Also, I believe p-zombies can lie, just as some future robot/AI might. That is, they can say something that contradicts their own beliefs for some instrumental aim. This is all cognitive, none of it depends on consciousness.

Maybe not. I was thinking of the case of a p-zombie living among humans. — hypericin

The premise is a world of p-zombies physically identical to us, but with no consciousness anywhere.

Do you think they would have beliefs and knowledge?
— RogueAI
I think so. I think these are cognitive, not dependent on subjectivity. — hypericin

I think hypericin in right. Otherwise, we would have to assume a p-zombie could successfully navigate the world and do all sorts of complex jobs without having any knowledge. The concept of p-zombie researchers exploring the frontiers of science without having any knowledge is incoherent.

Even though it may appear I am taking a position here, I am not at all. I am explaining the concept which has not been understood.

A philosophical zombie or p-zombie is a hypothetical entity that looks and behaves exactly like a human (often stipulated to be atom-by-atom identical to a human) but is not actually conscious: they are often said to lack phenomenal consciousness. — https://www.lesswrong.com/tag/zombies

Being that a belief is a conscious process, a p-zombie would not have beliefs.
A p-zombie is a machine, that acts the way it does, to abuse a Descartes quote, "because of the organised disposition of its organs".

belief is a conscious process — Lionino

5 minutes ago you believed the earth was round, but had no conscious awareness of this belief.

5 minutes ago you believed the earth was round, but had no conscious awareness of this belief. — hypericin

I chuckled when reading this, but not in a condescending way, it reminds me of "The game" or "You are now breating manually" of 2000s internet.

Andrew M. Colman dictionary of psychology defines belief as "Any *proposition (1) that is accepted as true on the basis of inconclusive evidence.

Ted Honderich companion to philosophy as "A mental state, representational in character, taking a proposition (either true or false) as its content and involved, together with motivational factors, in the direction and control of voluntary behaviour."

Simon Blackburn dictionary of philosophy as "To believe a proposition is to hold it to be true".

All published by Oxford, bold is mine.

What you refer to as cognitive seems to mean neurological, which can be explained mechanistically. To believe something invokes a mind. Without a mind, no belief, unless you are reductionist. If you are an eliminativist, there is indeed no belief, and that is fine (but then all of us are p-zombies, and consciousness is an illusion).

The concept of p-zombie researchers exploring the frontiers of science without having any knowledge is incoherent. — RogueAI

Are you being literal with your use of the term “incoherent”? Because prima facie it doesn’t appear to be a contradiction.

Something like a Boston Dynamics robot installed with ChatGPT is quite capable in principle of turning on the Large Hadron Collider, reading its data, and then writing out a natural language description of the result. A p-zombie scientist is exactly like this except that its body is made of skin and bones, not metal, and that its “software” is much more advanced than any current AI.

It has “knowledge” only in the sense that LLM’s have “knowledge”. It isn’t conscious. It is simply capable of processing input and reacting accordingly, whether that be with movement or speech.

Something like a Boston Dynamics robot installed with ChatGPT is quite capable in principle of turning on the Large Hadron Collider, reading its data, and then writing out a natural language description of the result. A p-zombie scientist is exactly like this except that its body is made of skin and bones, not metal, and that its “software” is much more advanced than any current AI.

It has “knowledge” only in the sense that LLM’s have “knowledge”. It isn’t conscious. It is simply capable of processing input and reacting accordingly, whether that be with movement or speech. — Michael

I agree with this. But also

Do you have knowledge?

ChatGPT
Yes, I have a vast amount of information stored from a diverse range of sources up until my last update in January 2022. Feel free to ask me about a wide array of topics, and I'll do my best to provide you with accurate and helpful information.

So, does ChatGPT know things?

So, does ChatGPT know things? — RogueAI

That's an ambiguous question. As it says, it has access to "a vast amount of information". But it doesn't have conscious beliefs like we do, and our kind of knowledge is something akin to "justified true belief".

That's an ambiguous question. As it says, it has access to "a vast amount of information". But it doesn't have conscious beliefs like we do, and our kind of knowledge is something akin to "justified true belief". — Michael

That's true. I feel like we've beaten this topic to death.

If I said, "surely you currently believe the earth is round" and you replied "no, I wasn't thinking of it on that moment", your reply would be more wrongheaded than pedantic.

People seldom if ever truly get these definitions "right", which is why we can't merely refer to them. These seem to only weakly support the association of belief with conscious awareness anyway. The strongest one,

A mental state, representational in character, taking a proposition (either true or false) as its content and involved, together with motivational factors, in the direction and control of voluntary behaviour." — Lionino

Still seems to accommodate unconscious beliefs.

What you refer to as cognitive seems to mean neurological, which can be explained mechanistically. — Lionino

Not neurological, I mean it to refer to the information processing capacity of the brain. A belief is an informational state where a proposition is held to be true. This informational state can be instantiated by a human brain, a p-zombie brain, and the right kind of AI. Whether ChatGPT has beliefs is truly hard to say.

it reminds me of "The game" or "You are now breating manually" of 2000s internet. — Lionino

The Game, the movie? Nice, one of my favs. I'm glad I never saw that meme, I had a horrible spell when I was young where I "forgot" how to breathe automatically and so I couldn't sleep for 11 days!

It has “knowledge” only in the sense that LLM’s have “knowledge”. It isn’t conscious. It is simply capable of processing input and reacting accordingly, whether that be with movement or speech. — Michael

I have been trying to explain that for two pages now, without success.

Still seems to accommodate unconscious beliefs. — hypericin

Unfortunately there is ambiguity in the word conscious(ness). It is not important whether a belief is at the forefront of our minds in a given moment (subconscious or otherwise), or whether we are awaken. Something without mind has no belief.

I mean it to refer to the information processing capacity of the brain — hypericin

What does information mean? Is it abstract concepts summoned by the mind? P-zombies can't do that, and under physicalism nobody can. Is it nervous impulses? Then it is neurological.

I've always struggled a bit with comparison of p-zombie arguments because there are many different interpretations of what a p-zombie is. For example, Chalmers' description is that they are physically identical to ourselves and yet lack phenomenal consciousness. This stems from _why_ he's using the analogy - which is to address the conceivability of phenomenal consciousness residing in something nonphysical.

That's at one extreme, shall we say. At the other extreme, we have a behavioral p-zombie, which walks talks, looks, and behaves exactly like a human but is completely different on the inside. Generally such a description would not be ascribed the label "p-zombie", but if we accept that it is a continuum of characterizations then I think this description is an acceptable addition. Personally I find it no less practical than Chalmer's own. For example, examples like this have helped us hone our intuition about what might pass off as a test of consciousness and what might not - we have concluded that a third-person behavioral test is insufficient.

A more practical variation, would be something more in the middle where we omit Chalmers' requirement that it be physically identical, and put other more lenient constraints on how much it is allowed to differ from the physical structure of humans. Variants of this description are useful in both philosophical discussions and in scientific investigations. For example, it is exactly this analogy that is being increasingly discussed by neuroscientists wanting to devise tests for consciousness. eg:
Bayne et al 2024, "Tests for consciousness in humans and beyond", https://pubmed.ncbi.nlm.nih.gov/38485576/.

Has anyone done a formal review of the different forms of p-zombie?

This stems from _why_ he's using the analogy - which is to address the conceivability of phenomenal consciousness residing in something nonphysical. — Malcolm Lett

I don't think that's the point of Chalmer's thought-experiment.

Previously my view had been that you could catch a p-zombie out with a simple question, like 'what are you afraid of?' or 'what is the most embarrasing thing that ever happened to you?' or even 'how are you?' As the p-zombie has no inner states or feelings whatever, it could never be embarrased or fearful or answer how it is. So, 'gotcha!'

But then I realised that if it was realistic enough - and since I first starting thinking about the issue, ChatGPT has come along - it could fake an answer to those questions.

And that's what made me realise the point of the thought-experiment. Providing that the fake was totally convincing, it could be a very well-constructed mannequin or robot that says 'I fear this' or 'that would be embarrasing', 'I feel great' - and there would be no empirical way of knowing whether the entity was conscious or faking. So I take Chalmer's point to be that this is an inherent limitation of objective or empiricist philosophy - that whether the thing in front of you is real human being or a robot is impossible to discern, because the first-person nature of consciousness is impossible to discern empirically, as per his Hard Problem paper.

[T]here would be no empirical way of knowing whether the entity was conscious or faking. — Wayfarer

Same with us, no? There also is "no empirical way of knowing" (yet / ever) whether any person is "conscious or faking". Which seems more reasonable, or likely, to you, Wayfarer (or anyone): (A) every human is a zombie with a(n involuntary) 'theory of mind'? or (B) every entity is a 'conscious' monad necessarily inaccessible / inexplicable to one another's 'subjectivity'? or (C) mind is a 'mystery' too intractable for science, even in principle, to explain? or (D) mind is a near-intractably complex phenomenon that science (or AGI) has yet to explain? :chin:

@Wayfarer I think that just gets to my point that the p-zombie analogy is used for different discussion purposes, and that the exact definition changes with it.

I'll try to find the reference, but one of Chalmer's works describe a p-zombie as being exactly physically identical. In other words, not only that we cannot empirically find any physical difference using our technology today (fMRI etc) but that we couldn't even with the most advanced physical technology conceivable. At that point, the only way that the p-zombie can be different from a human is that some form of dualism is true. And that is the conceivability argument in that case - that it is conceivable that some form of dualism exists.

And that's what made me realise the point of the thought-experiment. Providing that the fake was totally convincing, it could be a very well-constructed mannequin or robot that says 'I fear this' or 'that would be embarrasing', 'I feel great' - and there would be no empirical way of knowing whether the entity was conscious or faking. So I take Chalmer's point to be that this is an inherent limitation of objective or empiricist philosophy - that whether the thing in front of you is real human being or a robot is impossible to discern, because the first-person nature of consciousness is impossible to discern empirically, as per his Hard Problem paper.

Yes. And I find this particular variant of p-zombie to be very useful.
What's interesting is to try to define clearly what this p-zombie is, in the same form of description as in my prior paragraph. This alone as different variants, some of which are:
* Behavioural-p-zombie: A being that is obscured by a screen so that we cannot observe its nature in any way except through its textual and auditory behaviors. ie: LLMs and the Turing Test.
* Ancient-technology-p-zombie: A being that is empirically identical to humans in all measurable ways using the technology of 1st century scientists, except that it lacks phenomenal consciousness. This is a more precise variant of the behavioral p-zombie, with the addition that scientists of the day can open the skull and observe that there's a brain that looks the same. But they would have no means to identify any potential structural differences.
* Current-technology-p-zombie: Same as above but current technology. This p-zombie must have all the same physical brain structure as humans to the extent that we are unable to identify any differences via fRMI static results and dynamic sequences, or via close examination of neural structures. Many of the debates I see probably use this description.
* Future-technology-p-zombie: Same as above but with future technology that can scan the entire neural structure and sub-structures in in instant.

I think most arguments today apply to one or both of the last two. For example, discussions whether neural activity produce consciousness could be identified with either of the last two, depending on whether you're suggesting that some other physical structure may be present too (eg: Orch-OR).

and there would be no empirical way of knowing whether the entity was conscious or faking

To my point, I don't accept that this statement is true for any given conception of p-zombie. The form of p-zombie changes what we can do empirically. As someone with a reductive materialist viewpoint, I argue that at some point the p-zombie is sufficiently close to human physical structure that it is inconceivable that it doesn't have consciousness.

I would go further and say that modern-technology-p-zombies would be conceivable, but practically impossible. I can conceive of the possibility that dualism is true, and thus that even a future-technology-p-zombie would be empirically indistinguishable from a human. However, if dualism is false, then I hold that anything with the same neural structures as humans (as empirically measured via today's technology) will experience phenomenal consciousness. From a practical point of view, I go even further and state that I believe today's physics is sufficient to explain phenomenal consciousness (ie: our failure is a lack of knowledge rather than a systemic gap in the science). At that point, there is no need for dualism, so why I can still conceive of it as a possibility, I find it extremely unlikely.

(By the way, hi again Wayfarer after a long time, it's nice to see you still here and offering your views)

why, thanks! Nice of you to say so. I'm afraid I'm rusted on to this forum :love: (I'll take in what you have to say and may come back with more later.)

By the way, part of my question regarding definitions of p-zombies comes from a frustration. I have seen implicitly that definitions vary throughout, yet when I wanted to reference something to that effect recently I couldn't find any references.

However, if dualism is false, then I hold that anything with the same neural structures as humans (as empirically measured via today's technology) will experience phenomenal consciousness. — Malcolm Lett

Odd reasoning, it seems to me. There is only one form of being that has 'the same neural structures as humans', that is, humans. If one were able to artificially re-create human beings de novo - that is, from the elements of the periodic table, no DNA or genetic technology allowed! - then yes, you would have created a being that is a subject of experience, but whether it is either possible or ethically permissible are obviously enormous questions.

I can conceive of the possibility that dualism is true — Malcolm Lett

What form of dualism can you concieve of as possibly true? Hylomorphic? Cartesian? Some other variety? What do you think dualism means?

By the way, I put the question to ChatGPT which responded like so. The key phrase I took to be the following:

...the absence of subjective experience in the philosophical zombie suggests that consciousness entails something more than just physical or observable properties. This leads to the conclusion that consciousness has aspects that are not fully captured by physical explanations alone, implying a need for an expanded understanding that possibly includes non-physical dimensions. — ChatGPT

In other words, that it would appear conscious, without actually being conscious. Again,the thought-experiment purports to demonstrate an inherent shortcoming in objective description in respect of ascertaining the reality of subjective states.

Odd reasoning, it seems to me. There is only one form of being that has 'the same neural structures as humans', that is, humans. If one were able to artificially re-create human beings de novo - that is, from the elements of the periodic table, no DNA or genetic technology allowed! - then yes, you would have created a being that is a subject of experience, but whether it is either possible or ethically permissible are obviously enormous questions.

I could well be mistaken or overly simplistic in my understanding, but I believe I was just paraphrasing commonly stated descriptions of p-zombies in the lead-up to that section that you responded to. For example, in The Conscious Mind, Chalmers (1996), pg 96 "someone or something physically identical to me (or to any other conscious being), but lacking conscious experiences altogether". As I understand it, there's no room in that description for any kind of macro or micro physical difference between the p-zombie and the human. And that's regardless of the level of technology used to do a comparison, or even whether such a technology is used. The two are stated as being identical a priori, independent of measurement.

That form of p-zombie is the strictest kind, and its conceivability hinges on the conceivability of some form of metaphysics - ie: something outside of physics that has the conscious experience. This is the dualism to which I am referring.

The conceivability discussion of such a p-zombie annoys me because it used as an argument w.r.t. the possibility of empirically measuring consciousness (ie: for the purpose that you've mentioned), but in reality it's only a test for a person's belief. If I believe that metaphysical processes are not necessary (ie: physics is sufficient for consciousness), then I find the existence of such a p-zombie inconceivable. If I believe that a metaphysical reality is necessary, then I find the p-zombie not just conceivable but possible. Chalmers states quite clearly his bias, eg on (p 96) "I confess that the logical possibility of zombies seems equally obvious to me. A zombie is just something physically identical to me, but which has no conscious experience".

On the other hand, for this discussion so far I have taken an in-between stance and merely said that I find it conceivable that metaphysics is necessary, but I don't believe it to be so. In other words my view is:
1. dualism (existence of both physics + metaphysics) is conceivable
2a. under the a priori assumption that dualism is true, then I find p-zombies logically coherent and thus conceivable
2b. under the a priori assumption that dualism is false, then I find p-zombies logically incoherent and thus inconceivable
3. I hold to the conclusion that dualism is unnecessary to explain consciousness.
4. by Occam's Razor, I prefer the assumption that dualism is false, and I will act accordingly until proven otherwise.
5. However I accept that I cannot prove that dualism is false. Likewise, no-one can prove that it is true. Thus, the existence of p-zombies is conditional. It is possibly conceivable. It is not conceivable in an absolute sense. An individual may be able to conceive of it, but only because of their particular bias; while other individuals cannot.

To belabor my point, if you don't mind, and if I have surmised your own viewpoint correctly, you also reject the conceivability of a p-zombie that is physically identical in all ways to a human - ie: that it's both impossible and inconceivable for something physically identical to a human to be devoid of conscious experience. Not only that, but I find very few people accept such a description of a p-zombie - ie: they find it highly improbable. I take this to imply that they also find this particular variant of p-zombie inconceivable, but perhaps I am making invalid assumptions there.

(FYI, I am taking heavy inspiration from Chalmer's chain of implication: logical coherence --> conceivability --> logical possibility. I'm aware that that represents only one viewpoint, but I'm working within my own limitations).

I could well be mistaken or overly simplistic in my understanding, — Malcolm Lett

No, I think your odd reasoning is correct. If Physicalism is true, then minds are a consequence of certain physical things in particular physical structures following specific physical processes. It naturally follows that, if you take one such physical thing which "contains a mind", if you will, and duplicate it such that now you have a second physical thing in the same physical structure following the same physical processes, it must also "contain a mind".

For example, in The Conscious Mind, Chalmers (1996), pg 96 "someone or something physically identical to me (or to any other conscious being), but lacking conscious experiences altogether". ...The two are stated as being identical a priori, independent of measurement. That form of p-zombie is the strictest kind, and its conceivability hinges on the conceivability of some form of metaphysics - ie: something outside of physics that has the conscious experience. This is th e dualism to which I am referring. — Malcolm Lett

I don't understand what you're getting at here. Let me try and re-phrase it. You're saying that in this example, there's a p-zombie truly indistinguishable from a human.

So, it reacts and speaks as would a human, but it is not really a subject of experience at all.

The p-zombie in this example is a physical thing - quite literally, a physical object, albeit one that is indistinguishable from a human subject. So how does that constitute 'something outside of physics that has the conscious experience'? How is it 'outside of physics'?

(Incidentally, I agree that a p-zombie indistinguishable from a human is hard to imagine, but then, if you had advanced enough robotic technology, it might not be inconceivable. I think the replicants in Blade Runner were biological beings, even if they were the result of bioengineering, so I don't think they'd be considered p-zombies.)

I have the feeling that we have very different ideas of what metaphysics, and what dualism, mean, but let's get to that after clearing the first point up.

Incidentally, I agree that a p-zombie indistinguishable from a human is hard to imagine, but then, if you had advanced enough robotic technology — Wayfarer

A robot is distinguishable from a human. Maybe on the outside they look similar, but you cut one open and there's wires instead of guts. Chalmers means indistinguishable down to the bone, down to the cells in their skin and blood and brains

I get that. I don’t mean mechanical technology but advanced bioengineering. Although I don’t know if it’s relevant.

If by 'bioengineering' you mean making a thing that's identical to a human *down to the last molecule*, then it is relevant, but I wouldn't call that thing a robot - that would be more like a clone or something.

The p-zombie in this example is a physical thing - quite literally, a physical object, albeit one that is indistinguishable from a human subject. So how does that constitute 'something outside of physics that has the conscious experience'? How is it 'outside of physics'?

To be completely frank, I think you're agreeing with me. Chalmers' view is totally bonkers.

But to be more coherent, what I'm trying to do in my own clumsy way is to summarise a particular viewpoint (which I don't hold to), in order to a) comment on why I don't like that viewpoint, and b) to argue for the need for people to be clearer about which kind of p-zombie they are talking about.

I'm being particularly clumsy by mixing those two together, but I can't help it.

I'm using Chalmer's viewpoint because I'm most familiar with it and because it appears to be representative of the general viewpoint held by a sizeable number of philosophers (I don't mean the majority, just that there are plenty who do hold to this). In any case, as I understand it, something is metaphysical if it has some form of existence that is independent of physics. Generally there is assumed to be interaction between the physical and metaphysical, but in some cases it may be only unidirectional - eg: as per epiphonemenalism applied to dualism. This is the Cartesian thesis, that the mind exists in some other plane of existence beyond the physical. According to that theory, a p-zombie according to Chalmer's description is conceivable - it's just a human that lacks a link to its metaphysical mind. Highly impractical and improbable, but conceivable nonetheless.

[UPDATE: I believe "metaphysics" is an area of study, whereas "metaphysical" is a supernatural existence. The two seem almost totally unrelated except for having similar names. I'm referring entirely to the latter. Happy to be corrected on terminology]

But most don't accept Cartesian dualism. And neither does Chalmers. He prefers panpsychism: the theory that everything is physical (no metaphysical stuff needed), but that there's some new fundamental physics that we can't yet measure. In an elaborate way, he uses his p-zombie to conclude that panpsychism is correct. And that outcome I cannot fathom. If everything is physical, then a p-zombie according to his description does not exist.

He prefers panpsychism: the theory that everything is physical (no metaphysical stuff needed), but that there's some new fundamental physics that we can't yet measure. — Malcolm Lett

Don't you mean to say "that everything physical also is psychical"? What I remember from The Conscious Mind is that Chalmers thought that there could be psycho-physical laws ensuring that p-zombies could not exist (i.e. make it physically necessary that they were conscious) but that it was conceivable that such laws didn't exist and that they were not conscious (despite being physically identical to us).

Yes he does use psychical, but I'm paraphrasing to put it into the context of the discussion here.

What is psychical? If it's part of the physical realm, then it's some new fundamental physics that we don't know about. If it's not part of the physical realm, then it's metaphysical and we're back to dualism.

as I understand it, something is metaphysical if it has some form of existence that is independent of physics. — Malcolm Lett

I see. Thanks for clearing that up.

This is the Cartesian thesis, that the mind exists in some other plane of existence beyond the physical. — Malcolm Lett

Descartes' form of dualism, in particular, does posit res cogitans, literally 'thinking thing'. I think it's a problematic concept, but I won't try to spell that out here. But suffice to say that Aristotelian metaphysics (and metaphysics originates from Aristotle's writing, although he did not devise the term, which was devised by a later editor) does not assume the body-mind division that Descartes does. Rather his was the duality of matter and form, a.k.a. hylomorphism, which is very different to Cartesian dualism, although that too would be a major digression.

But to return to Chalmers, I think to get a better idea of what he means, return to this key paragraph in his original Facing up to the Problem of Consciousness, to wit:

The really hard problem of consciousness is the problem of experience. When we think and perceive, there is a whir of information-processing, but there is also a subjective aspect. As Nagel (1974) has put it, there is something it is like to be a conscious organism. This subjective aspect is experience. When we see, for example, we experience visual sensations: the felt quality of redness, the experience of dark and light, the quality of depth in a visual field. Other experiences go along with perception in different modalities: the sound of a clarinet, the smell of mothballs. Then there are bodily sensations, from pains to orgasms; mental images that are conjured up internally; the felt quality of emotion, and the experience of a stream of conscious thought. What unites all of these states is that there is something it is like to be in them. All of them are states of experience. — David Chalmers

So, I don't think that is referring to a 'metaphysical substance' of the kind you appear to be envisaging, although that is an easy inference to draw if you think of it in Cartesian terms. The key point Chalmers is making is about the first person nature of conscious experience - that experience is something that occurs to, is felt by, a subject. And no third-person, objective description can ever embody that.

He prefers panpsychism: the theory that everything is physical (no metaphysical stuff needed), but that there's some new fundamental physics that we can't yet measure. — Malcolm Lett

'Chalmers characterizes his view as "naturalistic dualism": naturalistic because he believes mental states supervene "naturally" on physical systems (such as brains); dualist because he believes mental states are ontologically distinct from and not reducible to physical systems' (~wikipedia). But again, I don't believe this posits any kind of 'thinking substance' in a Cartesian sense. He writes about panpsychism, but I'm also aware he's discussed the 'combination problem' implicit in panpsychism, i.e. how can simple conscious units combine to create the unified subject that we experience as self.

In an elaborate way, he uses his p-zombie to conclude that panpsychism is correct. — Malcolm Lett

No, he does not. I still say you're misunderstanding the intent of his thought-experiment - or perhaps you're seeking to define it in such a way that it doesn't undermine the reductive materialism that you say you're proposing.

My interpretation of the issue is this. The fundamental puzzle of mind, is that it is never truly an object of cognition, in the way that physical objects are. Again, no metaphysical posit is required to prove that. Something nearer a perspectival shift is required: the reason the mind is not objectively graspable, is that it is the subject of experience, that to which or to whom experience occurs, that which cognises, sees and judges. But as Indian philosophy puts it, the eye can see another, but not itself; the hand can grasp another, but not itself. Again, no metaphysical posit required, but it does throw into relief the elusive nature of the subject and its intractibility to the objective sciences.

I think of p-zombies as having come about without the help of anything that is thinking, sentient, conscious. Not anything that might have, even unintentionally, built it with, or later even so much as mentioned, the slightest concept of consciousness. Like another planet that had no contact with anything off-planet. If such a thing is possible - physically identical to us but entirely lacking consciousness - then they are inconceivable. Because such things would not have thoughts of, conversations about, or words for, consciousness.