No, the definition of p-zombies literally means that they are physically indentical to a conscious being and, therefore, exhibit the behavior of a conscious being. You could say that they are inconcievable, but that is the entire debate.

To say that they are materially incoherent and that consciousness requires a physical/material change is question begging in referrence to the p-zombie argument. The entire point of the p-zombie argument is to try to show that consciousness is cannot be reduced to physicalism. You would need a lot more support for a physical mind than an implication.

the definition of p-zombies literally means that they are indentical to a conscious being — Chany

If p-zombies are identical to conscious beings, how are they different from us?

Sorry, physically identical to conscious beings, but lacking consciousness.

How can beings physically identical to conscious beings without consciousness behave like having consciousness?

If you are asking for a mechanical explanation of the mind, no one has that answered. If you are asking for a mechanical explanation of a p-zombie, then you are never going to get an answer because even if a p-zombie exists, we could never test it in any meaningful way or even know of its existence. The mechanics of p-zombies do not need to be explained, however; they only need to be concievable. By admitting that p-zombies are logically possible and coherent, you are saying they exist in some possible world, meaning that they can, in same way and in some state of affairs, exist. As such, your argument is question begging when you bring up material incoherence, as, from my understanding, the entire p-zombie argument is supposed to show that consciousness, at its core, is not material.

The best you could do is a Moorean shift, such that:

1. Physicalism is true
2. Consciousness is reducable to the physical
Therefore,
3. P-zombies are inconcievable

Again, however, I do not think you have provided a case for 1.

We can distinguish logical possibility from metaphysical possibility. It is possible that Donald Trump is a staff at Kakao Corporation, but it is not possible that Donald Trump is a fried egg. P-zombies are logically possible, but they are metaphysically not possible.

physically identical to conscious beings, but lacking consciousness. — Chany

'physically identical to water, but not liquid'.

Personally, I would suggest dropping the term "physical" and offering something more meaningful. Can consciousness be reduced to outward bodily behaviour? Can consciousness be reduced to brain activity?

Given the first, I think it obvious that consciousness can't be reduced to outward bodily behaviour. Patients with locked-in syndrome have no (relevant) outward bodily behaviour but are nonetheless conscious. Therefore consciousness is something other than outward bodily behaviour.

But what about brain activity? Can we conceive of something with a normal human brain but without subjective experiences? Given that I could (theoretically) look at my brain and examine its behaviour but not find anything that's like my first-person perspective, I don't find the notion of there being a normal human brain without any associated first-person perspective incoherent. Therefore, according to Chalmers' argument, consciousness cannot be reduced to brain activity.

How can non-conscious p-zombies behave as if they are conscious? — quine

One could always question the notion of behaving as if we're conscious. One might say that we only behave as if the physical laws and prior physical states are such that our behaviour is the determined (or a probable) consequence (which, the physicalist would have say, must be the case).

So unless consciousness is identical to some physical thing, and unless this physical thing is the only physical thing that can causally explain our behaviour, then there's no such thing as behaving as if we're conscious.

The irony is that opponents of the p-zombie argument tend to argue that our behaviour cannot be explained without reference to first-person experiences, but then also that first-person experiences can be reduced to matter and energy, and so must admit that our behaviour can be explained with reference to matter and energy alone – but then when Chalmers et al. try to argue that we can conceive of a thing behaving in a manner identical to us – behaviour that can be explained with reference to matter and energy alone – but without any first-person experiences, they cry foul and argue that reference to first person experiences is required to explain such behaviour.

If the physicalist can't explain human behaviour simply by referring to physical laws and prior physical states of matter then they seem to be admitting that consciousness – the thing required to explain human behaviour – isn't physical.

We can distinguish logical possibility from metaphysical possibility. It is possible that Donald Trump is a staff at Kakao Corporation, but it is not possible that Donald Trump is a fried egg. P-zombies are logically possible, but they are metaphysically not possible. — quine

Yes, you can distinguish between logical possibility and metaphysical possibility. However, the argument only requires logical possibility, as it would mean that what consciousness is cannot be reduced to the physical on a conceptual level. What consciousness would be is ultimately nonphysical.

I do think that there may be something to pointing out that there is a dinstinction between what is logically possible and metaphysically possible, such as saying "there is nothing logically impossible about nonphysical entities or consciousness, but the possible world they reside in is not the actual world. The actual world is physical only and does not possess nonphysical entities." However, I am not sure this being possible is enough to defeat the argument outright. One may still have to argue to show that physicalism is likely, especially in light of this argument, which would show that consciousness, by its very conceptual nature, cannot be explained by purely physical means.

If you define water as a liquid, then the conceptual p-water would not be concievable, it would be impossible. The question revolves around conceivability: is a p-zombie is actually conceivable and, if that is true, what does that imply? Defining consciousness as physical or saying that consciousness is physical from the start without a ton of supporting evidence is not going to solve the issue.

No, the definition of p-zombies literally means that they are physically indentical to a conscious being and, therefore, exhibit the behavior of a conscious being. You could say that they are inconcievable, but that is the entire debate. — Chany

The definition of insanity is doing the same thing over and over and expecting the same result. How can something be "physically" identical to me and still not be conscious like me. That is no different than defining my maternal twin as a p-zombie.

Sure, we have no proof that any of us have minds. I imply that others have minds because they look and behave similarly to me, and I of course, have a mind. So why, or how, would a p-zombie, who doesn't have a mind, feel the need to imply the existence of minds in others? How would it even understand what the term, "mind" is referring to when heard or seen written down. Oh wait, never mind, p-zombies can't hear or see either because they don't have a mind. So then how do they gather information about the world and where do they retain this information in the form of knowledge and understanding?

We have multiple lines of evidence that show that people that aren't fully conscious behave in distinctly different ways than other people that are fully conscious. Take sleep-walkers for instance. Sleep walkers may behave like that know where they are going, but they aren't usually dressed for the trip. People with blind-sight can be aware of something in their vicinity, but can't make out any details. They behave in ways that make them seem unsure about what it is they are experiencing. In other words, people that aren't fully conscious behave strangely - or differently that those of us who are fully conscious. The p-zombie argument simply doesn't hold up as it doesn't take into account simple observations, or simple logical principles.

We have multiple lines of evidence that show that people that aren't fully conscious behave in distinctly different ways than other people that are fully conscious. — Harry Hindu

How do you know that the people you claim to be fully conscious are fully conscious? Because of their behaviour? Then you're begging the question.

So why, or how, would a p-zombie, who doesn't have a mind, feel the need to imply the existence of minds in others? How would it even understand what the term, "mind" is referring to when heard or seen written down. Oh wait, never mind, p-zombies can't hear or see either because they don't have a mind. So then how do they gather information about the world and where do they retain this information in the form of knowledge and understanding?

These questions don't make any sense. It is simply the case that the movement of the p-zombie's body (including the movement of the lungs and vocal chords) is causally explained by the laws of physics and prior physical states of matter. This must be true for the physicalist, as the physicalist doesn't allow for non-physical causes. The issue, then, is whether or not we can conceive of this situation without conceiving of this person having first-person experiences. Chalmers claims that we can; that we don't need to imagine that there's anything that it's like to be this person to imagine the purely mechanical series of causal relations that the physicalist must say actually explains the behaviour (e.g. electrical activity in the central nervous system).

As I alluded to above, your reasoning only works against the possibility of p-zombies if human behaviour cannot be explained by physical causes alone. But then you're accepting the conclusion of the p-zombie argument; consciousness isn't physical.

The definition of insanity is doing the same thing over and over and expecting the same result.

No, it's "mental illness of such a severe nature that a person cannot distinguish fantasy from reality, cannot conduct her/his affairs due to psychosis, or is subject to uncontrollable impulsive behaviour."<sup>1

1</sup>http://dictionary.law.com/Default.aspx?selected=979

These questions don't make any sense. It is simply the case that the movement of the p-zombie's body (including the movement of the lungs and vocal chords) is causally explained by the laws of physics and prior physical states of matter. This must be true for the physicalist, as the physicalist doesn't allow for non-physical causes. The issue, then, is whether or not we can conceive of this situation without conceiving of this person having first-person experiences. Chalmers claims that we can; that we don't need to imagine that there's anything that it's like to be this person to imagine the purely mechanical series of causal relations that the physicalist must say actually explains the behaviour (e.g. electrical activity in the central nervous system). — Michael

Then I guess Chalmers would claim that a computer would continue to play chess after the deletion of the chess-playing program?

If one computer is physically identical in every way to a chess-playing computer, then it would also, necessarily, be playing chess.

P-zombies aren't physically possible.

However, certain traumatic brain injuries can result in a loss of subjectivity.

Then I guess Chalmers would claim that a computer would continue to play chess after the deletion of the chess-playing program?

If one computer is physically identical in every way to a chess-playing computer, then it would also, necessarily, be playing chess.

P-zombies aren't physically possible.

However, certain traumatic brain injuries can result in a loss of subjectivity. — tom

I'm not sure what you're saying here. If you're only saying that consciousness depends on brain activity, then Chalmers would agree. He's a property dualist, after all, not a substance dualist. All he's arguing is that consciousness is not identical to brain activity (or any other physical thing).

And he's not saying that p-zombies are physically possible. He's saying that p-zombies are logically possible.

I'm not sure what you're saying here. If you're only saying that consciousness depends on brain activity, then Chalmers would agree. He's a property dualist, after all, not a substance dualist. All he's arguing is that consciousness is not identical to brain activity (or any other physical thing).

And he's not saying that p-zombies are physically possible. He's saying that p-zombies are logically possible. — Michael

I don't understand how a property dualist could argue that p-zombies are possible, even logically. If they are, then p-minds are also possible. What does that even mean? I think our familiarity with dull people and zombie films lures us into the misconception that it is possible to remove properties from objects arbitrarily.

How do you know that the people you claim to be fully conscious are fully conscious? Because of their behaviour? Then you're begging the question. — Michael

Easy. Ask them if they noticed that they ran out of the house in their underwear. If they didn't then they weren't aware of what they were wearing, but were aware of where they were going. They weren't fully conscious because a normal person that is fully awake would notice this. What I'm getting at is what is present in conscious as it relates to what is out in the world. The more of the world that is represented in the mind, the more conscious a person is.

We could also look at the level of and location of brain activity and compare it to being awake, sleeping, dreaming, sleep-walking, etc.

These questions don't make any sense. It is simply the case that the movement of the p-zombie's body (including the movement of the lungs and vocal chords) is causally explained by the laws of physics and prior physical states of matter. This must be true for the physicalist, as the physicalist doesn't allow for non-physical causes. The issue, then, is whether or not we can conceive of this situation without conceiving of this person having first-person experiences. Chalmers claims that we can; that we don't need to imagine that there's anything that it's like to be this person to imagine the purely mechanical series of causal relations that the physicalist must say actually explains the behaviour (e.g. electrical activity in the central nervous system).

As I alluded to above, your reasoning only works against the possibility of p-zombies if human behaviour cannot be explained by physical causes alone. But then you're accepting the conclusion of the p-zombie argument; consciousness isn't physical. — Michael

But "physical", like "mental", is simply a category derived by the brain and associated with different experiences. Physicality and mentality are simply types of models that our brain creates. We never experience anything physical nor mental. We simply experience information and it could be said that information is the primary substance of the world, not physical or mental things. Thinking in this dichotomy just causes all these philosophical problems (like the mind-body problem). The "substance" that composes our experiences must be similar to the substance of everything else or there is no way for anything to interact. That is not to say that I'm an Idealist, or think that everything is mental, or has mental properties. That would be committing the same fallacy as those that claim everything is physical. The world is neither mental nor physical. It is simply something else and what we call it really doesn't matter, does it?

I'm not sure what you're saying here. If you're only saying that consciousness depends on brain activity, then Chalmers would agree. He's a property dualist, after all, not a substance dualist. All he's arguing is that consciousness is not identical to brain activity (or any other physical thing). — Michael

When I look at your brain, I experience a model of your brain, not your actual brain. My model isn't precise (it's a model after all). My model appears to have a shape, color and orientation relative to the location and orientation of my eyes. I associate these kinds of properties as being "physical". But your brain isn't a physical thing. It is a process - a changing, dynamic system that can only be modeled by my brain in an incomplete fashion and only using the information my senses have access to (Your neurons are too small for my eyes to pick up so my model of your brain is like a mushy glob of biological tissue). So if my model represents certain aspects of your information processing, then how are they not the same, especially if that is all I have access to is my model, not your actual processing of sensory information?

If Chalmers is arguing that consciousness is not identical to brain activity, then why is my perspective located, not just visually, but also with sounds, and tactile sensations, etc. inside my head? All sensations have a property of location, and that location is always relative to the location of my head. For example, touch your thumb and index finger on one hand together, and then close your eyes. Now move your hand about and pay attention to the location of the sensation. You will notice that the sensation's location is always relative to the location of your head, above, below, or to the sides of your head. How can this be? How is it that everything has a location that is relative to my head, where my brain is, - where my brain processes sensory information? Chalmer's has some explaining to do.