jpbrooks

jpbrooks:

Not necessarily. As was pointed out above, materialism can be true even if yr is different from mr. Even within materialism, it can be argued that the way our sensory experiences appear to us could depend on the way that the neural patterns in our brains have developed individually over time as it is fed sensory information. (This phenomenon of neural pattern development in the brain may also account for our adaptation to changes in our visual field, [such as the "inversion" phenomenon pointed out by excreationist].)

I'm not certain that questions like this one can even be answered by examining sensory experience itself.
The answer appears to depend on whether the brain produces what we experience as mental phenomena, or whether there is some kind of immaterial "realm" where "centers" of consciousness reside that use the brain as a medium of communication with the material realm. I tend to favor the former theory of mental phenomena over the latter, but there seems to be no way to rule out the latter theory on the basis of sensory experiences alone.

-John Phillip Brooks

[ January 01, 2002: Message edited by: jpbrooks ]</p>

hedonologist

Actually, I should have said that is one reason we can't say for certain whether yr is like mr. You brought up another reason, which is objective, instead. The firing pattern is just like the wavelength in that it is just part of the physical component of the experience. No matter how much we know about the physical process, how could we ever know if yr was mr?
I'm not questioning whether yr is "real red" or mr is "real red", so long as you are not a zombie and thus see some "color". I'm questioning whether these colors are "material things" or "subjective things".
There is no question that the brain converts some objective info into a subjective experience. It doesn't matter whether it is a number or a wavelength.
I would like to try it for enlightenment. Maybe it would give insights into this subject.

Have you heard of the Persinger Helmet? It uses magnetism to induce "religious experiences", déjà vu, feelings of G-forces, etc. It seems more invasive, thus dangerous but maybe not so risky as a drug. <a href="http://www.innerworlds.50megs.com/#SHAKTI" target="_blank">http://www.innerworlds.50megs.com/#SHAKTI</a> It only costs $250 to be an experimental subject, and a history of mental illness will not necessarily disqualify you!

hedonologist

I wasn't saying exactly that if yr was different than mr that this would mean that materialism could not be true. What I meant is that if you can perceive yr (and you are not a zombie), aren't you perceiving something subjective? I'm saying you are believing/perceiving something that is not known to be material (color), and that can't be defined in terms of material. It can only be "personally defined" as the effect of a certain wavelength on your experience.
That "realm" is the (subjective) experience. You don't have to look for it, it is your experience.
If the former theory is just a material explanation of how yr could differ from mr, then they are not alternative theories. They explain different "things".

jpbrooks

quote:

Originally posted by jpbrooks

Not necessarily. As was pointed out above, materialism can be true even if yr is different from mr.

hedonologist wrote:

I wasn't saying exactly that if yr was different than mr that this would mean that materialism could not be true. What I meant is that if you can perceive yr (and you are not a zombie), aren't you perceiving something subjective?

jpbrooks:

Again, not necessarily.
If materialism is true then, in principle, "color perception" could be completely accounted for on the basis of material processes. This means that it would be, in principle, possible to build or program a machine to "experience" color as mr/yr and display that "experience" objectively.

hedonologist wrote:

I'm saying you are believing/perceiving something that is not known to be material (color), and that can't be defined in terms of material. It can only be "personally defined" as the effect of a certain wavelength on your experience.

jpbrooks:

I'm not sure how one could "personally define" color? What steps would be involved in the definition process?

quote:

Originally posted by jpbrooks

I'm not certain that questions like this one can even be answered by examining sensory experience itself.
The answer appears to depend on whether the brain produces what we experience as mental phenomena, or whether there is some kind of immaterial "realm" where "centers" of consciousness reside that use the brain as a medium of communication with the material realm.

hedonologist wrote:

That "realm" is the (subjective) experience. You don't have to look for it, it is your experience.

jpbrooks:

But there is no convincing evidence that human consciousness exists in a "realm" that can exist independently from the physical material world. It is just that this alternative cannot be ruled out on the basis of sensory experience.

quote:

Originally posted by jpbrooks

I tend to favor the former theory of mental phenomena over the latter, but there seems to be no way to rule out the latter theory on the basis of sensory experiences alone.

hedonologist wrote:

If the former theory is just a material explanation of how yr could differ from mr, then they are not alternative theories. They explain different "things".


jpbrooks:

But in that case, yr and mr also could no longer (in principle) be considered subjective.

[ January 02, 2002: Message edited by: jpbrooks ]</p>

Laurentius

AVE

Let us reduce the matter to three issues:
1.Is color an intrinsic property of objects?
2.Are colors purely subjective representations?
3.Does perception in general function on a purely subjective basis?

Question: Is color an intrinsic property of objects?
Answer: No, it is not.
A white object will be dark in a dark room, whereas its mass, chemical structure, etc. will not fluctuate in such manner.
Color is part of the way human sense the world through sight (electromagnetic wave generation, reflection, absorption, and stuff).

Question: Are colors purely subjective representations?
Answer: No, they are not.
Colors are representations of the electromagnetic flux analyzed by the sight apparatus. Except for a few, this apparatus has the same structure in all humans, and this is why different people identify red as being red, and this red is everybody’s red.
What remains subjective in all this story is the way people feel about red, their attitude. According to their past experiences, to the present mood, to future interests, people may find red attractive, repulsive, fashionable, vulgar, stimulating, annoying, etc.

Question: Does perception in general function on a purely subjective basis?
Answer: No, it does not.
Reception being optimal for two different subjects with comparably equal competence, they will identify sizes, weights, shapes, numbers, etc. in the same way.
The perception of a female by a male is highly objective. However, different males will identify correctly a female in a group of males, given the opportunity of optimal reception. On the other hand, how they will individually feel about that woman remains purely subjective.

hedonologist

How would you know whether the machine were seeing yr?
By experiencing them. You have some colors on your screen right? Look at the redness of the red. That is yr. Yr may be the same "color" as mb.
I'm not sure what you mean by independent. If experience is not independent of the material world, what does this say about yr? Does this mean that yr is "material" or that it "doesn't exist"?
I've realized that it is not just subjective experience which "disproves materialism", in a sense, it is any experience. Though, I'm not saying experience could exist without "matter". I'm back to the zombie hypothetical, which doesn't specify color, so I think I'm going to pose the question in another thread or post to an old one.

hedonologist

I don't think so. Wr has that same name for everybody but yr could look the same to you as mb looks to me, for all we know.
The feeling is subjective as well, but regardless of how yr makes you feel, yr could look like mb, so this "color" is subjective, as well.

excreationist

Another thing, there are other things that make up our experiences of colour rather than the sensation of seeing the colour....

e.g. say there is a homophobe who thinks that the colour pink is gay and totally repulsive when used by males. He might seen a man wearing pink pants and feel physically sick. Another person might be a little girl who loves the colour pink. Pink looks very beautiful to her.

"How would you know whether the machine were seeing yr?....You have some colors on your screen right? Look at the redness of the red. That is yr. Yr may be the same "color" as mb."

Well you'd need to get really precise brain analysing equipment to look at the exact firing patterns of your neurons. FF0000 (RGB red) and 00FFFF00 (CYMK red) are equivalent though they are represented in different ways. In the same way, 111 and 7 and 21 are equivalent (if the first is in binary, the second is at least octal or decimal and the third is trinary) but the representations are different.

So different people probably have different representations for colours since the brain is self-organizing and shaped by its idiosyncratic experiences. But the experience is still equivalent. (they both label the colour sensation from the same source "red" though the internal representation is probably different)

US$250 is way too expensive for me... apparently you can get inverted goggles custom-made for about US$30 - I'm trying to email a guy about it.

"I'm questioning whether these colors are "material things" or "subjective things"."

Well there is information in our brains where we associate idiosyncratic colour sensations with words. This mapping of colour sensations to words does exist physically, but it is "subjective" since it only is used by that person's brain...

jpbrooks

quote:

Originally posted by jpbrooks

If materialism is true then, in principle, "color perception" could be completely accounted for on the basis of material processes. This means that it would be, in principle, possible to build or program a machine to "experience" color as mr/yr and display that "experience" objectively.

hedonologist wrote:

How would you know whether the machine were seeing yr?

jpbrooks:

Assuming that materialism is true, one could, through a series of experiments on various individuals, determine what brain structures and processes give rise to corresponding 'color sensations". Once the brain has been completely mapped, then the machine can be constructed and/or programmed to display its "experiences".
In other words, any subjective differences between mr and yr could, if materialism is true, only be due to differences in brain structure or processing, since "mental states"` would be, in principle, completely reducible to brain states.


quote:

Originally posted by jpbrooks

I'm not sure how one could "personally define" color? What steps would be involved in the definition process?

hedonologist wrote:

By experiencing them. You have some colors on your screen right? Look at the redness of the red. That is yr. Yr may be the same "color" as mb.

jpbrooks:

I think I see what you are suggesting, but (again) I'm not sure that it establishes what you are attempting to establish.

First, definitions are "meanings", which cannot be confirmed to exist on a purely subjective basis. For example, how can you confirm that the mb that you are experiencing now is the same mb that you believe that you have experienced in the past that led you to believe that you could trust your memory? That is, within pure subjectivity, there is nothing outside of memory, which is the source of part of the experience, that can be used to confirm that one experience is the same, similar to, or different from another experience.

Second, even if the subjective experience yr is different from the subjective experience mr, that still doesn't establish that that difference is not the result of physical or material phenomena.

quote:

Originally posted by jpbrooks

But there is no convincing evidence that human consciousness exists in a "realm" that can exist independently from the physical material world. It is just that this alternative cannot be ruled out on the basis of sensory experience.

hedonologist wrote:

I'm not sure what you mean by independent. If experience is not independent of the material world, what does this say about yr? Does this mean that yr is "material" or that it "doesn't exist"?

jpbrooks:

By "independent", I meant that the "realm" in question does not depend on the existence of the material realm for its own existence, and is therefore, unlike an epiphenomenal "realm", able to produce effects in the material "realm".

quote:

Originally posted by jpbrooks

But in that case, yr and mr also could no longer (in principle) be considered subjective.

hedonologist wrote:

I've realized that it is not just subjective experience which "disproves materialism", in a sense, it is any experience.

jpbrooks:

No, subjective experience is compatible with both materialism and immaterialism.
"Mental events" can occur as subjective experiences even if they are all, in principle, reducible to brain states.

[ January 02, 2002: Message edited by: jpbrooks ]</p>

NialScorva

Ok, two points. As to whether color is an intrinsic property of matter, the answer is yes (if you find scientific enquiry a satisfactory definition of objective). The color of an object can be determined from it composite materials using quantum electrodynamics and Maxwell's equations. It's non-trivial, and we can only calculate simple molecules, but the equations work. Except for synesthesia and color blindedness, human retinas have basically the same response curves to color frequencies:

From a <a href="http://www.handprint.com/HP/WCL/color1.html" target="_blank">pretty neat page</a> on color perception.

So, everything from the object to the brain is pretty much objective for our purposes. The real meat of the question is the internal representation of these objects.

To answer the original question, though I don't consider myself a materialist, I would say that color itself is both non-material and consistent with materialism. As I've already shown, the sensory half of color is a property of matter, as objective as anything in our limited ability to approach objectivity. Within the mind, the question is whether the subjective qualia are material. I contend that they are representational rather than objects in and of themself. I refer you to the no-private-language argument, which rather than draw a conclusion from your type of question, showed it's not even a valid question:

Use emotion as an example. I feel an emotion, and call it *foo*. How do I make others know what that word means? My only option seems to be to look at their behavior and compare it to my own reactions. Similarly, if I call something *baz*, then you can only associate what I say with some behavior. Over time, you can figure out to associate *baz* with the color brown, and associate my use of the word *foo* with you being angry. To form a private language, I cannot perform any error correction, I've merely replaced one inexpressible qualia for another. Language is representational of something.

Representations may or may not objects themself, they refer to some antecedent object, which may or may not be material. With color, we obviously are using the word "blue" to refer to the qualia generated by a specific wavelength of light. However, this qualia is inexpressible except through a public language, and thus cannot be directly compared, not matter whether you are a pro-subjective anti-ontologist such as I, or a strict materialist.


As another arguement, this qualia could be considered representitive of the sensory experience, and as such does not need to be the same across all observers, so long as there is a consistent mapping from one to another. We may have different ways of seeing the same objective color, but we can show trivially that each member of your color qualia can be mapped to the set of visible light, and at least a major subset of that can be mapped into my color qualia. We can do the samething using linguistic rather than visual elements as the bridge. There is a mapping, and regardless of whether the qualias are equal, they can be mapped to one another. Similarly, those colors can be expressed in terms of hz, wavelength, and various color scales, or by various number systems, measurement systems (mm wavelength vs inches), on paper, pixels, or voxels. In any of these cases, the representation doesn't strictly exist, rather it's a pattern of things that exist. To deny that things can be represented in such a way by materialism would be denying that things such as movement and acceleration can be accounted for by materialism.