What if every person's perception of color was different?

There would be know way of telling.

supposedly they are, though not like that. People’s receptors for each colour vary in number for each colour sorry I don’t remember all the jargon and details meaning one can have disproportionate views of colours. So an olive green to you could look more yellow to me, which I think also puts a nice wet blanket on artists’ squabbles about exact colours…

@lamedb- How exactly would that put a blanket on artist’s squabbles about exact colors?

This is a classical philosophical misbelief that in my mind has been disproven pretty clearly. This is argument is from Douglas Hofstaders book “I am a strange loop” (excellent book btw).

Say a person has an inverted perceptions of white and black. This makes no sense as the properties of black and white are dependent on how much light is reflected by a surface. If the case was that the persons perceptions were inverted, he would see better when it’s dark outside. No such person has been found to date.

How does this apply to the other colors you ask? Well, different colors have different properties under different lighting conditions. Take red for example, if you’ve been outside on a dark night you may have noticed that red fades to black much faster than other colors, say a person has inverted perception of red and yellow, he would find that yellow fades faster than red. Nobody has been proven to have this property of vision either.

Our perception of color is determined by the biological properties of our rods and cones in our eyes, and the wiring of our brains. So the bottom line is we all experience colors in the same way (although your emotional connotations to for example blue will of course be different from mine), no matter the apparent mystery of trying to explain how one experiences blue.

@AstroChuck I’ve got some friends who think it’s a valid argument to discuss what a particularly vague colour actually is, what it is composed of, and the predominant colour.

For example: There was a sign in a mall and I asked my friend if he thought it was more green or blue. He thought it was predominantly blue; I thought it was definitely green with gray and blue to haze it up. He persisted that it was such-and-such, and it never got anywhere…

Maybe you thought I meant ‘exact’ in the sense of an intense colour? Don’t know how to edit my response to clarify that one…

I’m of the opinion that it is variable just like any other sense. Some people feel cold while others in the same temperature don’t and the same can be said for smell and taste.

Well there is something called colourblind, where you can’t see certain shades of colour, I know I have it.

@pjanaway More support for the claim that color perception is goverened by physiology and not philosophy. :)

It would make visual art a much more difficult proposition.

Edit: ...no way of telling.

I think it already is different. That is, color has an exactly similar “appearance” to everyone: a certain color will reflect a certain (exact) wavelength of light. That doesn’t change.

But people’s perception is… whatever they perceive. Some people are color-blind (which we already know; they either can’t perceive certain colors, or they perceive those colors as “the same as” some other color). And for others, “I don’t like blue; red is my favorite color.”—is their perception.

Sort of on this topic- my sons had a friend in high school who was colorblind. He once referred to “the cat w/green spots”. Of course he was teased for it.

A distinction has to be made between the apparatus of the eye and what the brain then does with that information. The eye, with its wavelength-specific receptors, will respond to the different parts of the light spectrum in ways that are probably quite consistent between individuals (in other words, if we were to swap eyes, that probably wouldn’t change our color perception). This is the reason that we consistently have the same overall structure to our sight, as @nisse points out.

But technically speaking, there’s still no “color” at this stage of the process, just nerve impulses sorted according to the wavelength that produced them. Color occurs in the brain as it uses the input of the senses to construct a conscious representation of the world. It’s here that, for the first time, an actual subjective experience of the qualities of the world are generated. This is true of color as it is for taste, sound, etc. These actual experiences, called “qualia”, are inseparable from consciousness itself; it’s fair to say that these qualia are consciousness.

The way that consciousness (including color perception) arises from the activity of neurons, and which parts of the brain are involved, is not even close to being understood. The qualia we call “color” may not even happen in the primary vision processing centers in the visual cortex, but may only arise as a result of much feedback with several other higher cognitive processing centers. We just don’t know.

So, while it’s a relatively simple matter to know what the eye does with light, that tells us very little about our actual experience of color. We can speculate on the consistency of qualia between individuals, but there really is no way of knowing.

I don’t think there’s any way to tell as it’s all subjective in it’s relationship to the viewer. I do know that my right eye sees more red and my left eye sees more green. I wonder if the fact that those colors are complements has any significance?

While @Harp makes a strong argument, i feel there is still something wrong with the whole swapping of colors idea, so i revisited my copy of the book “I am a strange loop” to bring up a few more points. I’ve tried to recreate the argument as shortly as possible. I do not claim to make full justice to the original. If you are interested in this question i warmly suggest you pick up a copy of the book that brings up this and many other interesting questions.

The riddle stems from the idea that you are so different from me that there is no way to cross the gap between our interiorities – no way for you to know what i am like inside and vice versa. The riddle is based on the idea of an unbridgeable You-Me chasm. The idea is a close cousin to Cartesian Egos, or the notion that consciousness is something “outside” of the physical universe.

Let’s explore another idea for a while. What if all the chirpy high notes on the piano sounded very low to me, and all the the deep low notes sounded very high. This to me sounds very implausible, after all, very low notes generate shakings that we can feel very clearly. This establishes a simple and obvious difference between the high end and low end of the audible spectrum. Well, all right. If the idea of a swapped sonic spectrum is incoherent, why should the visual swapped spectrum seem any more plausible? The two ends of the electromagnetic spectrum are just as physically different as the two ends of the audible spectrum.

I hope at this point you agree that the physical swapping of colors is not very plausible.

Unlike rumbles and shakings, the activation of pigments and nerve impulses are only intellectual abstractions to us, and this gives us the idea that they are totally disconnected from physics.

Let’s now discuss the implications of the notion that external stimuli is independent from subjective feelings.

Maybe, just to pick a random example, the abstraction of “liberty” feels to me like what the abstraction of “imprisonment” feels like to you – it’s just that we both use the same word “liberty” for it, and so we are deluded to thinking it’s the same experience. This sounds pretty unlikely, as liberty is pleasant and imprisonment is unpleasant.

Why is is that those who propose the swapped colors idea always do so for experiences that lie on a one dimensional scale? What is so holy about shuffling colors inside a spectrum? Why not shuffle all sorts of experiences arbitrarily? Maybe your internal experience of redness is the same as my experience of a low piano note. Maybe your internal experience of watching a soccer game is the same as my experience of watching basketball. Or the same as my experience of wrapping Christmas presents. I hope that this sounds incoherent to you and that you can move step-by-step backwards to the swapped colors idea.

The swapped spectrum idea is a glorious mix of guts and timidity. While it boldly denies the physical worlds relevance to what we feel inside, it meekly limits itself to a one-dimensional spectrum, and to the electromagnetic one to boot. The sonic spectrum is too tied to physical events like shaking and vibrations for us to give the idea of a swapped sonic spectrum any creedence, and if one tries to carry the idea beyond the one dimensional spectrum, it rapidly decays into absurdity.

@nisse I’ll need to get back to this when I have more time. Thanks for a good discussion.

@nisse I did read I Am a Strange Loop some time ago and enjoyed it. Thanks for refreshing my memory on Hofstadter’s line of reasoning.

Here are a few of the things which I think need to be considered, though I’m not yet clear in my own thoughts on exactly how to put them to work:

First, as I said earlier, whatever color is, it happens in the brain. We know this because it’s possible to generate a perception of color by direct electromagnetic stimulation of the visual cortex, without the need for light entering an eye. What is produced by this means is not an “illusion” of color, but color pure and simple. All color is only this—the activity of neurons. Physics has never found color (or sound or taste, etc.) outside of a brain. There is even a serious argument being made that space and time, too, are creatures of the brain and not properties of an external reality. Even the ideas of “externality” and “interiority” are products of the brain’s generation of consciousness.

It should be possible, then, to directly stimulate a precise set of neurons in one brain’s visual cortex and produce a sensation of a very specific color. Now suppose that you want to produce the identical sensation of color in a different brain; can we assume that brains are so similar that we will be able to find perfectly analogous neurons to stimulate in this new brain? That would seem to defy what we know about the way neural connections are formed on the fly.

We can get a glimpse of the “messiness” of the neural networks in the sensory processing areas by considering synesthesia. Synesthetes experience crossover of qualia between senses, so that seeing a letter or number triggers the qualia of a very specific color (in the most common form of synesthesia), or odors are experienced as color, etc. Non-synesthetes would say without hesitation that olive green is not a property of 3, but for some synesthetes it unambiguously is. Again, the color isn’t a hallucination or illusion; it’s as factual as the color of an apple to anyone else. And there’s very little commonality in the color associations between synesthetes, so some see “B” as one color, others see it as a different color. It’s tempting to dismiss synesthesia as an abnormality, but many think that we might all begin life as synesthetes and only gradually differentiate the senses as we grow.

I think it’s especially noteworthy that by far the most common forms of synesthesia involve color. this particular aspect of sensory consciousness seems particularly prone to variations in “wiring”, so maybe there is some reason to think that vision has different ground rules than other senses.

Another interesting visual phenomenon shows how the brain is actively involved in creating qualia, rather than passively reflecting an external reality. We all have two small blind spots in our visual field caused by the area of the retina where the optic nerve is attached; this part of the retina has no sensors. We literally can’t see anything in these two spots. Yet we’re not aware of them unless we purposely go looking for them. This is because the brain is constantly filling those spots in with qualia. The brain decides what to “photoshop” into those spots based on information in the areas surrounding the spots. It will fill them with yellow if the area around is yellow. It will even reproduce a simple pattern to match the surroundings. But what you’re seeing in those spots isn’t in any external reality. The brain cooked it up.

I say all this not to assert that we’re all seeing different colors. My assertion is simply that there’s no way of actually knowing. Hofstadter’s reasoning is intuitively satisfying, but falls short of proof. The upside is that it makes absolutely no difference. We can assume either position and it doesn’t change a thing

If we are discussing the internal symbol of “redness”. The question we are trying to ask ourselves is “Is my redness similar to your redness?” and where we run in to trouble is in how to define the measure of similarity.

Indeed the only reasonable answer to the previous question is “similar in what way?” and I can’t think of any good yardstick other than comparing it to real world items such as blood or apples.

I think this sidesteps the original question a bit, i think the core of the ídea could be phrased like this: “If i had a machine that allowed me to step into your head and see what you are seeing, would the ocean all of a sudden look red?” and in this sense I think the answer would almost certainly be “No. The psysiology of the eye and the visual pathways are most certainly the same. And most likely the visual cortex and image processing too. Although we certainly do not know for sure, there is absolutely nothing that points to this being the case.”

What the swapped spectrum argument seems to revert to when pressured is instead this question: “If we both see blue, do we have different mental symbols triggered in us?”, and again, this is a much easier but entierly different question. I think almost everyone agrees that the answer here is “Yes, the high level mental symbols triggered by low level sensory inputs is almost certainly different between individuals.”

Regarding the existence of Synesthetes, while it certainly was intriguing (I previously had no idea they existed), i dont see how they relate to the problem at hand. If i understand the symptoms correctly they tend to associate things without color (for example letters or numbers or smells) to specific colors. I don’t really see how this affects the problem – i mean we are not discussing the ability to couple different symbols to eachother – this is a fundemental building block in human intelligence, and everyone does it. Here’s an example: Synesthetes couple the number “8” and the color “blue”, while normal persons couple the symbol “angry” with the color “red”, or the symbol “sad” with the color “blue”, i mean this is how we think and make sense of the world.. You couple concepts or symbols together; “red” and “apple”, “car” and “tires” and “steeringwheel”, it doesnt provide any evidence in either way in my opinion.

I’m sure Hofstader didn’t intend for his argument to be any sort of proof, rather he attacks the problem by showing that it makes no sense if you take it a bit further (and indeed there is nothing suggesting that taking it a bit further changes the original problem in any way), but now all of a sudden we end up with all these less than probable notions (such as watching soccer = watching basketball). While they are alot less probable than the what the initial, alluring phrasing of the the swapped colors problem suggests, they are by no means impossible.

He also attacks the suspicious fact that this riddle has emerged in the one area where we can’t verify it either way, and the reason the riddle doesn’t exist for other similar concepts such as the sonic spectrum is that they can be easily disproven. I agree that this is circular reasoning (it wouldn’t be a riddle if it could be easily disproven) and does not disprove the idea for once and all time, but it certainly it sheds light on the surrounding territory.

Sure, it’s possible that we have swapped the internal representations/symbols/qualias for “red” and “blue”, but it’s just likely as having swapped the internal representations of “watching soccer” and “wrapping Christmas presents”.

In my mind this makes the original idea of swapped colors (which is also very intuitivly satisfying or intriguing) a lot less probable, but certainly as you say, not disproven.

Indeed, good discussion and very good points brought up by you.

I don’t have anywhere to go with this, but just want to address a couple of points

The neurologist V.S. Ramachandran has done a lot of work on the problem of qualia. His work indicates that they arise at a level of processing that precedes the higher cortical levels involved with symbols.

In studying grapheme/color synesthetes (those that see colored letters and numbers), he found that some are “lower” synesthetes and some are “higher” synesthetes. Lower synesthetes will see the grapheme “3” in color, but not other representations of “threeness” such as the roman numeral III or the word “three” or an array of three dots. Their synesthesia is confined to the lower level of processing that perceives the grapheme (located in the fusiform gyrus), before it acquires any semantic content. In other words, it is not yet a symbol. Higher synesthetes also experience color qualia at the symbolic level, so higher in the processing chain.

I’ve come across many synesthetes, most of whom actually didn’t know that their quirky perception had a name. Some were even unaware that we don’t all see this way. There are several here on Fluther.

@nisse Since you brought up the use of metaphor, as in describing anger as red, etc., this is another thing that Ramachandran explores. He speculates that the “normal” person’s ability to create and understand metaphor is a covert expression of the same kind of neural cross-connection that typifies synesthesia. He points out that synesthetes are represented in far greater numbers among artists, poets, and creative writers than among the general population (up to 1 in 28 among visual artists vs. 1 in 2000 in the general population).

A specific area of the brain, the angular gyrus, is implicated in both synesthesia and metaphor. It acts as an interchange for several other brain areas. People with damage to the angular are often extremely literal thinkers who can’t grasp metaphor.

I’m colour-blind. It’s no big deal, really. I know I don’t see the same as other people, mostly grays and dark or light. It doesn’t bother me.

I’ve often wondered about this because I an a pro photographer. My Wife and I would work hard to color correct an image to be printed by our lab only to have it come back wrong. This was in the film days. in the digital era using a calibrated monitor, a pro lab, and color by numbers in Photoshop we really did have WYSIWYG color. But our perception of what was pleasing wasn’t necessarily the same as the clients. In general the general public was not near as picky or knowledgeable on color issues. They were used to $0.09 drugstore prints or worse homemade inkjet prints. The commercial clients on the other hand, especially printers were very picky about color. After 20 years of doing this I see good, bad, and color shifted images everywhere we look.