hedonologist

The wavelength we collectively refer to as "red" I will call "wr" and "wb" for the wavelength known as "blue". The "color" you see when you see wr, I will call "yr" (your red), and the color I see when I see wb, I will call "mb" (my blue).

So mb may be the same "color" as yr, for all I know. Similarly, your white could look the same as my black. I don't know what makes mb the "color" it is, I only know one component of the cause, which is the wb. Mb is like a symbol my mind/brain uses to symbolize wb. Objective/material things can be measured, but there is no way to measure mb to compare it with yr, so I would call it a subjective experience and a non-material experience.

If you believe yr could be different than mr, don't you believe in something non-material or subjective?

[ December 31, 2001: Message edited by: hedonologist ]</p>

Bill Snedden

It's an interesting question, and certainly one that has been asked before.

I would say that "color", being a perception of a physical phenonema, is by definition subjective. The wavelength itself is a physical phenomena and is, again by definition, material.

The interaction between the two that takes place in the brain to produce what we perceive as "color" is really the crux of your question. It seems to me that you are really asking if we can be certain that the physical phenomena that produces the perception of "color" is truly objective.

I would say that it matters not whether you perceive yr and I perceive mb for the same physical phenomena (let's say wr). At issue would be the consistency of the perception. In other words, for every occurrence of wr, I should perceive mb and you should perceive yr. If this is the case, then we should be able to say that the phenomena producing the perception (wr) does indeed have objective existence.

Or, perhaps I have completely misunderstood your question?

Regards,

Bill Snedden

excreationist

This shows colours in two dimensions - with hue on the horizontal, and saturation on the vertical. There is also another dimension - luminosity (which ranges from total brightness [white] to the colour to total darkness [black])
Anyway, the colours that have a single distinct wavelength would only be those colours along the top of that chart, ranging from red (infra red isn't visible) to violent (ultra-violent isn't visible either).
"Red" can range from colours that begin to become orange, to those that begin to become purple. (there is a range in the hues)
It can also vary in the saturation, so that less intense red (greyish red) is still red.
And it can also vary in the luminosity where slightly whitish red or darkish red can still be called red.
So it isn't like that only colours that are from an exact wavelength, to an infinite precision can be called red.
The same is true for blue. The hue of blue can vary from slightly purplish blue to slightly greenish blue. It's saturation can vary from intense blue to less saturated or greyish blue. And its luminosity can vary from whitish blue to darkish blue.

Ok, so here you're talking about a specific wavelength that involves a red and a blue. But note that there are other reds and blues.

Yeah, I've wondered the same thing before.

Anyway, here's a quote from <a href="http://ase.tufts.edu/cogstud/papers/quinqual.htm" target="_blank">Daniel Dennett's "Quining Qualia"</a>:

It also talks about colour inversion, where the colours in people's vision is inverted. (What you were talking about)

I think that if a person had colour inversion googles (probably VR googles hooked up to tiny video cameras) for several days, they would eventually take the new colours they see for granted.

Basically people just receive some colour information (like a banana might give the signal "2131233") and the person would associate this information with words - like "yellow". And if they adapted to colour inversion goggles, then they would simply be re-classifying the colour information. It is like how you can adapt to wearing coloured glasses (after a while) and the coloured whites begin to seem "white", etc.

Well in the case of computers, these colours are pure red:
1111100000000000 (16 bit RGB)
111111110000000000000000 (24 bit RGB)
000000000000000011111111 (24 bit BGR)
0, 240, 120 (HSL - Hue Lightness Saturation in MS Paint)
There are also other colour schemes like CMYK (used when mixing paints, rather than light), YUV, and Lab.
So the colours are represented in different ways... so a given sequence of bits could represent opposite colours (this is true in RGB vs. CMY [cyan, magenta, yellow]).
So the information used to represent the colours is subjective.

[ December 31, 2001: Message edited by: excreationist ]</p>

bgponder

Hedonologist:

Correct me if I'm wrong, but aren't thoughts, perceptual experiences, subjective experiences, et.al. reducible to brain states? Therefore they are material. However, we are limited by the hardware. So, if a person has some condition whereby wr is rendered as purple, they have no choice but to "believe" their perception. You could talk to them about red all day long to no avail. But it would still be neural firings you were talking about.

Is that clearer, or muddier?

Peace, cbd, Happy New Year!! Barry

hedonologist

I'm not sure what you are referring to as a physical "phenomenon". Maybe you are referring to yr as a "physical phenomenon", or wr, or maybe something more like a physical correlate of the consciousness of color in the brain, which has yet to be discovered.

Anything I would call physical, I would call objective. I am asking whether the perception (eg yr or mb) is objective or material IOW. You are saying I'm defining color as subjective. How can we have subjective experiences if only matter exists? How can we perceive such subjective things as yr?

hedonologist

I'm not sure what you mean by "reducible". Those things may correspond with brain states, but I don't see how we could have what I would call "subjective experiences" unless we were subjects. Subjects and subjective experiences can't be quantified, thus I think of them as non-material, but more than that, an experiencer (ie subject) is as necessary for the existence of an experience, as material is. Material can't be defined, only the experience of it can be defined. Harmony between memories and unchanging aspects of our experiences, imply the existence of an objective material world. You can look at objective things, but by definition you can't look at your true self. You are the looker, not the seen. I suppose this is why some seem to be more able to deny their existence as experiencers, in a sense, than to deny the existence of matter.

hedonologist

Oh yeah. I forgot we were talking about waves of differing length so there is nothing but an arbitrary standard of what is the bluest blue, etc. That doesn't matter to my point, however. We could talk about any specific wavelength and name it whatever color we want.
So you are comparing yr or mb to info like a number. But it is not info like a number, it is subjective. That is why we can't say for certain wether yr is more like mr or mb.
I would call info in a computer objective, so I'm not sure what you mean. I would say the info used to represent the colors is arbitrary, but I'm not talking about information used to represent "colors" anyway, I'm talking about comparing yr to mb.

I'm still working on a response to the analogy to upside-down. I am boggled by it. While I was working on it I wrote this: I just heard a bunch of explosions and am a little amazed that I didn't realize until now that New Years was coming. No one mentioned it. Then I thought, "Does that make me a year older?" It must be my bedtime. 'Night

excreationist

Well we could each objectively perceive colours in a particular way, but it doesn't mean that colours must be classified or described in a particular way.
So some software deals with colours in the BGR format (with the blue coming first), and others in the RGB format or even YUV. (JPEG files use YUV during compression and decompression)
It can be objectively true that the software is representing colours in those ways, but I don't think there is an objectively correct way of representing colours either on computers or how we perceive colours with our brains.

excreationist

No, I'm saying that for you, red would be a particular firing pattern. e.g. 123901. For me it might be a slightly different pattern. e.g. 2313423.
"That is why we can't say for certain wether yr is more like mr or mb"
Exactly.

As a related example, what about the computer representations for red?
One bit of software might represent pure red as FF0000 (hexadecimal RGB, used for monitors) and another might be 00FFFF00 (hexadecimal CYMK, used for printing). Both are equivalent to one another - none is the "wrong" answer.

Another example is numbers. Say we're talking about the number 7.
Here are some representations of it:
"7", "seven", "VII", "seiben", "111" (in binary), "21" (in trinary)

Well the wavelength of the light is converted into neural firing patterns which can be viewed as a series of numbers. (In artificial neural networks, numbers are used, and depending on the exact configuration of the neural network and what it learns exactly, the neurons will have different numberical values)

You know I keep telling myself that I have to get my hands on some of those glasses... I think I'll have that as my New Year's resolution... (even though it is 7pm, Jan 1st, here) Happy New Year.

excreationist

Another quote about inverting lenses:
<a href="http://www-art.cfa.cmu.edu/penny/texts/VR_Dia.html" target="_blank">Cognitive plasticity</a>
That would be pretty cool - to be able to look at upside-down images and easily treat them as if they are the right way up....