Mercurial comments on Human consciousness as a tractable scientific problem - Less Wrong

9 Post author: lukeprog 09 September 2011 06:39AM

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Comment author: Mercurial 27 September 2011 01:15:45AM 1 point [-]

Anyway, oddly enough, I understand the details of your argument, but I don't see the big picture that you're presenting.

Ah, then perhaps I'm more confused than I thought! I still haven't identified the source of my confusion, though.

So, would you agree that the question "how does consciousness work" is no different from "how does blood flow work" ? If not (as I suspect is the case), then what's the difference ?

Er... Yes and no. I agree that eventually we should be able to find an answer that sounds as reduced as an answer to "How does blood flow work?" does. But from where we currently stand, they seem to be really, incredibly fundamentally different questions - as long as you understand the question "How does consciousness work?" to be in the hard sense rather than in the easy one.

I think you get near to the crux of the matter in this statement:

Presumably, a sleepwalker's brain, or a robot's circuitry, or a zombie's... er... goo or whatever it is zombies have, would implement this functionality in different ways than normal human brains do; and we could tell whether the sleepwalker/robot/zombie implements this functionality or not by talking to them [...]

Yes, presumably that's the case, and eventually we'll nail that down. But from what we can currently tell, there doesn't seem to be even an in-principle plausible mechanism for adding qualia to a computer's way of processing things. A computer receives input, does some well-defined manipulations, and offers output. Where do qualia come into play? How is it we get the subjective impression of there being a "someone" who is "watching" what's going on in the Cartesian theater? The very concept is internally inconsistent (e.g., how does the homunculus experience?), but the point is the same: there doesn't seem to be any plausible way that we have currently thought of to get from neurons firing to qualia.

I guess the categorical difference is that when asking about blood flow, there's someone who experiences the question and the data and the subsequent answer; but when asking about consciousness, it's the very process of being able to understand the question in the first place that we're asking about. I'm not sure that's entirely equivalent to the hard problem, though.

You might find it helpful to read the Wikipedia page on the hard problem. That might help to explain some of the nuances better than I've been able to thus far. (In particular, it helps to point out that by "hard problem" I don't mean "a challenging problem" but rather "a problem whose potential to be answered even in theory seems in question.")

[...] (as you have pointed out in your thought experiment).

Again, I think that was Yvain.

Comment author: Bugmaster 27 September 2011 11:24:27AM 0 points [-]

I agree that eventually we should be able to find an answer that sounds as reduced as an answer to "How does blood flow work?" does. But from where we currently stand, they seem to be really, incredibly fundamentally different questions...

Ok, that makes sense. I understand now that this is what you believe, but I still don't see why. You say:

But from what we can currently tell, there doesn't seem to be even an in-principle plausible mechanism for adding qualia to a computer's way of processing things. A computer receives input, does some well-defined manipulations, and offers output. Where do qualia come into play?

This, to me, sounds like a circular argument at worst, and a circular analogy (if there is such a thing) at best. You are trying to illustrate your belief that qualia are categorically different from visual perception (just f.ex.), by introducing a computer which possesses visual perception but not qualia, because, due to the qualia being so different from visual perception, there is no way to grant qualia to the computer even in principle. So, "qualia are hard because qualia are hard", which is a tautology. Your next paragraph makes a lot more sense to me:

I guess the categorical difference is that when asking about blood flow, there's someone who experiences the question and the data and the subsequent answer; but when asking about consciousness, it's the very process of being able to understand the question in the first place that we're asking about.

I think that, if you go this route, you arrive at a kind of solipsism. You know for a fact that you personally have a consciousness, but you don't know this about anyone else, myself included. You can only infer that other beings are conscious based on their behavior. Ok, to be fair, the fact that they are biologically human and therefore possess the same kind of a brain that you do can count as supporting evidence; but I don't know if you want to go that route (Searle does, AFAIK). Anyway, let's assume that your main criterion for judging whether anyone else besides yourself is conscious is their behavior (if that's not the case, I can offer some arguments for why it should be), and that you reject the solipsistic proposition that you are the only conscious being around (ditto). In this case, a perfect sleepwalker or a qualia-less computer that perfectly simulates having qualia, etc., is actually less parsimonious than the alternative, and therefore the concept of qualia buys you nothing (assuming that dualism is false, as always). And then, the "hard question" becomes one of those "mysterious questions" to which you could give a "mysterious answer", as per the Sequences.

You might find it helpful to read the Wikipedia page on the hard problem.

I'd actually read that page earlier, and it (along with associated links) seemed to imply that either dualism offers the best answer to the "hard question", or the "hard question" is meaningless as per Dennet -- which is why I took the time to slam dualism in my previous posts.

Again, I think that was Yvain.

Darn, again, I'm sorry. But nevertheless, I think it's a good thought experiment.

Comment author: Mercurial 05 November 2011 06:32:56AM 0 points [-]

This, to me, sounds like a circular argument at worst, and a circular analogy (if there is such a thing) at best.

Mmm. Yes, I think you're right. As I've chewed on this, I've come to wonder if that's part of where I've been getting the impression that there's a hard problem in the first place. As I've tried to reduce the question enough to notice where reduction seems to fail or at least get a bit lost, my confusion confuses me. I don't know if that's progress, but at least it's different!

I guess the categorical difference is that when asking about blood flow, there's someone who experiences the question and the data and the subsequent answer; but when asking about consciousness, it's the very process of being able to understand the question in the first place that we're asking about.

I think that, if you go this route, you arrive at a kind of solipsism.

I'm afraid I'm a bit slow on the uptake here. Why does this require solipsism? I agree that you can go there with a discussion of consciousness, but I'm not sure how it's necessarily tied into the fact that consciousness is how you know there's a question in the first place. Could you explain that a bit more?

Anyway, let's assume that your main criterion for judging whether anyone else besides yourself is conscious is their behavior (if that's not the case, I can offer some arguments for why it should be), and that you reject the solipsistic proposition that you are the only conscious being around (ditto).

Well... Yes, I think I agree in spirit. The term "behavior" is a bit fuzzy in an important way, because a lot of the impression I have that others are conscious comes from a perception that, as far as I can tell, is every bit as basic as my ability to identify a chair by sight. I don't see a crying person and consciously deduce sadness; the sadness seems self-evident to me. Similarly, I sometimes just get a "feel" for what someone's emotional state is without really being able to pinpoint why I get that impression. But as long as we're talking about a generalized sense of "behavior" that includes cues that go unnoticed by the conscious mind, then sure!

In this case, a perfect sleepwalker or a qualia-less computer that perfectly simulates having qualia, etc., is actually less parsimonious than the alternative, and therefore the concept of qualia buys you nothing

It's not a matter of what qualia buy you. The oddity is that they're there at all, in anything. I think you're pointing out that it'd be very odd to have a quale-free but otherwise perfect simulation of a human mind. I agree, that would be odd. But what's even more odd is that even though we can be extremely confident that there's some mechanism that goes from firing neurons to qualia, we have no clue what it could be. Not just that we don't yet know what it is, but as far as I know we don't know what could possibly play the role of such a mechanism.

It's almost as though we're in the position of early 19th century natural philosophers who are trying to make sense of magnetism: "Surely, objects can't act at a distance without a medium, so there must be some kind of stuff going on between the magnets to pull them toward one another." Sure, that's close enough, but if you focus on building more and more powerful microscopes to try to find that medium, you'll be SOL. The problem in this context is that there are some hidden assumptions that are being brought to bear on the question of what magnetism is that keep us from asking the right questions.

Mind you, I don't know if understanding consciousness will actually turn out to yield that much of a shift in our understanding of the human mind. But it does seem to be slippery in much the same way that magnetism from a billiard-balls-colliding perspective was, as I understand it. I suspect in the end consciousness will turn out to be no more mysterious than magnetism, and we'll be quite capable of building conscious machines someday.

In case this adds some clarity: My personal best proto-guess is that consciousness is a fuzzy term that applies to both (a) the coordination of various parts of the mind, including sensory input and our sense of social relationships; and (b) the internal narrative that accompanies (a). If this fuzzily stated guess is in the right ballpark, then the reason consciousness seems like such a hard problem is that we can't ever pin down a part of the brain that is the "seat of consciousness", nor can we ever say exactly when a signal from the optic nerve turns into vision. Similarly, we can't just "remove consciousness", although we can remove parts of it (e.g., cutting out the narrator or messing with the coordination, as in meditation or alcohol).

I wouldn't be at all surprised if this guess were totally bollocks. But hopefully that gives you some idea of what I'm guessing the end result of solving the consciousness riddle might look like.

Comment author: Bugmaster 05 November 2011 08:34:01AM 1 point [-]

I'm afraid I'm a bit slow on the uptake here. Why does this require solipsism?

Well, there's exactly one being in existence that you know for sure is conscious and experiences qualia: yourself. You suspect that other beings (such as myself) are conscious as well, based on available evidence, though you can't be sure. This, by itself, is not a problem. What evidence could you use, though ? Here are some options.

You could say, "I think other humans are conscious because they have the same kind of brains that I do", but then you'd have to exclude other potentially conscious beings, such as aliens, uploaded humans, etc., and I'm not sure if you want to go that route (let me know if you do). In addition, it's still possible that any given human is not a human at all, but one of those perfect emulator-androids, so this doesn't buy you much.

You could put the human under a brain scanner, and demonstrate that his brain states are similar to your own brain states, which you have identified as contributing to consciousness. If you could do that, though, then you would've reduced consciousness down to physical brain states, and the problem would be solved, and we wouldn't be having this conversation (though you'd still have a problem with aliens and uploaded humans and such).

You could also observe the human's behavior, and say, "this person behaves exactly as though he was conscious, therefore I'm going to assume that he is, until proven otherwise". However, since you postulate the existence of androids/zombies/etc. that emulate consciousness perfectly without experiencing, you can't rely on behavior, either.

Basically, try as I might, I can't think of any piece of evidence that would let you distinguish between a being -- other than yourself -- who is consciousness and experiences qualia, and a being who pretends to be conscious with perfect fidelity, but does not in fact experience qualia. I don't think that such evidence could even exist, given the existence of perfect zombies (since they would be imperfect if such evidence existed). Thus, you are forced to conclude that the only being who is conscious is yourself, which is a kind of solipsism (though not the classic, existential kind).

Similarly, I sometimes just get a "feel" for what someone's emotional state is without really being able to pinpoint why I get that impression. But as long as we're talking about a generalized sense of "behavior" that includes cues that go unnoticed by the conscious mind, then sure!

It seems like we agree on this point, then -- yey ! Of course, I would go one step further, and argue that there's nothing special about our subconscious mind. We know how some parts of it work, we have mapped them down to physical areas of the brain, and our maps are getting better every day.

I think you're pointing out that it'd be very odd to have a quale-free but otherwise perfect simulation of a human mind. I agree, that would be odd.

I don't just think it would be odd, I think it would be logically inconsistent, as long as you're willing to assume that people other than yourself are, in fact, conscious. If you're not willing to assume that, then you arrive at a kind of solipsism, which has its own problems.

But what's even more odd is that even though we can be extremely confident that there's some mechanism that goes from firing neurons to qualia, we have no clue what it could be.

Right, which is why I reject the existence of qualia as an independent entity altogether. As per your magnetism analogy:

"Surely, objects can't act at a distance without a medium, so there must be some kind of stuff going on between the magnets to pull them toward one another." Sure, that's close enough, but if you focus on building more and more powerful microscopes to try to find that medium, you'll be SOL.

Right, and the problem here is not that your microscopes aren't powerful enough, but that your very idea of a magnetic attraction medium is flawed. In reality, there are (probably) no such things as "magnets" at all; there are just collections of waveforms of various kinds (again, probably). You choose to call some of them "magnets" and some others "apples", but those words are just grossly simplified abstractions that you have created in order to talk about the world -- because if you had to describe every single quark of it, you'd never get anywhere.

Similarly, "qualia" and "consciousness" are just abstractions that you'd created in order to talk about human brains -- including your own brain. I understand that you can observe your own consciousness "from the inside", which is not true of magnets, but I don't see this as an especially interesting fact. After all, you can observe gravity "from the inside", as well (your body is heavy, and tends to fall down a lot), but that doesn't mean that your own gravity is somehow different from my gravity, or a rock's gravity, because as far as gravity is concerned, you aren't special.

If this fuzzily stated guess is in the right ballpark, then the reason consciousness seems like such a hard problem is that we can't ever pin down a part of the brain that is the "seat of consciousness", nor can we ever say exactly when a signal from the optic nerve turns into vision.

I don't think that we need to necessarily pin down a single part of the brain that is the "seat of consciousness". We can't pin down a single part that constitutes the "seat of vision", either, but human vision is nonetheless fairly well understood by now. The signal from the optic nerve is just part of the larger mechanism which includes the retina, the optic nerve, the visual cortex, and ultimately a large portion of the brain. There's no point at which electrochemical signals turn into vision, because these signals are a part of vision. Similarly, there isn't a single "seat of blood flow" within the human body, but blood flow is likewise fairly well understood.

Similarly, we can't just "remove consciousness", although we can remove parts of it (e.g., cutting out the narrator or messing with the coordination, as in meditation or alcohol).

I'm not sure I follow your reasoning here. What do you mean by "removing consciousness" and "cutting out the narrator", and why is it important ? Drunk (or meditating) people are still conscious, after a fashion.

Comment author: Mercurial 05 November 2011 07:05:14PM 0 points [-]

Basically, try as I might, I can't think of any piece of evidence that would let you distinguish between a being -- other than yourself -- who is consciousness and experiences qualia, and a being who pretends to be conscious with perfect fidelity, but does not in fact experience qualia. I don't think that such evidence could even exist, given the existence of perfect zombies (since they would be imperfect if such evidence existed). Thus, you are forced to conclude that the only being who is conscious is yourself, which is a kind of solipsism (though not the classic, existential kind).

Ah! Okay. Three points:

  • I think you're arguing for something I agree with anyway. I don't think of qualia as being inherently independent of everything else. I think of qualia as self-evident. I don't think my experience of green can be entirely separated from the physical process of perceiving light of a certain wavelength, but I do think it's fair to say that I'm conscious of the green color of the "Help" link below this text box.
  • Even if I did think qualia were divisible from the physical processes involved in perception (which I think would force dualism), I wouldn't be able to conclude that I'm the only one who is conscious. I would have to conclude that as far as I currently know, I have no way of knowing who else is or isn't conscious. So solipsism would then be a possibility, but not a logical necessity.
  • I'm not arguing that p-zombies can exist. I seriously doubt they can. If this is a point you've been trying to argue me into agreeing, please note that we started out agreeing in the first place!

It seems like we agree on this point, then -- yey ! Of course, I would go one step further, and argue that there's nothing special about our subconscious mind.

Er... Except that we're not conscious of it! I'd say that's pretty special - as long as we agree that "special" means "different" rather than "mysterious".

I don't just think it would be odd, I think it would be logically inconsistent, as long as you're willing to assume that people other than yourself are, in fact, conscious.

Sorry, I meant "odd" in the artistically understated sense. We agree on this.

I reject the existence of qualia as an independent entity altogether.

So here, I think, is a source of our miscommunication. I also reject qualia as being independent.

I think part of the problem we're running into here is that by naming qualia as nouns and talking about whether it's possible to add or remove them, we've inadvertently employed our parietal cortices to make sense of conscious experience. It's like how people talk about "government" as though it's a person when, really, they're just reifying complex social behavior (and as a result often hiding a lot of complexity from themselves).

"Quale" is a name that has been, sadly, agreed upon to capture the experience of blueness, or the sense of a melody, or what-have-you. We needed some kind of word to distinguish these components of conscious experience from the physical mechanisms of perception because there is a difference, just like there's a difference between a software program and the physical processes that result in the program running. Yes, as far as the universe is concerned, it's just quarks quarking about. But just like it's helpful to talk about chairs and doors, it's helpful to talk about qualia in order to understand what our experience consists of.

I suspect in the future we'll be able to agree that "qualia" was actually a really bad term to use, with the benefit of hindsight. I suspect consciousness will turn out to be a reification, and thus talking about its components as though they're things just throws us off the track and creates confusion in the guise of a mystery. But even if we dump the term "qualia", we're still stuck with the fact that we experience, and there's a qualitative sense in which experience doesn't seem like it's even in-principle describable in terms of firing neurons. If you told me that it was discovered that there's actually a region of the brain that's responsible for adding qualia to vision (pardoning the horrid implicit metaphor), I wouldn't feel like hardly anything had been explained. So you found circuitry that, when monkeyed with, makes all yellow vanish from my conscious awareness. But how did yellow appear in the first place, as opposed to being just neuronal signals bouncing around? Pointing to a region of the brain and saying "That does it" still leaves me baffled as to how. I don't see how explaining the circuitry of that brain region in perfect synapse-level detail could answer that question.

However, I could totally see consciousness turning out to have this "hard problem" because it's like trying to describe where Mario is in terms of the transistors in a game console.

Similarly, "qualia" and "consciousness" are just abstractions that you'd created in order to talk about human brains -- including your own brain. I understand that you can observe your own consciousness "from the inside", which is not true of magnets, but I don't see this as an especially interesting fact.

On this point, I think we might just be frozen in disagreement. You seem to be taking as practically axiomatic that there's nothing significantly different about consciousness as compared to anything else, like gravity. To me, that view of consciousness is internally incoherent. You can make sense of gravity as an outside observer, but you can't make sense of your own consciousness as an outside observer. That's hugely relevant for any attempt to approach consciousness with the same empirical eye as used on gravity, or magnetism, or any other physical phenomenon. We can look at those phenomena from a position that largely doesn't interact with them in a relevant way, but I cannot fathom a comparable place to stand in order to be conscious of consciousness while not interacting with it.

This is not to say that consciousness is intrinsically more mysterious than gravity. I'm just utterly dumbfounded that you can think that your ability to be aware of anything is somehow no more interesting than any other random phenomenon in the universe.

I don't think that we need to necessarily pin down a single part of the brain that is the "seat of consciousness".

I don't think so either.

We can't pin down a single part that constitutes the "seat of vision", either, but human vision is nonetheless fairly well understood by now.

...

We seem to keep doing this. I agree, because that's part of the point I was making.

Similarly, we can't just "remove consciousness", although we can remove parts of it (e.g., cutting out the narrator or messing with the coordination, as in meditation or alcohol).

I'm not sure I follow your reasoning here. What do you mean by "removing consciousness" and "cutting out the narrator", and why is it important ? Drunk (or meditating) people are still conscious, after a fashion.

Removing consciousness is exactly the process that would turn a person into a p-zombie, yes? So what I've suggested as a general direction to consider for how consciousness appears passes the sanity test of not allowing p-zombies.

As for the narrator... Well, you know how there's a kind of running commentary going on in your mind? It's possible to stop that narration, and if you do so it changes the quality of consciousness by quite a lot.

Meditation, alcohol, and quite a number of other things can all monkey with the way parts of the mind coordinate and also get the narrator to stop narrating (or at least not become an implicit center of attention anymore). And I'm not claiming that doing these things removes consciousness. Quite the opposite, I'm pointing out that drunk and meditating people have a different kind of conscious experience.

Comment author: Bugmaster 06 November 2011 07:08:05AM *  0 points [-]

I would have to conclude that as far as I currently know, I have no way of knowing who else is or isn't conscious. So solipsism would then be a possibility, but not a logical necessity.

True, but you can carry the reasoning one step further. The claim "other people are conscious" is a positive claim. As such, it requires positive evidence (unless it's logically necessary, which in this case it's not). If your concept of qualia/consciousness precludes the possibility of evidence, you'd be justified in rejecting the claim.

Er... Except that we're not conscious of it! I'd say that's pretty special - as long as we agree that "special" means "different" rather than "mysterious".

Fair enough.

We needed some kind of word to distinguish these components of conscious experience from the physical mechanisms of perception because there is a difference...

Well, it depends on what you mean by "perception". If you mean, for example, "light hitting my retina and producing a signal in my optic nerve", then yes, experience is different -- because the aforementioned process is a component of it. The overall process of experience involves your visual cortex, and ultimately your entire brain, and there's a lot more stuff that goes on in there.

...just like there's a difference between a software program and the physical processes that result in the program running.

Hmm, I don't know, is there such a difference ? As far as I understand, when Firefox is running, we can (plus or minus some engineering constraints) reduce its functionality down to the individual electrons inside the integrated circuits of my computer (plus or minus some quantum physics constraints). Where does the difference come in ?

...and there's a qualitative sense in which experience doesn't seem like it's even in-principle describable in terms of firing neurons.

I lack this sense, apparently :-(

If you told me that it was discovered that there's actually a region of the brain that's responsible for adding qualia to vision (pardoning the horrid implicit metaphor), I wouldn't feel like hardly anything had been explained.

As it happens, there's a real neurological phenomenon called "blindsight" which is similar to what you're describing. It's relatively well understood (AFAIK), and, in this specific case, we can indeed point to a specific region of the brain that causes it. So, at least in case of vision, we can actually map the presence or absence of conscious visual experience to a specific area of the brain. I suspect that there are scientists who are even now busily pursuing further explanations.

You seem to be taking as practically axiomatic that there's nothing significantly different about consciousness as compared to anything else, like gravity.

The word "axiomatic" is perhaps too strong of a word. I just don't think that it's possible to treat consciousness as being categorically different from other phenomena, such as gravity, while still maintaining a logically and epistemically (if that's a word) consistent, non-solipsistic worldview.

You can make sense of gravity as an outside observer, but you can't make sense of your own consciousness as an outside observer. [emphasis mine]

Ok, let me temporarily grant you this premise. What about the consciousness of other people ? Can I make sense of those consciousness as an outside observer ? If the answer is "no", then consciousness becomes totally mysterious, because I can only observe other people's consciousness from the outside. If the answer is "yes", then you end up saying, "my own consciousness is categorically different from anyone else's", which seems unlikely to be true, since you're just a regular human like the rest of us.

but I cannot fathom a comparable place to stand in order to be conscious of consciousness while not interacting with it.

I agree, but I don't think this means that you can't "make sense" of your consciousness regardless. In a way, this entire site is a toolkit for making sense of your own consciousness -- specifically, its biases -- and for using this understanding to alter it.

Removing consciousness is exactly the process that would turn a person into a p-zombie, yes? ... Quite the opposite, I'm pointing out that drunk and meditating people have a different kind of conscious experience.

Ah, ok, I get it, and I agree, but I'm still not sure how this relates to the point you're making. If anything, it offers tangential evidence against it -- because the existence of a relatively simple physical mechanism (such as alcohol) that can alter your consciousness points the way to reducing your own consciousness down to a collection of strictly physical interactions.

Comment author: Mercurial 07 November 2011 05:12:42AM 1 point [-]

You know, I think we're getting lost in the little details here, and we keep communicating past one another.

First, let me emphasize that I do think we'll eventually be able to explain consciousness in a reductionist way. I've tried to make that clear, but some of your arguments make me wonder if I've failed to convey that.

Second, remember that this whole discussion arose because you questioned the value of trying to answer the hard problem of consciousness. I now suspect what you originally meant was that you don't think there is a hard problem, so there wasn't anything to answer. And in an ultimate sense, I think you're right: I think people like Thomas Nagel are trying to argue that we need a complete paradigm shift in order to explain how qualia exist, and I think they're wrong. Eventually it almost certainly comes down to brain behavior. Even if it's not clear what that pathway could be, that's a description of human creativity and not of the intrinsic mysteriousness of the phenomenon.

But what you said was this:

Is the answer even relevant ?

As far as I understand, there currently exists no "qualia-detector", and building one may be impossible in principle. Thus, in the absence of any ability to detect qualia, and given the way you'd set up your thought experiment about the sleepwalker, there's absolutely no way to tell a perfect sleepwalker from an awake person. As far as everyone -- including the potential sleepwalker -- is concerned, the two cases are completely functionally equivalent. Thus, it doesn't matter who has qualia and who doesn't, since these qualia do not affect anything that we can detect. They are kind of like souls or Saganesque teapots that way.

This, to me, really sounds like you're saying we can't detect qualia, so we might as well assume there are no qualia, so we shouldn't worry about how qualia arise. Maybe that wasn't your point. But if it was, I stand in firm disagreement because I think that qualia are the only things we can care about!

For some reason I can't seem to convey why I think that. I feel rather like I'm pointing at the sun and saying "Look! Light!" and you're responding with "We don't have a way of detecting the light, so we might as well assume it isn't there." (Please excuse the flaw in the analogy in that we can detect light. Pretend for the moment that we can't.) All I can do is blink stupidly and point again at the sun. If I can't get you to acknowledge that you, too, can see, then no amount of argumentation is going to get the point across.

So all I'm left with is an insistence that if my understanding of the universe is completely off and it turns out to be possible to remove conscious experience from people, I most certainly would not want that done to me - not that I could care afterwards, but I absolutely would care beforehand! So to me, the presence or absence of qualia matters a lot.

But if you cannot relate to that at all, I don't think I'll ever be able to convey why I feel that way. I'm completely at a loss as to how this could possibly be a topic of disagreement.

Comment author: Bugmaster 07 November 2011 07:10:59AM 0 points [-]

You know, I think we're getting lost in the little details here, and we keep communicating past one another.

Sorry, you're right, I tend to do that a lot :-(

I now suspect what you originally meant was that you don't think there is a hard problem, so there wasn't anything to answer.

That's correct, I think; though obviously I'm all for acquiring a better understanding of consciousness.

Eventually it almost certainly comes down to brain behavior. Even if it's not clear what that pathway could be...

I think it's not entirely clear what that pathway is, but there are some very good clues regarding what that pathway could be, since certain aspects of consciousness (such as vision, f.ex.) are reasonably well understood.

This, to me, really sounds like you're saying we can't detect qualia, so we might as well assume there are no qualia, so we shouldn't worry about how qualia arise.

Pretty much, but I think we should make a distinction between a person's own qualia, as experienced by the person, and the qualia of other people, from the point of view of that same person. Let's call the person's own qualia "P" and everyone else's qualia (from the point of view of the person) "Q".

Obviously, each person individually can detect P. Until some sort of telepathy gets developed (assuming that such a thing is possible in principle), no person can detect Q (at least, not directly).

You seem to be saying -- and I could be wrong about this, so I apologize in advance if that's the case -- that, in order to build a general theory of consciousness, we need to figure out a way to study P in an objective way. This is hard (I would say, impossible), since P is by its nature subjective, and thus inaccessible to anyone other than yourself.

I, on the other hand, am arguing that a general theory of consciousness can be built based solely on the same kind of evidence that compels us to believe that other people experience things -- i.e., that Q exists and is reducible to brain states. Let's say that we built some sort of a statistical model of consciousness. We can estimate (with a reasonably high degree of certainty) what any given person will experience in any situation, by using this model and plugging in a whole bunch of parameters (representing the person and the situation). I think you would you agree that such a model can, in principle, exist (though please correct me if I'm wrong). Then, would you agree that this model can also predict what you, yourself, will experience in a given situation ? If not, then why not ? If yes, then how is P any different from Q ?

So all I'm left with is an insistence that if my understanding of the universe is completely off and it turns out to be possible to remove conscious experience from people, I most certainly would not want that done to me...

I agree, but I believe that removing a person's consciousness will necessarily alter his behavior; in most cases, this alteration would be quite drastic. Thus, I definitely wouldn't want this done to me, or to anyone else, for this matter.

However, I think you are contemplating a situation where we remove a person's consciousness, and yet his behavior (which includes talking about his consciousness) remains exactly the same. I argue that, if such a thing is possible, then consciousness is a null concept, since it has literally no effect on anything we could ever detect. As far as I understand, you agree with me with respect to Q, but disagree with respect to P. But then, you must necessarily believe that P is categorically different from Q, somehow... mustn't you ?

If you do believe this, then you must also believe that any model of consciousness that we could possibly build will work correctly for anyone other than yourself. This seems highly unlikely to me, however -- what makes you such an outlier ? You are a human like the rest of us, after all. And if you are not an outlier, and yet you believe that the model won't function for you, then you must believe that such a model cannot be built in principle (i.e., it won't function for anyone else, either), and yet I think you would deny this. As I see it, the only way to reconcile these contradictions is to reject the idea that P is categorically different from Q, and thus there's nothing special about your own qualia, and thus the problem consciousness isn't any harder than the problem of, say, unifying gravity with the other fundamental forces (which is pretty hard, admittedly).

Comment author: Mercurial 07 November 2011 06:43:40PM 0 points [-]

Apparently my reply is "too long", so I'll reply in two parts.

PART 1:

Sorry, you're right, I tend to do that a lot :-(

Hey, apparently I do too!

That's correct, I think

Excellent.

I think it's not entirely clear what that pathway is, but there are some very good clues regarding what that pathway could be, since certain aspects of consciousness (such as vision, f.ex.) are reasonably well understood.

Um... Sure, let's go with that. There's a nuance here that's disregarding the hard problem, but I don't think we'll get much mileage repeating the same kind of detail-focusing we've been doing. :-P

I think we should make a distinction between a person's own qualia, as experienced by the person, and the qualia of other people, from the point of view of that same person. Let's call the person's own qualia "P" and everyone else's qualia (from the point of view of the person) "Q".

Sure, agreed.

I should warn you, though, that I'm not sure that this distinction is coherent. There's some reason to suspect that our perception of others as conscious is part of how we construct our sense of self. So, it might not make sense to talk about "my" conscious experience as distinct from "your" conscious experience as though we start with a self and then grant it consciousness. It might be the other way around.

I emphasize this because explaining Q without ever touching P might not tell us much about P. If we start with conscious experience and then define the line between "my" experience and "others'" experience by the distinction between P and Q, all we do by detailing Q is explain our impression that others are conscious. We might think we're addressing others' P, but we never actually address our P (which, it seems, is the only P we can ever have access to - which might be because we define "me" in part by "that which has access to P" and "not me" by "that which doesn't have access to P").

So with that warning, I'll just run with the intuitive distinction between P and Q that I believe you're suggesting.

Obviously, each person individually can detect P. Until some sort of telepathy gets developed (assuming that such a thing is possible in principle), no person can detect Q (at least, not directly).

I agree, and I would go just a little bit farther: I would argue that it's not possible even in principle to detect Q as a kind of P. If I experience another person's experience from a first-person perspective, it's not their experience anymore. It's mine. Sure, we might share it, like two people watching the same movie. But the P I have access to is still my own, and the Q that I'm supposedly accessing as a kind of P is still removed: I still have to assume that the person sitting next to me is also experiencing the movie.

You seem to be saying -- and I could be wrong about this, so I apologize in advance if that's the case -- that, in order to build a general theory of consciousness, we need to figure out a way to study P in an objective way. This is hard (I would say, impossible), since P is by its nature subjective, and thus inaccessible to anyone other than yourself.

Yeah, I think that's a reasonably fair summary. :-)

I, on the other hand, am arguing that a general theory of consciousness can be built based solely on the same kind of evidence that compels us to believe that other people experience things -- i.e., that Q exists and is reducible to brain states.

I agree with you on this. I just think it's important to recognize that what we will have explained is our impression that others are conscious. That might give us insight into P, and it seems implausible that it wouldn't, but it also doesn't seem clear what kind of mechanism it could possibly reveal for P. At least to me!

I think you would you agree that such a model can, in principle, exist (though please correct me if I'm wrong).

Yes, I agree.

Then, would you agree that this model can also predict what you, yourself, will experience in a given situation ? If not, then why not ? If yes, then how is P any different from Q ?

I'm going to go with "maybe", which I think requires me to answer both the "yes" and "no" branches. :-P

I think it's certainly plausible that this model of Q could predict the behavior of P. But it needn't do so. Why not? Because P and Q are different for precisely the reason that we gave them different names. I'm under the impression that my wife is conscious as a sort of immediate perception; surely I deduce it somehow, probably by my perception of her as a social entity with whom I could in principle interact, but that isn't how it seems to me. I just see her as conscious. So when we explore my perception of her as conscious and we develop a thorough model of her consciousness as perceived by me (and others), what that model does is predict how our perception of her conscious experience changes.

But it requires an extra step to say that if I were her, I would be experiencing those changes as P.

Now, I suspect that this model would work out just fine. I suspect that when we determine that we've modeled Q, that the model of Q will predict my P. (I see this in the Enneagram all the time, in fact: it describes others' experiences, and when I spell out their experiences they often give an "I've been caught!" kind of reaction. When someone does the same to me, I sure feel caught!) After all, part of the impression I get of Q comes from the fact that I know that I would react they way the other is reacting if I were to experience X, which draws me to think that they're experiencing X. So for it to fail to model P, it seems likely that I'd have to react in a way that I would not recognize from the outside (assuming experiencing my own P as Q can be turned into a coherent idea). That seems like it'd be pretty weird.

But we're still left with the fact that the application of the theory to Q feels tremendously different than its application to P. The fact that the model is attempting to explain in part why P and Q are different in the first place makes it difficult for me to see how an explanation of Q alone is going to do it. It feels as though its ability to capture P would be almost coincidental.

(continued...)

Comment author: Mercurial 07 November 2011 06:43:58PM 0 points [-]

PART 2:

I think you are contemplating a situation where we remove a person's consciousness, and yet his behavior (which includes talking about his consciousness) remains exactly the same. I argue that, if such a thing is possible, then consciousness is a null concept, since it has literally no effect on anything we could ever detect.

Yep. I believe that's Eliezer's argument (the "anti-zombie principle" I think it was called), and I agree. That's why I prefaced it with saying that my understanding of the universe would have to be pretty far off in order for my self-zombification to even be possible. So, given the highly improbable event that p-zombies are possible, I sure wouldn't want to become one! Ergo, my own qualia matter a great deal to me regardless of anyone else's ability to detect them.

As far as I understand, you agree with me with respect to Q, but disagree with respect to P. But then, you must necessarily believe that P is categorically different from Q, somehow... mustn't you ?

...

I'm not sure what it would mean for me to agree in terms of Q but not P. I'm not quite sure what you're suggesting I'm saying. So maybe you're right, but I honestly don't know!

If you do believe this, then you must also believe that any model of consciousness that we could possibly build will work correctly for anyone other than yourself. This seems highly unlikely to me, however -- what makes you such an outlier ? You are a human like the rest of us, after all.

Mmm... I'm not saying that I, personally, am special. I'm saying that an experiencing subject is special from the point of view of the experiencing subject, precisely because P is not the same as Q. It so happens that I'm an experiencing subject, so from my point of view my perspective is extremely special.

Remember that science doesn't discover anything at all. Scientists do. Scientists explore natural phenomena and run experiments and experience the results and come to conclusions. So it's not that exploring Q would just happen and then a model emerges from the mist. Instead, people explore Q and people develop a model that people can see predicts their impressions of Q. That's what empiricism means!

I emphasize this because every description is always from some point of view. For most phenomena, we've found a way to take a point of view that doesn't make the difference between P and Q all that relevant. A passive-voice description of gravity seems to hold from both P and Q, for instance. But when we're trying to explore what makes P and Q different, we can't start by modulating their difference. We have to decide what the point of view we're taking is, and since part of what we're studying is the phenomenon of there being points of view in the first place, that decision is going to matter a lot.

And if you are not an outlier, and yet you believe that the model won't function for you, then you must believe that such a model cannot be built in principle (i.e., it won't function for anyone else, either), and yet I think you would deny this.

I think that if a model of Q fails to inform us about P, then it will fail for P regardless of whose perspective we take.

However, I suspect that a good model of Q will tell us pretty much everything about P. I just can't fathom at this point how it might do so.

As I see it, the only way to reconcile these contradictions is to reject the idea that P is categorically different from Q, and thus there's nothing special about your own qualia, and thus the problem consciousness isn't any harder than the problem of, say, unifying gravity with the other fundamental forces (which is pretty hard, admittedly).

Well, part of the problem is that we know P is categorically different than Q. Or rather, I know my P is categorically different than Q, and if Q is going to have any fidelity, everyone else will be under the same impression from their own points of view.

I can guarantee that any model that claims I don't have conscious experience is flat-out wrong. This is perhaps the only thing I'd be willing to say has a probability of 1 of being true. I might discover that I'm not experiencing what I thought I was, but the fact that I'm under the impression of seeing these words, for instance, is something for which I believe it is not possible even in principle to provide me evidence against. (Yes, I know how strong a claim that is. I suppose that since I'm open to having this perspective challenged, I should still assign a probability of less than 1 to it. But if anything deserves a probability of 1 of being true, I'd say the fact that there is P-type experience is it!)

However, I can't make a claim like that about Q. I'm certainly under the impression that my wife is conscious, but maybe she's not. Maybe she doesn't have P-type experience. I don't know how I could discover that, but if it were possible to discover it and it turned out that she were not conscious, I wouldn't view that as a contradiction in terms. It would just accent the difference between P-type experience and my impression of Q-type experience. Getting evidence for my wife not being conscious doesn't seem to violate what it means for something to be evidence the way "evidence" against my own consciousness would be.

I'm oversimplifying somewhat since consciousness almost certainly isn't a "yes" or "no" thing. Buddhists often claim that P-type consciousness can be made "more conscious" through mindfulness, and that once you've developed somewhat in that direction you'll be able to look back and consider your past self to not have been "truly" conscious. However, the point I'm trying to make here is that we actually start with the immediate fact that P is different than Q, and it's upon this foundation that empiricism is built. We can't then turn around and deny the difference from an empirical point of view!

However, in spirit I think I agree with you. I think we'll end up understanding P through Q. I don't see how since I don't see how to connect the two empirically even in principle. But science has surprised philosophers for three hundred years, so why stop now? :-D

Comment author: [deleted] 05 November 2011 10:41:32AM *  0 points [-]

Basically, try as I might, I can't think of any piece of evidence that would let you distinguish between a being -- other than yourself -- who is consciousness and experiences qualia, and a being who pretends to be conscious with perfect fidelity, but does not in fact experience qualia.

As I discussed here - see also this comment for clarification - we should in theory be able to discover if other beings have qualia if we were to learn about their brains in such microscopic detail that we are performing approximately the same computations in our brains that their brains are running; we then "get their qualia" first-hand.

As for arguing about qualia verbally, I hold qualia to be both entirely indefinable (implying that the concept is irreducible, if it exists) and something that the vast majority of humans apprehend directly and believe very strongly to exist. There is little to be gained by arguing about whether qualia exist, because of this problem - the best that can be achieved through argument is that both of you accept the consensus regarding the existence of this indefinable thing that nonetheless needs to be given a name.

Comment author: Bugmaster 05 November 2011 01:10:14PM 0 points [-]

Ok, I read your article as well as your comment, and found them very confusing. More on this in a minute.

As for arguing about qualia verbally, I hold qualia to be both entirely indefinable...

How is that different from saying, "I found qualia to be a meaningless concept" ? I may as well say, "I think that human consciousness can best be explained by asdfgh, where asdfgh is an undefinable concept". That's not much of an explanation. In addition, this makes it impossible to discuss qualia at all (with anyone other than yourself, that is), which once again hints at a kind of solipsism.

...and something that the vast majority of humans apprehend directly and believe very strongly to exist.

This is weak evidence at best. The vast majority of humans apprehend all kinds of stuff directly (or so they believe), including gods, demons, honest politicians, etc. At least some of these things have a very low probability of existing, so how are qualia any different ? In addition, regardless of what the vast majority of people believe, I personally disagree with this "consensus regarding the existence of this indefinable thing", so you'll need to convince me some other way other than stating the consensus.

Note that I agree with the statement, "humans appear to act as though they believe that they experience things, just as I do" -- a statement which we may reduce to something like, "humans experience things" (with the usual understanding that there's some non-zero probability of this being false). I just don't see why we need a special name for these experiences, and why we have to treat them any differently from anything else that humans do (or that rocks do, for that matter).

Which brings me back to your article (and comment). In it, you describe qualia as being indefinable. You then proceed to discuss them at great length, which means that you must have some sort of a definition in mind, or else your article would be meaningless (or perhaps it would be meaningless to everyone other than yourself, which isn't much better). Your central argument appears to rest on the assumption that qualia are irreducible, but I still don't understand why you'd assume that in the first place.

In short, qualia appear to be a "mysterious answer to a mysterious question": they are impossible to define, irreducible, and totally inexplicable -- and thus impossible to study or even discuss. They are a kind of elan vital, and therefore not terribly useful as a concept.