip Van Hornikle’s nappie.
If by “AM” above you meant A. Thomasson, that’s not precisely how I’ve understood that paper: I should have another look. keiths said he was planning to start a thread on it, so that might be an opportunity.
Re: type-type identity, in my experience, hard headed philosopher types (no pun intended) have always been fiercely supportive. Physicalism seems to them just another meaningless, almost mystical position without it. I’ve been pounded on several forums for suggesting the plausibility of property dualism. It (and Chalmers generally) is a non-starter among the scientistic.
That’s how I understand these classifications, and why your response to me above helps remove some of my befuddlement at the keiths–lionkitty exchange. The suggestion that there’s a third option available that’s not of the useless (if appealing) anomalously monistic kind is something I’d like to look into and think about further (though I have to admit that I’m skeptical: for good or ill, there tends not to be too many genuinely new approaches under the sun).
FWIW, I’m sympathetic with much of this post. First, I think we have to start somewhere, and when we’re trying to explain consciousness, eliminative approaches–those that suggest it doesn’t actually exist seem to me pointless.
Second, I agree that metaphysics is not replaceable by science, although I don’t agree that metaphysics can answer any “why” questions, and I think that when there are actual (and not confused) conflicts, metaphysics must always defer.
Here’s a bad analogy: Putting something to cool outside your window is but also isn’t replaceable by indoor refrigeration. I mean the latter is better for nearly all purposes, but that doesn’t make them the same thing.
[Hey, I already admitted it was crappy. x( ]
Yes, AT not AM; sorry about that.
AT does refer to functionalism and realization in several places in her paper. If her argument works at all, (and Kim does not seem to have changed his mind!), the argument might also work for plain supervenience version of NRP too. I’ve not worked through the subtleties of how plain supervenience differs from realization supervenience. I should probably do that.
I don’t think anomalous monism needs her argument since it starts off with its own sui generis form of mental causation, as I recall. But as a true-blue physicalist , AM always seemed like a copout to me.
I suppose PD may turn out to be true. Call me scientistic, but I think there is a lot more research to be done based on current physics before something has to be added that does not appear anywhere but in consciousness.
If they had to accept PD instead, then maybe physicalist philosophers would hold their nose and accept type-type reduction of psychological, mental events to neuroscientific, brain events. But I don’t think the majority of non-PD philosophers take that route.
The undergrad phil of mind texts I’ve looked at cover the history like this:
1. Cartesian substance dualism: humbug.
2. Behaviorism: Won’t cut it.
3. Place et al identity (type-type) theory: sounds interesting until Putnam and Fodor bring up multiple realizability (after all octopi have pain too, you know!).
4. OK, what about realization functionalism then? Hey, and its NRP too, so we don’t need to get in bed with those nasty all-out reductionists!
Well, there are problems there too in that functionalism seems to allow for any physical realization that has the right causal powers — wouldn’t a nation of people with cell phones and simulating neurons to do the trick? (Block’s Chinese brain argument). But we’ll live with that because, well, multiple realizability, you know …
However, Bechtel (linked in previous posts) and others argue that MR is more of a problem for philosophers and does not trouble scientists. Details in the paper.
I find the most attractive theories involve some kind of psycho-neural identity: specifying the psychological properties at the same level of detail as the neural ones then using psychological types to describe the context of a person’s behavior and neural types in a mechanism to provide a “lower-level’ (in Bechtel’s sense) explanation.
As for PD, I don’t think zombie arguments are the main reason people turn to it. Instead, color-based arguments seem to be tougher to deal with. There is Mary the color-deprived know-it-all scientist in Jackson’s knowledge argument (even though he no longer believes in it). And there are attempts to create spectrum inversion arguments which are still compatible with the scientific explanation of color perception.
One of Kim’s last books was called Physicalism or Something Near Enough because he still thinks such spectrum inversion arguments for physically identical people are possible and evade a scientific explanation (since there is no objective causal difference in such inversions so they are outside of science.)
Now you understand why a color direct perception post would be interesting!
Maybe someday.
Sure, that would be great, although these comments of mine are just a running joke as I am sure you know.
I believe John Campbell works in the philosophy of color perception. I watched a YouTube video of his Berkeley course on Phil of Mind from him once.
He spent a lecture or so talking about color perception and contrasting his views with the standard scientific picture. I found it incomprehensible at that time. I think I’ll try watching it again.
I am not sure what you mean by eliminate, but there are whole industries of neuroscientists and philosophers who accept first hand experience and then try to explain it, not eliminate it.
Of course, part of that explanation has to be be why introspection does not reveal the workings of conscious awareness. So if you mean eliminate theories of consciousness based solely on introspection in one’s favorite armchair, well, then I am all for that.
BTW, thanks for digging up the Yablo paper. I’ll add it to the queue.
By ‘explain’ I don’t mean eliminate. Also, I hope I didn’t say anything that suggested the desireability of eliminating THEORIES of consciousness!
I take an eliminative theory to conclude that there was never any such thing as consciousness to begin with.
FWIW, I think the Buddha may have taken such a position–somaybe I shouldn’t say that claim is silly. He was a pretty smart guy!
Can I sneak in a question on modal logic: if you’ve taught a course on logic, do you have a recommended intro text, especially one that has good coverage of modal logic?
The last time you and Keith had a “discussion” on modal logic (Plantinga…), I found this series of YT videos to help understand the concepts. The series is pretty good, eg a nice discussion of Kripke’s formalization, but I prefer to have texts to read. Nothing useful I could see via Mr Google.
(The only eliminative stuff I’ve looked at is Churchland’s work, and I took it as more about eliminating folk psychological concepts like belief, not consciousness experience per se.)
I taught Intro to Logic once many years ago–but it did not have a modal logic segment. (It was Copi, _Symbolic Logic, which was very good, but I dunno if anybody ever added a chapter on modal logic to it.)
I think nearly everybody who does teach modal logic uses Hughes and Cresswell, (or used to) but I don’t have that book myself, so I can’t really recommend it. You should really ask Lionkitty–who just got through with grad school.
ETA: I haven’t liked anything I’ve read by either of the Churchlands. One of the reasons I admire Thomasson, is that she explains the importance of folk theories (manifest image) and its consistency with science in spite of apparent conflicts. I think KN studied with one of the Churchlands himself, but I guess he’s now off somewhere rereading Adorno.
ETA: Just remember
◊P כ□◊P
That’s another way of saying that nothing is possible (only) in some worlds.
BTW (& OT), I taught a little opening segment on logic in my Intro to Ethics class this semester, and it went really badly. The class was completely stymied by the concept of a truth table, and many of them never caught on. Prolly mostly my fault, but they COULD NOT GET the point of them.
walto,
Talking of folk theories, one of the things that makes me suspicious of folk psychology, is that I learned about it from philosophy books rather than from the folk.
It’s true that philosophers can get that wrong–as well as anything else they write about (just like non-philosophers). You just get madder at them for some reason.
It puzzled me why Wikipedia could call PDs NRPs — in what sense were PDs physicalist.? However, upon closer reading of the Wiki section, I see that Widi only says PDs can be token physicalists, not supervenience physicalists.
As the article explains, the two are different. Supervenience physicalists say that there is no change in mental properties without a change in physical properties. There are only physical properties.
Token physicalists say that there is a physical state with physical properties corresponding to every mental state. But that does not mean that a change in mental state requires a change in physical properties. Its possible to add separate mental properties so that the physical properties stay the same and the separate set of mental properties change. And that is just what PD says.
So PD is only an NPR in the token physicalism sense, not in the standard supervenience physicalism sense.
I think PDs believe in separate mental properties in the actual world, since they agree (with most of us) that this is not a zombie world.
Keith: My understanding is that PDs like Chalmers see that as a job for science.
In a sense, the work on quantum chromodynamics would have seemed like property dualism to 19th century physicists. For them, matter only had gravitational and electromagnetic properties: mass and charge.
But to explain the workings of the nucleus, new properties were added to matter like color charge.
Similarly, PDs think we need to add mental properties to matter to explain consciousness.
Of course, the difference is that physicists had scientific observations and experiments as a reason to introduce new properties for matter, whereas PDs only have armchair thought experiments and intuitions about an explanatory gap.
I would deny that there are mental states.
There is brain activity.
A computer has states. Sets of settings that can be recorded and reproduced. One can re-run the program and get the same sequence of states.
Brains are rivers. Or perhaps flames. They are a flow of process that cannot be recorded and which will never repeat.
Bruce,
Sorry for the delay in responding. I’ve been off having fun with the UDers.
I think it’s saying that all N-RPs are PDs:
It says that N-RP is the predominant form of PD, which means that there are other forms of PD. In other words, N-RP is a proper subset of PD. (Whether you agree with that statement is another question, but the meaning seems clear to me.)
Anyway, I don’t think the distinction matters for the purposes of this thread. I would be quite happy with a fully reductive physicalism if it could explain subjective experience. But like you (if I’m interpreting you correctly), I don’t see how it can. Graziano’s theory is a nice third-person explanation of the observables, but it doesn’t seem adequate as an explanation of subjectivity.
In other words, while I can buy that the contents of subjective experience are illusory, I have trouble with the idea that the illusion itself does not have a subjective aspect.
So my (quite tentative and provisional) position is that subjective experience cannot be reduced to physical properties, though I hope that it will be someday. (Everything else, including mental properties, seems reducible to me).
Rejecting reductive physicalism as an explanation of subjective experience obviously requires something else, whatever we choose to call it.
keiths, to Erik:
Bruce:
Yes, and so do I. I was disagreeing with Erik’s claim that dualism explains consciousness. PD doesn’t explain consciousness; it’s a placeholder for a scientific explanation that we don’t have yet.
walto,
No, the Buddha didn’t deny consciousness. He actually proposed a pretty elaborate ontology of it.