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”.)
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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