# Can color exist to a blind person?

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Consider this. Suppose we have an electronic deice that transduces color to sound. The bluer the color, the higher the pitch. The redder the color the lower the pitch. What we have is a sensory analog to color. This might suffice to give a blind person some idea of what color an object is.

We already do this with electromagnetic frequencies higher than the visible. We use what is called "color coding" or "false color" in which a visible color stand as s surrogate for a higher frequency electromagnetic radiation.

It might be of limited use to a blind person.

Ba'al Chatzaf

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Consider this. Suppose we have an electronic deice that transduces color to sound. The bluer the color, the higher the pitch. The redder the color the lower the pitch. What we have is a sensory analog to color. This might suffice to give a blind person some idea of what color an object is.

We already do this with electromagnetic frequencies higher than the visible. We use what is called "color coding" or "false color" in which a visible color stand as s surrogate for a higher frequency electromagnetic radiation.

It might be of limited use to a blind person.

Ba'al Chatzaf

Where would he 'aim' the device? What objects is he 'viewing'?

It's still a transposition of color to another medium, giving him 'blue', 'orange' -etc.

The pitch of sound differentiates colors and names them, but does color "exist" for him,

conceptually?

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Consider this. Suppose we have an electronic deice that transduces color to sound. The bluer the color, the higher the pitch. The redder the color the lower the pitch. What we have is a sensory analog to color. This might suffice to give a blind person some idea of what color an object is.

We already do this with electromagnetic frequencies higher than the visible. We use what is called "color coding" or "false color" in which a visible color stand as s surrogate for a higher frequency electromagnetic radiation.

It might be of limited use to a blind person.

Ba'al Chatzaf

Where would he 'aim' the device? What objects is he 'viewing'?

It's still a transposition of color to another medium, giving him 'blue', 'orange' -etc.

The pitch of sound differentiates colors and names them, but does color "exist" for him,

conceptually?

No, he wouldn’t. Color would be a construct of varying loudnesses of sound, but the individual would never understand “red”, etc., and how would a variety of colors sound?

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Would this be the one book you would recommend? Mind you I have little free time with 4 kids, 13 and under including 2 Russian sisters who arrived here 6 weeks ago and a corporate exec wife who works 60+hour weeks. Hence my cooking duties.

Mike,

It's a toss-up with The Six Pillars of Self-Esteem, but probably yes to the recommendation. This one (Consciously) is more theoretical in terms of consciousness than Pillars.

The Psychology of Self-Esteem is also a good one, but it is NB's first book and was written when he still called himself an Objectivist (however it was published right after he was banished to beyond the last rung of Objectivist Hell ). Most of the material first appeared in The Objectivist Newsletter and The Objectivist, so it does not present his mature work. Still, it's very good.

Michael

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Consider this. Suppose we have an electronic deice that transduces color to sound. The bluer the color, the higher the pitch. The redder the color the lower the pitch. What we have is a sensory analog to color. This might suffice to give a blind person some idea of what color an object is.

We already do this with electromagnetic frequencies higher than the visible. We use what is called "color coding" or "false color" in which a visible color stand as s surrogate for a higher frequency electromagnetic radiation.

It might be of limited use to a blind person.

Ba'al Chatzaf

Where would he 'aim' the device? What objects is he 'viewing'?

It's still a transposition of color to another medium, giving him 'blue', 'orange' -etc.

The pitch of sound differentiates colors and names them, but does color "exist" for him,

conceptually?

No, he wouldn’t. Color would be a construct of varying loudnesses of sound, but the individual would never understand “red”, etc., and how would a variety of colors sound?

The blind person using sound coding for color would build a perceptual model internally.

We sighted folks who use false color to represent invisible frequencies can build up correct relationships between frequencies. It is the abstract relationship between frequencies that can be internalized using false color coding. Similarly a blind person could develop a correct abstract concept of relationships between colors by using the pitch coding of color.

Blind people can store words from natural languages internally using braille which is a touch input encoding.

Humans are very clever at building concepts up from encoded input.

Ba'al Chatzaf

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I agree. Then the question becomes whether the blind person can think a seeing person irrational if he speaks of either sight or color.

And why not? We don't directly perceive X-rays but talk about them all the time. We function on conceptual, not perceptual level. Blind person could perceive visual information by using other senses. He cannot see letters but could read braille prints.

OK. I accept that a blind person can conceptualize information by other senses. in your case Braille prints as a form of written language, but my OP was about whether color can exist to a blind person.

"If the blind person then stated that color doesn't exist and anyone who believes there is such a thing as color is irrational, would he be correct? If not, how would you prove he was incorrect? "

Metaphysically speaking color doesn't exists at all. It has no existence outside of the realm of consciousness. It is an epistemic, not a metaphysical concept. So to speak about existence of color as independent entity is indeed wrong, irrational since color doesn't have a metaphysical status. However we perceive different colors because things have different properties. These properties could be perceived even by blind person by using different senses-as in Peter's example. We can explain then to the blind person that what he perceives in such a case as warm we perceive as white. The bottom line is that percepts belong to the realm of consciousness, not existence.

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Leonid wrote, "Metaphysically speaking color doesn't exists at all. It has no existence outside of the realm of consciousness. It is an epistemic, not a metaphysical concept. So to speak about existence of color as independent entity is indeed wrong, irrational since color doesn't have a metaphysical status. However we perceive different colors because things have different properties. These properties could be perceived even by blind person by using different senses-as in Peter's example. We can explain then to the blind person that what he perceives in such a case as warm we perceive as white. The bottom line is that percepts belong to the realm of consciousness, not existence."

Huh??? Are the trees really green if no one is there to look at them??? Color is objective and not dependent on consciousness to exist. Your statement reminds me of the question, "if a tree falls in the woods and no is there to hear it, does it make a sound?"

None of the answers presented so far have shown that color can be known to exist to a blind person. He simply lacks the apparatus to experience sight and color and must trust what others tell him. Yes, you could use heat, taste, touch, or sound as analogues to color and their differences, but 'color' still remains an unknown.

As MSK noted above, correctly in my opinion, there may be aspects of reality that we do not possess the sense organs to detect. We have to admit that "we don't know what we don't know" and therefore should not be dogmatic in those areas.

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If a person were totally blind, say born without eyes as one individual I knew years ago, can color or even the concept of color exist for that person?

Yes, the concept of color can exist for that person. As has been pointed out by others, we need not directly perceive something to be aware of its existence and to determine its characteristics. There are all sorts of things that we can conceptualize despite not being able to perceive them directly.

If a blind person uses a cane to detect where the sidewalk is, would you say that he's not actually knowing the existence of the sidewalk because he's not touching it directly? We use tools to expand, enhance and combine the power of our senses so as to know things that we wouldn't if we had to rely on any one single sense.

I don't mean simply a definition of color as reflection of light, or a description of light as a measurement of wavelength along the electromagentic spectrum, etc. I mean the redness of red or the brownness of brown, etc.? I would assume not, as this is outside of his nature (i.e., total blindness)

Correct. A blind person cannot see. Those who can't see can't experience the visual redness of red.

If the blind person then stated that color doesn't exist and anyone who believes there is such a thing as color is irrational, would he be correct?

No.

If not, how would you prove he was incorrect?

We'd prove it by the means already suggested by others. We'd set up equipment which measures colors (and converts the information to, say, numerical values) in a controlled environment in which the blind person could witness us accurately detecting the colors without such equipment.

J

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If a person were totally blind, say born without eyes as one individual I knew years ago, can color or even the concept of color exist for that person?

Yes, the concept of color can exist for that person. As has been pointed out by others, we need not directly perceive something to be aware of its existence and to determine its characteristics. There are all sorts of things that we can conceptualize despite not being able to perceive them directly.

We'd prove it by the means already suggested by others. We'd set up equipment which measures colors (and converts the information to, say, numerical values) in a controlled environment in which the blind person could witness us accurately detecting the colors without such equipment.

J

"There are all sorts of things that we can conceptualize despite not being able to perceive them directly."

Could the same be said about God?

The rest I agree with. i.e., an analogue could be constructed to attempt to identify color, but the person would still never experience color.

Sorry for the lousy use of the quote fxn.

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If a person were totally blind, say born without eyes as one individual I knew years ago, can color or even the concept of color exist for that person?

Yes, the concept of color can exist for that person. As has been pointed out by others, we need not directly perceive something to be aware of its existence and to determine its characteristics. There are all sorts of things that we can conceptualize despite not being able to perceive them directly.

We'd prove it by the means already suggested by others. We'd set up equipment which measures colors (and converts the information to, say, numerical values) in a controlled environment in which the blind person could witness us accurately detecting the colors without such equipment.

J

"There are all sorts of things that we can conceptualize despite not being able to perceive them directly."

Could the same be said about God?

The rest I agree with. i.e., an analogue could be constructed to attempt to identify color, but the person would still never experience color.

Sorry for the lousy use of the quote fxn.

LOL! Very neat, Mike. I was wondering if you'd go there...

"Could the same be said for God?" ha!

Color is one characteristic of an entity, I believe. White light on it absorbs certain wavelengths, and reflects others.

Therefore, color exists independently of the viewer. The (green) tree does indeed make a sound when it falls in the forest.

For the concept "color", one has to have a referent in reality - sensory and perceptual. A 'concept' that by-passes these - must be rationalistic. i.e, It's a floating abstraction, with no pertinence to reality, for a blind person.

Ba'al's "device" creates another concept entirely, stemming from the aural cortex - not the visual. (Same for Braille, and touch.) One could probably describe the form of a tree to a blind man; but describe a color? No way.

Could just as well be describing Beethoven's Fifth to a deaf man.

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If a person were totally blind, say born without eyes as one individual I knew years ago, can color or even the concept of color exist for that person?

Yes, the concept of color can exist for that person. As has been pointed out by others, we need not directly perceive something to be aware of its existence and to determine its characteristics. There are all sorts of things that we can conceptualize despite not being able to perceive them directly.

We'd prove it by the means already suggested by others. We'd set up equipment which measures colors (and converts the information to, say, numerical values) in a controlled environment in which the blind person could witness us accurately detecting the colors without such equipment.

J

"There are all sorts of things that we can conceptualize despite not being able to perceive them directly."

Could the same be said about God?

The rest I agree with. i.e., an analogue could be constructed to attempt to identify color, but the person would still never experience color.

Sorry for the lousy use of the quote fxn.

LOL! Very neat, Mike. I was wondering if you'd go there...

"Could the same be said for God?" ha!

Color is one characteristic of an entity, I believe. White light on it absorbs certain wavelengths, and reflects others.

Therefore, color exists independently of the viewer. The (green) tree does indeed make a sound when it falls in the forest.

For the concept "color", one has to have a referent in reality - sensory and perceptual. A 'concept' that by-passes these - must be rationalistic. i.e, It's a floating abstraction, with no pertinence to reality, for a blind person.

Ba'al's "device" creates another concept entirely, stemming from the aural cortex - not the visual. (Same for Braille, and touch.) One could probably describe the form of a tree to a blind man; but describe a color? No way.

Could just as well be describing Beethoven's Fifth to a deaf man.

I thought I’d throw that in and see what response I’d get. The boilerplate arguments I get are analogous to those the medical community gave to a physician named Semmelweis who proposed the idea that bacteria might be responsible to hospital infections. Since the microscope hadn’t been invented, the would be “Randians” (medical community) of the day laughed at him saying that these could not exist as they could not be seen (perceived) when, in fact, there was a "new dimension”,i.e., the microscopic, that humans could not objectively demonstrate at the time.

MSK did not reject the idea that there may be realities for which the human has yet to develop a sense. Might God exist in that reality? To categorically say “no possibility" is being as anti-intellectual and dogmatic as some fundamentalist Christians are when it comes to science.

Just sayin'

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The companion to this question is, "Do sighted people all percieve the same thing when regarding color?" As we only know by comparison with agreed upon objects ("That is blue...yes, that is blue.") there is no way of telling if sighted people all perceive the same thing.

For all I know, my blue is your green -- or something else I've never even imagined. But as long as we agree that green beans are green, then no problem -- no matter what each of us is perceiving.

How would we ever devise an experiment to prove that we all percieve the same actual color when regaring an object that we both agreed to call 'blue?'

We could prove that each of us was consistant in our perceptions ("Yup--- the sky is still blue.") But not that each of us perceived the same sensation.

That we perceived a sensation, yes. But how could we ever prove to each other that we each see the same sensation when regarding 'blue?'

And that fact should be of interest to objectivists; it is another nail in the coffin of collectivist thought...

What else would have no consequence in a pluralistic tribe where there wasn't just one answer to the questions "Why am I here/what is the purpose of my life in this existence?"

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The companion to this question is, "Do sighted people all percieve the same thing when regarding color?" As we only know by comparison with agreed upon objects ("That is blue...yes, that is blue.") there is no way of telling if sighted people all perceive the same thing.

For all I know, my blue is your green -- or something else I've never even imagined. But as long as we agree that green beans are green, then no problem -- no matter what each of us is perceiving.

How would we ever devise an experiment to prove that we all percieve the same actual color when regaring an object that we both agreed to call 'blue?'

We could prove that each of us was consistant in our perceptions ("Yup--- the sky is still blue.") But not that each of us perceived the same sensation.

That we perceived a sensation, yes. But how could we ever prove to each other that we each see the same sensation when regarding 'blue?'

And that fact should be of interest to objectivists; it is another nail in the coffin of collectivist thought...

What else would have no consequence in a pluralistic tribe where there wasn't just one answer to the questions "Why am I here/what is the purpose of my life in this existence?"

What “fact” are you speaking of? You listed a bunch of hypotheticals and what ifs.

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I thought I’d throw that in and see what response I’d get. The boilerplate arguments I get are analogous to those the medical community gave to a physician named Semmelweis who proposed the idea that bacteria might be responsible to hospital infections. Since the microscope hadn’t been invented, the would be “Randians” (medical community) of the day laughed at him saying that these could not exist as they could not be seen (perceived) when, in fact, there was a "new dimension”,i.e., the microscopic, that humans could not objectively demonstrate at the time.

Methinks you came just for the boilerplate arguments as you have offered nothing positive of your own so far. In this case, you lack facts.

By Semmelweiss's day, the microcrope was 200 years old, and "animicules" were well known. The question was not whether or not "germs" exist, but whether they were the cause of disease or an effect of putrification caused by miasma (or maybe something else still). In the 1840s, John Leonard Riddell was one of several scientists who argued for the germ theory of disease. (See my biographical essay on Riddell here.) It took a generation for the argument to be settled. Louis Pasteur was perhaps the last in a line that included Joseph Lister until the germ theory generally was accepted. As Thomas Kuhn pointed out long ago, often a new paradigm is not accepted until the old believers die off.

Let me ask you, 82ARP, if a rainbow falls in a forest and no one is around to see it, does it make a noise? Many posts back, Ba'al said all that needs to be said on this: we manipulate entities such as electrons that we cannot perceive, because we know that they exist, even if we do not know everything (or very much at all, perhaps) about them.

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Methinks you came just for the boilerplate arguments as you have offered nothing positive of your own so far. In this case, you lack facts.

Let me ask you, 82ARP, if a rainbow falls in a forest and no one is around to see it, does it make a noise? Many posts back, Ba'al said all that needs to be said on this: we manipulate entities such as electrons that we cannot perceive, because we know that they exist, even if we do not know everything (or very much at all, perhaps) about them.

You are correct in saying that I have offered nothing positive of my own. As I noted earlier, I am examining my own epistemology and not seeking to make a positive statement about anything. As fellow OLers posted comments, I remarked on the posts. I'm here to learn, not proselytize.

My simplified use of Semmelweis was for the purpose of portraying what he had to deal with when he approached the medical deities, not a explanation of the research of the time. Sheesh!

RE: electrons. Yes, we currently have the Quantum model of the atom and do manipulate electrons, but the nature of the "model" is one that allows for change as further investigation and discoveries are made. I would say the same goes for open Objectivism.

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Suppose we have a musical pitch encoding for colors from red (low pitch) to violet (high pitch). With a little training a blind person should be able to sort colored objects by their color nearly as well as a person with normal vision.

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Suppose we have a musical pitch encoding for colors from red (low pitch) to violet (high pitch). With a little training a blind person should be able to sort colored objects by their color nearly as well as a person with normal vision.

He's not grasping the concept "Color" - he's hearing arbitrary sounds which he's been told

relate to colors. What does the name "turquoise" mean to him?

A concept cannot exist in his consciousness if he doesn't have first-hand experience with it at a sensory level.

A question for you: do you think a blind man dreams in color? And in shapes and forms?

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Suppose we have a musical pitch encoding for colors from red (low pitch) to violet (high pitch). With a little training a blind person should be able to sort colored objects by their color nearly as well as a person with normal vision.

He's not grasping the concept "Color" - he's hearing arbitrary sounds which he's been told

relate to colors. What does the name "turquoise" mean to him?

A concept cannot exist in his consciousness if he doesn't have first-hand experience with it at a sensory level.

A question for you: do you think a blind man dreams in color? And in shapes and forms?

G sharp or some such. A pitch coding for color can be taught to a blind person and he will sort by colors (i.e. the effect of the frequency of lighit) almost as well as a normal sighted person.

Given the encoding he can learn to apply the same name to color-code (turquoise) as a sighted person to the light-frequency(turquoise). Obviously the experiences are different. The normal sighted person gets the color by his visual processing. The blind person gets the color by his auditory processing, but they match, in their effect, when it comes to applying the experience.

In fact all we have is external correspondence. None of us really knows what the experience of another -is-. We only agree on the name we give to our experiences..

Ba'al Chatzaf

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mike82arp said

I thought I’d throw that in and see what response I’d get. The boilerplate arguments I get are analogous to those the medical community gave to a physician named Semmelweis who proposed the idea that bacteria might be responsible to hospital infections. Since the microscope hadn’t been invented, the would be “Randians” (medical community) of the day laughed at him saying that these could not exist as they could not be seen (perceived) when, in fact, there was a "new dimension”,i.e., the microscopic, that humans could not objectively demonstrate at the time.

MSK did not reject the idea that there may be realities for which the human has yet to develop a sense. Might God exist in that reality? To categorically say “no possibility" is being as anti-intellectual and dogmatic as some fundamentalist Christians are when it comes to science.

Just sayin'

What I have always wondered about positing the existence of a god, is why this existence has to be temporally present or past? If one can just say we humans may not have the sense organs (yet?) to perceive it, what not posit that there is no god currently, but it may spring into existence at sometime in the future? If axioms are mutable or malleable why just postulate the existence of it as currently being? How about god doesn't exist now, but in the future it could begin to exist, and then once existing could extend its existence to the past? What would stop someone from postulating that?

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Mike82ARP wrote: "Huh??? Are the trees really green if no one is there to look at them??? Color is objective and not dependent on consciousness to exist. Your statement reminds me of the question, "if a tree falls in the woods and no is there to hear it, does it make a sound?"

Definitely not. You cannot separate concepts of color, vision or sound from the concept of perception. That would make them stolen concepts. There are no percepts without perceiver. What trees do have is a physical qualities which make perception of green or sound possible. Color is objective epistemic, not metaphysical concept. It pertains to consciousness, not existence.

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Von Frisch did some experiments on the senses of bees and wrote a book about his experiments. He trained bees to land on yellow cards. He placed a bunch of cards, all the same size and shape and material but different in color, on a table. The bees landed on the yellow cards, expecting food. This showed that the bees could differentiate between yellow and other colors.

By a series of experiments, von Frisch worked out the following information about the ability of bees to see color.

Bees cannot distinguish between black and red.

Bees see orange, yellow, and green as one color. Frisch called this bee-yellow.

Bees see blue-green as a distinct and attractive color. Frisch called this bee-blue-green.

Bees see blue and violet as one color. Frisch called this bee-blue.

Bees see an ultraviolet color that is invisible to us. Frisch called this bee-ultraviolet.

Bees see all their colors together as a distinct color, but not an attractive color. Frisch called this bee-white.

Bees see bee-yellow and bee-ultraviolet together as a distinct and attractive color. Frisch called this bee-purple.

After Frisch's death, someone got the brilliant idea to invent a camera with a lens that allowed ultraviolet to go thru and film that makes bee colors. Then they took pictures of thousands of flowers to find out what flowers look like to bees. Every flower had a visual nectar guide. Sometimes the nectar guide is visible to us, for example in the tiger lilly, sometimes not. But it is always visible to bees.

Flowers also have an olfactory nectar guide. Different parts of the flower have a different fragrance.

Flowers that are white to us are not bee-white to bees. They are bee-blue-green to bees, an attractive color to them.

Bees can't see red, but red flowers might be bee-ultraviolet.

Green foliage is dark to bees. Flowers are bright to bees, and form a contrast to the green foliage.

As a rough rule of thumb, with a few exceptions, what smells good to us also smells good to bees. But they dislike the odor of sweat.

You ask, what the h.. does this stuff about bees have to do with the topic of this thread? Damned if I know. Maybe someone else can figure it out.

==========

About birds. Eagles and owls have 4 primary colors. We have 3; red, green, blue. Dogs and cats have 2 primary colors.

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Suppose we have a musical pitch encoding for colors from red (low pitch) to violet (high pitch). With a little training a blind person should be able to sort colored objects by their color nearly as well as a person with normal vision.

He's not grasping the concept "Color" - he's hearing arbitrary sounds which he's been told

relate to colors. What does the name "turquoise" mean to him?

A concept cannot exist in his consciousness if he doesn't have first-hand experience with it at a sensory level.

A question for you: do you think a blind man dreams in color? And in shapes and forms?

You miss on the encoding. Color ( which corresponds to light frequency) can be coded as sound pitch by a device that takes light frequency as input and turns out sound pitch as output. So the blind person now has a translation of light frequency into sound frequency which he can process. My guess is that with that translation he could sort out colored objects the same way as a sighted person.

I never said the blind person was perceiving color. I said he was processing light frequency in an indirect way.

Which is exactly the case with normal humans who can process light frequencies above ultra violet. We do it machines that input light frequency and turn out numbers presented to us in a way that we -can- see.

So even though we are "blind" to light above ultra-violet we can still process it. But not with out eyes.

Ba'al Chatzaf

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Suppose we have a musical pitch encoding for colors from red (low pitch) to violet (high pitch). With a little training a blind person should be able to sort colored objects by their color nearly as well as a person with normal vision.

He's not grasping the concept "Color" - he's hearing arbitrary sounds which he's been told

relate to colors. What does the name "turquoise" mean to him?

A concept cannot exist in his consciousness if he doesn't have first-hand experience with it at a sensory level.

A question for you: do you think a blind man dreams in color? And in shapes and forms?

You miss on the encoding. Color ( which corresponds to light frequency) can be coded as sound pitch by a device that takes light frequency as input and turns out sound pitch as output. So the blind person now has a translation of light frequency into sound frequency which he can process. My guess is that with that translation he could sort out colored objects the same way as a sighted person.

I never said the blind person was perceiving color. I said he was processing light frequency in an indirect way.

Which is exactly the case with normal humans who can process light frequencies above ultra violet. We do it machines that input light frequency and turn out numbers presented to us in a way that we -can- see.

So even though we are "blind" to light above ultra-violet we can still process it. But not with out eyes.

Ba'al Chatzaf

No, still at cross-purposes: While I believe this is a conceptual issue, you treat it as empirical.

It was not a problem solving query - "can color exist for a blind person"-not- how can we help

him register color differences? Aids and tools for the blind aren't new. If you give a white cane

or seeing-eye dog to a blind man, you are not bestowing the concept "space" on him. Only how to navigate obstacles.

You and I can conceive of ultra -violet light ... because we have already conceptualized

visible light, and not before. Actually, 'visible' light is not directly visible, anyway - we see its source, and we

see its effects on objects. That's all. Which is why its easier to conceive 'invisible' wave-lengths.

Transposing vision into sound, as with your device, avoids the problem by creating another concept.

If the question were "can the tune of a cello exist to a deaf man?" would a clever arrangement of

flashing, colored lights, indicating pitch and tone - make the sound exist for him? No, since he hasn't

conceived of sound qua sound.

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Transposing vision into sound, as with your device, avoids the problem by creating another concept.

If the question were "can the tune of a cello exist to a deaf man?" would a clever arrangement of

flashing, colored lights, indicating pitch and tone - make the sound exist for him? No, since he hasn't

conceived of sound qua sound.

Deaf people can sometimes feel sound vibrations with their fingers (which are sensitive). This is a much cruder sense for vibration than the ears but it works to some extent. What is sound? It is the vibration we "feel" with our ears?

Besides it is possible for two different concepts to be logically equivalent. Example. Equi-angular triangles are equi-lateral triangles. Angles are not sides and angle measurement is not length measurement but in Euclidean spaces they are equivalent.

Ba'al Chatzaf

Ba'al Chatzf

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People who lack ESP claim that it does not exist.