Can color exist to a blind person?

[Jonathan]

Now that I have a few extra minutes, I wanted to come back and address one of Poindexter's statements. He wrote:

Interesting. I've noticed an odd strain of old-fashioned populism in contemporary Objectivism that wasn't there when Rand was alive. Here, Jonathan avers that because lots of non-specialists make similar kinds of associations between their subjective percepts and an objective event in non-controlled, everyday contexts, it follows that these "collective associations" or "socially aggregate associations" must have more objectivity than the associations made by one self-conscious individual like, e.g., Galileo or Pasteur, in a highly-controlled context: such as dropping two balls of different weight from the Tower of Pisa, and putting a piece of meat in the narrow bend of a swan-neck tube of glass. Yet the first shattered the Aristotelian notion (which everyone simply knew to be true) that objects of different weight fall to the earth at different rates; and the second destroyed forever the Aristotelian notion (which everyone simply knew to be true) that living things are generated spontaneously out of dead matter.

So much for the "special" objectivity of collective percepts by aggregates of non-specialists in multitudes of everyday contexts. Objectivity and rationality are not established by any sort of process of enumeration or counting.

My comment had nothing to do with the quantity of viewers as an aggregate, or collective associations, but with the fact that the human context is one in which we, including Poindexter, experience objectively measurable color associations on a continual daily basis, where in contrast, the method that he proposes is something that we rarely, if ever, experience.

Our daily associations of temperature and color are not, as Poindexter claims, "subjective." We can, and continuously do, objectively compare color temperatures using our sense of vision combined with our sense of touch. We can, say, feel an area of the ground which is in shadow, and, in comparison, we can feel an area that is in sunlight. We see that the shadowed area is more bluish in color than the sunlit area. We see that the sunlit area is more golden in color. Thus our associations of color and temperature objectively correspond directly to factual reality.

So, these associations of temperature and color in our daily lives have nothing to do with "socially aggregate associations," but are examples of our objectively measuring temperatures and colors of objects using our senses, as well as thermometers, color densitometers and other equipment if we prefer to be even more objectively accurate than what our senses can provide.

So, contrary to Poindexter's implication that (like the shattering of Aristotle's false notion of free-falling objects) the notion of temperature and color association based on our everyday experiences has been shattered, the black body method has only identified the fact that one color may be objectively associated with a different temperature in one context than it is in another -- blue is objectively measurable to be comparatively cool in the normal human context, where it is objectively measurable to be comparatively hot in a specific context which humans don't normally experience.

J

[We Erred Rand]

>>I reject your arbitrary denial. You seem to want to believe that only the scenario that you've proposed is duplicable, or that since it might be the easiest to duplicate, it is therefore somehow the only objective method of identifying, duplicating and communicating color. If so, you're a fool.

I reject your rejection of my denial.

No two qualitative experiences -- sunsets, cloudy days, navel oranges reflecting sunlight that has first been reflected from a sandy beach, etc. — can ever be measurably alike. They can only be "similar" or "close enough for practical purposes".

>>>Um, a heated black body IS a lighting condition.

Um, a heated black body is a lighting source, not a lighting condition, which refers to the ambient light that might surround the source itself, as well as the researcher: e.g., overhead fluorescents in a laboratory; reflected skylight from outdoors; etc..

>>>Weather conditions are merely identifiable and measurable particles between a viewer and a black body.

And they have no effect on how a black-body incandesces when heated to 3200K. Moreover, they are (as explained below) based on random, stochastic processes in nature; hence, they are inherently non-reproducible (because no two random, stochastic events are exactly alike).

>>>The point, Poindexter, is that in any set of duplicable conditions, the same color will be achieved.

The point, fido, is that the only duplicable condition that objectively exists for color is to heat a black-body until it incandesces and to correlate the color with the temperature.

>>>Anyway, ease or difficulty of duplicability is irrelevant.

The point is not that sunsets and reflections off of beach sand are difficult to duplicate. The point is they are impossible to duplicate in principle.

>>>And a blind person could duplicate more complex conditions and produce the same color results that someone else had produced with the same conditions.

How so? Impress us with a hypothetical.

>>>They're not subjective criteria, but imprecise or approximate criteria.

They're imprecise and approximate on account of their being subjective. "Subjective" and "imprecise" are not mutually exclusive.

>>>Again, that's an arbitrarty assertion. I don't accept your arbitrarily denying duplicability to all scenarios except your favorite one.

Then you don't accept reality.

The sun is always in a different position moment to moment, even at the same time of day and exactly one year apart; its original position in the first sunset is non-reproducible because there is no universal stationary point by reference to which we could, even in principle, haul the sun back to its original position in order to duplicate the sunset we had a year ago. The rotation of the earth is not exactly the same. The position of the sand on the beach has shifted. The cloud pattern (and other weather events) during the sunset is a non-repeatable random event based on stochastic processes in molecules of water vapor. These are non-reproducible in principle.

>>>in the first (the black body scenario), the only element of color that you are reproducing is hue,

Alas, that's a physical impossibility. Black-body incandescence always emits a continuous spectrum. To emit a continuous spectrum means that all colors are achievable and reproducible at some specified temperature (in other words, there are no holes, or gaps, in the temperatures, and there are no holes or gaps in the various colors that are emitted at each of these changes in temperature). What an incandescing black-body does is to emit color, not hue, but color; i.e., something with all three dimensions of hue, value (brightness), and saturation (purity). "Hue" is not a synonym for "color" but a term referring to the generic family name of a group of similar colors, i.e., the hue called "red" doesn't exist, per se, as it means "the family of reds", which would include, "dark ruby red," "medium rose red," "light red," "dull red," "brick red", etc. "A red hue," just by itself, with no brightness and no saturation doesn't exist except as an abstraction, and therefore cannot be emitted from an incandescing black-body.

Same with "warm beige." It corresponds to some point on the continuous spectrum from an incandescing black-body. If it can appear on a beach in Miami from the concatenation of factors (many of which are unknowable), it can be achieved on the black-body at some temperature.

[Jonathan]

The point, fido, is that the only duplicable condition that objectively exists for color is to heat a black-body until it incandesces and to correlate the color with the temperature.

Technically, it is not precisely duplicable. Slight impurities, which are physically impossible to remove, can result in massive differences in color. Therefore, if we employ the level of precision that you apply to all other scenarios, even your favorite scenario is not duplicable.

Black-body incandescence always emits a continuous spectrum. To emit a continuous spectrum means that all colors are achievable and reproducible at some specified temperature (in other words, there are no holes, or gaps, in the temperatures, and there are no holes or gaps in the various colors that are emitted at each of these changes in temperature).

No, it doesn't mean that all colors are achievable and reproducible. The fact that the word "spectrum" is used when describing the black body scenario doesn't mean that it is a reference to the entire visible spectrum, but only to a specific and limited spectrum. An incandescing black body in a laboratory experiment is not capable of creating all of the visible hues, including greens and magentas (the fact that it produces whites logically requires the absense of two opposing hues).

Here's an image of the Planckian locus:

See the black curve? It represents the colors that are visible from a black body at the temperatures indicated. See all of the areas where the black curve isn't? They represent just some of the colors that an incandescing black body cannot create. Greens and magentas are not achievable. Nor are unsaturated or darkened or lightened versions of any of the colors on the chart.

What an incandescing black-body does is to emit color, not hue, but color; i.e., something with all three dimensions of hue, value (brightness), and saturation (purity).

I'm glad that you included "brightness" and "purity" parenthetically. Do you understand what those terms mean? Do you really not realize that an incandescing body can produce only one level of brighteness per temperature and at only one level of purity? It can't create mixtures of hues, and it can't create tints and shades of hues -- it cannot produce greenish grays, dark orche gray browns, slate grays with just a touch of cyan, etc. So, not only can't it produce all of the colors that I indicated on the Planckian chart, but it also can't produce unsaturared or lightened or darked variations of any color in the entire visible spectrum.

"Hue" is not a synonym for "color" but a term referring to the generic family name of a group of similar colors, i.e., the hue called "red" doesn't exist, per se, as it means "the family of reds", which would include, "dark ruby red," "medium rose red," "light red," "dull red," "brick red", etc. "A red hue," just by itself, with no brightness and no saturation doesn't exist except as an abstraction, and therefore cannot be emitted from an incandescing black-body.

Jesus. Um, a hue at full brightness and full saturation is generally referred to as a pure hue. A spectrum is one dimension of colorspace. You just don't get it, do you?

If it can appear on a beach in Miami from the concatenation of factors (many of which are unknowable), it can be achieved on the black-body at some temperature.

That's simply not true. Look again at the Planckian locus and all of the colors on the chart that it can't reproduce. In order to achieve a fully functioning color matching system, you'd have to modify the black body method in certain ways so as to add the ability to control value and saturation levels, and to produce greens and magentas.

But you don't even grasp the problem, so you have no chance of identifying a solution. You're totally a Poindexter. You're pretending to be an expert on a subject about which you know very little.

J

[BaalChatzaf]

Blind people can have access to an analog of color by appropriate encoding through the other senses.

One day it may be possible to interface a light sensing device directly to the visual cortex this bypassing the natural eye. That would be an artificial eye which may give a blind person something like the perception of color and shape.

Ba'al Chatzaf

[anthony]

Tony,

It's not pointless to debate others who think in a manner that is vastly different than you do. It all depends on what you want to achieve.

If you want to convince them--with a simple interaction--that your way is right and all their years of thinking up to now is seriously flawed at the root, I guess it is pointless. That's a hard sell to anyone--even to you.

But if you want to be more selfish, if you want to check your premises to test your thinking, these people will throw stuff at you that you will not come up with on your own. Some of it will get in and hone and polish your views with rich nuances. Some of it will make you actually change your views by correcting mistakes. And some of it you will reject outright.

Think of this. If you want to use the "identify then evaluate" system of thinking, a discussion with such people will provide you with what they think in their own words, not in the words you would attribute to them according to your frame.

I believe this kind of identification is valuable when you disagree and are certain. You can use it for all kinds of things. You can find common ground easier. You can play gotcha (if you're feeling ornery). You can study thinking and valuing processes as epistemological examples. You can see common patterns across very different bodies of ideas and approaches. Lots of things.

There's a whole lot of good that you can obtain from a discussion--yes, even of metaphysics, conceptualization and all the rest--with a person who does not think as you do.

The key is goodwill.

If you discuss important ideas with a person of goodwill, the value is tremendous. If you discuss these things with a manipulator or conceited fool, I agree it can be fruitless (although, even then, since I am studying human nature, persuasion techniques and propaganda, such a discussion can be valuable as a real time case study).

If you are centered and secure in your own thinking, it's great to have really smart people of goodwill around who disagree with you. In fact, I like having people around who are smarter than me in general.

There's a price. No one likes to look at another and feel dumber. That's uncomfortable. But I do it anyway. it makes me raise my bar. And maybe my perspective will shed light on something in their thinking, too.

Voila.

There you have a stream of win-win disagreements on fundamentals. The outcome? Individual people of goodwill can and do improve their thinking--at least in terms of perspective.

What could be better?

Preach and ye shall be of barren tribe. Think and the world floweth with riches.

(How's my olden style? Huh? Huh? Think I'm ready to do a sacred book of aphorisms? )

Michael

Michael,

Hm...

Hah.

Agreed!

(Good thoughts).

[Frediano]

When we are awake, we receive real-time immediate sensory stimulation via our eyes. We see things in color.

When we are sleeping, with our eyes closed, at night, in the dark, we dream. Our dreams to us may not be logical but many of us dream in color, and in fact, mostly perceive our dreams as real while we are dreaming, (Not always, but often.)

This is an assertion; it seems that our brains have both the ability to process real time stimuli ('reality') as well as playback of past reality/memories that are not limited by physics or anything real. We imagine; what goes on in dreams is not simple playback of reality from a high fidelity recorder or memory; our brains have the ability to 'mess' with out memories, and present a 'playback' of our -perceptions- of reality that is messed with, far beyond false coloring, but with totally imagined actors and actions-- like a 'movie' being presented to -something- our perception engines. That which -recieves- the stimuli presented by either a] reality or b] our memories or c] our imaginations.

We have the same eyes. We have the same stimuli collection organs.

My hypothetical experiment (I can't imagine how it can be done) is, with this model, how would we ever demonstrate to each other that each of our 'perception engines' is seeing the same 'technicolor' palette of reality?

We for sure are able to freely deviate with out dreams and imaginings. Why would the same not apply to our 'false coloring' of the stimuli presented to our individual 'perception engines?'

And if we think that isn't possible becuase we have the 'same identical' wetbits, then why do some of us prefer chocolate ice cream over vanilla, and others, vanilla over chocolate? After all we have identical wetbits.

We clearly don't. My question in, how would we design an experiment to verify that we're all watching identically colored 'movies' of reality on our invidula perception engines?

there is no consequence if we are not; if there were, we could identify the consequence and design the experiment.

Hot/cold isn't it; if from the moment of your birth, you associated 'fire' with hot and 'cool water' with cool, then whatever color from your personal reallity false coloring color pallette you mapped to 'fire' would be a 'hot' color and whatever was associated with 'cool water' would be a cool color.

We are stuck, forced to describe what we 'see' only by comparison with external objects. "That is a blue book....yes, that is a blue book." --- which says nothing about what our respective perception engines 'movies of reality' would look like if it were possible to percieve those movie screens side-by-side (by what? a third perception engine...)

For all we know, each and everyone of us has independent color palettes that don't even overlap. We color reality because we must. We do it consistantly because that is what lets us function in the world. If every day we woke up and our color palette was scrambled, we'd lose our minds. We color reality, and we live with it.

The question is, do we all color reality the same way? I don't know. But who does?

In fact, because we don't know and can't tell...it has no consequence at all. If it did...we could answer the question.

[Frediano]

"Even in the womb babies can tell the difference between light and dark. And at birth, they see shapes by following the lines where light and dark meet. Yet, they are several weeks old before they can see their first primary color – red."

Are we all seeing the same 'red?' Or is the above describing a fully programmable perception engine filling in its programmable color palette?

Do we all have the same identical aesthetics? Is there a One True Aesthethics? Are we all supposed to retch when we see yellow-green next to pink, or do some people like yellow-green next to pink, and others do not?

If we have identical color palettes in our reality painting perception engines, and have the same wetbits, then why do we have different aesthetics? There are other ways to explain varying aesthetics than unique color palettes. My question is, how do we prove that we don't have unique color palettes? (We can only prove that we have externally consistant color palettes. "The book is blue...yes, the book is blue....and tomorrow, the book is still blue, and we both still agree...but have not answered my question."

[Frediano]

Why pose this hypothetical? Because if we do 'manufacture' color in our perception engines, then a blind person could as well.

Might as well ask, "Can a blind person dream? Can a blind person imagine? Can a blind person draw?"

Some have run experiments with the blind and congenitally blind regarding their dreams.. There might well be a difference in the 'visualizations' of the blind and the congenitally blind, but that observation could be influenced by prefernence for other modes of perception -- those actively exercised. There seems to be a preference with the congenitally blind for aural dreams, for example. But blind people 'visualize' -- and even draw those visializations. What is their process of 'visualization' to drive their drawing.

What does it mean to 'visualize' if not some processing of stimuli by our perception engines?

Once we've programmed our wetbit perception engines, red is red.

So I wonder; do we all program the same colors when we are three weeks old, etc., or do we simply start programming them and move on?

Some might claim to know. I don't.

[BaalChatzaf]

Some people do not see in color. There is an extreme form of color blindness where there is only degrees of light and dark.

When we are awake, we receive real-time immediate sensory stimulation via our eyes. We see things in color.

[We Erred Rand]

>>>My comment had nothing to do with the quantity of viewers as an aggregate, or collective associations, but with the fact that the human context is one in which we, including Poindexter, experience objectively measurable color associations on a continual daily basis, where in contrast, the method that he proposes is something that we rarely, if ever, experience.

Fido roasts his dogfood over a campfire and therefore asserts (based on nothing but his immediate narrow experience) "fire is warm; fire is red; therefore, red is warm."

Fido was later adopted by Billy, a city boy with no experience of campfires. Billy likes to eat strawberry popsicles. For him, "strawberry popsicles are cool; strawberry popsicles are red; therefore, red is a cool color." Moreover, Billy makes himself a glass of hot cocoa by first heating some milk in a pot on a gas stove. When he lights the stove, the little flames of the burner are blue. "Stove flames are warm; stove flames are blue; therefore, blue is a warm color."

Since there are as many contexts as there are individual Billys and fidos, to say that each is "objective but contextual" is to dilute the meaning of the word "objective" to the point of drowning it completely. Much better simply to say that the associations between a color and objects, or color and processes, is subjective. This makes sense because color itself is subjective, existing only as a percept in the mind of the perceiver.

>>>An incandescing black body in a laboratory experiment is not capable of creating all of the visible hues

, including greens and magentas

Not quite. There are rare green stars (beta Librae), and stars are considered to be approximately ideal blackbody radiators.

There are even magenta stars: Brown dwarves of the T-class.

You're a sick puppy, fido. You claim that many ordinary folks making many ordinary associations make statements about color that are "more objective" than a few statements made by a few researchers engaged in highly-controlled contexts in a laboratory. Then you haul in the CIE color-perception chart, which was put together by a small group of researchers originally in 1931, based on an even narrower, more tightly controlled context than Lord Kelvin's.

What's especially funny about this is that the CIE chart was originally constructed by means of color-matching experiments using 10 observers (all of them sighted, of course! And all of them who claimed they had "normal" color vision, though I don't believe the original researchers actually tested them for that), who were tasked with matching colors on one side of a screen with reference colors provided by the narrow group of researchers on the other side of the screen. The field-of-view of the observers was restricted to 2-degrees (in the belief that this angle-of-view was where the retinal cones had the most sensitivity within the fovea). The color-matching experiments had to be redone at least twice, first with a 4-degree field-of-view, and then a 10-degree field-of-view. There's still no universal agreement which field-of-view is "objectively" the best representation of human color perception.

Sounds like an even more artificially-constructed arbitrary environment than the one used by Lord Kelvin, which you claimed was arbitrary. And in Kelvin's case, there was no matching of colors; there was only a correlation between a color (whose perception obviously is subjective) and a temperature reading (which is objective). That's why a blind person could recreate a color requested of him by simply gaining knowledge of his Kelvin thermometer on a blackbody radiator; while the CIE color-matching chart would be meaningless to him for the simple reason that he needs to see it in order to get any useful information from it. The CIE chart is essentially a database of human subjective responses to color (via matching tasks) that is taken to be the "normal" response of "most" human beings everywhere. Useful? Of course. More objective than Kelvin's controlled situation? Of course not.

Color-matching between two colors must be inherently subjective, as it requires perception of color. Color-correlation between one color and one temperature reading is inherently objective . . . it could even be done by a blind person, and requires only the ability to get information from a thermometer.

Your master needs to take you to a vet, fido. You're clearly suffering from the philosophical equivalent of parvo-virus.

[Jonathan]

>>>An incandescing black body in a laboratory experiment is not capable of creating all of the visible hues

>, including greens and magentas

Not quite. There are rare green stars (beta Librae), and stars are considered to be approximately ideal blackbody radiators.

Earlier you were claiming that heated black bodies always produce the same color at the same temperature. But now you're saying (apparently without realizing it) that a black body could produce either white, pinkish-white or greenish-white at the same temperature!

There are even magenta stars: Brown dwarves of the T-class.

They're not actually pure magenta, but rather a slightly magenta-ish-tinted version of white -- and, like greenish-tinted white stars, they're examples of the imprecision and the wide range of colors that can occur at the same temperature: they are examples of the black body method having a wider range of imprecision than the method of two people using suntans and navel oranges as reference. They demonstrate that our hypothetical Alaskan and Floridian would have a much better chance of matching a beige by describing suntans and oranges than they would at attempting to match neutral white by employing the black body method. Using the suntan/orange description they'd at least be within the same family of hues, where using the black body method would have the possibility of producing colors in the exact 180 degree opposite families of hues!

And in Kelvin's case, there was no matching of colors; there was only a correlation between a color (whose perception obviously is subjective) and a temperature reading (which is objective). That's why a blind person could recreate a color requested of him by simply gaining knowledge of his Kelvin thermometer on a blackbody radiator...

But you've already demonstrated (without realizing it) that a blind person CAN'T recreate a color by achieving a specific temperature on a black body radiator: you've claimed that a black body at one temperature can produce any color from a greenish-white to pure neutral white to a pinkish-white. So make up your mind. Which of your two contradicting positions do you want to take: that a black body at a specific temperature will always produce the same color and therefore that it can only produce pure white at 5000K, or that a black body can produce different colors at he same temperature and therefore can create a range of greens, whites and magentas at 5000K?

J

[Jonathan]

Color-matching between two colors must be inherently subjective, as it requires perception of color.

That's not true. Color-matching can be achieved mechanically using filters and a densitometer, including by a blind person.

J

[anthony]

Tony,

It's not pointless to debate others who think in a manner that is vastly different than you do. It all depends on what you want to achieve.

If you want to convince them--with a simple interaction--that your way is right and all their years of thinking up to now is seriously flawed at the root, I guess it is pointless. That's a hard sell to anyone--even to you.

But if you want to be more selfish, if you want to check your premises to test your thinking, these people will throw stuff at you that you will not come up with on your own. Some of it will get in and hone and polish your views with rich nuances. Some of it will make you actually change your views by correcting mistakes. And some of it you will reject outright.

Think of this. If you want to use the "identify then evaluate" system of thinking, a discussion with such people will provide you with what they think in their own words, not in the words you would attribute to them according to your frame.

I believe this kind of identification is valuable when you disagree and are certain. You can use it for all kinds of things. You can find common ground easier. You can play gotcha (if you're feeling ornery). You can study thinking and valuing processes as epistemological examples. You can see common patterns across very different bodies of ideas and approaches. Lots of things.

There's a whole lot of good that you can obtain from a discussion--yes, even of metaphysics, conceptualization and all the rest--with a person who does not think as you do.

The key is goodwill.

If you discuss important ideas with a person of goodwill, the value is tremendous. If you discuss these things with a manipulator or conceited fool, I agree it can be fruitless (although, even then, since I am studying human nature, persuasion techniques and propaganda, such a discussion can be valuable as a real time case study).

If you are centered and secure in your own thinking, it's great to have really smart people of goodwill around who disagree with you. In fact, I like having people around who are smarter than me in general.

There's a price. No one likes to look at another and feel dumber. That's uncomfortable. But I do it anyway. it makes me raise my bar. And maybe my perspective will shed light on something in their thinking, too.

Voila.

There you have a stream of win-win disagreements on fundamentals. The outcome? Individual people of goodwill can and do improve their thinking--at least in terms of perspective.

What could be better?

Preach and ye shall be of barren tribe. Think and the world floweth with riches.

(How's my olden style? Huh? Huh? Think I'm ready to do a sacred book of aphorisms? )

Michael

Michael,

Hm...

Hah.

Agreed!

(Good thoughts).

Michael, I was doing some thinking about your post, and while I still believe you put out very good thoughts - I do also think it is better suited as a general position you regard deeply, and a little unfairly directed at me personally.

One of your gentle remonstrances to we unruly bunch of O-ish types.

I'm in the choir on those points.

See, I already have often publicly and privately myself said, thought or enthusiastically supported most of those thoughts;

Selfishness accompanied by goodwill; the value here in extending oneself to find more ways to explain one's case, when confronted with contesting ideas, always presented somewhat differently; identifying before judging (a fine one of yours); as well as puzzling over the Big One - of why people do 'think differently' (at the highest levels of reason, that is.)

Though the 'win-win' you speak of, I confess is not so easy...

Good will :- Now I did indeed say "it's fruitless discussing" such'nsuch with individuals who self-identify (or, I have assessed - after a while) with certain convictions or certain methods of reason. I probably lack the light touch, and definitely the academic style - but no matter how much it would be good to find some commonality, it usually doesn't work. It has to be a two-way street. You must know of the down-spiraling of discussion that usually ensues when you understand and acknowledge another's premises - but they won't reciprocate the same respect back at you? All this does not signify that I won't discuss other topics with them, or that I think they are lesser as intelligent humans, or that I don't have a continuing sense of good will to them. E.g. I've known and found some incredibly good character in religious people - and even, sometimes - I hate to admit it - among collectivist/socialist types.()

Honesty and integrity when I see them, get my immediate goodwill despite other disagreements.

There is an error in equating diplomacy/civility with goodwill, I think. This last is of much higher

magnitude to the others. As for my blunt reactions sometimes, because of exasperation and impatience, they shouldn't be taken as a sign of ill-will.

[Jonathan]

Poindexter,

For the sake of simplicity and clarity, let's cut to the chase.

Here's the image of the Planckian locus once again:

See the color green in the very upper left corner of the image? Please specify at which precise temperature you imagine that the locus abruptly veers off of the curve shown and extends to that corner. At what temperature is that color of green produced by a heated black body? See the cyan color in the very lower left corner? Please specify the precise temperature that you image the path of the locus abruptly veers off of the curve shown in order to extend out to that corner of the chart. At what specific temperature do you imagine that the cyan color in the corner is produced by a heated black body? Do you see the tick marks on the bottom edge of the chart? See the fourth tick mark from the left (which is also the third from the right)? At what specific temperature do you think that a heated black body produces the color that is present at that tick mark?

Why do you imagine that the curve is not shown veering off to those points? Please identify how you would correct the path of the curve so that it represents the creation of all of the colors that you assert that a heated black body can create.

J

[We Erred Rand]

>>>That's not true. Color-matching can be achieved mechanically using filters and a densitometer, including by a blind person.

Wrong. The blind person would still need to see a color as a reference, first to calibrate the densitometer, and then to compensate for color-constancy issues and metamerism between similar hues under different lighting sources (which would incorrectly tell the blind person the hues were different), or different hues under different lighting sources (which would incorrectly tell the blind person the hues were identical).

Densitometers measure density, not color.

You earlier made an arbitrary assertion about "duplicability":

Quote

>>>. I don't accept your arbitrarily denying duplicability to all scenarios except your favorite one.

The context was that you claimed the entire beach scenario was perfectly duplicable in principle irrespective of technical difficulties in moving the sun, earth, clouds, etc., back into their original positions at "t=0". I pointed out that this is impossible in principle, and not merely technically difficult: the exact position of the earth at "t=0" can never be recaptured at a later time "t=n" because there is no fixed point in space relative to to which you could claim the earth had been returned. The earth could be in the approximate position relative to the sun after a year; the sun-earth system could be in a similar position relative to the rest of the solar system after "x" years; the solar system could be in a similar position relative to the Milky Way after "y years," etc., etc., but these would only positions relative to something else; it wouldn't mean the earth was literally in the same spot as it was at "t=0", which is the first condition that needs to be met for your claim regarding duplicability.

Additionally, weather conditions at "t=0" have aspects about them that are stochastic — irreproducible because unique at "t=0" and only at "t=0". Since weather would obviously affect ambient lighting at the beach, that rather means that entire scenario could only be approximated "in the eye of the beholder." That removes the blind man entirely.

Another way of putting this is that there are no blind swimwear photographers (at least, not at "Sports Illustrated"). You mean, you never wondered why?

You made a big deal earlier in this thread regarding the ability to precisely duplicate the beach scenario, maintaining that the problems were merely practical in nature, and not physical or mathematical. Then you ducked the entire issue and never responded.

Still waiting patiently.

[We Erred Rand]

>>>See the black curve? It represents the colors that are visible from a black body at the temperatures indicated.

No it doesn't. You fail to understand how the CIE Chromaticity Diagram was constructed. That line corresponds to blackbody illumination and represents the colors on the chart the test subjects could perceive as white. The middle of the chart, at (x=0.33, y=0.33) is "equal energy white," but anywhere along that line is also "white." The orthogonal lines are "isotherms," which give a correlation between that point and some other color on the chart. The greens and magentas therefore have "correlated color-temperature."

See all of the areas where the black curve isn't? They representjust some of the colors that an incandescing black body cannot create.

Obviously not. If you're looking at the CIE diagram on a printed page, for example, under incandescent illumination, the lime green at the top of the chart, or the cyans, it means those wavelengths are already in white light, and are therefore being produced by heating the black filament to "x" degrees kelvin. The issue in perception is that a blackbody (like a filament) always produces R/G/B at all times and at all temperatures — there are no spectrum gaps, merely different biases toward Red, Green, or Blue. There is no temperature that corresponds to lots of lime-green wavelength sans red and blue at the same time. The lime green wavelength is produced by the blackbody — that's why you see it on the printed page under the sad little bare bulb in your doghouse — but the high amounts of "red" also being produced would cause both the "red" and the "green" cones in the fovea to fire, causing you to see "yellow." Something that absorbs red — a blue-green filter, or a chemical property of the ink used in printing the CIE diagram — would be necessary in order to view the lime green. But if you're seeing the lime green, it's by virtue of the fact that it's already in white light produced by a heated blackbody.

>>>Greens and magentas are not achievable. Nor are unsaturated or darkened or lightened versions of any of the colors on the chart.

By definition, as shown above, they are already "in" white light from a blackbody. That's why you see them when the printed page (or backlit computer monitor) is illuminated. The horseshoe-shaped curve at the top has numbers around it representing the correlated wavelength used to generate that colored light for the test subjects. The exception is not the greens or the cyans, but the "line of purples" at the bottom of the chart, which, as your master could plainly tell you (since you appear to have problems reading), has no single wavelength numbers correlated to it (i.e., they don't even exist in the prismatic spectrum of sunlight. They are "extra-spectral". That means they correspond to no single wavelength, and can only be achieved by mixing two or more wavelengths.

Surprisingly, I was wrong about purple. Unsurprisingly, you were wrong about everything.

Someone should tell your master to clean up the data-dumps you've been leaving on this thread in amusing canine attempts to dodge my replies to your arbitrary assertions regarding precise duplicability of natural contexts such as a beach scene. Someone should really clean those up in a pooper-scooper. As they say in the U.K.: you're fouling the footpath.

[caroljane]

Someone should tell Weird to curb his cravings for gratuitous insult, or he will find himself down in the minors again. Waterboy with the Missouri Mules, maybe.

[Jonathan]

>>>That's not true. Color-matching can be achieved mechanically using filters and a densitometer, including by a blind person.

Wrong. The blind person would still need to see a color as a reference first to calibrate the densitometer and then to compensate for color-constancy issues and metamerism between similar hues under different lighting sources (which would incorrectly tell the blind person the hues were different), or different hues under different lighting sources (which would incorrectly tell the blind person the hues were identical).

Modern color densitometers are self-calibrating, and they compensate for differences in lighting souces.

Densitometers measure density, not color.

Notice that I wrote "using filters and densitometers." Densitometers combined with filters measure color, and they do so very precisely. Modern densitometers include internal filtration. Your approach to discussions appears to be to quickly look somthing up on Google and to imagine that you've learned everything that you need to know.

You made a big deal earlier in this thread regarding the ability to precisely duplicate the beach scenario, maintaining that the problems were merely practical in nature, and not physical or mathematical. Then you ducked the entire issue and never responded.

Still waiting patiently.

But I did respond in post 111. You apparently didn't understand the answer.

J

[Jonathan]

No it doesn't. You fail to understand how the CIE Chromaticity Diagram was constructed. That line corresponds to blackbody illumination and represents the colors on the chart the test subjects could perceive as white.

What are you talking about? Heh. It sounds as if you just read a source of information on a different diagram, not realizing that the information that you were reading didn't apply to the one that I posted. Hilarious.

The middle of the chart, at (x=0.33, y=0.33) is "equal energy white," but anywhere along that line is also "white."

No. It's not "white." And it's also not white without scare quotes. 99% red + 1% green + 1% blue does not equal white. Really. Did you think that you'd wiggle out of your previous errors simply by relabeling everything "white"?

The orthogonal lines are "isotherms," which give a correlation between that point and some other color on the chart. The greens and magentas therefore have "correlated color-temperature."

Yes, the greens and magentas have a correlated color-temperature, which is what I said in post 103 -- "An incandescing black body in a laboratory experiment is not capable of creating all of the visible hues, including greens and magentas (the fact that it produces whites logically requires the absense of two opposing hues)."

"Correlated" means that they are not present individually on the locus. It means that a heated black body can't create green or magenta since they cancel each other out.

Obviously not. If you're looking at the CIE diagram on a printed page, for example, under incandescent illumination, the lime green at the top of the chart, or the cyans, it means those wavelengths are already in white light, and are therefore being produced by heating the black filament to "x" degrees kelvin.

Heh. Earlier you were claiming that the black body method could produce any color, including greens and magentas, but now you're claiming that producing white light is an act of producing all of the colors, and therefore producing white is procuding green or magenta? So if I were to ask you to produce a color that consists of 87.6% magenta, 20% cyan, and 12.84% yellow you'd produce a white at 5000K and say, "It's in there. All colors are in white, so it's in there." You're hilarious.

The issue in perception is that a blackbody (like a filament) always produces R/G/B at all times and at all temperatures — there are no spectrum gaps, merely different biases toward Red, Green, or Blue. There is no temperature that corresponds to lots of lime-green wavelength sans red and blue at the same time. The lime green wavelength is produced by the blackbody — that's why you see it on the printed page under the sad little bare bulb in your doghouse — but the high amounts of "red" also being produced would cause both the "red" and the "green" cones in the fovea to fire, causing you to see "yellow." Something that absorbs red — a blue-green filter, or a chemical property of the ink used in printing the CIE diagram — would be necessary in order to view the lime green. But if you're seeing the lime green, it's by virtue of the fact that it's already in white light produced by a heated blackbody.

Um, are you Victor Pross? I get the distinct impression that I'm talking to Google searches.

J

[Michael Stuart Kelly]

Michael, I was doing some thinking about your post, and while I still believe you put out very good thoughts - I do also think it is better suited as a general position you regard deeply, and a little unfairly directed at me personally.

. . .

As for my blunt reactions sometimes, because of exasperation and impatience, they shouldn't be taken as a sign of ill-will.

Tony,

Good Lord!

The last thing on earth I was thinking at the time was to criticize you.

Dayaamm!

If I were a world-class manipulator, I would have a field day with your unearned guilt.

Believe me, you are one of the good guys. Your guilt is totally unearned. (I detect it when I see you presume a suggestion or abstract discussion is a personal criticism of you, and I have seen you do that several times.)

Life to me is simpler--you are one of the good guys with a really good head.

Period.

The reason I went into what I did is that the purpose of this site is for people to think through their ideas at their own pace and circumstances. This means that it could potentially degenerate into total relativism and moral equivalency,

Yet it doesn't.

One of the reasons is that people who have thought their ideas through on a deeper level than just reading Rand--those who have a constant habit of checking their premises--get a lot of benefit from contrary views. I believe you fall into this category in general.

Yet, we all get tired at times. Me, too. I'm no different. Life (and philosophy) is experienced in waves, not a straight line.

So it is good to be reminded of our values when we get weary.

That was my intent. I might have misread you and presumed this kind of intellectual fatigue where there was none, but, so far, I still think I saw it.

In short, I was giving you a pep talk, not a lecture.

(Also, I did have an an eye to the general reader, who seems to like clear explanations like that, based on the fact that they keep coming back.)

Michael

[Michael Stuart Kelly]

Um, are you Victor Pross? I get the distinct impression that I'm talking to Google searches.

Jonathan,

You suddenly got my attention...

I hadn't thought of that...

Michael

[Jonathan]

Yeah, there are some similarities.

J

[caroljane]

Nah. As I indicated in in #117, it's obvious who our anagramous friend is. Xray figured it out when he first appeared.

[Michael Stuart Kelly]

Never doubt the creativity of a motivated neurotic.

Michael

[BaalChatzaf]

Color-matching between two colors must be inherently subjective, as it requires perception of color.

That's not true. Color-matching can be achieved mechanically using filters and a densitometer, including by a blind person.

J

could you give us a reference to this type of color matching? That would be handy. Thanx