What color is blue

[paul'smars]

ok. I have never gotton anyone to understand me on this. Am I just weird?

We both agree that this object is blue, but how do I know that what u see as blue looks like what I see as blue. Indeed, what u see could actually be what I see when I look at something green. We just both call it by the same name, since we were tought that since birth. Understand??

[Meeko]

How do we know we where both tought the same name to one particular color? Well I think that people who are Color Blind could comment on this, since I am not....

Out side of Colorblindness, I would think the low number (if any) of color confusion questions proves we were all taught the same way.

Also, what about different languages... I don't think the "word" matters, just as long as the end product is the same.

Artits tend to be more stubborn on calling a hue or shade a more non-standard color... I have arguments with my mom (an artist) about Yellows, Mustards, Oranges etc.

[kunilou]

If I understand you correctly, you're asking if what you call "blue" might instead be turquoise, aqaumarine, cerrulean, cobalt, robin's egg or any of a thousand other shades that fall in roughly the same area of the color spectrum.

The answer is, one person's robin's egg is another's pastel. "Blue" can refer to a whole range of shades, rather than one specific point on the spectrum.

If you're color blind, then of course you don't see blue the way I see blue. "Blue" could mean a particular shade of gray that you associate with the sky, or a sapphire, or something else that other people call blue.

[PRNYouth]

This has nothing to do with shades and hues of the same color, I'm sure.

I'm with you, paul'smars. There is a certain wavelength of light that my brain interprets as blue. Within my mind, that color appears blue. However the PERCEPTION of that color may be the same PERCEPTION you have of a different wavelength of light -- perhaps the one that MY mind perceives as red.

I don't think the two previous posters understood what you're saying (although kunilou got close there in that last bit about color-blindness) ... but I understand, I think. Change "particular shade of gray" to "particular shade of pink" and you're getting close to understanding what paul'smars is talking about.

So if the question is, how do we know that what I see is the same as what you see? My answer is that we can't know that. EVERYTHING in life is filtered through our own perception. Even if we were able to tap into someone else's brain, the resulting information would STILL have to be filtered through our own perception in our own brains.

No matter how hard you try, you can't see through someone else's eyes. That's what this issue boils down to, I think.

[micco]

I think you're absolutely right. There have been a number of threads on this topic, but I don't have any links handy. I'm no expert on brain function, but let me take a crack at it, if only to stimulate the real experts into correcting me.

When you see something blue, it stimulates a certain pattern of brain activity and you have been taught that that stimulation is called "blue". My brain may fire off a completely different pattern of activity when I see blue, but I've been taught to label my pattern the same way you label yours. We know that this activity takes place in the same general region of the brain in everyone because different regions serve different functions, but I don't think there's any reason to believe that the details of the stimulus processing are the same in everyone. In fact, since brains are grown inside us rather than springing forth fully formed according to some universal pattern, it's reasonable to expect every brain to be unique in this respect.

The actual neurological activity in your brain which you label as "blue" is almost certainly completely different than mine. If we had some way to stimulate my "blue" pattern in your brain, you would have no way to interpret it, but I don't think even the concept of that exchange of stimulation makes sense since your brain is completely different from mine (at the neurological level) and there is no neuron-to-neuron mapping between our brains that would allow a low-level duplication of brain activity. If I want to impose a blue signal on your brain, I either need to know what your brain activity looks like when it responds to blue, or I need to input the signal further upstream, maybe in the optic nerve where the signals we interpret as blue might be more universal.

[Amp]

0000FF

[bordelond]

Kunilou, it seems to me that paul'smars' is more complicated than that.

Paul'smars', I think you're getting at something like the following:

Scientist X is studying two subjects: A & B.

Person A's brain interprets the visual information yielded from a given prism in approximately the following chromatic order (as defined by X): red, orange, yellow, green, blue, purple

Person B's brain interprets the same visual information from the same given prism in approximately the following chromatic order (as defined by X): green, blue, purple, red, orange, yellow

So if Person A could somehow borrow Person B's brain, Person A would see purple bananas, green stop signs, a pale-orange-colored sky, buttery-yellow lavender flowers, etc. Yet Person B, living with a "distorted" sense of color, is none the wiser.

.......

Now then, I must bowdlerize a bit:

One simple, initial test that could be used to flesh these perceptions out would be for Scientist X to ask both A & B about the relative darkness or lightness of the colors of certain objects (probably color swatches or chips similar to those used in printing or fashion). For example, yellow objects would appear darker to B than blue objects (given equal amounts of saturation and brightness).

[SentientMeat]

When asked to pick out which wavelengths were "blue", we would presumbaly all go along with this chart (http://eosweb.larc.nasa.gov/EDDOCS/Wavelengths_for_Colors.html), placing "blue" at around 475nm.

You are presumably asking whether someone else might experience this wavelength differently, so that it showed up in their "vision" as what you experience as "red".

Since the electromagnetic radiation of this wavelength is incident on similar receptors in the retina, there seems no reason to suppose this. However, one can never know this to be the case.

[SentientMeat]

Sorry, what you experience as "green".

[scr4]

If I understand the question correctly, it's the same as asking: "When I poke people in their right arms, do they all feel the same sensation? What you feel as pain in the right arm may be what I call a pain in the right thigh." In that case, I think the answer is that the exact electro-chemical response to the same stimulus is slightly different for everyone, but their brains interpret them appropriately. So if I transplant my brain onto your body, it may take some time for the brain to learn what signal corresponds to "pain in right arm".

There is a famous experiment where test subjects wear eyeglasses with prisms that invert the image. They are of course terribly disoriented at first, but after some time (few days?) they get used to it. When they finally remove the glasses, they become disoriented again for a while. This seems to indicate that the brain needs to - and can - learn and re-learn which signal means "light in the upward direction." I don't know if anyone has done an experiment which replaces green light with red (for example), but that might be interesting...

[bordelond]

Originally posted by SentientMeat
Since the electromagnetic radiation of this wavelength is incident on similar receptors in the retina, there seems no reason to suppose this. However, one can never know this to be the case.

It seems to be that comparing preceptions of the relative lightness and darkness of colors might be a first step in determining that people pretty much perceive the chromatic spectrum the same way.

For instance, if Persons A & B from my first post were each asked to draw a grayscale representation of the prism's refraction, Person A would draw something like:

50% gray | 20% gray | 5% gray | 20% gray | 50% gray | 70% gray


Person B would draw it like so:

20% gray | 50% gray | 70% gray | 50% gray | 20% gray | 5% gray


So the difference in color preception would make itself self-evident.

[gluteus maximus]

Originally posted by paul'smars


We both agree that this object is blue, but how do I know that what u see as blue looks like what I see as blue. Indeed, what u see could actually be what I see when I look at something green. We just both call it by the same name, since we were tought that since birth. Understand??

If you mean that, given a particular color sample, your visual experience may be different than my visual experience, but somehow we have a matching descriptive name for two different wavelengths...

How about this test:

Prepare two sets of color samples... say about a dozen different hues in the "blue" range. The color samples are numbered on the back. You and I then see if we can agree enough to match-up our samples (under the same light source) based on what we see, rather than by naming the colors.

If our numbers match, then we know our perceptions of the colors match, and we can procede to agree on names.

Howzat?

Meanwhile...

Sky Blue

Royal Blue

Blue

Dark Blue

Green

Indigo

;)

[II Gyan II]

Philosophically, the question is unanswerable as it deals with the qualia of colour.

However, and I don't have a cite right now, some study showed that humans differ by most 2 parts in 255 in perceiving a color on a computer selected using a standard true colour palette.

[randwill]

I think we all percieve colors pretty much the same. It's why, most of the time, if you ask a kid his favorite color, he/she will say Red.

[Intaglio]

Cyan is Blue in Printing.

[CheekyMonkey613]

Paul .... I've thought the EXACT same thing myself

Furthermore, if we DO all see different colours as the same colour, then maybe our FAVOURITE colour is always the same colour! LOL

... also thinking ... this could explain why people have such BAD taste sometimes in colour combos. ;)

[SubliminaLiar]

I'm with you on this, paul'smars... I used to ponder the very same question as a child in school, looking at crayons.

'Would a rose, by any other name'... well, ya know the rest.

Yellow

Green

Blue

Orange

Black

Oh well; as long as we all agree to STOP for red lights (or whatever color we associate with 'red') then we're all on the same... wavelength, so to speak. :p

[paul'smars]

PRNYouth
Exactly !

micco
Your last sentence lost me.

Amp
huh ?? It that hexi-decimal?

bordelond
Yea, except that I am not sure about your last paragraph.

gluteus maximus
Would your test prove anything??

CheekyMonkey613
hmmmm, that's why I can never match my clothes(not joking)

SubliminaLiar
Thanks, its nice to know that I am not the only one.

[micco]

Originally posted by paul'smars
micco
Your last sentence lost me. Maybe I was getting too far afield. The point was that if you wanted some sci-fi helmet that inserted sensations directly in your brain, it would have to be customized to the individual so it would know what specific brain activity to stimulate for any given simulated perception. AFAIK, there is no universal "blue" brain activity pattern you could insert. On the other hand, if you're inserting data farther out in the neurological chain, say in the optic nerve instead of the brain, it might be possible to define stimulation patterns that were the same for all individuals.

[David Simmons]

Originally posted by paul'smars
ok. I have never gotton anyone to understand me on this. Am I just weird?

We both agree that this object is blue, but how do I know that what u see as blue looks like what I see as blue. Indeed, what u see could actually be what I see when I look at something green. We just both call it by the same name, since we were tought that since birth. Understand??

We don't know and we don't have to either. As long as we both call it blue it doesn't matter what we individually and privately see inside our heads.

Consider the rainbow. If an artist and I are standing side by side looking at one and he or she paints a picture, if we both have normal color vision, I will say that what I see in his painting has the same colors as the thing I see in the sky.

[Alex_Dubinsky]

Well, obviously, you can never know for sure, but CheekyMonkey613 has the right idea. We tend to agree what colors look good together or which ones contrast sharply or which ones don't. I think this hints to the fact that we perceive colors approximately similarly. However, i'm sure the exact hues that people perceive vary quite a bit. The real question is, would it matter? I do not think it would matter at all. For example, try messing around with the controls on your monitor. At first things may look weird, but after a while you'll get used to it and it's not going to matter at all. Conversely, switching back to the more optimal settings will seem like a wonderful change at first, but after a while it, again, isn't going to make any difference. The reason for this is that neurons (on a small and large scale) get used to old stimuli and everything ends up being same old, same old. Don't think you're missing out on anything if someone else's colors are more vibrant. They're taking it for granted and don't even appreciate it, those pigs.

[Mangetout]

It may be that we perceive everything differently from each other; the internalised representation of seeing blue to you might actually be similar to my internalised representation of smelling coffee - it doesn't matter that my representation would be nonsense in your context, as long as it is consistent in mine.

All we can say is that on receiving information from our nerves, your brains do something with the information and that this something is sufficiently consistent throughout the life of an individual that we can come to rely on it as regards interaction with the outside world - there's no way to know if the experience of seeing for me is in any way similar to your experience of seeing, because we can only describe it in terms of the things we see, which are commonly available.

So I see a flashing smooth blue square, but the experience that occurs in your brain might be [what I would describe as] a rough sphere that is clanging and smells of parsnips - but that is normal to you and so whenever you experience what I would describe as a rough clanging parsnip sphere, you describe it as a flashing smooth blue square because that's how flashing smooth blue squares have always inflicted themselves upon your perception.

There's no way to know.

[Cliffy]

I took a class on this very question back in college. The consensus agreed with Mangetout -- we can't know, and it's hard to see why it would matter.

I do disagree with SentientMeat, who suggests this is unlikely. Even if the capture of photons by our retinas are identical, that's very, very early in the process of perception. Our minds do most of the work in translating photons into understanding, and it seems perfectly possible that different people's minds work in different ways on this project.

--Cliffy

[bordelond]

Originally posted by Cliffy
I do disagree with SentientMeat, who suggests this is unlikely. Even if the capture of photons by our retinas are identical, that's very, very early in the process of perception. Our minds do most of the work in translating photons into understanding, and it seems perfectly possible that different people's minds work in different ways on this project.

But consider David Simmon's example of two artists drawing a rainbow - except consider that both artists are drawing the rainbow in grayscale with only a charcoal pencil. If they perceive color differently, their perceptions of the order of colors in a rainbow would be different.

I think it's not possible to truly know exactly how others perceive color. However, I do think it's possible to determine whether or not such differences exist. Consider the hypothetical subjects A & B I posited above, who observe color differently. Both subjects, however, still see the chromatic spectrum as a gradual grade of six or so basic colors. I feel safe assuming that no one would perceive the chromatic spectrum with the colors out of "wavelength" order -- IOW, no one sees a prism's light refraction as green-red-yellow-blue-orange-purple.

Now, it is theoretically possible for people to perceive profoundly shifted chromatic spectrums (as opposed to jumbled spectrums), as my Person B above. However, it seems to me that if people existed who saw such shifted chromatic spectrums, their presence could have been verified experimentally.

[Mangetout]

Originally posted by bordelond
I think it's not possible to truly know exactly how others perceive color. However, I do think it's possible to determine whether or not such differences exist. Consider the hypothetical subjects A & B I posited above, who observe color differently. Both subjects, however, still see the chromatic spectrum as a gradual grade of six or so basic colors. I feel safe assuming that no one would perceive the chromatic spectrum with the colors out of "wavelength" order -- IOW, no one sees a prism's light refraction as green-red-yellow-blue-orange-purple.I don't think it is even possible to determine that the experience we call 'seeing' is the same for everyone - as long as it is consistent and coherent enough per individual that the individual is able to rely upon it to build a useful internalised representation of the outside world, it doesn't matter; the translation of colour into perception is used in not only seeing the rainbow, but representing it on paper as well - we have determined that the individual's perceptiion of ROYGBIV in the sky is similar to the same individual's perception of ROYGBIV on paper - even the greyscale test might be prone to similar failings.

[bordelond]

Originally posted by Mangetout
... the translation of colour into perception is used in not only seeing the rainbow, but representing it on paper as well - we have determined that the individual's perceptiion of ROYGBIV in the sky is similar to the same individual's perception of ROYGBIV on paper - even the greyscale test might be prone to similar failings.

It seems for me that for someone who perceives, say, "yellow" as darker than "purple" would draw a grayscale representation of a rainbow with the most heavily-shaded areas in the center of the bow. I can't conceive -- yet -- of a way around that.

See, this is where I'm going: light-versus-dark seems to be perceived in a universal manner by all humans. IOW, I'm not aware of any humans that can see in the absence of light, or cannot see light reflecting off of objects (aside from cases of blindness).

So, given light-dark perception as one universal -- and human perception of some kind of gradated chromatic spectrum as another -- I think one can extrapolate a lot of information about the way different people perceive color as well. ISTM that a profound difference in color perception could not occur without a profound difference in light-dark perception.

[ekow2kn3]

a rose is still a rose by any other name...
it doesnt matter as long as we come to the consensus that this object is "blue"

[Cliffy]

borderlond, you're tied too strongly to color theory. Why can't greyscale be flopped along with spectrum perception? When your eyes are gathering a ton of photons, you perceive it as a brightness, and no photons are perceived as blackness. But someone might just have a perceptive system where the absence of photons is "displayed" as an undifferentiated whiteness, with additional photons dimming portions of his vision so that he can make out objects by sight as effectively as you can. If so, his experience would be that a blank piece of paper looks "black" (that's what you call it -- he calls it white) and, the longer he rubs his pencil on it, it gets closer to "white" (again, what you call white -- he calls it black).

Further, you're basing the assumption that yellow is darker than purple on your own color experience. There are hues of yellow that are darker than some hues of purple -- maybe someone who does agree with you on value would nonetheless perceive a purple object as the color you think of as dark yellow.

Finally, why do they have to perceive "color" at all -- maybe they see color as a differentially-loud buzzing. Or a sensation of heat that gets greater the more photons an object reflects.

--Cliffy

[Avumede]

Perhaps the fact that we all agree that certain color combinations are more or less pleasing is an indication we all view colors the same way.

[ekow2kn3]

Synesthesia

http://dictionary.reference.com/search?q=synesthesia

[bordelond]

Originally posted by Cliffy
borderlond, you're tied too strongly to color theory. Why can't greyscale be flopped along with spectrum perception?

Well ... my initial answer is: then the person would be able to see perfectly in pitch-blackness, but be blinded by day. But see below.

Originally posted by Cliffy
When your eyes are gathering a ton of photons, you perceive it as a brightness, and no photons are perceived as blackness. But someone might just have a perceptive system where the absence of photons is "displayed" as an undifferentiated whiteness, with additional photons dimming portions of his vision so that he can make out objects by sight as effectively as you can. If so, his experience would be that a blank piece of paper looks "black" (that's what you call it -- he calls it white) and, the longer he rubs his pencil on it, it gets closer to "white" (again, what you call white -- he calls it black).

So this person essentially sees a negative of the world around him. If you shined a floodlight in his face, he's see a blinding flash of ... black. OK, that is also theoretically possible, I imagine.

Originally posted by Cliffy
Further, you're basing the assumption that yellow is darker than purple on your own color experience. There are hues of yellow that are darker than some hues of purple -- maybe someone who does agree with you on value would nonetheless perceive a purple object as the color you think of as dark yellow.

This is why, in such an experiment, it's better to stick only with the basic colors of scattered sunlight -- to avoid issues of "dark yellow" and "pale purple".

Originally posted by Cliffy
Finally, why do they have to perceive "color" at all -- maybe they see color as a differentially-loud buzzing. Or a sensation of heat that gets greater the more photons an object reflects.

I don't think these instances are possible. If they are, the people possessing these perceptive traits are going to be far, far from normal. If a person heard color, then some portion of stimuli that person should be receiving as visual is received as auditory. As far as I can reason, your hypothetical "color-hearer" would be blind. Probably functionally deaf, as well, as the sounds of all the colors in the world around him would interfere with proper auditory stimuli.

[KP]

I think most of us are speaking on the wrong level of abstraction.

The "sensation" or perception is irrelevant. It's at best an association. What we really have is neurons firing in recognizable patterns in time and space. Though many organizational and functional similarities are shared between brains, at the level of conscious thought each person (even twins) is almost certainly wired differently by random forces during the development process, both before and after birth. To use a metaphor, I may use ASCII, but no one else will use the exact same coding; other will use EBCDIC, or some Unicode variant or...

In short: it would be a miraculous coincidence if any two people ever had exactly same spatio-temporal neural response to 'blue'. But that doesn't matter, because that's the way it's always been, and our communications are designed to create a rough consensus that maps our internal neural state (in response to a fixed external stimulus) to the coresponding, but different, neural state in another.

[Mangetout]

Originally posted by bordelond
See, this is where I'm going: light-versus-dark seems to be perceived in a universal manner by all humans. IOW, I'm not aware of any humans that can see in the absence of light, or cannot see light reflecting off of objects (aside from cases of blindness).Yes, but what does it really mean to 'see'? that's the point - the actual process of perceiving an image might be different from brain to brain - If you were able to borrow my perceptual system, maybe what I call 'seeing', you would experience as a bewildering array of smells or sounds, or something simply indescribable. That red things look red and bright things look bright is to be expected.

The greyscale thing is a little more challenging, but again, that people represent some colours as darker shades of grey than others might just be down to the fact that light things look light and dark things look dark - the relationship between pink and red in your brain might be perceived in my brain as what you would call the relationship between the flavours of butterscotch and caramel - as long as there is a consistent framework of association and relatedness, complement and clash, the internal perceptions could be wildly different and nobody would ever know.

[Cliffy]

Originally posted by bordelond
As far as I can reason, your hypothetical "color-hearer" would be blind. Probably functionally deaf, as well, as the sounds of all the colors in the world around him would interfere with proper auditory stimuli.

I agree that this is probably wildly unlikely, but you assume that because you don't hear as good as you see, that sight couldn't be effectively perceived audibly. But I see no reason to assume that's true -- remember, we're talking about something going on after the photons have entered your eyes. It's just that the dude who hears color would have a different display mechanism. I think Mangetout addresses your objection nicely.

--Cliffy

[GuanoLad]

You realise, of course, that this particular philosophical (?) question will appear in a movie script one day, and the few people who have never thought about it (and I bet it's not a lot of people at all who haven't) will brand the movie some kind of amazing new insight for the world at large.

cf. The Matrix

[Mangetout]

It has appeared in a movie in the guise of 'how would you describe colour to a blind person? - which is pretty much the same philosophical issue.

[bordelond]

Originally posted by Mangetout
It has appeared in a movie in the guise of 'how would you describe colour to a blind person? - which is pretty much the same philosophical issue.

That was in the movie Mask. Eric Stoltz's character Rocky meets a blind girl, and demonstrates some colors to her using various objects. I forget the details.

[bordelond]

Originally posted by Mangetout
Yes, but what does it really mean to 'see'? that's the point - the actual process of perceiving an image might be different from brain to brain - If you were able to borrow my perceptual system, maybe what I call 'seeing', you would experience as a bewildering array of smells or sounds, or something simply indescribable. That red things look red and bright things look bright is to be expected.

The greyscale thing is a little more challenging, but again, that people represent some colours as darker shades of grey than others might just be down to the fact that light things look light and dark things look dark - the relationship between pink and red in your brain might be perceived in my brain as what you would call the relationship between the flavours of butterscotch and caramel - as long as there is a consistent framework of association and relatedness, complement and clash, the internal perceptions could be wildly different and nobody would ever know.

I see now -- you're approaching this completely differently, and
we've been talking past each other somewhat. I largely agree with your post quoted here. I'm not really interested in this angle, though.

[bordelond]

Originally posted by Cliffy
I agree that this is probably wildly unlikely, but you assume that because you don't hear as good as you see, that sight couldn't be effectively perceived audibly.
... hmmm. We may be talking past each other here. IMO, if visual stimuli could be perceived audibly, it's no longer sight. It's hearing -- or perhaps a form of "sonar".


Originally posted by Cliffy
But I see no reason to assume that's true -- remember, we're talking about something going on after the photons have entered your eyes. It's just that the dude who hears color would have a different display mechanism.
... if someone can only hear color, then they certainly aren't seeing color -- regardless of where photons are landing. This person's eyes have become another set of "ears". You may have lost me here.

[paul'smars]

micco
That's what I thought u said, but would not that be the same regardless of where the input is. In the end, it all ends up in the brain.

David Simmons
Aggreed, but I never suggested there was any real point to this. Most of the things that I ponder have no real meaning in the end, but they are still FUN.

Originally posted by Alex_Dubinsky
"Well, obviously, you can never know for sure, but CheekyMonkey613 has the right idea. We tend to agree what colors look good together or which ones contrast sharply or which ones don't. I think this hints to the fact that we perceive colors approximately similarly. "

I disagree. Matching colors is just what we are tought, right? So, if I was tought that Red and Blue look good together, well, it would not matter what my mind preceived those colors to be.

Mangetout
yup.

Cliffy
cool

Originally posted by bordelond
I don't think these instances are possible. If they are, the people possessing these perceptive traits are going to be far, far from normal. If a person heard color, then some portion of stimuli that person should be receiving as visual is received as auditory. As far as I can reason, your hypothetical "color-hearer" would be blind. Probably functionally deaf, as well, as the sounds of all the colors in the world around him would interfere with proper auditory stimuli.

What's "Normal"? Just what your taught, right....


Originally posted by Mangetout
...the internal perceptions could be wildly different and nobody would ever know.

Exactly. This is great.

[II Gyan II]

Originally posted by bordelond
... hmmm. We may be talking past each other here. IMO, if visual stimuli could be perceived audibly, it's no longer sight. It's hearing -- or perhaps a form of "sonar".



... if someone can only hear color, then they certainly aren't seeing color -- regardless of where photons are landing. This person's eyes have become another set of "ears". You may have lost me here.

The problem as I see it here is that you're tying up your debate too closely with your personal perceptual experience. When someone hears vision and sees sound, they don't know that they're "hearing" color and "seeing" sound because that is how they've always experienced it. Those modes of perception become defined in their awareness as the normal modes of perception. And that as long as one's perceptual apparatus is consistent troughout life with regards to motor memory, there is no problem. If it doesn't affect motor skills, then it's not a problem if it changes, as long as all memory of such perceptions change uniformly as well (If my blue changed to red one day, the red sky won't look different to me if all my memories of the sky get substituted with the new perception as well).

[boofy_bloke]

I can experience light in a way that is not visual.

When I am suffering from a breakthrough episode of Chronic Neuropathic Pain (imagine a 10/10 headache) intense light makes my head "buzz-tingle-fzzzt". It isn't like the pain that you get when walking out of a dark room into the bright sunlight. It is a form of synaesthesia (see above). CNP is itself a form of synaesthesia.

This does not mean that I can't feel someone's hand on my head, so I don't think that a color-hearer would be blind or deaf, they would get added value from the things at which they look... the way that flowers glow when a bee looks at it because bees see UV light.

[bordelond]

Originally posted by Gyan9
The problem as I see it here is that you're tying up your debate too closely with your personal perceptual experience.

... well, I am a human being. I doubt that my perceptual experience is atypical. You may posit that I'd never know if it was. I'd posit back that if I'd never know, it doesn't matter. See below:

Originally posted by Gyan9
When someone hears vision and sees sound, they don't know that they're "hearing" color and "seeing" sound because that is how they've always experienced it. Those modes of perception become defined in their awareness as the normal modes of perception.

OK ... but if someone thinks they are "seeing" but they are really "hearing", that's tantamount to actually seeing AFAIC. I'm trying to stick with testable, verifiable phenomena. What goes on neurologically in someone's brain is not of particular concern to me.

I don't think things get all that convoluted. Just MHO. Can't prove it, of course.

[II Gyan II]

Originally posted by bordelond

What goes on neurologically in someone's brain is not of particular concern to me.


Then I'm surprised that you participated in this thread.

[bordelond]

Originally posted by boofy_bloke
I can experience light in a way that is not visual.

When I am suffering from a breakthrough episode of Chronic Neuropathic Pain (imagine a 10/10 headache) intense light makes my head "buzz-tingle-fzzzt". It isn't like the pain that you get when walking out of a dark room into the bright sunlight. It is a form of synaesthesia (see above). CNP is itself a form of synaesthesia.

If I am following you correctly, you're synaesthetic reaction to bright light (while in a CNP episode) is based on your ability to see an unusually bright light. Some questions:

1) You're in a CNP episode, laying silently in a pitch-dark room. A firefly flies in and lights up. You see the firefly. Does the firefly cause pain?

2) You're in a CNP episode, laying silently in a pitch-dark room with completely opaque walls. Someone in an adjacent room turns on a lamp. Can you feel the lamp's light?

3) You have an opaque blindfold over your eyes, and an opaque hood over your head. Someone shines a floodlight in your face. Do you feel pain?

[bordelond]

Originally posted by Gyan9
Then I'm surprised that you participated in this thread.

No ... think about it. What goes on in someone's brain can be speculated on ad absurdium (sp?). No one can test that, as far as I know.

But the ways in which people perceive color visually can be tested by looking at how one person (the subject) communicates color to another (the scientist). If the scientist is testing for the right things (far beyond simple color naming), variations of individual color perception can be rooted out, IMHO.

[II Gyan II]

Originally posted by bordelond

But the ways in which people perceive color visually can be tested by looking at how one person (the subject) communicates color to another (the scientist). If the scientist is testing for the right things (far beyond simple color naming), variations of individual color perception can be rooted out, IMHO.

How? What would these tests be?

[t-keela]

Does this thread actually belong in GQ?

My perception is NOT. ;)

Color identification is learned. Blue is one of the three primary colors (red, yellow, blue) People universally recognize and identify these colors without confusion. When these primary colors are mixed (secondary=green, orange, purple) confusion starts.

"Is it blue or green", "red vs. orange"...etc.

Do we see them differently? Sure we do. Color recognition involves our experience with similar colors. A person having never seen complex colors (ie: aquamarine, coral, lavender etc.) might be confused when asked to identify these examples.

(I'm gonna post now....my PC is trippin')

[wolf_meister]

Well, some very scholarly, erudite answers there. I'm going to put myself out on a limb and say the answer to the original posting is .............................. it's blue !!!
Thank you.

[paul'smars]

Originally posted by Gyan9
How? What would these tests be?

Ditto

wolf_meister
Finally, a clear consice answer that I understand. Thank you.

[paul'smars]

BTW, I feel complete now. This is my first post that has received such a large following. I have arrived. <G>

[wolf_meister]

LOL paul'smars
Yes I'm an honors PhD Graduate from the School of Stating the Blatantly Obvious.
Seriously, I think it is a sign of SDMB recognition when you start a message thread that gets a huge response. (Hey .... 2 pages !!!)

[boofy_bloke]

Originally posted by bordelond
If I am following you correctly, you're synaesthetic reaction to bright light (while in a CNP episode) is based on your ability to see an unusually bright light. Some questions:

1) You're in a CNP episode, laying silently in a pitch-dark room. A firefly flies in and lights up. You see the firefly. Does the firefly cause pain?

2) You're in a CNP episode, laying silently in a pitch-dark room with completely opaque walls. Someone in an adjacent room turns on a lamp. Can you feel the lamp's light?

3) You have an opaque blindfold over your eyes, and an opaque hood over your head. Someone shines a floodlight in your face. Do you feel pain?

1. We don't have fireflies in Sydney but I don't think it would. It's the intensity of the light more than the contrast with the surroundings.

2. I only experience the light as touch if I see it.

3. I can't put things on my head because it induces pain - I couldn't perform this experiment.

[Topologist]

Originally posted by paul'smars
ok. I have never gotton anyone to understand me on this. Am I just weird?

We both agree that this object is blue, but how do I know that what u see as blue looks like what I see as blue. Indeed, what u see could actually be what I see when I look at something green. We just both call it by the same name, since we were tought that since birth. Understand??

If you're weird then so are a lot of philosophers. (Well, OK, that's not unlikely.) I first ran across this sort of discussion when I took a philosophy of mind course with Ned Block (http://www.nyu.edu/gsas/dept/philo/faculty/block/) a little over 20 years ago. This is the problem of qualia (http://plato.stanford.edu/entries/qualia/) (that link may or may not be the best or most understandable, but I happened to run across it), roughly the qualities that define "what-it's-like" to have an experience. How do we compare your experience and my experience of seeing what we both call blue? Do they have to be at all the same? Does a difference matter in any way? If not, is it really a difference? Etc. Any theory of the mind has to explain qualia somehow; qualia are also used sometimes to argue against the possibility of true artificial intelligence. I was bold enough to disagree with Block back then about qualia in papers I wrote for his course, but I haven't followed the arguments or even thought about it much in 20 years. He's the philosopher; I'm just a mathematician.

[ekow2kn3]

The background of this post is blue, the border of the post is blue, my scroll bar is blue, the profile search and buddy buttons are blue, the banner that says Straight Dope is blue with yellow writing, here is your blue!

[ekow2kn3]

although, someone's monitor might have different colors represented, making these not actually blue, and what happens when you put on sepia sunglasses? is the ball still blue? what i'm asking now is: Is the object actually blue, or is what we perceive blue, because if i put on different colors of shades, objects change color, and while it is still a ball, it is no longer blue to me, although to my friend without sunglasses, the ball is still blue

[aerodave]

In response to Topologist's post, I can't see for myself how the questinable nature of qualia prohibits the creation of artificial intelligence.

Just as if it were another person, how does it matter how the machine experiences the color blue? We have machines that can recognize color, and, as far as I can tell, that's all that matters. If I have a machine to which I can show a color, and say "what color is this?" and get a correct answer, then it has met any requirements I could think of. That's all you can expect from a real intelligence.

Substitute any sensation for color in the above example, and the point is the same.

[eburacum45]

Synaesthesia certainly seems to give a vague clue about the realities of different people's qualia; it seems that there is little correlation between the sensations felt by people when experiencing this crosscircuiting of the senses;
one person associates blue with the feel of sandpaper, another with the smell of roses;
this tends to suggest that we are all wired up differently inside.

Set this against the hundreds of common qualities shared by humans and human behaviour the world over; there is evidently a long list of behaviours preprogrammed into humans which pre-empt enculturation.

In short we have a very similar internal architecture, and the encryption of our qualia does not (in my opinion) run very deep.
__________________
SF worldbuilding at
http://www.orionsarm.com/main.html

[t-keela]

BLUE

There ya go...that's blue for ya. :eek: Does everybody agree?