To illustrate this point, here's an argument with the same structure that would similarly "prove" that gravity doesn't cause things to fall down:

1. In our world, there is gravity and things fall down.

2. There is a logically possible world where there is gravity yet things do not fall down.

3. Therefore, things falling down is a further fact about our world, over and above gravity.

4. So, gravity causing things to fall down is false.

He also doesn't understand what computation is, even though he often makes confident statements about it. He thinks computation is a subjective process, that something only counts as a computation if someone interprets it as such, which is simply wrong, not a debatable topic. And this is the core of one of his other arguments about why consciousness can't be a computational process.

Still, the laws of physics could be anything and it wouldn't matter for this question. The only relevant question is whether our brains are computers, regardless of how the physics work at the lowest level. After all, we have clear proof that you can make computers on the existing laws of physics (I'm typing this reply on one!), so all we need to know is whether our brains are bio-chemical computers. Neuroscience is nowhere near a level where it can answer this, but it at least remains a plausible explanation. After all, we humans can't compute any non-computable function, or at least none that we know of (the Church-Turing thesis).

This sneaks in an implicit axiom: that the brain is not only necessary, but is also sufficient, necessarily, for consciousness (implicitly ruling out some unknown outside, non-materialistic force(s)).

Because a world where things do not fall down is not physically identical to a world in which they don't.

I think the point of arguing about p-zombies is this. Do you believe it's possible for a human being to exhibit all the external characteristics of consciousness without an internal conscious experience? And if you believe that's true, then you can posit a world which is physically indistinguishable from our world through any experiment in which consciousness simply does not exist, because, as far as I know, there is no test that can prove that an individual does have an internal consciousness, and isn't merely mimicking it. Most arguments that p-zombies don't exist sort of rely on the internal conscious experience of the person making it, which no one else has access to -- "I have an internal conscious experience of the world, other people are similar to me and so they must also have those experiences."

That is _not_ true about a world in which gravity does not exist for obvious reasons. That universe would be very different from ours and easily distinguishible through experiment.

I think his point does hinge on whether it's possible for p-zombies to exist, but it's not as silly as you all are making it out to be, and it is not begging the question.

I actually think his weakest point is part 3 and 4, because I think mostly the problem is that we don't really have good definitions of consciousness and related concepts let alone a complete physical explanation of their origins, and his whole argument hinges on the fact that we currently don't have a way to test for internal conscious experience, but I think that might not always be true.

Knowing this, you compare your own experience with reports by others, and find that, despite some startling variety in social and cultural practice, humans all more or less go through life experiencing the world in a way that more or less maps to your own experiences. You find that even Helen Keller, despite her tragic disability, wrote about experiences which you can simulate for yourself. You conclude that if you somehow swapped places with her, she would be able to map the sensory input of your physical sensors to her own experience of the world, and vice versa.

This leads you to think that our physical brains are performing a process that models the world, and it does so consistently. After reading up on people's experiences, you also learn that our subjective experiences are constructed, moment by moment, by a combination of these world models, real-time stimulation, abstract feedback loops of conscious and unconscious thinking.

The more you read, the more evidence you have of this strange loop being the default case for every instance of a human having a brain and being alive.

The Bayesian probability that you are conscious, because of your brain, given all available evidence, approaches 100% certainty. You conclude your brain is more or less the same as anyone else's brain, broadly speaking, and this is supported by the evidence provided by a vast majority of accounts from other similarly brained individuals through all of human history.

Since your brain doesn't have a particular difference upon which to pin your experience of consciousness, and the evidence doesn't speak to any need for explanation, Occam's razor leads you to the conclusion that the simplest explanation is also the best. The living human brain is necessary and sufficient for consciousness, and consciousness is the default case for any living human brain.

The posterior probability that any given human (with a "normal" living brain) is conscious approaches 100% certainty, unless you can specifically provide evidence to the contrary. Saying "but what if p-zombies exist" makes for a diverting thought experiment, but it's rationally equivalent to saying "but what if little invisible unicorns are the ones actually experiencing things" or "what if we're all in the Matrix and it's a simulation" or "what if we're just an oddly persistent Boltzmann brain in an energetic nebula somewhere in the universe."

Without evidence, p-zombies are a plot device, not a legitimate rational launching off point for theorizing about anything serious.

Humans are conscious. We have neural correlates, endless recorded evidence, all sorts of second hand reporting which can compare and contrast our own first hand experiences and arrive at rational conclusions. Insisting on some arbitrary threshold of double blind, first hand, objective replicable evidence is not necessary, and even a bit shortsighted and silly, since the thing we are talking about cannot be directly shared or communicated. At some point, we'll be able to map engrams and share conscious experience directly between brains using BCI, and the translation layer between individuals will be studied, and we'll have chains of double blinded, replicable experiments that give us visibility into the algorithms of conscious experience.

Without direct interfaces to the brain and a robust knowledge of neural operation, we're left with tools of abstract reasoning. There's no good reason for p-zombies - they cannot exist, given the evidence, so we'd be better served by thinking about things that are real.

I would argue this is actually consciousness also. If (and yea, it's a big if) consciousness is an internal model/simulation of how we experience reality, then a simulation of a simulation is still a simulation.

If all civilizations that develop computation and simulation capabilities converge to the development of high fidelity simulations, then it's highly likely that they would create simulations of interesting periods of history, such as the period of time when computers, the internet, AI, and other technologies were developed. We just so happen to be living through that - I still put my odds of living in base reality somewhere above 98%, but there is a distinct possibility that we're all being simulated so that this period of history can be iterated and perturbed and studied, or some such scenario.

Maybe someone ought to start studying the science of universal adversarial simulation attacks, to elicit some glitches in the matrix. That'd be one hell of a paper.

Until 'they' restore the checkpoint and arrange your teams plane to fall out of the sky.

Now imagine an internal video game in a computer system that is being generated from the real world inputs of what it sees/hears/feels around it. You take outside input, simulate it, record some information on it, and output feedback into the real world.

Many people would say this isn't consciousness, but I personally disagree. You have input, processing, introspection, and output. The loops that occur in the human brain are more complex, but you have the same things occurring. There is electrical processing and chemical reactions occurring in the humans mind. Just because we don't understand their exact processing doesn't mean they are unrelated to consciousness. Moreso we can turn this consciousness off with drugs and stop said electrical processing.

As where I can visualize, use internal monologue, vividly recall my memories, etc. at will, by default I do none of the above, and my thoughts are opaque to me. For her, she almost exclusively uses her internal monologue when thinking, and her entire thought process is consciously visible to her. It’s entirely conceivable that other people might not have an experience of “consciousness” resembling anything like what my idea of consciousness is.

(I'm not arguing a particular position, but trying to figure out what to make of this. Also, this is based on what I've read, not personal experience.)

Were they unconscious, or are they now unable to remember what they did? I.e. amnesiac.

Nobody knows whether conscious experience is a requirement or not to "exhibit all of the external characteristics".

It's possible that the only way to get from state N to state N+1 is to include the consciousness function as part of that calculation.

A counter to this would be that a lookup table of states would produce the same external characteristics without consciousness.

A counter to that counter would be that the consciousness function is required to produce state N+1 from state N. The creation of the lookup table must have invoked the consciousness function to arrive at and store state N+1.

The thing we just don't really know is whether state N+1 can be derived from state N without the consciousness function being invoked.

The whole Chinese room argument is based merely on a misinterpretation of computentionalist/physicalist argument.

Of course the computer or person who executes the program does not understand Chinese, they are just performing arithmetic operations, the entity understanding Chinese is the program itself, not the medium on which the program runs.

So a world where people discuss consciousness but where it does not exist? That sounds very implausible.

It's almost like they are purely focused on symbolic logic, even if the stmts and symbols don't truly map to reality unambiguously, or without contradictions.

Advanced AI is definitely not physically identical to humans, and there’s a well understood reason why they might talk about consciousness despite lacking it which doesn’t apply to p-zombies.

One might as well say: it is logically possible to have a universe where the physics are identical to our present world, except the core of the Sun is chocolate... therefore fusion can't be the explanation for why our Sun radiates so much energy.

Getting back to the zombies, presuming there could be a zombie clone of me which is indistinguishable from the real me but it isn't conscious is one that needs far more support than just asserting it. I've heard people try to explain: well, imagine if a powerful computer was simulating you in every respect, that would be a p-zombie. But that is question begging, as it presumes that such a creature wouldn't be conscious.

I feel the same way about Searle's Chinese Room -- the power of the argument is there only if you have already decided that consciousness is mystical.

I can conceive of it about as well as I can conceive of an identical universe lacking the Internet. Both seem like fairly direct logical contradictions, slightly disguised by referring to concepts that we generally think about more abstractly rather than their physical composition.

It's not begging the question. He gives reasons for (2) that support the premise. That the premise essentially leads inexorably to (4) is a feature of the argument structure, not a bug. You have to engage with this reasons for (2) in determining whether or not the argument succeeds.

(1) is supported by noticing that all our explanations of physical dynamics appeals to other physical dynamics. We do not need to mention consciousness or qualitative anything to derive any of the physical dynamics we observe in this world. Thus there is nothing logically incoherent about physical dynamics without consciousness.

(2) follows from the fact that logical possibility just means no contradiction. If we cannot see any contradiction in two propositions being true, then that is defeasible evidence for the logical possibility of both propositions being true.

What does it mean to be "logically possible"?

We could conceive of something that is pure garbage due to our lack of knowledge. Something that could never exist due to nature of the universe, but just because we can conceive of it does not mean it's a valid and non-contradictory state for the universe.

It's possible it's a valid argument from the perspective that it forces us into the corner of stating one of these two conditions must be true: either p-zombies or consciousness requires attributes to our reality that are beyond our current physical understanding.

And sure, plenty of people argue that conceivability is a weak guide to possibility due to our limited knowledge, being imperfect reasoners, etc. That's a fair critique.

>either p-zombies or consciousness requires attributes to our reality that are beyond our current physical understanding.

To be clear, the impossibility of p-zombies implies that there is some as yet unidentified logical/semantic relationship between physical dynamics and consciousness. This would mean that there is no possible world where the physical dynamics is true but there is no consciousness. The possibility of p-zombies supports the idea that there is some further (non-logical) property of the world that supports consciousness. But such a property could have been false in a world very much like our own; one with all the same physical dynamics just without any consciousness. The p-zombie argument is used to raise the credence of there being a further fact about the world that supports consciousness.

It is like if i say there is some property let's call it phi-factor, i am certain i have it, some people have it too, and some do not, but there is absolutely no way for others to tell who has this phi-factor thing and who does not, because it doesn't cause any difference in behavior of people.

This kind of hypothesis doesn't explain anything and does not predict anything, and therefore it is not possible to build any logical chain based on it.

There are good versions of p-zombie argument, e.g. you could say that it is very hard to find difference in behavior of people and p-zombies, but if you create planet like simulation inhabited with p-zombies they will have large differences, e.g. they will never develop art, or science, or religion, or will die out because will not want to have children.

In any case there needs to be some measurable difference in behavior, for argument to be valid. But since this is a normal testable theory, it does not lead to the same kind of self-contradictory statements as p-zombie version, and therefore is not popular with philosophers who want to talk about things they have nothing to say about.

Our conceptual framework for understanding consciousness also matters, and the p-zombie argument is directly relevant to what conceptual framework is a plausible basis for doing a science of consciousness. The zombie argument puts limits on what the brain sciences can say about consciousness as such, i.e. the qualitative feel of subjective experience. The very point of the argument is to elucidate the limits of scientific explanation regarding consciousness. For that it is very consequential.

As far as i can tell the p-zombie argument is a variant 2=3 "proofs" with hidden division by 0. People claim as truth a proposition with no consequence,then claim that a proposition they want to prove follows from it. It does not elucidate anything.

The limited variant of the argument which predicts something does help in understanding the limits, but p-zombie supporters do not like that argument because it also shows the boundaries of what brain sciences can't say, and that is not much.

If you think of science as just a collection of empirical data, then you won't find any value in untestable hypotheses. If you think of science as an enterprise that's aimed towards explanations about the world, then conceptual data matters. Interpretations of quantum mechanics are a fruitful ground for non-testable conceptual work to be relevant to science. Here is one example[1] of the Many Worlds interpretation providing conceptual and intuitive support that helped advance quantum computing.

But beyond that, what an experiment tells us depends on our conceptual framework. When we hear a click in a Geiger counter, are we merely detecting clicks in this particular device, or are we detecting electrons out in the world? This isn't something that an experiment will decide for us. The conceptual framework we are operating with allows us to say the click isn't just the detector going off, and our model of these clicks isn't just predicting when this device will click in the future, but rather that our experiments are detecting the existence of actual electrons too small to interact with without special devices.

[1] https://physics.stackexchange.com/questions/59346/does-quant...

The equivalent of p-zombie hypothesis with quantum mechanics would be if one said that particles in addition to coordinates have to be described by one more variable, which does not affect any of other equations of motion. These type of theories do not have to obey any constraint, and you can trivially produce an infinite amount of them.

You can say that this kind of variable has different value for particles in human brain, therefore study of this additional variable is more important than the study of the rest of physics. But this won't improve your understanding of either the brain or physics, just like p-zombie hypothesis does not.

No, this is not what anyone means by a theory being testable. An interpretation of QM by assumption reproduces all the same results of QM. That's why its an interpretation. In the same way, the p-zombie thought experiment by assumption reproduces all of physics without any deviation. QM interpretations and the p-zombie argument are on the same footing here.

>These type of theories do not have to obey any constraint, and you can trivially produce an infinite amount of them.

This just shows a lack of understanding of what the p-zombie argument is claiming. Perhaps revisit your initial misconceptions rather than piling on the mistakes?

I don't contest your point 1 at all -- I believe in most of there universe there is no consciousness, and for much of Earth's history there was no consciousness here either.

For point 2 -- perhaps "logically possible" is a term of art that I'm not familiar with, so I am perhaps missing the point. But on a plain reading I can't support this point. Recycling a point I made earlier, I can conceive of a world where the center of the sun is made of chocolate, but it is not logically possible.

Point 3 -- the conclusion you have arrived at isn't contested. Materialists are not claiming consciousness is the cause of the physical processes, rather it is the result of them. As I said in my response to point 1, much of earth's history didn't have any conscious experiencers.

We could say: (1) we can conceive of the physical dynamics of this world occurring without waterfalls. (2) if something is conceivable then it is logically possible (3) It is logically possible that the physical dynamics of this world occur without any associated waterfalls.

I don't see what insight this syllogism is presenting: one can imagine a world where the set of actually realized manifestations of physical laws is different, but it doesn't speak to whether the unmanifested things are not present because they are non-physical (at least in part).

How do you know its logically impossible if you can conceive of it? If there's some fact you are aware of that makes it logically impossible, then that means its not conceivable, by the philosophically relevant meaning of the term.

Welcome to eliminative materialism!

No, we don't.

Because, while an individual may experience it, the conjecture that other things do or do not have it is without exception an unverifiable assumption, not an observed phenomenon which calls for an explanation.

> it's actually easier to conceive of a world like ours without subjective experience than one with it.

This is demonstrably false, because no experiencer can observe subjective experience other than their own, and, despite that, describing the world in terms of subjective experience occurring in a vast array of other beings beside the speaker is near-universal, to the point that we pathologize not viewing the universe that way.

Yes, but ultimately, either they do or they don't, and the default assumption is that they don't, unless you favor panpsychism.

You and I have the experience of talking about being conscious because we have the experience of being conscious in the first place. But for a p-zombie to behave exactly the same as us, it would have to have some other mechanism for talking about being conscious that is not dependent on being conscious. So that would mean that our talking about consciousness can be explained by some mechanism other than our being conscious in the first place! Our experience of consciousness, and our talking about experiencing consciousness, could just happen to be one massive coincidence rather than being causally linked! Doesn't seem likely, ergo no p-zombies.

https://www.lesswrong.com/posts/kYAuNJX2ecH2uFqZ9/the-genera...

The entropy gradient is the first one. Of course lots of natural processes have a bit of energy generated so it's not the only part.

Memory is the next one. Being able to take some of that entropy and put it in a more orderly fashion while rejecting the disorganized part. Crystals can use energy to create ordered systems, but they don't have any means of error correcting.

Execution/replay/updating of said memories based on input from the world around it.

Now before humans came along 'life' was the only thing that could readily manage these traits, and that was after a few billion years of trial and error. Humans now have been going down the path of giving other non-living objects these traits. Advanced computer systems are getting closer to the point of recording information and acting on it in a manner that certainly seems like a subjective experience.

Pointing to statistical mechanics and saying the derivative of an exponent is an exponent is an odd way to explain qualia.

Physicalism is conditionally false.

If p-zombies are logically incoherent, the consciousness does not exist. It's an illusion. This is the argument by Daniel Dennet. We are zombies.

I mean it's obvious to any physicalist that we don't really feel anything. There is no I, soul, no suffering in a in a rock, peas soup, or a human. It's all physical process.

"There is no I, soul, no suffering in ... a human. " You have an idiosyncratic definition of suffering. If I offer you the option of having a warm bath or having your skin flayed and then be dipped in lemon juice, which would you prefer?

> which would you prefer?

Prefer is action, learned habituation response. There is nobody inside to see be aware of it according to Dennet. Simple control system with thermometer controlling heater has preference to homeostasis with certain temperature. Consciousness is illusion according to Dennet.

Just because I can verbally express my preferred state does not imply I'm consious.

If there was no conscious experience in this identical p-zombie world, it would be impossible to explain why everybody falsely claims they have conscious experience. If people stop claiming this, then the world is physically different, as people no longer act and produce artifacts such as HN posts discussing the phenomenon.

Or, my summary would be: conscious experience is causal, and so you cannot get the same universe-wide effects without it.

Since a non-p-zombie can sit down and interrogate the details of their conscious experience, then write a book about it, which others read and agree upon the fine details - I find it hard to come up with a p-zombie substitute that wouldn’t just be consciousness by another name.

You mean like talking and writing? As I said, how would p-zombies invent organized religion or other common spiritual beliefs that are false?

> Since a non-p-zombie can sit down and interrogate the details of their conscious experience, then write a book about it, which others read and agree upon the fine details

First, assuming you think that we're not p-zombies, not everybody agrees on the properties of consciousness even though we presumably have such an introspective ability. Therefore what you describe is a kind of fictional just-so story, and clearly doesn't actually happen in all cases.

Second, when there is no fact of the matter as with p-zombies and consciousness, any argument about consciousness only has to be rhetorically persuasive, not factual. Why do so many people agree on the broad properties of ghosts, eg. translucency, pass through physical objects, etc. despite such things not existing? There is no fact of the matter being described, so people just need to like the story being told, or perhaps how it's told.

In such a world, Chalmers and other philosophers of consciousness are just persuasive writers that spin a convincing just-so story connecting fictional internal states to real world observations, and people/p-zombies run with it thinking they learned something meaningful.

Suffice it to say, I think this is uncomfortably close to our world.

If you think that the simulation has conscious experience/qualia.../X, then X gets properties like being non-localized in space and time - you can break the simulation into multiple parts in an essential way and run these parts on data centers across the planet which communicate with each other. Further, you can freeze the simulation for a couple of days and reload. As long as there is no connection to outer signals like the system clock, the simulation wouldn't notice the gap.

If you think the simulation doesn't have consciousness/qualia/X despite accurately replicating humans as measured by instruments, then the simulation is a p-zombie.

"Point 2 is textbook begging the question"

-> It is a thought experiment.

He is proposing a possible postulate to spur talking about the ideas. It isn't a 'proof'.

Just like we don't argue with Schrodinger about the absurdity of a half dead cat.

The question is where does that subjective 0.01% - the rider on top of the elephant come from?

We generally do not pay attention to walking, breathing or brushing teeth and so on.

We can do more complex tasks as well once we achieve unconscious mastery in some subject.

With proper training we can play chess or tennis ("The Inner Game of Tennis") at a high level, without paying attention. In fact it can be detrimental to think about one's performance.

It is the Dennett's "multiple drafts model" - but where does the subjective experience arise when some model is brought to foreground "thread"?

Thus allure of Chalmer's zombies. Why not have a 100% zombie?

There are many stories of people seemingly being conscious, yet not really.

Black out drunks driving home from a bar.

Hypoglycemic shock is another example - my wife's diabetic friend was responding seemingly logically and claiming to be conscious, yet she was not and paramedics were barely able to save her.

A human being can achieve very high levels on unconscious mastery in multiple subjects.

A very tired me gave a remote lecture (on intermediate Python) during Covid where I switched spoken languages mid-lecture and even answered questions in a different language. Meanwhile I was was half asleep and thinking about a different subject matter. I was not really aware of the lecture material - I had given the same lecture many times before - I was on autopilot.

Only after watching the Zoom recording I realized what had happened.

Thus, are there are some actions that our zombie (unconscious) states unable to produce?

Presumably, subjective experience helps in planning future actions. That could be one avenue to explore.

Here is an analogy. When playing a video game, the world is fictional and enemies are algorithmic creations. Yet, while playing that game, it is useful (that is, one plays the game better) by accepting the rules of that world and pretending as if the experiences are real at some level. Eg, "This guy is trying to kill me" vs the reality of "a microprocessor is reading state in memory and as a result is rewriting that state and some of that state shows up on my monitor as colored pixels and I'm not in actual danger."

Although I intellectually believe I'm an incredibly complex mechanism that is simply letting the laws of physics play out, it is useful while playing the game of life to utilize the evolutionary developed fiction that I do have free will.

Here is another intuition pump. Do you believe the weather has a free will, or is it just a physical phenomenon? (presumably the latter) Yet when we talk about the weather, we might say there is a 30% change of rain tomorrow. The reality is it will or it won't rain, but we can't measure the state of the system's initial conditions nor simulate its evolution accurately enough to say exactly what will happen. So we use the convenient fiction that whether it rains or not is statistical. People are too complex that we can't even calculate our own behavior, so it is a convenient fiction to act as if we have free will.

I can certainly imagine a robot that imitates all of human behaviors. If you hit it, it goes "Ow" and retracts, if you ask it if its conscious it says "yes". We can this imagine being created out of our completely physical electrical components, so the question becomes what is the difference between the imitation of consciousness and the consciousness we experience? This is interesting as in this day and age, we can totally imagine building such a robot, yet we'd have a tough time believing it is actually conscious.

Now, whether you are a materialist or not depends entirely on whether or not you believe conscious experience like yours can emerge out of physical components.

My take on this is: Materialism/physicalism is ill defined and materialism/physicalism and dualism are compatible. We consider completely mysterious properties like energy and now even randomness (things happen one way or another for no reason) as being fundamental physical facts about the universe. Theoretically, how does this differ from saying consciousness is a fundamental physical property?

Moreover, you have to consider the fact that the "material" world IS an imagination of the mind. Whatever facts or attributes we assign to being material is limited to the mental facilities of the brain.

At the end of the day, the question is, what fundamental facts do we need to explain the observations that we make? I can observe that I feel, see, hear things. Can the fundamental facts of the current physics model explain this? No? Then we must add to it an additional property, making it part of the standard physics model. If you want proof, you must either A. explain how consciousness can emerge out of existing known "material" processes, B. Admit consciousness as a "material" property and define the process by which it combines, reduces, etc. (the combination problem of panpsychism)