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Thread: Does black exist?

  1. #1
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    Does black exist?

    or is it just our brain crying "insufficient data!"
    "Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."

    Stephen Colbert.

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    Quote Originally Posted by parallaxicality View Post
    or is it just our brain crying "insufficient data!"
    What is your definition of black?

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    Let's say, absolute black.
    "Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."

    Stephen Colbert.

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    I think the point is that if you define "black" as being the result of no retinal stimulation, then it represents an absence of something, rather than a presence. But if you define black as being a quale with equal rank to red, yellow and white, which is what it feels like, then it "exists" to the same extent as those colours, which also have no other claim to existence except what they feel like.
    So the answer to your question depends on the neurological level at which you define "black".

    Grant Hutchison

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    The difference though is that red yellow and white are emitted light at specific frequencies; whether they are literally red, yellow or white they do exist in the real world. Black is the absence of emitted light, so I'm pondering if it exists at all.
    "Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."

    Stephen Colbert.

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    Quote Originally Posted by parallaxicality View Post
    The difference though is that red yellow and white are emitted light at specific frequencies; whether they are literally red, yellow or white they do exist in the real world. Black is the absence of emitted light, so I'm pondering if it exists at all.
    That is why you need to define what you mean by the word "black" (and maybe "exist" as well). Light of frequencies corresponding to those colours exists. Clearly, there is no light corresponding to the colour black. But the colours red, yellow, white and black all have an equal degree of existence.

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    Quote Originally Posted by parallaxicality
    Does black exist?

    or is it just our brain crying "insufficient data!
    Where a universe of 'sufficient data' is said to exist, one still needs a term to describe an absence of data.
    Otherwise the term 'exists' in that sentence, completely loses its meaning and we just zapped the entire universe out of existence!

    In short, its pretty clear that black exists.

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    Quote Originally Posted by parallaxicality View Post
    Black is the absence of emitted light, [...]
    Is that the definition you meant to include in your OP? Where your wrote, or is it just our brain crying "insufficient data!", I took it to mean a lack of visible light perceived by the average human eye. That lack of perception could be due to a lack of visible light being present at all or it could be due to intensity below the detection threshold.[/COLOR]

    so I'm pondering if it exists at all.
    Of course it does. It exists as a term of science and art, a concept, a visual sensation, and as a crayon.
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    Quote Originally Posted by PetersCreek View Post
    .. That lack of perception could be due to a lack of visible light being present at all or it could be due to intensity below the detection threshold.
    Which would be one in same thing anyway, no?

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    Quote Originally Posted by parallaxicality View Post
    Let's say, absolute black.
    The nearest thing to that is vantablack (https://www.surreynanosystems.com/vantablack). This must exist because it is trademarked and patented.

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    Quote Originally Posted by Selfsim View Post
    Which would be one in same thing anyway, no?
    In a practical sense, yes, they would be the same thing. If the definition of black is tied to the human eye, then to the observer, there's no perceivable difference between sub-threshold light and no light at all. But in regard to "absolute black" as the OP stated, I do think there's a difference between 'no light at all' and 'light we can't see but is present nonetheless' when defining/describing objective physical conditions. That's why I'd like some clarification.
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    I think that in a cool underground cavern, and I was thinking of a place like The chamber in Kamiokande, there are so few visible photons that they won’t trigger photoreceptors. In that case there is an effective absence of light from the environment, so it’s like black. However, the visual cortex doesn’t necessarily require outside stimulus to be active, think of dreaming or afterimages for example. So you still would not see nothing.


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    Is this another of those “magenta doesn’t exist” things?
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    Quote Originally Posted by Strange View Post
    The nearest thing to that is vantablack (https://www.surreynanosystems.com/vantablack). This must exist because it is trademarked and patented.
    .. Which has apparently just been trumped according to this recent release:


    Engineers Just Unveiled a New Blackest-Ever Material, Even Darker Than Vantablack.

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    Quote Originally Posted by Jens View Post
    I think that in a cool underground cavern, and I was thinking of a place like The chamber in Kamiokande, there are so few visible photons that they won’t trigger photoreceptors. In that case there is an effective absence of light from the environment, so it’s like black. However, the visual cortex doesn’t necessarily require outside stimulus to be active, think of dreaming or afterimages for example. So you still would not see nothing.
    Hmm .. dunno 'bout that .. whilst under 'twilight' anaesthetics, there's no experiences whatsoever. (I think they effectively 'wipe out' memories of any experiences during the period of anaethesia, also). I guess that doesn't necessarily address the question of blackness though ..

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    Quote Originally Posted by PetersCreek View Post
    In a practical sense, yes, they would be the same thing. If the definition of black is tied to the human eye, then to the observer, there's no perceivable difference between sub-threshold light and no light at all. But in regard to "absolute black" as the OP stated, I do think there's a difference between 'no light at all' and 'light we can't see but is present nonetheless' when defining/describing objective physical conditions. That's why I'd like some clarification.
    I suppose the human experience of 'black' is pretty clearly different from the experience of reading the measurement output of some photon detector (say in some quantum experiment). But both sort of represent the same fundamental issue though .. just at a different scales I think(?)

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    Is 0.999999999... colorless equivalent to totally black?

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    Quote Originally Posted by DonM435 View Post
    Is 0.999999999... colorless equivalent to totally black?
    You could say it is if you your detection threshold is 0.98 or some such...but then you wouldn’t know it was 0.999999999...
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    Quote Originally Posted by parallaxicality View Post
    or is it just our brain crying "insufficient data!"
    Others may have been saying the same thing, but I think you have to distinguish with the blackness of black objects and the blackness in a dark room. The darkness in a black room is from a lack of information-the lack of visible photons means we are not getting adequate stimulation to be able to see. But the blackness of say a panther is from the relative lack of photons coming from the object, and is actually very useful information if you are hoping to not get eaten. So it’s not the brain screaming but rather making a judgment based on the relative number of photons.


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    Quote Originally Posted by PetersCreek View Post
    You could say it is if you your detection threshold is 0.98 or some such...but then you wouldn’t know it was 0.999999999...
    You wouldn't have to. All you'd know - and have to know - is that it is beyond the threshold. Doesn't matter how far - all possibilities are the same.

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    Quote Originally Posted by parallaxicality View Post
    The difference though is that red yellow and white are emitted light at specific frequencies; whether they are literally red, yellow or white they do exist in the real world. Black is the absence of emitted light, so I'm pondering if it exists at all.
    Which just goes to show that it depends on how you define "black". The sensation of "yellow", by the way, can be generated by combinations of wavelengths that contain no individual frequencies you'd class as yellow; and "white" can be generated by all sorts of spectral distributions, which only appear "white" if they're the ambient illuminant, but which will appear distinctly blue or yellow or pink if they're not the ambient illuminant. So I chose that sequence of red, yellow, white, black deliberately, to demonstrate the range of ways in which colour sensations can be produced by an illuminated retina. The fact that you draw a line between white and black is just a definitional choice.

    Grant Hutchison

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    If black means no light, or no colour, then you have the objection that you cannot define a non existence. the impressionists argued over this and I think it was Manet insisted in having black in his pallete. But if you define black as no reflection that seems OK or it absorbs all em radiation or is a perfect emitter, surely a good definition allowing the super blacks and black body radiation.
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    Quote Originally Posted by grant hutchison View Post
    I think the point is that if you define "black" as being the result of no retinal stimulation, then it represents an absence of something, rather than a presence.

    Grant Hutchison
    And even then, it still "exists", which was the question in the OP. To me, positing that black may not exist because it is just an absence of sufficient photons to stimulate retinal cells is like suggesting that a vacuum doesn't exist because it is just an absence of sufficient measurable matter in a given volume.

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    But vacuum does exist. Black is just the human brain's way of signifying nothing.
    "Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."

    Stephen Colbert.

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    Quote Originally Posted by parallaxicality View Post
    Black is just the human brain's way of signifying nothing.
    Ok then .. In a universe of complete and total whiteness, white would signify nothing.

    It seems to me that the absence of contrast in any universe, is what signifies nothing.

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    Quote Originally Posted by parallaxicality View Post
    But vacuum does exist. Black is just the human brain's way of signifying nothing.
    No, it's not. Black provides information about the content of the visual field, in the same way the dog doing nothing in the night-time provided information about the visitor to Silver Blaze's stable, or the number zero gives information that a blank bit of paper does not.
    Absence of a neurological signal from the retina looks different from black, as anyone who has lost a chunk of their visual field can tell you. There's a good reason for your neurocognitive system to distinguish between the two, and to generate the quale "black" to let you know there's an area in your visual field sending few photons in your direction.

    Grant Hutchison

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    Absence of a neurological signal from the retina looks different from black, as anyone who has lost a chunk of their visual field can tell you.
    Really? That's fascinating. I'd ask for elaboration but I don't think that would be possible.
    "Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."

    Stephen Colbert.

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    Quote Originally Posted by parallaxicality View Post
    Really? That's fascinating. I'd ask for elaboration but I don't think that would be possible.
    I can elaborate on it. I have a blind spot on each retina, as we all do. The visual cortex never gets signals from those spots and is programmed to ignore them, so we do not see black spots when looking at a bright field. If a small black spot in the field is projected onto a blind spot, it disappears but the sensation is just whatever surrounding light is present.

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    Yes, questions like "does black exist" or "is a hot dog a sandwich" are often framed as being like "is 2+2 equal to 4 or something else", where our goal is to answer the question as it stands, as if the question were on an exam and had a right answer we are trying to glean. But actually, what is required is significant further clarifications about the intended meanings of the words, and not just "black", but also, "exists"! We are lazy and want our words to just mean stuff, but that isn't how language works, language is much more complex, active, and contextual.

    What's more, language is not used to simply label boxes, where everything either goes into the box, or is left out of the box. That simply isn't how we use language, instead we have classes of quintessential examples of our labels, and then we have a vague concept of "how similar" are various other things to our quintessential examples. So we have a kind of gray scale that goes from "very much like what we mean by that word" to "very much not like what we mean by that word", with no sharp boundaries (in most cases) between what does and does not belong "in the box" of black, or "in the box" of existence. Hence, it takes a great deal of thought and discourse to establish these complex connections, much more than most people are willing to do (and hence they retreat to black-and-white thinking about what either is, or isn't, in the box).

    At this point, many who don't understand language at all will object "but that's just semantics" and dismiss the whole enterprise as a waste of time, missing the essential fact that the purpose of a question like "does black exist" is not to answer the question, but rather, to use the question as a focus toward understanding what our the intentions behind the meanings of our words, and what possible different meanings might we take in different contexts. As a result of that very useful and important exercise, we find we are learning about cognition and vision by thinking about the meaning of "black". And elsewhere we have a whole thread about the possible intended meanings behind "exist," a word we would also have to delve quite deeply into before we could arrive at an answer, and likely a different answer for different intended meanings of "existence."
    Last edited by Ken G; 2019-Sep-22 at 02:10 PM.

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    I'm surprised that no one seems to have mentioned contrast, and the limited ability of our eyes and brains to process it. The letters I'm typing right now appear as black on a white screen. But they actually can't be any darker than what the screen looks like when turned off, which isn't all that black, although blacker than in the CRT days.
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