Perception of Color: Separating the Physical from the Supernatural

[Jacob Perry]

For some people there seems to be something which is color that exists outside of electromagnetic radiation. As the typical question goes "Is your red my green?" I don't understand the argument though. If we look at what we mean by color the only thing we can possibly say is: "Well when my optic nerve reacts to light of this frequency I my conscientiousness perceives a thing I call green". I don't understand how you can postulate that there is something that is green-ness without going through this definition.

If we call a certain frequency green and furthermore agree within reason what cultural and even emotional significance is attached to that thing then we don't have any conflict. The supposition that "your red is my green" implies some sort of supernaturalism that color is something besides the sum of the electromagnetic radiation that triggers a response to a set of neurons.

Furthermore, the question is non-scientific as there is nothing that is testable and even if it was truth there are absolutely no consequences.

I can see that this is an interesting subject to consider briefly, but when it was brought up in a philosophy class I am taking I was a bit confused, the rest of the class seemed to just take for granted that somehow color can be separated from the physical phenomenon.

To me this seems a question that is barely worth posing. Richard Dawkins puts it well in "The God Delusion" where he says that just because we can form something as a question in our language doesn't mean that it makes any sense or deserves any sort of answer.

I actually somewhat disagree with Richard Dawkins. I have thought about this before and realized that it is possible that everyone's perception of a color is different even though they call it the same thing. Non-Scientific=true as it is impossible to prove and pointless to ponder on but, I think it can lead us to other questions which could help psychologists out. Questions such as why people percieve the same thing in a completely different way.

 

[nitknight]

Hi All
I just started a blog and posted my first post (http://ponderingsofanidlephilosopher.blogspot.com/2010/01/your-red-my-green.html)
with the title "Your Red My Green". I sent the link to my friends and was just trying to see whether it turns out on Google search. To my surprise I find this thread with the same title! Well I've not read all posts on this thread but will surely do. Till that time if anybody wants to read my view about this please make a visit to my blog, and enlighten me by posting comments.

 

[madness]

http://en.wikipedia.org/wiki/Same_color_illusion

The above illusion should make it clear that our perception of colour is governed by more than just physical wavelengths. Going back to the original question, I think most people can distinguish between their perception of something and the thing itself, ie our perception of colour is not the same as the physical thing that caused it. One is mental ("qualia"), the other physical. If only the physical wavelength mattered, we would all be "P-zombies" (http://en.wikipedia.org/wiki/P_zombie).

 

[Pythagorean]

http://en.wikipedia.org/wiki/Same_color_illusion

The above illusion should make it clear that our perception of colour is governed by more than just physical wavelengths. Going back to the original question, I think most people can distinguish between their perception of something and the thing itself, ie our perception of colour is not the same as the physical thing that caused it. One is mental ("qualia"), the other physical. If only the physical wavelength mattered, we would all be "P-zombies" (http://en.wikipedia.org/wiki/P_zombie).

That example can be logically explained though. It makes sense that because the square in question is behind the shade of the cylinder, we adjust for it. This is because our brains are more geared for building a world model (of what's going on all at once) and simplifying it, then it is for building isolated models. Not that we can't build specific models, it's just more natural for us to look at the whole picture. Remember that evolution has cleaved the survivalist out of all life, leaving the scraps to be recycled. If you go back and look at that picture, you can see that the squares are the same color if you ignore the rest of the picture (even though your eyes are still taking in the whole picture).

Also, on P-zombies. I would naturally agree with the criticisms (on the same page) as a physicalist. I generally tend to agree with Daniel Dennet on his philosophical approach to consciousness. Of course, I personally would like to take a scientific approach to consciousness and test the philosopher's assertions.

 

[madness]

Yes it can be explained but it wasn't my intention to find an illusion that can't be explained. I was trying to draw attention to the fact that our perception of colour and the physical wavelengths emmited from an object are two different things. It is perfectly conceivable that one person's red is another person's green, or that one person's red is a colour that another person can't even imagine.

 

[Pythagorean]

It is perfectly conceivable that one person's red is another person's green, or that one person's red is a colour that another person can't even imagine.

I haven't seen this in my life yet. Everyone that I've ever worked with in the lab agrees that our HeNe lasers are red, for instance. A colorblind person wouldn't see it as green. They might mistake it for green, since red and green look the same to them, but that's also physically explainable.

 

[madness]

Yes but the point is that when they each say it is "red", they only have their own understanding of red to compare it to, ie the same red that they have experienced since they were little. The fact that everyone agrees the laser is red only goes to show that people consistently perceive that wavelength in the same way (as individuals).
And what's the difference between experiencing something as green and mistaking it for green?

 

[Pythagorean]

Yes but the point is that when they each say it is "red", they only have their own understanding of red to compare it to, ie the same red that they have experienced since they were little. The fact that everyone agrees the laser is red only goes to show that people consistently perceive that wavelength in the same way (as individuals).
And what's the difference between experiencing something as green and mistaking it for green?

Well yes, this still a neuroscience problem as Evo said. When we learn about new things in the world, we're tied to the setting and associations with that new thing (not just colors, this goes for just about anything we've learned). It comes to no surprise then, that people have different "thought circuits" associated with the color red, as they encountered them at different times in different settings in their lives.

This is why if you study for a test in the room where you learned the test material, you have a better chance at recalling the information.

It's actually very difficult to escape our initial learning of a "thing". We're tied to it. For instance, if you try to read a list of names of colors, and the letters that make up the names (orange, red, green) are made with different colors, we'll suffer cognitive dissonance because we know that red is red. You can do this test yourself: about 4:30 on the video below:

http://www.ted.com/talks/james_geary_metaphorically_speaking.html

I don't mean to discount philosophy here. My point is that philosophy has already done it's job in this realm. Science has caught up and answered most of the questions posed by philosophy here, or are in the process of answering them. Neuroscience has made leaps and bounds in the last 20 years.

 

[madness]

I maybe wasn't clear in the last post. What I mean is that if one person grew up seeing red things as green and vice versa (obviously this has to be with respect to some other person), then you would never know. He would still say "yes that laser is definitely red", but would be experiencing what you think of as green.

 

[Pythagorean]

I maybe wasn't clear in the last post. What I mean is that if one person grew up seeing red things as green and vice versa (obviously this has to be with respect to some other person), then you would never know. He would still say "yes that laser is definitely red", but would be experiencing what you think of as green.

That would be difficult to refute since we have no way of measuring experience yet, but is their any logical reason to believe that or was it pulled out of the air? For instance, why would it be another color of mine they experienced? Why not a completely different experience all together (of course, still a color experience).

This still is not surprising from a neuro perspective. Two people will never have neural connections formed in the same way and will always process information slightly differently.

However, they are still very similar. We all perceive color in the same generalized way. For instance (assuming a normal, healthy developed brain) some of us don't feel pain pain when we see red, while some of experience the taste of beef jerky.

 

[madness]

"That would be difficult to refute since we have no way of measuring experience yet, but is their any logical reason to believe that or was it pulled out of the air? For instance, why would it be another color of mine they experienced? Why not a completely different experience all together (of course, still a color experience)."

It was just an example, and I did say it could be a colour the other person couldn't even imagine in the earlier post. There is no logical reason to back it up, all I was saying is that it is conceivable and a valid question - the OP seemed to be arguing otherwise. I pretty much agree with the rest of your post.

 

[Pythagorean]

"That would be difficult to refute since we have no way of measuring experience yet, but is their any logical reason to believe that or was it pulled out of the air? For instance, why would it be another color of mine they experienced? Why not a completely different experience all together (of course, still a color experience)."

It was just an example, and I did say it could be a colour the other person couldn't even imagine in the earlier post. There is no logical reason to back it up, all I was saying is that it is conceivable and a valid question - the OP seemed to be arguing otherwise. I pretty much agree with the rest of your post.

Fair enough. I was genuinely curious about where this conception/question comes from, logically. It's a very common topic amongst philosophers, but I don't know it's origins.

 

[madness]

I would think it's more of a starting point for discussing the difference between perceptions/qualia and things like p-zombies. Just the fact that it's conceivable is interesting in this regard. I'm not sure if it's considered an important question in itself though.

 

[octelcogopod]

Joe said it earlier in the thread.. The color issue has very little to do with if we all can perceive color differently in itself, but rather goes deeper into the subjective nature of consciousness and observation.

Light does not contain the vivid experience we have when we see a color, and of course it seems obvious to me that we can all have different experiences.
But the real problem is "where" and "how" is this qualia created?

You don't even have to use colors, you can use any example.

Another example is touch and feeling on the skin/body.
When I pinch my arm the skin is folded and nerves/tissue is moved around, but nowhere in this physical composition is there contained the actual sensation/pain I feel.
This sensation is an experience my brain is giving me based on the information it receives, but you can't objectively measure or feel/see the pain in any lab tests.
Same as the experience of color. We can't even explain it to others.

The most fundamental issue is that there is no difference between a machine with no consciousness built exactly as a human, and a human as we know it.
There is no way to prove that consciousness exists, or that subjective experience exists, from a third person perspective.
When I first discovered this it was mindboggling, but hey, that's what reality is.

 

[Pythagorean]

Another example is touch and feeling on the skin/body.
When I pinch my arm the skin is folded and nerves/tissue is moved around, but nowhere in this physical composition is there contained the actual sensation/pain I feel.
This sensation is an experience my brain is giving me based on the information it receives, but you can't objectively measure or feel/see the pain in any lab tests.
Same as the experience of color. We can't even explain it to others.

Well, the nerves/tissue don't just move around. A signal actually propagates from the point of contact (on the skin) through transduction. It becomes an electrical symbol and travels to the brain (through both chemical and electrical signals, of course).

You say that nowhere there (in the physical composition) contained is the actual sensation/pain you feel. I would agree, but only because it is through a physical event that sensation/pain is felt. Velocity is a similar event. It's not the material itself, but a description of the current state of the material.

I propose that we (the scientific community) are very close to being able to measure things like pain and sensation. One way we already can do so is by measuring the neural activity. In a very simplified view, more pain would mean more neural activity.

But we still have the problem of qualia, of course: How do we tell pain from pleasure? Even if we can measure the intensity of these things, what's the difference. Just like anything in science, this comes from definition. We can't "measure" the difference between distance and velocity, they're simply defined as two different types of things. In the case of pain and pleasure, the type of qualia would be defined by the neural events that take place in each case (i.e. we induce pain into the subject and we see what circuitry lights up in the brain, then we induce pleasure into the subject and map out the different circuitry).

My hypothesis is testable too. If we find that only a certain kind of "circuitry" produces a certain experience, then we should be able to eliminate that experience by physically eliminating that circuitry from the brain. We already know beyond a doubt, that certain regions of the brain are responsible for different functions. This wouldn't be but a step beyond that. We just have to wait for brain imaging to catch up (which it seems to be doing with things like fMRI).

The most fundamental issue is that there is no difference between a machine with no consciousness built exactly as a human, and a human as we know it.

This is a fallacious argument, though. If you were able to build a machine exactly like a human, then it would be a human.

Also, see Daniel Dennet's criticisms on the P-Zombie:

[physicalists] argue that while consciousness, subjective experiences, and so forth exist in some sense, they are not as the zombie argument proponent claims they are; pain, for example, is not something that can be stripped off a person's mental life without bringing about any behavioral or physiological differences.

http://en.wikipedia.org/wiki/Philosophical_zombie#Criticism

 

[octelcogopod]

This is a fallacious argument, though. If you were able to build a machine exactly like a human, then it would be a human.

Also, see Daniel Dennet's criticisms on the P-Zombie:

[physicalists] argue that while consciousness, subjective experiences, and so forth exist in some sense, they are not as the zombie argument proponent claims they are; pain, for example, is not something that can be stripped off a person's mental life without bringing about any behavioral or physiological differences.
http://en.wikipedia.org/wiki/Philosophical_zombie#Criticism

But the reaction to pain can be programmed and then the person would react just as a person who actually feels pain. I don't see how that negates the zombie argument.
He is thinking on a very high level, you have to think on a very low level in that every molecule in the body is custom built for the sole purpose of creating a 100% identical zombie.

And yes, you would have a human, but you wouldn't know if it actually feels anything or is conscious, and this is true for our very reality as well. Prove to me that I am conscious.

 

[Pythagorean]

But the reaction to pain can be programmed and then the person would react just as a person who actually feels pain. I don't see how that negates the zombie argument.

Because if you're programming reactions in, you're not dealing with a human being. It's as simple as that. You're (more or less) talking about a robot that emulates humanity on the surface. You haven't built it to be exactly like a human.

He is thinking on a very high level, you have to think on a very low level in that every molecule in the body is custom built for the sole purpose of creating a 100% identical zombie.

Which would be impossible to do. If you could exactly replicate a human physically, it would be a human in every way.

And yes, you would have a human, but you wouldn't know if it actually feels anything or is conscious, and this is true for our very reality as well. Prove to me that I am conscious.

Based on your posting and replies, I can say with 100% certainty that you're not a troll-bot and actually a real human being with consciousness. You respond to my inquiries and arguments in a unique way that requires thinking about the material from an experienced point of view. An official proof of this would take lots more time and energy than I'm willing to invest (especially since I'm confident in my conclusion, and to me the physicalist view is rather self-evident).

You won't find any AI programs that can do this the degree and magnitude you do. Your individual way of replying and responding is set out by the context in which you learned the words themselves and the abstract philosophical concepts. No one else in the universe shares this collection of experiences with you. Without seeing your post, there is no way your post can be replicated from scratch.

Consciousness was required for your reply, starting with receiving my message (the input) down to the way you replied (output). What happened in the middle (the operation) required consciousness.

 

[octelcogopod]

Here's the problem as I see it:

There's no way to really define consciousness in a physical manner. We can define it subjectively by using normal language and words like 'thinking' 'abstraction' 'processing' 'feelings' but none of this can be proven to exist in the physical world.
The only reason we can map a brain event to an emotion, is because we know the emotion ourselves. When a subject laughs because of stimuli to the brain, we /assume/ that the subject has the same experience we do.

In fact, you're kind of the one implying dualism in the sense that you are telling me I have consciousness when there is no physical proof for it.
The only thing I'm trying to say is, there is a gap between perceiving conscious action, like laughter, reasoned speech and there actually being a conscious action.
This is not because I believe consciousness doesn't exist, but rather because so far nobody has been able to define consciousness, nor any subjective side to it.

I'm having a hard time coming to some kind of conclusion about what exactly a conscious experience is. Especially since in theory, you can never see a first person perspective from a third person one.
Conscious action implies first person experience, but in your post you are only deducing that first person experience must exist to exhibit that behavior, you haven't actually proven that it's there. And I don't know a way to do that.

Maybe science one day will solve all this, but who knows.

 

[Pythagorean]

There's no way to really define consciousness in a physical manner. We can define it subjectively by using normal language and words like 'thinking' 'abstraction' 'processing' 'feelings' but none of this can be proven to exist in the physical world.

It is difficult, but not impossible. See Kristof Koch, a neuroscientist:

Here's a course he teaches on the neuronal basis of consciousness
http://www.klab.caltech.edu/cns120/wiki/Main_Page

He also has done a lot of research in the field of consciousness from a neuronal perspective. Though, I can't deny that he himself has trouble defining it.

The only reason we can map a brain event to an emotion, is because we know the emotion ourselves. When a subject laughs because of stimuli to the brain, we /assume/ that the subject has the same experience we do.

Yes, it is an assumption. All science follows from assumptions. It's an assumption that doesn't contradict the study of the material so far though. It's been shown to be a good assumption.

In fact, you're kind of the one implying dualism in the sense that you are telling me I have consciousness when there is no physical proof for it.

I am absolutely anti-dualist. The real physical proof would be to fMRI my brain while I'm experiencing an emotion, then fMRI your brain while your giving the signs. If the activity is in the same region with the same characteristics, I'm convinced. There are different kind of neurons involved here. One set of neurons will squish your face up cause tearing and make all the visual cues, but the other set of neurons (between input and output) are the ones we're interested in. So yes, you may have the surface signs without having the experience, but there is an obvious physical difference in neural activity between someone only using neurons to manipulate his facial expressions, and someone actually experiencing emotion.

Conscious action implies first person experience, but in your post you are only deducing that first person experience must exist to exhibit that behavior, you haven't actually proven that it's there. And I don't know a way to do that.

Maybe science one day will solve all this, but who knows.

True, I used deduction. The deduction is based on the assumption that our fMRI's will reveal the same processes. The final proof is removing the circuitry from your own brain and seeing if you still have the experience. Physically falsifiable, but ethics and methodology are going to make the technology jump through hoops before it can be used with accuracy.

 

[Q_Goest]

But we still have the problem of qualia, of course: How do we tell pain from pleasure? Even if we can measure the intensity of these things, what's the difference. Just like anything in science, this comes from definition. We can't "measure" the difference between distance and velocity, they're simply defined as two different types of things. In the case of pain and pleasure, the type of qualia would be defined by the neural events that take place in each case (i.e. we induce pain into the subject and we see what circuitry lights up in the brain, then we induce pleasure into the subject and map out the different circuitry).

My hypothesis is testable too. If we find that only a certain kind of "circuitry" produces a certain experience, then we should be able to eliminate that experience by physically eliminating that circuitry from the brain. We already know beyond a doubt, that certain regions of the brain are responsible for different functions. This wouldn't be but a step beyond that. We just have to wait for brain imaging to catch up (which it seems to be doing with things like fMRI).

I have to go along with oct’pod on this. Consider for example, that we could easily rewire your circuits. Since Dennett is a favorite, let’s quote his work from “http://ase.tufts.edu/cogstud/papers/quinqual.htm" ”:

With eyes closed I accurately report everything you are looking at, except that I marvel at how the sky is yellow, the grass red, and so forth. Would this not confirm, empirically, that our qualia were different? But suppose the technician then pulls the plug on the connecting cable, inverts it 180 degrees and reinserts it in the socket. Now I report the sky is blue, the grass green, and so forth. Which is the "right" orientation of the plug? Designing and building such a device would require that its "fidelity" be tuned or calibrated by the normalization of the two subjects' reports--so we would be right back at our evidential starting point. The moral of this intuition pump is that no intersubjective comparison of qualia is possible, even with perfect technology.

So according to Dennett, we can easily rewire a brain to experience yellow instead of blue or red instead of green. That’s a great observation. I don’t doubt it for a second! In block diagram, it would look something like this:

INPUT --- COMPUTATION --- OUTPUT

So the input comes in, but according to Dennett, he screws the plug around 180 degrees and suddenly the greens turn to red and the blue turns to yellow. Let’s designate it like this:

INPUT –x- COMPUTATION --- OUTPUT

The x in between INPUT and COMPUTATION symbolizes the rotation of the ‘plug’ by 180 degrees.

Now let’s take Dennett’s “intuition pump” one step farther. Let’s cross the output wires. Now it looks like this:

INPUT –x- COMPUTATION –x- OUTPUT

Now every time you see blue, the inputs come in 180 out of sync and you actually experience yellow. Similarly, the greens get experienced as red. But we’ve also changed the output such that we say we’ve experienced blue when experiencing yellow and say green when we experience red.

I’m sure Dennett couldn’t argue this is problematic. We’re just following his lead.

Now we do the same for pleasure and pain. “OUCH. She kissed me.” (Hate when that happens.)

Input should produce pleasure, but the connector was rotated 180 degrees and the computation produced pain. Output gets swapped and we say we enjoyed the kiss.

What does this say about determining the experience we have by monitoring the behavior of the computational circuit? It says we have no way of telling what qualia was being experienced. Which actually, is exactly what Dennett wants you to believe when he says:

So contrary to what seems obvious at first blush, there simply are no qualia at all.

The point is that we can’t determine what qualia is being experienced by observing behavior. We can only determine what physical comings and goings are occurring within the brain, and the only way we can correlate qualia with those physical occurances is to make the assumption that the experiences are being reliably reported. But as shown here, we can’t know if the experiences are being reliably reported. People may be wired differently, and we couldn't know. One person may experience such qualia as color entirely differently than another person. There is no way to distinguish what qualia is experienced simply by examining the circuitry.

I think where the problem in this logic arises is in the basic, unspoken assumptions. We assume computationalism is true and this guides the logic.

 

[octelcogopod]

Pythagorean,

Regarding the fMRI example.. The problem still remains that there are certain non physical elements to the experience itself.
Or at least, the experience is a composition of many different physical elements but there is no single place to observe this experience from a third person perspective.
People always use the analogy "signal to the brain", which assumes that the signal is interpreted, but in a purely physical world, it can't be.

I pinch my arm, signals are sent to the brain, we can measure all this, but then at some point, there arises an actual experience, the feeling the individual has, and this resides nowhere in the brain.
So when you say your fMRI example, you're not really debating consciousness, you're debating the physical properties of the brain and body.
We're nowhere closer to actually grasping what subjective experience is, we just presume it exists.

 

[Pythagorean]

What does this say about determining the experience we have by monitoring the behavior of the computational circuit? It says we have no way of telling what qualia was being experienced.

But I see something different in the rest of your post. You've made physical changes to the system that have brought about changes in qualia. So far, this supports my point (though, I must say that from a neural circuitry point of view, your example is terribly oversimplified; especially the way you compare emotions to color sensation, but I will humor your for the thought experiment.)

Regardless, you have helped me to make my point. Now all we need is the technology that can see the connections. Then with a statistical empirical method, we go in and look at the connections and all the propositions that you made in your post (since, as you've argued, their is a physical basis for the changes in qualia. Our device is designed to "see" whether the cables are flipped 180 degrees).

Now we go a step further with our advanced alien laser cutter/manipulator and "flip the cable 180 degrees" ourselves. We can then measure the outcome (through statistical empirical methods of course, we can't trust one sample) and begin to build a model of the brain.

(By the way, I don't agree with Dennet that there is no qualia. My stance is that there is a physical basis for it).

Or at least, the experience is a composition of many different physical elements but there is no single place to observe this experience from a third person perspective.

This is what seems to be the case. But this does not make the problem impossible to approach scientifically. It makes it very, very difficult (which is why you'll have to be patient and wait about x years to test my conclusion, where I hope x is a number of years smaller than the years I have left). It calls for creative thinking on the scientists part, but it will not discourage my pursuit of consciousness through scientific venues.

 

[Pythagorean]

By the way, here's a post on another forum from a medical student that will help give you a better understanding of neural activity and will hopefully show why your (Qgoest) and Dennet's thought experiments are grossly oversimplified.

http://iwforums.com/showpost.php?p=554750&postcount=140

addendum:
Kristof Koch's Neuronal Basis of Consciousness:
http://www.klab.caltech.edu/~koch/Elsevier-NCC.html

 

[octelcogopod]

I don't think anyone can deny qualia. Qualia is the very essence of the subjective experience.
It is what makes us alive, rather than machines. IMO.

This vivid completely lucid and conscious experience which can actually be FELT in a very real and physical way is what is annoying me about the whole physicality problem.
This vivid experience is nowhere to be found in the physical world.
Intuitively my brain is asking me "why isn't there a single place in the brain where it all comes together, a physical single point that is the accumulation of all the brain activity and sensations?"

Because consciousness certainly feels like a single point. It feels like it is all accumulated into a coherent whole, where I am completely oblivious to the physical works underlying it.
I do not feel neurons, or nerves, or electromagnetic light frequencies, or chemicals, I feel happy, sad, excited, but where are all these things in the physical world?

I am actually not trying to imply dualism, and I feel probably that it is all physical in some way, but like you said, I actually feel done debating this problem and I am also waiting for further scientific progress by the bright minds working in neuroscience and other areas.

 

[Pythagorean]

Because consciousness certainly feels like a single point. It feels like it is all accumulated into a coherent whole, where I am completely oblivious to the physical works underlying it.
I do not feel neurons, or nerves, or electromagnetic light frequencies, or chemicals, I feel happy, sad, excited, but where are all these things in the physical world?

Hrm... To me it feels much different (of course, this is the subjective nature of qualia which arises from the way we learn and store memories). I feel like a product of many different functions happening at once. Sometimes I catch myself in one of these sub-processes (i.e. I become conscious that I'm just being jealous or spiteful and my intellect comes in and has a little conversation with my emotions, but then my hormones are blaring off about how we need to reproduce and the other two need to just shut up and let him do his job or face the eminent death of life on Earth (well, at least my strain of it). I'm also hearing and seeing things the whole time that are more in the background. I'm not thinking about every shape I see or considering the usefulness or meaning of it, I'm just recognizing what it is, doing a little check, being 'aware' of my surroundings. I'm conscious of all this: but each piece of information has a different ranking. At the forefront is the stream of consciousness. This seems to be the main "stuff" of consciousness to me. It is anything but coherent in the long run. It may have moments of coherency, but it seems more like a random reflection of my past experiences.

 

[Q_Goest]

Hi Pythagorean. My apologies in advance for the length. Note that in the following, I’ll be using a fundamental assumption that both you and Dennett appear to agree on, that being computationalism. That is, that the interactions of neurons is what produces the emergent properties of conscious experience. If we accept this, then I believe the rest of Dennett’s paper, Quinning Qualia, can logically follow from that. If we were to base our science of consciousness on something other than computationalism, then Dennett’s paper may or may not apply. I mention this because I think it’s important to understand the basic assumptions that go into an argument such as Dennett provides because different assumptions often lead to different conclusions, and the conclusions Dennett comes to seem to indicate there’s a fundamental flaw in our notions of what conscious experience is. I agree with his conclusion given his unwritten assumptions, but would disagree with his unwritten assumptions.

But I see something different in the rest of your post. You've made physical changes to the system that have brought about changes in qualia. So far, this supports my point … Now all we need is the technology that can see the connections. Then with a statistical empirical method, we go in and look at the connections and all the propositions that you made in your post (since, as you've argued, their is a physical basis for the changes in qualia. Our device is designed to "see" whether the cables are flipped 180 degrees).

Now we go a step further with our advanced alien laser cutter/manipulator and "flip the cable 180 degrees" ourselves. We can then measure the outcome (through statistical empirical methods of course, we can't trust one sample) and begin to build a model of the brain.

I understand how you came to your conclusion and I would agree that it’s logical. I’ve not done a very good job representing Dennett I’m afraid. I’ll try once more.

What you’ve pointed out by suggesting we can correlate the connections to the experience is exactly what Dennett is arguing against. Here’s how he introduces this paper:

My claim--which can only come into focus as we proceed--is that conscious experience has no properties that are special in any of the ways qualia have been supposed to be special.

He’s going to claim that qualia and experience of things such as red or pain do not have properties that are as we perceive them. That’s what he means by experiences not being special. Specifically, he means there are certain assumptions we make about our own experiences that do not coincide with a logical analysis of those experiences. Those assumptions he outlines as follows:

So, to summarize the tradition, qualia are supposed to be properties of a subject's mental states that are

(1) ineffable

(2) intrinsic

(3) private

(4) directly or immediately apprehensible in consciousness

The key property I’d like to focus on is the second one, “intrinsic”. This is the property you are also taking at face value. Your assumptions seem to indicate that you feel your experiences are intrinsic. There is an intrinsic correlation between the computation and what is experienced. Intrinsic in the sense that the correlation is intrinsic to nature. Every time that particular computation is performed, the experience will follow, and be supervenient on that physical substrate that is performing the computation. So when we flipped the plug 180 degrees, then if we believe the computation is intrinsic, then we believe that with this reversed input, the experience will also be flipped.

Now let’s go back to the thought experiment. This:
INPUT --- COMPUTATION --- OUTPUT

Produces the same output for any given input as this:
INPUT -x- COMPUTATION -x- OUTPUT

Similarly, we must also assume that every person has a slightly different computation going on inside their brain. So let’s say person 1 has this:
INPUT --- COMPUTATION(1) --- OUTPUT

And person 2 has this:
INPUT --- COMPUTATION(2) --- OUTPUT

Where COMPUTATION(1) is not equal to COMPUTATION(2). We can safely assume this because of multiple realizability. None of our brains are identical, but if we want to believe that qualia are intrinsic, then we must accept that my red is the same experience as your red. Now how many different people are possible? There are roughly 7 billion people on the Earth today and I’m guessing billions more who have already passed away. I don’t know how many different people there could possibly be, but I’m guessing it is many orders of magnitude larger than 7 billion, resulting in there being hundreds of billions or perhaps millions of billions of computations that produce the same intrinsic experience of a given color. And if we believe that a small, evolutionary step backwards or forwards does not change the experience, then we have to assume that there are also an array of different brains such as Cro-Magnon, Neanderthal and perhaps Orangutan brains must also experience the same intrinsic qualia that we homo sapiens experience. We could continue to extend this to other animals, so the number of different brains that potentially produce the same experience of the color red for example, must begin to approach an insanely huge number. If qualia are intrinsic, then we have to accept that the number of different computations that will produce the same experience is huge. I won’t say infinite, because I can’t be sure of that.

To make matters worse, each brain is also plastic, rewiring itself as time proceeds. Yet even with this rewiring, if qualia are intrinsic, then the these new computations that are taking place as time goes on, must also produce the same experience inside the same, rewired brain. This includes rewiring of inputs and outputs.

Next, I’d like to suggest that there could be identical computations that produce different qualia. Let’s take a simple example. Experimenters have taken rat neurons and grown them inside Petrie dishes on top of electrical arrays that allow the neurons to interact with electrical impulses from this two dimensional array. In one example, the neurons were made to ‘fly’ an aircraft (flight simulator inside a computer) straight and level. The way this was done isn’t that hard to understand. They were able to influence how the neurons reacted by inputting signals at different points on this array over which this sheet of neurons were grown. Then they would monitor the outputs/interactions and took the output they needed to get the flight simulator to fly straight and level. They could have equally made those same outputs make the simulator fly perfect barrel rolls or loops. They could equally have used those same outputs to control stop lights in a large city, or controlled the processes in an air separation plant, or the flights between various major cities. They were in no way forced to take these outputs and only fly this particular flight simulator straight and level with them. The outputs could have produced any infinite number of different phenomena. In other words, for any given computation, we can take that computation and use it for any output whatsoever. The output is not restricted to any special output that only that particular computation can produce. There is no 1 to 1 correlation between a computation and the use of the output for that computation. And the same can be said for the input. That input didn’t need to come from the experimenter’s computer. It could have come from the pressure and temperature transducers located around an air separation plant. Or they could have come from the change machine and timers in a laundrymat. The input isn’t intrinsic to the computation in any meaningful way.

Now we put these two together. There are all these different computations that produce the same qualia. And any given computation can be made to do any number of different things given a specific input and output. This seems to indicate that there is nothing intrinsic about a computation such that there exists a 1 to 1 relationship between a given experience and the computation on which that experience supervenes.

Dennett argues that there is nothing intrinsic to qualia and comes to the same conclusion, though he uses ‘intuition pumps’ to try and convince you that he’s right. I guess I don’t accept his ‘intuition pumps’. I agree with his conclusions however where he states:

So when we look one last time at our original characterization of qualia, as ineffable, intrinsic, private, directly apprehensible properties of experience, we find that there is nothing to fill the bill. In their place are relatively or practically ineffable public properties we can refer to indirectly via reference to our private property-detectors-- private only in the sense of idiosyncratic. And insofar as we wish to cling to our subjective authority about the occurrence within us of states of certain types or with certain properties, we can have some authority--not infallibility or incorrigibility, but something better than sheer guessing--but only if we restrict ourselves to relational, extrinsic properties like the power of certain internal states of ours to provoke acts of apparent re- identification. So contrary to what seems obvious at first blush, there simply are no qualia at all.

I should clarify my interpretation of that last sentence. Dennett doesn’t seem to mean that qualia don’t exist as we might literally take that sentence. He means they can’t be intrinsic, among other things. He’s saying that qualia can’t have the properties we perceive them as having. He’s saying one person’s experience of red for example, can’t be the same, seemingly stable experience every day forever and that those qualia in general must vary depending on what computation is being performed. There is nothing special (intrinsic to nature) about a given qualia.

 

[Pythagorean]

Hi Pythagorean. My apologies in advance for the length.

Good evening Q_Goest, no worries about the length. I welcome your comments.

Note that in the following, I’ll be using a fundamental assumption that both you and Dennett appear to agree on, that being computationalism. That is, that the interactions of neurons is what produces the emergent properties of conscious experience.

I'm reluctant to label myself that specifically yet. I don't completely understand computationalism yet. There are definitely aspects of computation I agree with (especially what you mentioned above). But the definition you gave above is only one defining aspect of computationalism. Alone it seems to be a narrow view of physicalism.

I say narrow because it's not necessarily neurons doing all the work. Neuroscience is more recently beginning to recognize the role glial cells play (says my neurobiology instructor; I always thought they were merely a support system myself) though it's new enough not to be in our textbook.

We do know that we can represent a neuron with an equivalent circuit. But I don't have any reason to think that this is the only important aspect of what's going on (though, we must admit that it plays a significant role).

What I can say about computationalism is that the brain seems to be very well capable of it. But does that mean it's limited to it? I don't think so. At least, not in the traditional input/output sense.

I mention this because I think it’s important to understand the basic assumptions that go into an argument such as Dennett provides because different assumptions often lead to different conclusions, and the conclusions Dennett comes to seem to indicate there’s a fundamental flaw in our notions of what conscious experience is.

We agree on this. As Dennett said in one of his presentations "Everybody thinks they're an expert on consciousness". Everyone has their definition.

Kristof Koch agrees. One of the way he is confronting that problem is by proposing several different kinds of consciousness that exist simultaneously in a single brain.

Specifically, he means there are certain assumptions we make about our own experiences that do not coincide with a logical analysis of those experiences. Those assumptions he outlines as follows:

Just an FYI. I can only comment on the ones you comment on as I haven't heard of Quinning Qualia and I'm not completely sure of the way those terms are going to be applied to consciousness or your interpretation of it until you open discussion about it. Obviously, "intrinsic" alone doesn't tell me much, since I've used that term in a number of different ways in my undergrad degree, but since you've extrapolated here:

Intrinsic in the sense that the correlation is intrinsic to nature. Every time that particular computation is performed, the experience will follow, and be supervenient on that physical substrate that is performing the computation. So when we flipped the plug 180 degrees, then if we believe the computation is intrinsic, then we believe that with this reversed input, the experience will also be flipped.

If you read my links, you might understand why I view this is a harmful (in terms of productive discussion) oversimplification. It assumes a reversible connection... I don't know what this correlates to neurally, or if it's even a valid correlation of anything in the neural sense.

Now let’s go back to the thought experiment. This:
INPUT --- COMPUTATION --- OUTPUT

Produces the same output for any given input as this:
INPUT -x- COMPUTATION -x- OUTPUT

Similarly, we must also assume that every person has a slightly different computation going on inside their brain. So let’s say person 1 has this:
INPUT --- COMPUTATION(1) --- OUTPUT

And person 2 has this:
INPUT --- COMPUTATION(2) --- OUTPUT

Where COMPUTATION(1) is not equal to COMPUTATION(2). We can safely assume this because of multiple realizability. None of our brains are identical, but if we want to believe that qualia are intrinsic, then we must accept that my red is the same experience as your red. Now how many different people are possible? There are roughly 7 billion people on the Earth today and I’m guessing billions more who have already passed away. I don’t know how many different people there could possibly be, but I’m guessing it is many orders of magnitude larger than 7 billion, resulting in there being hundreds of billions or perhaps millions of billions of computations that produce the same intrinsic experience of a given color. And if we believe that a small, evolutionary step backwards or forwards does not change the experience, then we have to assume that there are also an array of different brains such as Cro-Magnon, Neanderthal and perhaps Orangutan brains must also experience the same intrinsic qualia that we homo sapiens experience. We could continue to extend this to other animals, so the number of different brains that potentially produce the same experience of the color red for example, must begin to approach an insanely huge number. If qualia are intrinsic, then we have to accept that the number of different computations that will produce the same experience is huge. I won’t say infinite, because I can’t be sure of that.

I think we can be sure that it's infinite, since we're capable of recursive operations. However, this doesn't concern me since it's not the individual signals themselves that matter, it's the classification of signals.

"You never cross the same river twice.".

In the same way, you never listen to the same set of audio signals twice. You may play a song twice in a row, and recognize it as the same song, but because of the inherent non-linearity of the real world, you'll never receive the signal in the exact same way.

But this is fine! We have an excellent classification and generalization system in terms of computation. It also leads to problems, of course (stereotyping and prejudicing, faulty assumptions when comparing things that are have similarities... such as the gravitational and electromagnetic fields for example).

I have some suggestive evidence that colors are, in fact, intrinsic. The obvious example is black and white. If you do not agree, I will extrapolate, but I assume most philosopher who speak of qualia and color have an argument in their pocket for this since they never bring up black vs. white and the point seems to be self-evident to me. By not explaining it, I hope to prove it's self-evidence as well.

Here's my suggestive evidence:
Babies prefer the colors black, white, and red. They are drawn to them because of the contrast (in an anecdote way, I can confirm this as a father of two months now) between them. This is important to me. If everything was all one color, would we see color? I don't think we would even have a word for it. There would be no evolutionary purpose for sure. Perhaps the significance then, is in the comparison of one color to another.

Humans also tend to associated common emotional terms with colors:
red - anger and sex... intensity
black -depression
yellow - happiness (I've actually heard annoying here too
(more in the link)
http://en.wikipedia.org/wiki/Color_symbolism_and_psychology

Also, evolutionarily, the significance of color in nature allows animals to be afraid of poisonous things. It even allows animals that aren't poisonous to pretend they're poisonous (cuttle fish are one example).

The taste of sweetness signifies that something is good for you (remember this is evolutionarily... our taste buds haven't evolved to our modern day where sugar is mass produced enough to be bad for you. Sugar was much more rare in our evolutionary history)

To make matters worse, each brain is also plastic, rewiring itself as time proceeds. Yet even with this rewiring, if qualia are intrinsic, then the these new computations that are taking place as time goes on, must also produce the same experience inside the same, rewired brain. This includes rewiring of inputs and outputs.

Of course, this is fine in the sense of a neural network learning, classifying, and generalizing to create a world model based on its inputs.

I wouldn't say that they must produce the same experience, I would say the same class of experience. Also, are you sure that the plasticity occurs in the part of the brain where experience is concerned? Or is the plasticity a response to the experience? I.e., we remember to avoid negative experiences and do so by classifying and predicting them in future experiences. The way we react to the experience itself may change, (and so we have a new after-experience). For instance, we may feel disappointment that we managed to have the same crappy experience a second time.

But you can't conveniently choose where plasticity occurs for the purpose of your argument, especially when neuroscientists themselves don't know where consciousness "is" in the brain yet. Plasticity may not affect the base experience of a sensation, only the emotional reactions to that base experience. But even if it does, all that remains necessary for me is that the experience is of the same class.

As an aside, plasticity is reduced in a lot of the brain for adults. Strangely enough, our olfactory system is one of the regions of the brain where plasticity remains in adults. Of course we used to believe that all plasticity stopped in the adult brain, which we now know is not true. However, it's not near as plastic as the youth so I just want to make sure no one has gotten that impression.

It's late here now and I'm tired, so I should probably respond to the rest of your post at a later time, unless I've changed the direction of our debate in which case you'll want to reply to what I've already said so far.

Cheers,
Pythagorean

 

[Simon76]

Little random, and no particular reason, and this is probably a silly question...

If for example you're flooded by ultraviolet light - lots of it, as per typical nightclub, I'm told white glows brightly. Is ultraviolet a misleading name however? Would a person usually be left with a purple/blue blur / afterimage / tinge to everything, or only see white clothing glowing brightly?

I'm assuming the latter, as ultraviolet is invisible to the human eye?

Also, colour banding is gradual - might there be a wavelength used for some ultraviolet lights that happens to sit closer to the blue band and therefore may be weakly picked up by the eye?

(Same for infrared)

Thanks

 

[binbots]

Everyone may see there own versions of colour. When we all agree something is green, all we are agreeing on is the name of the colour green. But my green may look different than your green, but we both agree it is green. A persons truth to them is absolute truth.