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ESR's New Take on Qualia

3 Post author: billswift 21 August 2009 09:26AM

http://esr.ibiblio.org/?p=1192#more-1192

ADDED:  Even if you disagree with ESR's take, and many will, this is the clearest definition I have seen on what qualia is.  So it should present a useful starting point, even for those who strongly disagree, to argue from.

Comments (51)

Comment author: Psychohistorian 21 August 2009 08:57:35PM *  10 points [-]

Liked this a lot, though it was basically my view already, so I'm decidedly biased.

Interestingly, I don't think he bluntly said the (perhaps) most fundamental part of his position: what the color red looks like is a fact about Mary's brain, not about the color red. This also explains how qualia are essentially incommunicable: I don't have Mary's brain, so I can't really observe what it is like for information to be processed in that brain.

It seems that, in theory, an intelligence capable of reconstructing brains, wiring them into its own consciousness, and running them through stimuli could in fact understand their qualia, though such a procedure may not be meaningfully possible.

Comment author: CronoDAS 21 August 2009 09:57:23PM 2 points [-]

Interestingly, I don't think he bluntly said the (perhaps) most fundamental part of his position: what the color red looks like is a fact about Mary's brain, not about the color red. This also explains how qualia are essentially incommunicable: I don't have Mary's brain, so I can't really observe what it is like for information to be processed in that brain.

I agree with this.

Comment author: billswift 21 August 2009 10:02:34PM 0 points [-]

It was about the effect that actually seeing the color red had on Mary's brain. As opposed to learning about the color red from other sources. His claim was that there was something that could only be learned about the color red by actually seeing it, and that was the effect seeing it has on your mind.

Comment author: Psychohistorian 22 August 2009 04:29:27AM *  1 point [-]

His claim was that there was something that could only be learned about the color red...

That's the issue. I don't think you learn something about the color red; I think you learn something about your mind. There is no objective thing that red looks like; it is the result of certain neurons firing. If Mary's brain were wired differently, the experience of seeing red light would be different if it even existed. The only relevant thing about red light is that it stimulates certain neurons; if you knew absolutely nothing about it except that, you could fully describe explain Mary's experience of seeing red (in theory, of course; neuroscience ain't there yet). On the other hand, you couldn't explain the experience with unlimited information about red light plus only the fact that it stimulated Mary's retina.

Comment author: Peterdjones 21 January 2013 06:19:39PM -1 points [-]

Interestingly, I don't think he bluntly said the (perhaps) most fundamental part of his position: what the color red looks like is a fact about Mary's brain, not about the color red. This also explains how qualia are essentially incommunicable: I don't have Mary's brain, so I can't really observe what it is like for information to be processed in that brain.

That doesn't explain why qualia are incommunciable, since others stuff that happens in brains is communicale. We expect Mary to understand everything except qualia.

Comment author: simplicio 21 January 2013 07:24:16PM 2 points [-]

They are incommunicable because you cannot occupy any arbitrary brainstate you want to. See the ability hypothesis.

Comment author: Peterdjones 21 January 2013 07:26:16PM -2 points [-]

To repeat my point: that doens't explain why other metnal content is communicable.

Comment author: simplicio 21 January 2013 08:59:21PM 2 points [-]

Other mental content is expressible propositionally, whereas to duplicate someone's qualia you have to literally duplicate their brainstate (or at least the functional equivalent of their brainstate).

When I say "Greece is in Europe" I am making a propositional claim that is relatively independent of the precise details of how my brain represents that belief, versus how your brain does. Maybe I am picturing a map, while you are remembering Greece's EU membership. For the purposes of communicating that proposition, nobody cares about what your neural activity looks like when you think about Greece being in Europe. The description is higher level: many brainstates map to a single belief state. This is what makes it communicable.

Comment author: Peterdjones 03 March 2013 02:45:07PM 1 point [-]

Other mental content is expressible propositionally, whereas to duplicate someone's qualia you have to literally duplicate their brainstate (or at least the functional equivalent of their brainstate).

To duplicate something, you of course have to duplicate it. That isn't really the point. What you are tacitly assuming is that qualia cannot be communicated, know or understood without duplication. ie, there is something special about them in that regard. That is how that approach fails as a dissolution. Rather than showing there is nothing special about qualia, it assumes there is something special.

Other mental content is expressible propositionally, whereas to duplicate someone's qualia you have to literally duplicate their brainstate (or at least the functional equivalent of their brainstate).

I don't know about yours, but my qualia don't look like neural activity.

Comment author: TheOtherDave 03 March 2013 04:21:03PM 0 points [-]

I don't know about yours, but my qualia don't look like neural activity.

(blink) Can you clarify how you can know something like this about peterdjones' qualia and not know it about simplicio's? That is, what evidence do you have for the former that isn't equally evidence for the latter?

Comment author: [deleted] 21 January 2013 08:37:05PM 2 points [-]

Other mental content is communicable because it's a lot simpler. All of the data of an entire human brain state, even considering only a snapshot taken at one instant in time, is many orders of magnitude of quantity/complexity beyond what the conscious mind is capable of considering and understanding.

Comment author: Peterdjones 03 March 2013 02:34:58PM 0 points [-]

Other mental content is [...] a lot simpler

Is there independent evidence for that?

Comment author: Johnicholas 21 August 2009 11:31:38AM *  5 points [-]

Is there a rule, in the Mary's room argument, against Mary doing some brain/electricity experiments on herself? Of course, she would be careful to use non-red tools and change her blood somehow so it isn't red either.

I would expect that such a capable scientist could learn what it feels like to see red objects without any red light going through her eyeballs.

Unless I am mistaken, ESR either thinks that these experiments are not allowed, or hasn't thought of that possibility. This makes me believe that ESR's idea that he disagrees with Dennett might be based on reasoning from different ground rules than Dennett.

Comment author: SilasBarta 21 August 2009 02:06:17PM 1 point [-]

Is there a rule, in the Mary's room argument, against Mary doing some brain/electricity experiments on herself? ... I would expect that such a capable scientist could learn what it feels like to see red objects without any red light going through her eyeballs.

The way I see it, it's possible to learn ways to produce the sensation of red, but still learn something upon seeing red.

If each brain is wired up differently from birth, but in ways that achieve similar functionality, then Mary could only learn aggregate and past statistics about the ways brains responded to seeing red. She could make a good guess about the range of responses her own brain is expected to have upon seeing red. But until she sees red, she doesn't know which response within that range is the one she gets.

Comment author: Johnicholas 21 August 2009 03:11:26PM *  3 points [-]

As I understood it, Mary is, in the thought experiment, supposed to be very nearly omniscient - she knows EVERY PHYSICAL FACT about color and human perception of color.

My question is whether she's allowed (before exiting the room) to wire her brain up to a machine that stimulates her neurons exactly as if there was a red thing in front of her.

Would you agree that if she were allowed to use such a machine, then she would know which response her brain in fact would have?

Comment author: SilasBarta 21 August 2009 04:08:14PM *  2 points [-]

Yes, I do, but I think that turns it into an unhelpful question. If she already knows enough to stimulate her neurons to generate what it feels like "exactly as if there was a red thing in front of her", then of course she won't learn anything from seeing red. But knowing enough to do that raises the question of how she could know she's generating the right feeling, which just regresses to the original dilemma. It's like saying, "If Mary knows everything, does she know a subset of everything?"

I thought the point of the scenario was to ask if Mary learns anything from seeing red if, before that, she received sensory data in all modes except color sight -- that is, she could feel or smell or even see black and white images.

The above reformulation is still fair because, for example, she can run simulations of other people that have information about their reactions to red, and information about her own brain, and she can extrapolate to her internal experience. But I would still say that when she sees red, she resolves residual uncertainty, for example, about which of several branching Marys she is.

Comment author: Johnicholas 21 August 2009 05:47:46PM 3 points [-]

As I understand it, the point of the scenario is intended to be an argument against physicalism. Qualia are claimed to be nonphysical, because Mary knew "every physical fact" about color and human color perception, but still (it is claimed) learned something when she saw red for the first time.

Dennett, if I undersand him correctly, argues that the "knowing every physical fact" is a very strong hypothesis, which the exposition of the scenario doesn't pay enough attention to. With so much information and comprehension, Mary is not very much like a human; our intuition that she would say "wow" is not trustworthy.

In particular, I don't think that we actually disagree - your posts seem to come from a physicalist, rather than dualist, conception of the world.

Comment author: UnholySmoke 24 August 2009 01:33:15PM 0 points [-]

Funny how those highly unlikely borderline cases whisk away a lot of the confusion, huh? No committed physicalist can postulate a serious difference between seeing something red and having a virtual red-thing pumped into your optic nerve, I would hope. I think that’s a far more useful scenario than thinking about someone suddenly be able to see colour. In fact, you could probably keep moving a step towards your magical ‘inner perceiver’ and asking whether ‘it’s a real experience of redness’. That’s not to say that qualia are fundamentally dualistic, simply that it’s idle to discuss that question while we clearly don’t have the capacity to get anywhere near it at this point.

I’m always surprised to see people arguing for or against the existence of ‘qualia’ or similar as though they’re making some sort of contribution to the field. Particularly when it’s such nonsense as ‘if brain science doesn’t come up with an explanation for these thingies, it’s not complete!’

Comment author: jimrandomh 22 August 2009 12:47:58AM *  16 points [-]

Mary's Room is invalid because it sneaks in a false assumption: that if something is knowledge, then it can be learned by study alone. As a counterexample to the story of Mary's Room, consider the story of Marty's Bicycle, which I have just made up.

Marty is a brilliant physicist who has suddenly become very interested in bicycles. Unfortunately, his leg is in a cast, so he can't ride one. While he waits for it to heal, he studies their physics, watches people ride bikes, reads guides on bike riding, and interviews top racers - in fact, he studies everything there is to study about bicycles. When the cast is finally taken off, he buys a bicycle, gets on, and immediately falls over.

The ability to recognize red objects is like the skill of riding a bicycle - it can only be acquired by doing it, not by study, because study can only train the linguistic centers of the brain, not the visual processing centers (Mary's room) or the balance centers (Marty's bicycle). This is merely an accident of how our brains work; one could easily imagine a robot that could be told how to recognize red objects or balance a bicycle without having to try it first.

Comment author: komponisto 23 August 2009 06:13:03AM 4 points [-]

This is a standard reply, known as the Lewis-Nemirow "Ability Hypothesis". See here for a critique.

Comment author: CronoDAS 22 August 2009 01:35:12AM 4 points [-]

I once read an anecdote about a person who was determined to prove that "purely theoretical" knowledge was just as good as actual experience, and to prove it, he was going to teach himself how to swim by reading about it. After acquiring what he felt was a sufficient "theoretical" knowledge of swimming, he jumped into a pool and was immediately able to swim, much to the amazement of onlookers.

It's probably false, though.

Comment author: Douglas_Knight 22 August 2009 01:58:17AM *  4 points [-]

I don't believe it. If I were one of the onlookers, I wouldn't be amazed; I just wouldn't believe his claim never to have swum before.

I was quite surprised to learn one day, after riding bicycles for years, that you steer by leaning to the side. This is information that is quite important for riding a bicycle that had never passed through the verbal part of my mind. And when I wanted to test this, I couldn't ask my body about it. Instead I had to pay attention while riding to see what I did; also, I was able to lean or turn the handlebars and see what happens. The communication channel between the verbal part of the mind and the mechanical memory is quite narrow. That's not to say that it's impossible to send information in either direction, but that is a skill that is quite rare, not a matter of deciding to acquire "theoretical knowledge." Also, there's the problem that since people don't normally learn this way, they don't record instructions.

Comment author: Psychohistorian 22 August 2009 04:33:19AM *  3 points [-]

Swimming is a lot easier to figure out prior to doing than bike riding is. Falling, for example, is rather more difficult. It is highly unlikely that someone could do this for any sport or activity that involves significant interactive feedback (e.g. balance or aim).

Comment author: SilasBarta 22 August 2009 05:29:37PM 1 point [-]

It's impossible to jump into a pool without learning something about swimming. At the very least, you start learning about how the water responds to your body. And this will remain true even if you don't consciously try. (There are experiments, for example, where people "learn" to twitch a muscle they can't consciously control because twitching it becomes correlated with turning off an annoying sound.)

Furthermore, it's been my experience that people who think they "can't explain something" really aren't trying. If you really try (and I'm sure people have), you can come up with pointers that greatly demystify swimming, even if they require you to be in a pool to start making sense.

I don't know what I would call the hard limits of a first-timer. If they swam at a competitive level the first time, and I had good reason to believe they'd never practiced, I'd have to admit I underestimated what you can learn without swimming. But it's not unreasonable that someone who was both a quick learner and was told of a known motion that closely approximates good swimming, could swim on the first try.

Comment author: Bo102010 22 August 2009 11:06:36PM 2 points [-]

The first time I went ice skating a couple years ago, I flailed around dangerously for a bit, and was unable to exert much control over my path. I comically ran into a female friend and wound up in an unflattering position, and it was forceful/painful enough for all present to understand that I hadn't done it on purpose...

Then my roommate took me aside and explained what motion to do, with a few hand gestures. After about 45 seconds of explanation, it clicked in my mind, and I went out and was able to skate around quite gracefully in comparison to a few minutes before. I was surprised at how well it worked.

I suspect that this falls into the "quick learner who is told of a motion that approximates good skating," though.

Comment author: SilasBarta 22 August 2009 11:12:52PM 1 point [-]

I suspect that this falls into the "quick learner who is told of a motion that approximates good skating," though.

Yep, sounds exactly right.

Comment author: haig 25 August 2009 11:19:48PM *  0 points [-]

What you describe is what Tim Gallwey calls the 'inner game'. It is, to simplify a bit, training your intuitive subconscious without letting your conscious awareness interfere. Here is a video of him coaching a woman who has never touched a tennis racket to serve using the technique.

Another similar technique is drawing on the right side of the brain.

Comment author: Lightwave 22 August 2009 10:39:48AM 3 points [-]

The ability to recognize red objects is like the skill of riding a bicycle

I don't think the question is about ability. Mary already has the ability to recognize red objects by using a light detector, for example. The question is that, when seeing red for the first time, it seems you've learned something new - i.e. what it feels like to see red.

The question boils down to whether subjective experiences are a form of knowledge.

Comment author: Eliezer_Yudkowsky 22 August 2009 03:54:05AM *  3 points [-]

Good analogy!

Comment author: JamesAndrix 24 August 2009 03:08:00PM *  0 points [-]

This applies to humans, who have fixed systems for different kinds of learning. If marty or mary were AI's they should be able to gain abilities through knowledge directly.

Comment author: byrnema 22 August 2009 12:32:16PM *  4 points [-]

It sounds like many of us agree: the experience of qualia is a real physical phenomenon. One that occurs in our brain somehow and is incommunicable because we don't mutually observe what happens in each other's brains. (Or even our own except in a limited way.)

So what's the other point of view? Why do dualists want to insist that there is a non-physical aspect to qualia?

Comment author: Kaj_Sotala 22 August 2009 01:48:28PM *  2 points [-]

One such point of view is that currently all existing explanations for qualia - even the ones that try to be materialistic - are actually dualist. For instance, suppose we have a materialist-computational explanation of the brain, which explains how each neuron performs a certain type of computation, and how certain activity patterns in the neurons correspond to specific mental states. We find the model to be good and to accurately predict what people will do. So far, so good.

Yet here we run into a problem - we can now fully explain the brain and one's doings in terms of the computational model, without needing to include actual qualia or subjective feelings in the explanation at all. The model works just as well regardless of whether or not we experience phenomenal consciousness, or are p-zombies. In trying to explain mental states, we have actually explained them away and created a theory that has no need for them.

Therefore, the argument goes, assuming we don't deny the existence of qualia entirely, we must dualists. After all, we now have two models, one physical model which doesn't include qualia, and one which assumes their existence but provides no physical explanation.

Comment author: byrnema 22 August 2009 02:36:56PM *  5 points [-]

If this is the dualist argument, then I wouldn't find it compelling but just confused about what reductionism does.

In trying to explain mental states, we have actually explained them away and created a theory that has no need for them.

In the reductionist worldview, higher level things can be explained in terms of lower levels. For example, table salt can be explained in terms of the molecules sodium and chlorine, which in term can be explained in terms of electrons and protons, which in turn can be explained in terms of quarks, etc. Having explained table salt in terms of quarks doesn't mean that its been explained away though; table salt exists just as well as it did before. (There is the argument that categories of things and our frameworks for things don't really exist, but I don't think that is what this debate is about.)

Instead, I'm pretty sure the dualists are asserting that there is some aspect of qualia that cannot be captured physically. So their idea is that the experience of qualia may occur via a physical process (neuron activity) but that it possesses some additional non-physical quality.

I suspect that our paradigm of what the world is like has changed so much that we can't really relate to what the dualist/materialism debate used to be about. I hypothesize that in the past, we thought of "physical things" as the set of things we could touch and manipulate tactilely, but thoughts appeared to be a completely different category. We now all understand that thoughts occur in the brain and are neural activity. (For me, thoughts occur as sounds usually, so when I'm thinking I am activating different memories of sounds that I have, that are in turn associated with and handles for the ideas I'm thinking about. )

I think this view that thoughts = neural activity is pretty mainstream now ... I wonder if dualism is really obsolete then?

Comment author: Psychohistorian 22 August 2009 08:42:17PM *  5 points [-]

we can now fully explain the brain and one's doings in terms of the computational model, without needing to include actual qualia or subjective feelings in the explanation at all.

No. We can now assume that we can fully explain the brain without qualia. If qualia are in fact reductionist, any full understanding of the brain will show how they exist and what causes them. "Assume we have a perfect model of how the brain works that doesn't imply qualia" is no different from asking, "Assume that qualia are essentially dualist." If you can actually generate this model, you have an overwhelming counterargument. But we can't just suppose we have a perfect model of the brain without qualia, because whether such is actually possible is the exact question we are trying to answer.

To foresee a counterargument, this statement quoted (if I'm reading it correctly) also assumes that accurately predicting what people do is the same thing as fully explaining the brain. This creates the possibility that qualia exist, but if they are an effect of behaviour rather than a direct, independent cause, you can pretend they don't by assumption. I think a full explanation of the brain needs to explain everything the brain actually does, rather than merely predicting behaviour. I'm not arguing that qualia have no causal effect; I think the word "cause" gets too muddied to break down at this point, given current science. Only that if they did not have a clear effect that is not explained by another proxy, you could exclude by definition and they could still very much exist.

Comment author: pjeby 22 August 2009 03:39:10PM 0 points [-]

Therefore, the argument goes, assuming we don't deny the existence of qualia entirely, we must dualists. After all, we now have two models, one physical model which doesn't include qualia, and one which assumes their existence but provides no physical explanation.

WTF? AFAICT that just means the whole notion of "qualia" is just begging the question, in precisely the same way that p-zombies and Chinese room arguments do.

Comment author: Peterdjones 21 January 2013 06:17:22PM -1 points [-]

You dont see colours or feel pains?

Comment author: Vladimir_Nesov 21 August 2009 04:28:53PM *  1 point [-]

Downvoted for lack of description of the (topic of the) link.

Comment author: taw 21 August 2009 04:59:40PM -1 points [-]

Seconded, I also downvoted for lack of summary. And ESR is known for talking out of his ass, so I'm not going to bother reading that unless I'm sure this is much more insightful than his typical writing.

Comment author: UnholySmoke 24 August 2009 12:55:26PM 1 point [-]

A “quale” (singular form) is a brain state with the following properties: (a) like the abnormal activation of a colorblind synesthete’s color pathways in the occipital lobe, or like the first-ever feeling of sexual desire, it is in principle an objectively measurable event with detectable correlates in brain and body, and (b) it’s incommunicable.

Ahh, I was fully on board until the 'incommunicable'. Not even sure what it means to say something's uncommunicable by definition, except that it seems to introduce a brand new element of mystery. Is the 'quale', then, the element of the redness that doesn't go across when I tell the other person about the letterbox? Sounds like putting a name on 'the stuff we don't fully understand yet' - not helpful.

To be honest though, it's not a particularly interesting question. We are physics. All we're doing is shedding light on the particular oddities that arise from experiencing the brain from the inside - there are no deep insights here for me.

Comment author: byrnema 24 August 2009 03:12:43PM *  2 points [-]

On the incommunicability of qualia:

First, I disagree that qualia are inherently incommunicable, they just always have been.

As children, we learn what a tree is when someone points to a tree and says, "tree". In this way, "what a tree is" is communicable.

Red is communicable too. However, what you experience when you experience redness has not been communicable, because it happens inside the brain. When someone says they observe something red, you can only assume that they have some experience analogous to your own experience.

But there's no reason why we can't observe the experience indirectly, eventually, as neuroscience develops. Hooked up to the right machine, it could indicate if I'm "experiencing redness", either because I'm observing something red or imagining something red.

Comment author: Alicorn 24 August 2009 04:29:31PM 1 point [-]

As children, we learn what a tree is when someone points to a tree and says, "tree". In this way, "what a tree is" is communicable.

No. This means that the label "tree" is communicable, and that with any luck, native ability to separate natural kinds will fill in what the label is meant to contain. The definition of "tree" is also communicable, but it doesn't involve pointing and isn't closely wedded to the internal mental understanding of treeness. (My mental understanding of treeness is something like "plant that holds its leaves or needles a ways off the ground with a large stick of wood". The definition involves exciting things like "apical dominance".)

Comment author: Peterdjones 21 January 2013 06:16:08PM 0 points [-]

Sounds like putting a name on 'the stuff we don't fully understand yet' - not helpful.

Helpful. We need to put labels on Stuff We Don't Understand yet so that we know what we are talking about when we try t understand it.

Comment author: UnholySmoke 12 April 2013 03:25:57PM 1 point [-]

Peter,

As a general strategy for considering a black box, great. As a vehicle for defining a mysterious 'something' you want to understand, potentially useful but dangerous. Labelling can make a job harder in cases where the 'thing' isn't a thing at all but a result of your confusion. 'Free will' is a good example. It's like naming an animal you plan to eat: makes it harder to kill.

Ben

Comment author: Peterdjones 12 April 2013 03:41:27PM 0 points [-]

But we don't know that qualia aren;t anything and we don't know that about free will either.

Comment author: smoofra 21 August 2009 01:48:26PM 1 point [-]

seems to me that ESR is basically right, except, I'm not sure Dennet would even disagree. Maybe he'll reply in a comment?

Comment author: thomblake 26 August 2009 04:42:09PM 0 points [-]

Yes, by now ESR was corrected in the comments and has mentioned that he probably misread Dennett.

Comment author: billswift 21 August 2009 06:17:49PM 0 points [-]

I'm not sure either, but at the least his explanation of what he thinks qualia is is clearer than any other that I have seen.