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The color of color

  1. Jan 10, 2004 #1
    Color, like beauty, is intrinsic. IMO

    The usual reductionist thinking is that color is assigned by our minds according to the frequency of the light sensed. Light does not contain or carry the property or value of color but rather has frequency, wavelength or energy level that we perceive and as the value of color to it. I, myself have long thought this and thought the same about sound. I was wrong. Having thought about this for some time I have come to the conclusion that color, sound and beauty are intrinsic and perceived as those values rather than assigned those values by our minds. Following are the reasons that I have changed my position and it has to do with information more than perception.
    Light, photons are generated, emitted by bodies, in quantum.
    The energy level of the quantum of light is determined by the energy level of the emitting body. This energy leveldetermines the frequency or wavelength of the light, photon, quantum. This wave length is information about the radiating body that we can and do perceive as color. If the light is reflected off of another body, the light then is altered. Its characteristic wavelength and intensity is changed by the reflecting body unless it is a perfect reflector or mirror. This is information about the reflecting body.
    The medium through which the light travels may also change its characteristics and this is information about the medium also.

    With our eyes and instruments we can detect these characteristics and deduce which characteristics are due to which process or body.
    Light (and sound) of different frequencies or wavelenghts or energy levels have different properties of reflection, penetration etc. All of this is a function of its wavelength which is intrinsic to the light. We call these different characteristics color. Color is generated or radiated outside of us and comes to us with this information we call colors as an intrinsic characteristic. We may assign the name of the color and we may all perceive each color differently but it is still a perception of a characteristic of the light entering our eyes.

    Life is an opportunist. It takes advantage of whatever is at hand. It uses it's environment any and every way it can. Vertually every form of life on earth uses and responds to light in some way. Sight is a sense that was developed by life to gather information about its surroundings using light. Life did not invent light nor did it invent color but evolved to use light and its characteristic colors to gather information about its environment.

    Again, we, life, do not invent or assign color but percieve color as an intrinsic characteristic of the light we sense and this color is information contained or carried by that light that is external to us.
    I welcome any and all thoughts, ideas, and/or arguments for or against.
  2. jcsd
  3. Jan 10, 2004 #2
    "Having thought about this for some time I have come to the conclusion that color, sound and beauty are intrinsic and perceived as those values rather than assigned those values by our minds."

    I don't understand your distinction between perceiving a value and the brain assigning a value. After all, even sensory information is processed by the brain.

    I would also disagree with the lumping of beauty in with the likes of color and sound. Color and sound are sensory information; beauty is an intellectual construct like justice or truth.

    "Light (and sound) of different frequencies or wavelenghts or energy levels have different properties of reflection, penetration etc. All of this is a function of its wavelength which is intrinsic to the light. We call these different characteristics color. Color is generated or radiated outside of us and comes to us with this information we call colors as an intrinsic characteristic."

    This seems to be the crux of your argument, and I disagree with the distinction made. You seem to say that the reductionist view is that color is the mind's interpretation of wavelength, a characteristic among others of light. Yet, you say that we call these characteristics color, and that color is a characteristic of light. "We call these characteristics color," indicates that the mind's interpretation is happening, that the mind is interpreting wavelength.
  4. Jan 11, 2004 #3
    The distinction is that color exists as an intrinsic characteristic of light, rather than our simply sensing the various frequencies of light and assigning a color value to that light that we sense. Does color exist or is it only a function of our brains, an assigned perception?
    I am saying that color is intrinsic. It is external to us and is information carried by the light that we sense. The property of light that carries this information is wavelength. we measure it as frequency; but, it is color that we are actually measuring and perceiving.

    I say that our senses and perceptions are passive. We receive via our senses information of our environment and this information is perceived and interpreted in our minds or by our brains as received.
    Our brains do not assign values like color or tone, intensity or loudness. This information is what we are sensing not what we are making up in our own minds.
    Again is color intrinsic, does it exist or is color merely a perception, a subjective property of our mind/brain?

    As far a beauty is concerned, I argued some months ago here that beauty is intrinsic in the thread "VALUE THEORY, AH?" One of the questions concerned color. I was not able to address it at that time.
    This post is partially in response to that question and partially in response to the various and numerous materialist and reductionists vs non-materialist threads. It is also to refute and correct my own posts on this subject including sound i.e. does a tree falling in the woulds make any sound if no one is there to hear it? I said no. Now I say yes, the information is still there whether there is anyone or anything there to hear it or not. The same thinking applies to light, color and beauty. I know others will disagree; but, I think now that I can better support this position after having thought about it for a while.
    Last edited: Jan 11, 2004
  5. Jan 11, 2004 #4


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    I believe the input side of color perception is well understood. The ambient visible radiation is sampled for intensity at three narrow, fixed frequency bands - this is done in the cones of our retinas - and the band-tagged intensity signal passed to the visual cortex at the back of the brain. It is from these band specific intensities (along with other non frequency specific data) that our color experiences are generated, and that happens in the brain. Of course we don't know how the color sensation - or qualia if you prefer - is generated, yet. But research is proceding.
  6. Jan 11, 2004 #5
    Okay, SA, this is understood. The question is why should life in general and humans in specific evolve the means to sense these frequencies if not to gather information that is already present in this case color in the form of frequency of light or if you prefer wavelength? Why does life use color with such enthusiasm and abundance unless color itself is intrinsic and available at least here on earth. Again life did not invent or create color. Our, life's senses are passive, receiving only what is available. Yet life also uses color actively as in bioluminosity and active skin coloration. This, I think, is adoption and opportunism using properties already present and intrinsic, not generating stimuli for subjective color perception. I agree that it amounts to the same thing in the end but is color intrinsic in nature or purely subjective?
  7. Jan 11, 2004 #6


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    Actually, "color" doesn't necessarily have anything to do with the frequency of light at all. That's because the brain never deals directly with the light being percieved. When light strikes the retina, the data is converted into an electric signal and sent to the brain. This signal is then processed in the visual cortex where the final image ends up. As such, you don't need eyes to see colors. Stimulating the brain directly will produce vivid colors, and no outside light is required.

    In that sense, we can see that color is most certainly not an intrinsic property of the light itself.
  8. Jan 12, 2004 #7
    Stimulating the brain to see colors only proves what we already know, the brain is wired to perceive colors whether the stimulation comes from the optic nerve or an electric probe. There is only one reason for this and that is because our eyes have the ability to detect and discern color in the light that they pick up from the outside world.

    Tell how and why our brains are wire to perceive that which does not exist; how and why our eyes, and those of countless other life forms on earth, evolved to detect and discern that which does not exist.
    If color is not intrinsic, not information or intelligence contained in or carried by the light reaching our eyes, if color does not exist objectively, physically but is only a subjective perception of our minds then how and why did life evolved to detect and discern subjective perception?
    How and why do plants like roses and other flowers which do no have a mind or perception have and use color a subjective assigned perception? How do insects and fish as well as simpler animals detect and use color? They do not have minds and only minimal brains, are not conscious according to most and only respond instinctively. How do they respond to a subjective perception which is beyond their abilities? Why is there such a thing as bio florescence?
  9. Jan 12, 2004 #8


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    Life evolved so as to respond to elecrochemical signals from light sensitive cells. Initially just a signal this side is lighter, that side is darker, but a big, big advantage to an organism when all the other organisms couldn't tell light from dark.

    So it evolved, not according to any plan, but according to the momentary advantages that could be had, and eventually we got to eyes (about seven different basic designs of eyes), and mammal vision, and primate vision, and human vision, and our sensation of the frequency spectrum comes to us as color. It's still a bunch of electrochemical signals coming in, being processed into other patterns of neurochemical signals, and so on. Just how these bits of neurochemistry generate RED is unknown, but it's not a category problem, it's just a complicated contingency.
    Last edited: Jan 12, 2004
  10. Jan 14, 2004 #9
    My point is that life responded to take advantage of what was already present. To life frequency is color. Life also uses color even if it does not have eyes to see it or a brain to perceive it.
    With or without a plan, life is opportunistic and uses whatever is available. It does not invent or create it's environment but response to it. I do not see how life could evolve to see color unless it was already present and intrinsic to it's, life's surroundings.
    Physically different colors have different characteristics and properties such as transmission, reflection and refraction. Color is information and carried as the frequency or wavelength of the light or photons. We seem to be confusing the signal or information with the medium of transmission just as the frequency of the carrier of a radio wave is not as important as the information carried by the modulation of the radio wave. However, the carrier is essential for the transmission to take place at all. Color is the important information carried by light. We measure and discern the color by measuring or discerning the frequency of the light. I would be just as easy if not easier to use colored filters or prisms to measure the color of the light without ever determining the frequency.
  11. Jan 16, 2004 #10


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    sight or smell - not both?

    Just to mention a recent report I read - apparently there is some observational data to support the hypothesis that colour vision evolved in humans at the expense of the sense of smell (colour vision is rare among mammals, and most mammals have a considerably more sensitive sense of smell than homo sap's). It's as if the relevant constructor kit for the brain has pieces that can be used for one or other sense, but not both.

    If a person has defective vision from birth - cones that are non-functional, for example, or only rods plus one type of cone - can they perceive colour? What if such a person also had synesthesia?
  12. Jan 17, 2004 #11


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    But that shows color is not an actual property of the light itself. Otherwise, there would be no color in the absence of light - which is clearly not the case.
    No one says color does not exist. It is merely not a property of light itself. Why the ability to perceive different colors evolved should be obvious. Vision is probably the most important survival tool we have. Without it, we are blind and vulnerable. You can be mystified by the experience of color all you want, but it is still certain that color is not a property of photons.
    Last edited: Jan 17, 2004
  13. Jan 20, 2004 #12
    What it shows is that the brain can be stimulated into perceiving color just as it can be stimulated to perceive oder or other sensations and memories as well as moving muscles. It has nothing to do with the subject at hand. We agree that the frequency of the light is detected and percieved as color in the brain of humans. That frequency is a property of the light entering our eyes and determined by a number of different things.

    Scientist by studing light can determine the temperature of the emitting body, its chemical composition and the chemical composition of the medium through which the light passed. Science can also get an indication of the relative speed of the emitting body all by studying the frequency (color) of the light.

    This is all information that is carried by the light and is intrinsic to that light. Our eyes are no different from the instruments of the scientists. Our eyes detect the intrinsic frequency (color) of the light and send this information to the brain where it is perceived to be what it in fact is, color.

    If, as you and others say, color is not a propery of light but is only a perception within our minds, then color is subjective and thus does not exist in the objective material realm but in the mental subjective realm. It has then no physical reality.

    You seem to be concerned about human perception only. What about the rest of life that uses and responds to color including life that has no central nervous system to perceive of anything. Where and how could it develope color without having any means of perceiving it unless color is a property of light, intrinsic or not, and a property of its environment?

    It is certain, however, that color is determined by the frequency of photons and that is certainly an intrinsic propery of photons. The frequency of photons is determined by its intrinsic energy. The more energy a photon has the highter the frequency. The less energy the lower the frequency. I'm sure that you know this. All of this, however, is why I say color is intrinsic, because of the physics involved and that fact that life evolved to passively detect this physical value of light already present in its environment. I don't see how it could be any different. Life responds to it's physical enviroment. It does not assign values to it. We humans can and do assign values to vertually everything but that is a human trait and not necessarily a common trait of all of life on earth.
  14. Jan 20, 2004 #13


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    No, the brain does not detect the frequency of light directly at all. By the time the image is processed (where color is perceived) the brain is dealing with information running through the visual cortex. The light is long gone, and doesn't even make it past the retina.
    So? We already know there is a correlation between the frequency of light and perceived color, but there is no direct perception of that light. The light hits the retina and is gone. The data (spatial and frequencies) in the retina is then converted into an electrical signal and sent over to the brain for processing. As I said, the important thing here is that by the time color is perceieved, the light that hit the retina is long gone. Color cannot be a property of photons because they have nothing directly to do with the experience of it.
    As I said, the original light is gone. The experience of "color" has nothing directly to do with the light that strikes the retina.

    What is real, is the frequency of the light and the retinal spatial pattern.
    This is the same debate about all qualia in general. One approach argues that the physical brain state involved in the perception is equivalent to the experience itself. Others claim the experience is an emergent property of the brain state. But at any rate, that argument is irrelevant. The facts clearly show that color only exists in the mind, regardless of how one wants to explain conscious experiences.
    They respond to light, not color. Plants will respond to light of various frequncies, but with no brain they do not perceive color. It's that simple.
    We've already established that light itself does not have color, so the question of how qualia works or evolved in the first place is not the point.
    That isn't even an intelligent position to hold. The fact that we can experience color without any light striking the retina demonstrates that it exists independently of light. As such, there is no reason at all to think that photons have "color" as a property. The same applies to all qualia. For example, the experience of smell can be generated without there actually being a nearby object to smell.

    Suggesting color is a property of photons is just as silly as suggesting that particles posses "smell" as a real property.
  15. Jan 20, 2004 #14
    It takes a light wavelength of 700 nanometres for us to see the colour red. Is there any evidence that other 'tri-color capable' mammals see a vastly different hue (say cyan) at 700 nm?

    If it can see colour at all, it wouldn't surprise me if a fish sees the ocean very differently. It could be seeing red for all I know, and there's no way to ever find out for sure. I guess there's even the chance that other creatures could be experiencing new colours we've never seen before!
    Last edited: Jan 20, 2004
  16. Jan 20, 2004 #15
    Well just call me silly then. Esters possess odor or have the property of oder as do phermones etc. Wamt to discuss oder as being intrinsic, i.e. have physical properties which are percieved as odors?
    Same arguments apply.
  17. Jan 20, 2004 #16


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    Yes, the same arguments apply. Like color, it can be demonstrated that other smell can be generated without any actual smelly object being present. This shows beyond a reasonable dount that it is all in the brain.
  18. Jan 21, 2004 #17
    I'm going to try a different slant strictly from our human view.
    We are mental beings. Everything we know and do starts in the mind/brain. our only contact with the physical world in which we live is through our senses, sight, sound, smell, taste and touch.
    All the information that we receive from the world is through those senses and they are all passive. That is to say that they are receptors only not transmitters.

    Assuming that the objective, physical world actually exists and that our senses give us a more or less real and accurate model of the real world then what our senses do is receive information about this world. This information is not perceptions nor mental constructs or fabrications of the world but an accurate model of the world in which we live, within the limits of our senses and our instruments.

    This information is carried to us via light, chemicals etc. This information must be real and exist outside and independent of ourselves. The most obvious ways that this happens is through sight, sound and smell. One of the forms of information is color a property of light associated with wavelength. Light has other properties like intensity, purity that also give us information. This is intrinsic to the light our eyes receive or else it is an illusion of perception originating in our brains such as dreams or hallucinations. The same is true of sound and smell.

    It either is information and thus intrinsic or it is illusion and is not information but garbage. Of course if one is an idealist none of this true as the world is only a mental construct anyway and the only reality is within the mind. So all of you idealist can just ignore all of this just as you ignore all of reality. If one i9s a materialist then all of this has to be true or information theory and all of science it bunk and illusion. If one is someone like me then your just confused about everything and must ponder endlessly about everthing and wonder what the hell this is all about.
  19. Jan 21, 2004 #18


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    No need to post a lot of text, just deal with the facts. As I pointed out, it is a fact that qualia like color exist without light hitting the retina at all. This demonstrates beyond a doubt that the experience of color does not involve light directly at all. You have not provided an answer to this fact, and until you do you have no argument.
  20. Jan 21, 2004 #19
    Eh, I have answered that claim three times in three different posts.
    I even gave other examples of color perception without light being present.
    Very simply put our eyes can and do detect color.
    Our retina converts the light into electrochemical nerve impulses.
    Our optic nerves carry this encoded information to our visual cortex where they are perceives as visual colored scenes, a perception model of the real world.
    Our brains are wired to convert electrochemical nerve impulses into visual perception.
    If we stimulate the visual cortex with an electric probe we are simpling substituting and artificial signal for a real signal and our brain has no choice but to "see" that input as a visual perception, color. It is the same way for dreams mental images and hallucinations whatever their cause.
    Stimulating the brain only proves that the brain can do what it evolved to do. Given the proper signal or stimuli in the proper place simulates a signal input from the area or sense connected to that area of the brain. How else would you expect it to work?
    If we couldn't stimulate the brain into such perception it would prove that our understanding of the how the brain works is all wrong.
    If we were blind or color blind and stimulated the brain into seeing color then we would again have a problem with our theories.
    None of this has anything to do with whether color is intrinsic or assigned.
    I say simply that color is intrinsic, external and informational, that is a property of the light entering our eyes that eventually becomes a perceived model of reality in our minds.
    Our minds do not create the color nor does it perform a paint by number routine creating a colored picture in our minds; but, replicates and models what our eyes see.
  21. Jan 21, 2004 #20


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    But you haven't addressed that this fact demonstrates that the perception of color has nothing directly to do with light itself. As such, your claim that photons have color as a real property has no substance.
    Here is the crucial part you've missed: The signal the reaches the brain is not the light the strikes the retina! The light ends in the retina. What ends up in the brain to be processed is something else, and from that we can see color and the frequency of light are not the same thing. Address that point.
    It has everything to do with it, because it clearly demonstrates the light has nothing directly to do with the perception of color. If you agree on that point, then I don't see any basis for claiming color exists outside the mind. You cannot argue that light causes color, because as I said numerous times, the light ends in the retina. The perception happens in the visual cortex (primarily)at which point the original photons no longer even exist. That is the point you are not addressing.
    Again, you're not addressing the fact that the brain never interacts with the light. The colorful images we percieve occur through processes that are a result of light hitting the retina, but light hitting the retina is not the same as the processes going on in the brain. Light has nothing to do with one.
    Last edited: Jan 21, 2004
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