As some on this board may be aware, there is a lively debate over whether colors exist in the world, or are a psychological entity (“in the head”). We don’t normally debate the same aspect over shapes or sizes. One reason that seems to be is because shapes interact with, and hence constrained by, each other, so the only way to be a skeptic there is if one’s a skeptic about representationism in general. So, assuming the commonsense framework that consciousness is a veridical naive representation of the physical environment with some detectable anomalies(i.e. illusions), colors still seem bereft of a place in the framework of physicalism. At first glance, that seems to be because, unlike shapes, colors don’t seem to interact with, or are useful to, anything but minds (“wear the red sweater”, “pick ripe apples”).
So the question is this:
Are colors causally effacious in non-conscious interactions i.e. any case where a physical transaction hinges on the color of one of the parties with no conscious mediation involved? The color must itself be instrumental, rather than being coincidental.
If the answer is negative, how can physicalism of color be defended?
Interesting take on the age-old problem of universals.
I agree with other-wise that the main issue in the question, as you pose it, is the distinction between “conscious” and “non-conscious”. If a bee (not a beehive, an individual bee) engages in “non-conscious interaction”, then it would appear obvious to me that colour - or, rather, “the spectrum of light reflected by a particular group of flowers” - does exist in this sense. We could also use an artificial system that recoginzes colours, where every aspect, from the camera to the computer to the program that does the recognition, is completely within the realm of the physically determined and, moreover, amenable to mathematical analysis within our current understanding of physics down to (in principle) the atomic level; not even the most vocal proponent of hard AI would claim that such a machine had any degree of “consciousness”.
On the other hand, the generalization over “the spectrum of light reflected from ripe apples”, “the spectrum of light reflected by blood”, “the spectrum of light emitted by a black body at 800 K”, etc, to the single colour, “Red” would appear to be a purely mental process, requiring a mind capable of forming abstract concepts.
The article you posted seems to me to fail to address the fundamental metaphysical question - “Do properties exist independently of substances?”. The authors assume a realist position and cheerfully answer “Yes” to this, then go on to address the question “Does a specific property, ‘colour’, exist independently of its perception?”
In order to follow this debate I had to look up the word “effacious”, and at both Merriam-Webster and Dictionary.com I was unable to get a definition or the suggestion of a proper spelling that comes even close.
Bees are conscious. From my first link in OP: Even given this more restrictive conception of what it is to possess color vision, very many non-human organisms will plausibly possess it. These include most old-world primates, many birds, many shallow water fish, and invertebrates such as bees.
Let’s start with that readily agreed to be unconscious e.g. cameras.
‘efficacious’ is the right spelling. Wonder why I got it wrong. If a Mod reads this, please change all occurences in title and OP.
The million dollar question is Can We? It is very important that ‘color’ has to be the instrument, not wavelength of the impinging photons. Just to make the distinction clear, refer to the various color illusions i.e. checkershadow illusion or the pink/green dots. Presumably, the wavelength of the impinging photons doesn’t change.
I see what you mean - I would therefore take the position that “colour” is a classification imposed on the world by the human mind and human visual system, in the same way that (say) “economic value” (as opposed to “rarity”) is a property imposed on things by human society rather than being intrinsic to them. The optical illusions demonstrate that colour, as we perceive it, is not the same thing as wavelength, and “wavelength” is the only part of the system that doesn’t depend on human visual ability.
So, now I need to defend this position against your arguments and/or the arguments in the article. I’ll read it again and get back to you.
OK, I’ll repeat my primary objection to the article now, focussing on para 3.2.1, the heart of the issue.
The authors assume that a “property” is something that exists independent of any substance to which it’s attached. They assume that, because we can assign properties (in their specific case, “hue magnitudes”) to the objects of our perception, those properties somehow become part of those objects, that it also, in addition to its substantial constitution, now has these properties essentially, that we can isolate and extract and discuss these properties in the same way we can isolate and extract and discuss the atoms from which it’s made.
Again, compare their property of “hue magnitude” with “economic value”. In the absence of a society that uses money, that buys and sells things, “economic value” is an entirely meaningless concept - something isn’t worth money unless there exist a buyer and seller who can perform the transaction. I would argue that “hue magnitude” (or “colour”) is equally meaningless in the absence of a visually-acute being who can percieve the differences in “productances”, to use their term) of the object, and interpret them in a consistent manner.
I would also argue that their (very interesting) discussion of “unique” and “binary” hues demonstrates conclusively that human visual physiology and psychology are the sole determinants of colour, rather than “productance”. They don’t, in my opinion, provide an adequate refutation for this - their argument is both metaphysically doubtful (I would describe myself as a nominalist, if that isn’t obvious), and they don’t provide any evidence that the unique hues are anything other than artifacts of the human visual system.
What about phenomena such as flurescence? Fluerescent dyes are excited by specific spectra (equivalent to colours); if light is present, but at the wrong wavelengths, the phenomenon of fluorescence does not occur.
Or why not consider parts of the vertebrate visual system; different incoming wavelengths of light trigger different responses from different types of receptors; this happens before consciousness gets a look in.
So yes, colours, as in differences of wavelengths of electromagnetic radiation, exist in the real world. They don’t exist as colours, they exist as properties of the electromagnetic radiation, but the differences that we perceive as colours effect real physical differences in the way they interact with real physical matter.
Because it may accurately describe what is physically happening with the object, but it doesn’t describe in any way what we experience.
We don’t detect all of those wavelengths, and different animals and different people detect different things. For example, bees don’t detect red, but they do detect ultraviolet. There are some humans that are color blind, and none of us detect x-rays (unless you purchased those glasses in the back of comic books).
So by using that definition, we could have multiple objects we call “red” but they would have to be classified as wildly different colors due to the variation in all of the other wavelengths that we can’t detect.
It doesn’t work to say “ok then it’s the wavelengths humans can detect” because there is so much variability in humans.
If we said “ok then it’s the wavelengths a specific individual can detect,” then that supports the position that it is in our mind not in the object.
Ok, so color being the effect of light of certain wavelengths being reflected, of course a spectrum but certain areas of which humans have given generic names, in terms of a human’s ability to differentiate parts of that spectrum.
HOWEVER the fact that humans differentiate these effects and the fact that a varying set of wavelengths get reflected by objects are different issues. I’m sure there are non-subjective effects of the latter. Objects of the color we call black store more heat than those objects we call white, for example, because of this difference in light reflection. That’s an easy one, though. I wonder what less obvious effects there are?
But color IS the perception of EM reflectance. Are you asking. . . I think you’re defining yourself out of a question here. The human perception of “roughness” in touch has no transaction in itself in the same way-- the thing is rough-textured in itself in the same way that an object reflects a wavelength in itself. Maybe the difference between 'high pitched" and “low pitched” sound is analogous-- it’s descriptive of a way in which an object’s quality is perceived by us-- slightly different than the quality in itself, but the quality in itself is still there and has effects without us. All information we get via our senses is ‘coincidence’ with qualities.