A proof that p-zombies are logically incoherent.

[Zep]

What if a p-zombie is not consious of being concious?

 

[Mercutio]

Why do materialists still use this definition?, why haven´t they started calling things what they are?.

Mary

Welcome to the forum, Mary!

My answer...the same reason we still say "sunrise". Because our language works well enough to understand one another most of the time.

 

[drkitten]

Agreed, with the quibble that your "are" really means "may be, but we can never know for certain, even in principle." Actually...now that I think about it, the "internal percepts and qualia" presupposes some mentalisms I am not completely comfortable with. The "red" we see is not an inner qualia, it is an external stop sign, or water bottle, or fire extinguisher. Phrasing the question as if there are necessarily inner qualia to explain presupposes a particular answer.

Well, I certainly know that I have inner qualia, because I percieve them. Of course, from your perspective, I might be deluded/lying/a p-zombie, without qualia. But I personally am willing to nail my colors (ahem) to the mast that for some subset of people inner qualia exist -- that subset, of course, being myself and a possibly unknowable set of people like me. (And since you stated you were color-anomolous, I am fairly confident that your qualia, if they exist at all, are different than mine. Not a proof, but a darned good conclusion.)

I am afraid I don't understand. If we define ostensively, is this quale that I am describing presupposed to exist? Again, I see the red stop sign; I do not "perceive the image" of the red stop sign. It is this "image" (or quale) step that leads to confusion.

Again, I'm perfectly confident in acting on my personal introspection of the red stop sign to believe that there is a perceptual abstraction of "redness" that is instantiated by the stop sign, but not tied to it.

What you see, I don't know.

Hmmm...the same problem rears its ugly head: how do we learn the phrase "awareness of consciousness". How can we possibly know that we are aware of being conscious? Is there a knowledge of awareness of consciousness? A cognizance of knowledge of awareness of consciousness? And turtles all the way down?

No more than it's "redness" all the way down. I have my own qualia, of which I am aware -- and part of those qualia include awareness of qualia themselves. I can easily imagine the existence of a creature without qualia (which to me would be a pretty good description of what I consider a p-zombie to be), and I can also easily imagine the existence of a creature with qualia, but without qualia-of-qualia. Basically, awareness without self-awareness. (I don't think that I can conceive of a creature that is self-aware, but not aware that it is self-aware, since I think if you can go around that loop once, you can go around an unbounded number of times. But that's a separate argument, one that Hofstatder makes extensively in _Godel, Escher, Bach_.)

Now, of course, the problem is that I might be mistaken. What I perceive as "redness" might not in fact be "redness" at all, as you and the rest of humanity define it. I learned the word, and I guessed at a referent for the word.... but I might have guessed wrongly and will almost certainly never know it barring some philosophical, technological, and possibly theological breakthrough.

Similarly, I have what I consider to be a quale regarding consciousness. But as you point out, I might be wrong in that, too.

But any way you slice it, the idea that p-zombies cannot exist because the act of declaring yourself conscious proves that you are is ludicrous. Unfortunately, that appears to be Ian's argument.

 

[dougsmith]

Hi folks, new on the board, though I did write a "hello" in the newbie thread.

...

I guess I'm not sure why I should be impressed by the proof ... it's just a re-stating of the reductive materialist position. If consciousness reduces to brain states, then of course it's an impossibility (a logical impossibility) to preserve brain states while eliminating consciousness.



I'd have thought that was uncontroversial ...

Am I missing something?

 

[Q-Source]

Welcome to the forum, Mary!

My answer...the same reason we still say "sunrise". Because our language works well enough to understand one another most of the time.

You can say that regarding other words and concepts that are not so controversial. But "conscioussness" makes the difference. It is precisely why these sort of discussions arise.

Sunrise is a well defined word that noone can refute. There is no confusion there. I have a question for you, as a materialist, are you unsure or believe that you are not conscious (in the same way Ian understands this concept)?

Mary

 

[Dark Jaguar]

I think we can in fact confirm that our experience of "color" or "depth" or even "hearing" in general is the same. Simply put, we merely need enter a Borg collective.

 

[Mercutio]

You can say that regarding other words and concepts that are not so controversial. But "conscioussness" makes the difference. It is precisely why these sort of discussions arise.

You read my mind! I actually wrote, then erased, a similar thought (I wanted your welcome to be more prominent). Consciousness is, like sunrise, close enough for common speech. The problem, as you imply, comes when physics tries to describe how the sun literally rises over our immobile earth, or when neurology tries to find the underlying processes that "generate consciousness". Phrasing it that way implies a special status to consciousness--if not dualism, close enough. It leaves something undiscovered and undiscoverable in our consciousness research, because it assumes an a priori existence of something to find.

Sunrise is a well defined word that noone can refute. There is no confusion there. I have a question for you, as a materialist, are you unsure or believe that you are not conscious (in the same way Ian understands this concept)?

Mary

Um...I am not a materialist. I am a pragmatist, and as such, in the way Ian understands the concept, since there is no way to determine whether or not one (even oneself) is conscious, the question is irrelevant. It is not worth spending time on, as nothing can give evidence one way or the other (by the very definition of p-zombie).

 

[Interesting Ian]

But, see, as you know from previous conversations with me, I don't know that I am conscious, separate from the sensory data I am taking in and the automatic (or at least, I have no reason a priori to suppose that it is anything but automatic) associations I form from those data. I don't know the difference between seeing a tree and being conscious of seeing a tree, so I do not, by my understanding of your argument, know that I am conscious.

I don't know the difference between seeing a tree and being conscious of seeing a tree either.

Let me try to get to the heart of the confusion. When I say I see a tree I mean I have certain characteristic experiences -- namely a visual experience of brownness (trunk of tree and branches) and visual experience of greenness (leaves) related to each other in a particular characteristic pattern. So in this sense seeing a tree and being conscious of seeing a tree mean precisely the same thing. So in this sense seeing a tree necessitates by definition that I am also conscious of what appears to be a tree.

On the other hand, if you mean by "perceiving" or "seeing" a tree the particular physical occurrences such as various wavelengths of light being reflected off the tree and entering our eyes, and causing certain characteristic physical activity in the brain, then I would declare that this is not the whole story. In addition to all this physical activity there is the actual raw experience of seeing a tree.

Now I do assert that I know with absolutely certitude that I have these certain characteristic visual experiences. I cannot, however, have such certainty that other people have such experiences. I have their verbal reports, their reactions and so on, but for all I know they might be wholly lacking in any such raw experiences.

I cannot and do not seriously believe they are lacking such conscious experiences though. For one thing it's absolutely psychologically impossible to believe such a thing.

I suspect though that our respective views of the world are so completely alien that we are simply talking past each other.

Perhaps I am a p-zombie;

Possibly, but then why shouldn't everyone be a p-zombie apart from me? In which case, should this be true and I were able to psychologically embrace this fact, then it's an awful lonely world I find myself in!

 

[PixyMisa]

Well, humans can drive their responses by observation of their actual own, internal conscious state. Can we think of any questions that would trick a P-zombie that it could not answer without having consciousness?

No, by definition. The p-zombie acts in all ways like a conscious being. Therefore it can answer any question a conscious being could answer. Therefore it has access to a source of information that acts exactly like consciousness. Therefore it is conscious.

 

[Mercutio]

Well, I certainly know that I have inner qualia, because I percieve them. Of course, from your perspective, I might be deluded/lying/a p-zombie, without qualia. But I personally am willing to nail my colors (ahem) to the mast that for some subset of people inner qualia exist -- that subset, of course, being myself and a possibly unknowable set of people like me. (And since you stated you were color-anomolous, I am fairly confident that your qualia, if they exist at all, are different than mine. Not a proof, but a darned good conclusion.)

Really? You perceive inner qualia? I perceive stop signs, water bottles, and fire extinguishers. The characteristics of these things (the shape, color, emotional reaction, associations with rewards, memories of past experiences, movement within my visual field, etc.) are multiply processed in parallel, with no one place where there is "a quale" to point to. The only place these things are whole are in the outside world, as the stimulus that I perceive.

Again, I'm perfectly confident in acting on my personal introspection of the red stop sign to believe that there is a perceptual abstraction of "redness" that is instantiated by the stop sign, but not tied to it.

What you see, I don't know.

It is a difficult concept, for those who are fluent in our ordinary language, which in this case is insufficient to explain the real process. The concept of "red" does not exist in your perception of it, but in your reinforcement history in the language community. "Redness" is defined most clearly by "what things our speakers call red". As we learn our colors, we discriminate more and more clearly because of our reinforcement history. The "abstraction" is nothing more than the generalization along one characteristic of a stimulus (wavelength, though not precisely; as you no doubt know, the mechanisms of color vision mean that mixtures of wavelengths can be perceived as a monochromatic light of a different wavelength). The abstraction is simply the interaction of your visual system and the wavelengths in the external world, along with your reinforcement history. "Redness" as an internal cognitive entity is superfluous to the explanation.

No more than it's "redness" all the way down. I have my own qualia, of which I am aware -- and part of those qualia include awareness of qualia themselves. I can easily imagine the existence of a creature without qualia (which to me would be a pretty good description of what I consider a p-zombie to be), and I can also easily imagine the existence of a creature with qualia, but without qualia-of-qualia. Basically, awareness without self-awareness. (I don't think that I can conceive of a creature that is self-aware, but not aware that it is self-aware, since I think if you can go around that loop once, you can go around an unbounded number of times. But that's a separate argument, one that Hofstatder makes extensively in _Godel, Escher, Bach_.)

Now, of course, the problem is that I might be mistaken. What I perceive as "redness" might not in fact be "redness" at all, as you and the rest of humanity define it. I learned the word, and I guessed at a referent for the word.... but I might have guessed wrongly and will almost certainly never know it barring some philosophical, technological, and possibly theological breakthrough.

(not really a response to this, but just because I am enjoying this exchange--I don't have access to my notes right now, but if memory serves, one really nice exploration of this issue is phrased around "the pain problem" in behaviorism. Pain, for some who get into this argument, is the ultimate in qualia that cannot be denied. The behavioral analysis of this is, I think, something you would enjoy reading.)

Similarly, I have what I consider to be a quale regarding consciousness. But as you point out, I might be wrong in that, too.

But any way you slice it, the idea that p-zombies cannot exist because the act of declaring yourself conscious proves that you are is ludicrous. Unfortunately, that appears to be Ian's argument.

Ok, there we agree. Although I have, in the past, very much enjoyed fencing with Ian on this one.

 

[PixyMisa]

Peoples' arguments thus far are begging the question by simply assuming reductive materialism is true.

Nope. My "proof" doesn't require materialism of any sort.

 

[PixyMisa]

Basically to suppose a p-zombie knows it is conscious is to rule out the logical possibility of p-zombies.

Yup.

The justification for ruling out the logical possibility of p-zombies has been entirely unforthcoming.

Ask the p-zombie. It will tell you that it is conscious. Bang! The whole concept collapses.

Presupposing reductive materialism is of course viciously circular.

Neither reductionism nor materialism is required.

I'm still awaiting PixyMisa's response.

This was already explained in the initial post.

 

[PixyMisa]

I guess I'm not sure why I should be impressed by the proof

You shouldn't be. It's perfectly straightforward and not particularly clever. Merely true.

it's just a re-stating of the reductive materialist position. If consciousness reduces to brain states, then of course it's an impossibility (a logical impossibility) to preserve brain states while eliminating consciousness.

No.

There is no mention at all of reductionism, materialism, or brain states. The same conclusion arises under any form of idealism or dualism.

To act in all ways like a conscious being, the p-zombie must have an internal system that acts in all ways like consciousness. The end.

I'd have thought that was uncontroversial ...

Am I missing something?

You're not missing anything; you are imputing something that is not present. The argument does not rely on reductive materialism, merely on definitions.

 

[PixyMisa]

Their definition could be restated as, "P-zombies satisfy every single definition we have to describe and verifiy consciousness, yet we define them as unconscious."

Yes.

 

[PixyMisa]

A further reply:

We know that we are conscious simply because we are conscious.

So does the p-zombie. Ask it.

But since a p-zombie is not conscious it could not possibly know it is conscious in the very same way as we know we are conscious.

Except that is does. Ask it.

In other words it can't be its consciousness which makes it "know" it is conscious.

But if you ask it, it will tell you that this is exactly the case.

Basically to suppose a p-zombie knows it is conscious is to rule out the logical possibility of p-zombies.

If you ask the p-zombie if it is conscious, it will affirm that it is. If you question it on the nature of consciousness, or on its conscious experiences, it will answer exactly a conscious being would. The only way this is possible is if it possesses something - call it sploip - that acts exactly like consciousness. P-zombies are sploipful.

But it is impossible to distinguish between sploip and consciousness, even in principle. That's by the definition of p-zombies. Sploipful beings and conscious ones act the same, in every way. So the distinction between sploip and consciousness is a false one, and p-zombies are conscious.

It doesn't matter what origin you propose for consciousness, or what properties you ascribe to it. The p-zombie has those characteristics. Epistemology is irrelevant; the concept of p-zombies is incoherent by definition.

 

[dougsmith]

There is no mention at all of reductionism, materialism, or brain states. The same conclusion arises under any form of idealism or dualism.
The argument does not rely on reductive materialism, merely on definitions.

Oh, sorry, I did misunderstand ... It does assume a form of reductionism. Let's see.

A p-zombie is exactly like a human in all ways except that it isn't consciously aware, right?

Fair enough.

it is under the illusion that it is conscious. But that illusion acts exactly the same as consciousness itself. To an external observer, the p-zombie exhibits all the signs of consciousness. The p-zombie itself knows perfectly well that it is conscious, just as you and I do.

Words like "under the illusion" and "knows perfectly well" assume that the p-zombie is having internal states. This is precisely what needs proving.

P-zombies exhibit all the external and internal properties of consciousness, so there are conscious. The distinction between p-zombies and consciousness is a distinction without meaning.

They exhibit all the external properties of consciousness. If you are a reductionist (as I tend to be) then you will say that they ipso facto exhibit all internal properties as well. But this is not demonstrated in the proof.

 

[PixyMisa]

Words like "under the illusion" and "knows perfectly well" assume that the p-zombie is having internal states. This is precisely what needs proving.

It's not an assumption. The p-zombie must have internal states in order to answer the questions.

They exhibit all the external properties of consciousness. If you are a reductionist (as I tend to be) then you will say that they ipso facto exhibit all internal properties as well. But this is not demonstrated in the proof.

Nope.

Those external properties are generated by some internal process. The internal process produces results that are identical all ways to consciousness. Don't believe me? Ask the p-zombie; it will tell you.

Ask it about the nature of its internal processes, and it will tell you that they are of exactly the same nature as yours.

 

[uruk]

I'm not sure if I got PixyMisa argument right but I think it goes like this:

the concept of a p-zombie is like an object that looks, smells, and tastes just like an apple. It grows on trees just like an apple and is exactly just like an apple in every concievable way except that it is not an apple. The statement makes no sense or rather it is contradictory. How can that object be just like an apple in every concievable way but yet not be an apple? It assumes that there is something that is not percieveable or detectable in any way that differentiates the object from being an apple dispite having the exact same qualities of being an apple. As if the things which defines and makes up what an apple is is different from actually being an apple. Just like Ian is assuming that "conciousness" is somehow different from that which defines or what makes conciousness conciousness.

Do I have this right, or have I buggered it?

 

[dougsmith]

It's not an assumption. The p-zombie must have internal states in order to answer the questions.

Why? That isn't in the proof. It must have internal physical states in order to produce the appropriate behavior. If you say it must have internal mental states, you're just assuming what needs to be proved.

Those external properties are generated by some internal process. The internal process produces results that are identical all ways to consciousness. Don't believe me? Ask the p-zombie; it will tell you.

Er ... the p-zombie will make sounds. As for it "telling" me anything, again, that's what needs to be proved. So far all this "proof" shows is that the external behaviors are generated by internal physical processes. Great. So what?

 

[Dark Jaguar]

So? That's the entire point! Those physical processes are processING data. What did you think "processing" meant? It just means data is going through some process, and on a comuter, that is completely physical.