P-Zombies Are Fallacious
Friday, December 9, 2011
Follow up to: Making the Question Go Away and Identity Confusion as Definition Confusion, Part II
I’ve talked recently about how the philosophical concept of “identity” is confused because of our confusions with definitions. This is, however, not the only issue within philosophy of mind that seems confused or problematic because of language concerns: this problem also extends to P-zombies, or philosophical zombies. I think that the notion of philosophical zombies and the conclusions/implications drawn from them are based on fallacious argumentation.
Of course, the standard disclaimer applies: if I have only considered an argument for a week that professional academics have debated for years, chances are that I’m missing something huge. And if what I say is correct, chances are that a lot of philosophers should feel really sorry for themselves. However, given that there is no agreed standard as to how long you’re supposed to think about a problem before you’re allowed to post a resolution on a blog, I’m going to proceed to provide my counterargument now. Feel free to refer me to any arguments you feel I haven’t properly addressed.
Also, a not so standard disclaimer applies: A lot of this theory amounts to no more than a summary of Eliezer Yudkowsky’s ideas on the topic, though I’d like to believe that I sprinkled some original thought here and there. I’m nothing special, only the sum of what I have read and understood.
Do Philosophical Zombies Want Philosophical Brains?
Now here is what I bet nearly all of you are thinking: WTF is a Philosophical Zombie?.
I’m here to tell you that, unfortunately, a P-Zobmie is not nearly as fun as you think they are. First and foremost, they are not undead, nor slow, nor lurching, nor brain-hungry. In fact, P-Zombies are a lot like us… more specifically, identical to us in every way, with one — and only one — bold exception: …they lack consciousness.
P-Zombies are the same as humans even down to the atomic level with all appearances of consciousness and deliberation, but with no actual ability to have any thought. As it is said, “the lights are on, but no one is home”.
Now of course, no one actually thinks that P-Zombies exist in real life. But many philosophers claim that P-Zombies are at least logically possible, as in they could exist in principle. And these philosophers also typically claim that this potential existence has a wide range of implications in philosophy.
David Chalmers, one of the biggest proponents of P-Zombies, explains:
If there is a possible world which is just like this one except that it contains zombies, then that seems to imply that the existence of consciousness is a further, nonphysical fact about our world. To put it metaphorically, even after determining the physical facts about our world, God had to “do more work” to ensure that we weren’t zombies.
Basically, as the argument goes, even after we knew every physical fact about the universe — such as the position and speed of every atom (take that, Heisenberg!) — we would still not know if people were conscious or if they were P-Zombies.
And thus if a conscious and non-conscious person are identical in every physical way yet still different, this means there must be a difference that is not physical, which means something that is not physical must exist, and our traditionally naturalist (materialist) metaphysics of there being only matter-energy in space-time are false. (For the purposes of making this essay clear, naturalism will be defined as the position “supernaturalism is incoherent” and materialism will be defined as the position “only matter-energy in space-time exists”.)
Dinosaur Comics by Ryan North (click to enlarge)
The Zombie Mystery
But as many point out, acting the same to us means that P-Zombies would not realize that they were P-Zombies. For we don’t notice that we’re P-Zombies, and if P-Zombies only do what we would do, then P-Zombies also don’t notice they are P-Zombies. The P-Zombie Peter would still type this very essay informed by ideas and memories of what it feels like to be conscious, despite not actually being conscious.
P-Zombies would still talk about consciousness, still claim to be conscious, still argue about P-Zombies. This isn’t a stunning revelation, but actually something that Zombie proponents fully accept. But isn’t this really odd?
We can explain why we, the normal people, talk about consciousness easy enough — we have conscious experiences. But why do these P-Zombies end up motivated to talk about conscious experiences they don’t actually have? Is it just because they mystically somehow act exactly like us?
Thus a flaw in the P-Zombie argument: it assumes that Zombies are capable of preforming certain actions (talking about consciousness, debating philosophy of mind, etc) despite not having the requisite basis for being capable of preforming those actions. Unless something strange, not-yet-explained, and ad-hoc is going on, we should expect only conscious beings to be able to talk about their conscious experiences. Thus leading to absurd scenarios like Eliezer Yudkowsky’s “Zombies: The Movie”.
Think of it like the phenomenon of blindsight — an odd brain disorder where people receive signals to the brain that correspond to sight, but are unable to process it and develop full ideas of what is being seen. This is basically a real-life example of a P-Zombie in at least one area — people going through the motions of sight, but not perceiving sight.
Except here, they don’t just go on business as usual — they are utterly unable to act upon the sight they don’t have. They go through the motions as if they are blind, not as if they are a P-Zombie in this respect. They are able to meta-perceive being able to not perceive sight, and even if they weren’t, they would still not function normally. P-Zombies would be blind too. Likewise, P-Zombies couldn’t have any memories, because that also involves conscious reflection and awareness. Thus P-Zombies couldn’t act upon past events.
Thus we simply cannot actually imagine a P-Zombie acting just like we would, because many of our actions are motivated by the consciousness that P-Zombies simply do not have.
The Zombie Fallacy
So clearly something is going wrong in the zombie argument. But what? Let’s place it in
P1: A P-Zombie is possible.
P2: If a P-Zombie is possible, consciousness is not a physical property.
P3: If materialism is true, consciousness must be a physical property.
C4: Therefore, materialism is false.
And here a P-Zombie is “an entity that is an exact physical duplicate of a human with the sole exception of consciousness” and materialism is “the theory that everything that exists is matter-energy in space-time”.
So far, this argument seems fine. The conclusion is logically valid and both P2 and P3 are obviously true. Even P1 seemd very plausible. So where’s the mistake?
Not too surprisingly, it has to do with P1, namely the concept of “an entity that is an exact physical duplicate of a human with the sole exception of consciousness”. Why? Because such an entity is only possible if and only if materialism is false.
I’ll Do Anything For a Question! Anything!
Quite simply, materialism says that there is nothing more to consciousness than it being a property that results from arranging atoms in a specific manner, just as a cheese sandwich is nothing more than arranging bread and cheese in a specific manner. Thus if materialism is true, any entity that has the physical arrangement of a human will necessarily have consciousness. If materialism is true, a P-Zombie is impossible.
So what is it about a P-Zombie being possible that disproves materialism? Nothing, because materialism must already be false for P-Zombies to be considered possible. Thus notions of P-Zombies beg the question with materialism, assuming materialism to be false to speculate that materialism could be false.
Assuming that P-Zombies are possible is basically assuming that blindsighted people will still be able to somehow act as if they could see, and that people without any memory would still be able to act based on past experiences. This is freaky, and thus requires the assumption of something fundamentally different than how our world currently works — something not physical. Thus saying that P-Zombies are possible is as profound as pointing out that “If there is something that is not physical, than materialism is false” — yeah, that’s true by definition. Good work.
P1 can only true if C4 is true, and C4 can only be true if P1 is true. Thus P-Zombies are fallacious and C4 is invalid.
But Is Materialism Actually True?
Of course, materialism might still be false. I express my thoughts on this in “The Metaphysics Dilemma” — materialism is either likely to be false, or too vague to be useful. But this has no bearing on the possibility of P-Zombies and does not rescue the argument from it’s circularity.
Why? Well, because materialism applies to more than just consciousness — it applies to absolutely everything. But P-Zombies only apply to consciousness. So even if materialism is false, it can still be true for consciousness individually, and thus P-Zombies are still impossible or beg the question.
I think there are quite a few good reasons to think that consciousness is a product of specific arrangements of matter-energy, and don’t require anything magical to make the question go away — I would point to Adam Lee’s essay “Ghost in the Machine” and Greta Christina’s “Why Near Death Experiences Are a Terrible Argument for the Soul” for starters here.
But that isn’t actually relevant to P-Zombies — not even the claim that “materialism doesn’t sufficiently explain consciousness” is directly relevant to P-Zombies — because the point is that even if materialism is false, the possibility of P-Zombies doesn’t make any difference. It’s no better than saying materialism is false because I can imagine it being false.
What Can Be Imagined Isn’t Always So
P-Zombies are impossible because they entail acting upon information that isn’t available, and thus cannot be acted upon — a contradiction. P-Zombies are incoherent because they are based on a theory of consciousness that doesn’t make any sense, and merely makes the question go away, rather than explaining what is going on. And don’t forget they are based on a fallacious circular argument too!
So why is it that we can imagine P-Zombies?
…
Well, I think it is for the same reason we feel like we can imagine souls, gods, and the rest of the supernatural, despite their demonstrated incoherence. The problem is just that people don’t fully think out everything the idea actually entails. There is a significant gap between “I don’t currently see a contradiction” to “there is no contradiction”.
As Eliezer Yudkowsky points out, it’s like saying that all odd numbers must be prime, because 3, 5, and 7 are all prime. You’re just a few seconds away from where the gap shifts, and you see the contradiction despite not seeing it before. Arguments about Gods, souls, P-Zombies, and such are just those people who decided to stop at “7″ for whatever reason.
Thus we can’t actually imagine P-Zombies, just as we can’t actually imagine every odd number being prime. We can only imagine something that we think is similar enough to the P-Zombie hypothesis, except unbeknownst to us we stopped at “7″ and thought no further. We thought we could conceive the “lights are on, but no one is home” analogy, without realizing this would require us to imagine what it is like to not be able to imagine anything, something that is probably not even possible.
So why is it that we can imagine P-Zombies? We actually can’t. P-Zombies join the vast legion of things that don’t make sense, and naturalism remains undaunted. Problem solved.
We may not be able to explain consciousness in a satisfying manner yet, but we still have no reason to think it won’t be a materialist reductionist explanation. Acting as if such a thing would be impossible is like saying that describing an arrangement of cheese and bread does not capture the true essence of what it is to be a cheese sandwich.
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Congratulations! Without even mentioning it, you debunked the Ontological Argument better than the average refutations that I see out there! It’s all the same: P-Zombies and Gods. I did the same here [in portuguese :( ]
A point: of course I can actually imagine a P-Zombie. I have just to imagine a world where naturalism is not true. The impossibility is at imagining P-Zombies and naturalism together.
I feel like these arguments with only one key-premisse always begs the question.
I think that could be a shockingly good point. But I don’t think the ontological argument and the P-Zombies beg the question in quite the same way. I do actually have a refutation of the ontological argument, though: see “Defining Away the Ontological Argument”.
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The Google Translate read isn’t so bad.
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Sort of. But as per my point in “Making the Question Go Away”, I don’t think you can actually conceive of a coherent way that conciousness works without materialist reductionism being true — all of conciousness is based on an arrangement of matter-energy in space-time (see “Reductionism Made Simple” and “The Metaphysics Dilemma” for more clarification on this).
Instead, I think you can merely conceive of yourself conceiving P-Zombies to exist, which is a bit different — you aren’t modeling P-Zombies in your head, you’re modeling a copy of you having the thought “Ah ha, P-Zombies make sense” without actually knowing how that thought comes to be. I can do the same.
Likewise, you have to deal with another problem: how do P-Zombies act conscious without having consciousness, even if that consciousness is somehow nonphysical? To me, it seems like they have to be conscious without being conscious — as any sufficient approximation of consciousness is consciousness.
I am beginning to wonder if “consciousness” is a meaningful word…
I agree that p-zeds discussing the hard problem of consciousness is a ridiculous notion. But couldn’t we amend the definition of p-zeds slightly to exclude only explicit reflections on what it’s like to have inner experiences?
For example, we might suspect philosophers who don’t “get” Chalmers’ point are p-zeds…which is why they can’t relate.
Would you say the same of computers? I intuitively treat a computer like a p-zed and not a being that has inner experience, even as it senses, processes, and outputs in very sophisticated ways.
But hey, maybe I’m wrong and computers DO have inner experience!
Here I would draw a distinction between epistemic and metaphysical possibility. My problem with the argument is that it seems to rely on it being easy to accept that P1 is _epistemically_ possible (which I agree with if we slightly amend the definition as explained above)…but then turning around and treating assent to P1 as assent to _metaphysical_ possibility which does, in fact, beg the question against materialism.
I don’t get what you’re claiming here. Would you mind elaborating on why p-zeds require a difference in atoms?
P.S. — It’s a good thing you included the dinosaur comic, or I would have been way disappointed.
Sure, we could. And it probably would reveal more insight into the nature of consciousness. But unfortunately, it isn’t what current philosophers seem to be doing.
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Your comment and joseph’s comment reminds me of how John von Neumann responded to someone who insisted a “mere machine” could never think: “You insist that there is something a machine cannot do. If you will tell me precisely what it is that a machine cannot do, then I can always make a machine which will do just that!” (source).
Consciousness is too imprecise right now to talk about. That’s kind of the problem of consciousness, though — figuring out what it is, so we can talk about it further.
I personally think consciousness is all about awareness of what your own processes are doing. Thus a computer could be conscious to some degree if it had a program that reports on what its programs are doing — if it was self-reflective.
I’ll write on this more some day. The point of this essay is to get rid of bad ideas of consciousness so we can focus on better ideas.
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I don’t get this. What does epistemically possible mean, and how is it different from metaphysically possible?
Also, your notion of P-Zombie, while conceptually similar, has such radically different implications (namely it wouldn’t rule out materialism) that it shouldn’t be considered the same thing or the same P1.
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I got a bit carried away there. I wanted to make a point about how non-reductionism / supernaturalism is incoherent and implausible. I’ll edit the section later.
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:D
How annoying of them.
The kind of consciousness I have doubts computers could have isn’t a ‘doing’ at all, but an ‘experiencing.’ But then, I don’t think there’s even the slightest reason to believe conscious experience is possible from known physics, except that we have it ourselves. So maybe once we figure that out, it will turn out to be something available to computers too.
And let me tell you: there are some computers I would like to make sentient so I could make them suffer.
Epistemically possible means something is possible “for all I know.” Since — for all I know — it could be the case that materialism is false, scenarios like p-zeds that require materialism to be false are epistemically possible.
Metaphysically possible means that — whether I know it or not — a certain thing could happen due to the nature of reality. So if materialism is true, then p-zeds are impossible due to the nature of reality EVEN IF they’re possible “for all I know.”
There’s also logically possible, which just means there isn’t a logical contradiction. Things can be logically possible even if they are metaphysically impossible. On the other side of the scale, physically possible might be more restrictive than metaphysically possible if there is more to reality than physics.
Then there’s politically possible which is a very narrow range indeed.
Some more research on the types of possibilities and a reference post would be helpful. Feel free, or I’ll have to do it now.
Sort of — It’s a report about what you’re doing. Thus, it’s a specific type of doing, to the point where having an experience is something you do.
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All this would demonstrate is that you don’t have a good understanding of how brains truly work. But you shouldn’t interpret that as disparaging, because I certainly also don’t have such an understanding (conciousness surprises me too). I don’t think anyone does.
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I don’t see any reason to doubt this.
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That sounds malevolent.
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I think this would mean that everything is epistemically possible… what would be an example of an epistemically impossible thing? Sure 1+1 seems like it equals 2, but for all I know, it could be that I just have some odd brain defect, or be dreadfully misinformed about what “2″ means to other people.
See “Knowledge, A Priori and Absolute” and “The End of Cartesian Demons” for more on this issue.
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Makes sense.
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This also makes sense. But where would something like “incoherence” fit in? Is an incoherent proposition possible in any sense of the word? I’m tempted to say no, because we wouldn’t have enough information to answer the question.
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This seems to be one of the things that you should do, and I could respond to, if necessary.