We all use them to pick out white and gold and blue and black things. We just differ on which things. — creativesoul

See what I said to Banno about the distinction between the adjective "red" and the noun "red":

The adjectives "red" and "painful" describe things like pens and stubbing one's toe.

The nouns "red" and "pain" refer to the mental percepts that pens and stubbing one's toe cause to occur. — Michael

Colours, as ordinarily understood in everyday life, are how things look, not how things reflect light. How things reflect light determines how things look, and so determines the colour seen, but reflecting light is distinct from colour.

When I think about the colour red I am not thinking about light reflectances; I am thinking about the visual percept.

Do all of the eyes that are perceiving the very same scenery at the very same time from nearly the same vantage point perceive the same light? Yup. — creativesoul

We see the same light but not the same colour. Therefore the light is not the colour. The light is the cause of the colour (much like the chemicals in the food are the cause of the taste), nothing more.

Carrying on from this, here are two different claims:

1. An object is red if it looks red
2. An object looks red because it is red

With the first, a sentence such as "the pen is red" just means "the pen looks red", and the word "red" in "the pen looks red" refers to the mental percept.

With the second, one must explain the "because it is red" part.

One offered explanation is dispositionalism, which gives us something like "the pen looks red because it is disposed to look red". But again, the "red" in "disposed to look red" refers to the mental percept.

Another offered explanation references wavelengths of light, which gives us something like "the pen looks red because it reflects 700nm light". Unlike previous examples, this is no longer a semantic claim, but an empirical claim, and in most cases it is true, but given variations in colour perception and so-called colour "illusions", a pen can look orange even though it reflects 700nm light, and so to reintroduce the terminology given in (2), a sentence such as "the pen looks orange even though it is red" is both meaningful and can be true. In this case, the word "orange" is referring to the mental percept and the word "red" is referring to the reflectance.

But also in this case, the use of the terms “because” and “even though” are questionable, as there’s nothing a priori wrong with these claims:

3. The pen looks red even though it reflects 700nm light
4. The pen looks orange because it reflects 700nm light

And so nothing a priori wrong with these claims:

5. The pen looks red even though it is red
6. The pen looks orange because it is red

Why focus on color specifically then? — Hanover

Because that's what this discussion is about. We're accepting realism in the general sense; atoms exist, reflecting wavelengths of light, and trees are a particular collection of atoms. We then want to know if colours are, as the naive realist believes, mind-independent properties of trees, or if they are mental percepts like pain.

As summarised by the SEP article quoted here, and as mentioned in the several scientific studies I've referenced, the physics and neuroscience is clear that colours are mental percepts, and I am going to trust what physics and neuroscience tell us about the world and perception (and certainly over a philosopher of language like Wittgenstein).

I'm just not buying into Lockean primary and secondary qualities where some qualities are deemed mind created and others inherent in the object. — Hanover

But you just did with pain? You accept that pain is a mental percept. Presumably you accept that trees are not a mental percept?

Or are you actually an antirealist/idealist, rejecting mind-independence entirely? Because that seems like a matter for a different discussion.

Not the same article, but this one is free to read:

Colour variation is the fact that what colour physical objects look to have depends on viewing conditions and a perceiver’s visual system. Both Colour Relationalists and Colour Eliminativists regard their analyses of colour variation as central to the justification for their respective views. Yet the analyses are decidedly different. Colour Relationalists assert that most instances of colour variation are veridical and infer from this that colours are relational properties of objects that are partly determined by perceivers. By contrast, Colour Eliminativists assert that colour variation is too unsystematic to ground the claim that many or most instances of colour variation are veridical. From this they infer that objects don’t have colours. I argue that the Eliminativist analysis is superior. On my view, the Relationalist account of veridical colour experience reduces to the assertion that objects have colour simply because they cause perceivers to have colour experiences of them. In this context, I argue, the resulting conception of veridicality is vacuous. More directly, the foundational idea of Eliminativism is the opposite claim: the fact that objects cause perceivers to have colour experiences of them is on its own not sufficient to justify or ground the claim that objects have colour. The Relationalist, I argue, has failed to justify anything stronger than this. In this debate we should thus side with the Eliminativist: objects do not possess colour; they merely cause us to undergo colour experiences.

And this quote may be of interest to @Banno and @Hanover:

It is fair to say that Eliminativists value adequate explanations of phenomena like colour variation more than, for example, offering a straightforward account of Common Sense Colour. In this regard, theirs is a “perception first” approach to colour (as opposed, e.g., to a “language first” or “no priority” approach). They need not (and generally do not) doubt that there are blueberries, that blueberries often cause perceivers to undergo colour experiences, or that our concept BLUE is often meaningfully applied, and to good effect, to blueberries. What they doubt is that blueberries are blue in a basic sense, believing instead that blueberries merely have the power to cause perceivers to undergo colour experiences. Insofar as we can explain what basic colours are, blueberries only have this causal role. No feature of blueberries is part of the basic nature of colour or of what constitutes basic colour.

Sure. The relevance of that distinction here, however, escapes me. — Banno

The adjectives "red" and "painful" describe things like pens and stubbing one's toe.

The nouns "red" and "pain" refer to the mental percepts that pens and stubbing one's toe cause to occur.

Pain and colour are different. I can hand you the pen, but not the pain. — Banno

You cannot hand me the pain or the colour.

Why should there be a singular thing to which the noun "colour" refers, and which must therefore be either in your head or in your hand? — Banno

You used the noun "colours" to say that colours are more than just mental percepts. This is equivocation, like using the noun “trees” to say that trees are both woody perennial plants and branching diagrams.

This is different to simply saying that the nouns “colours” and “trees” can refer to more than one thing, which I have repeatedly accepted.

But colours as ordinarily understood in everyday life are mental percepts, not reflectances, and trees as ordinarily understood in everyday life are plants, not diagrams.

It is obvious in context that the OP is not asking if atoms reflecting light is mind-independent.

Do you believe that pain is a mental percept or a mind-independent property of distal objects? If the former, does this lead to something like idealism? If not, why do you think that the claim that colours are also a mental percept leads to something like idealism?

I just don't understand your reasoning at all.

Some things, like pain, are in the head. Other things, like trees, are not. The science shows that colours, as ordinarily understood, are in the former group, not the latter. None of this entails abandoning realism entirely.

Yet it is more plausible to believe that it is the addition of a substance that causes the variation. There is no good reason to believe that the variation occurs without the added substance. — jkop

And adding cold water to boiling water means I no longer feel pain when I put my hand in the water. That doesn’t entail that pain is a mind-independent property of (boiling) water.

All you are explaining is what I already accept; that mind-independent properties are causally responsible for percepts, and so changing those properties will change which percepts are caused to occur - because the brain reacts differently to different stimuli.

For example, you claim that the colour variation in the dress is caused by the brain. — jkop

Because it is. I’ve already referenced actual scientific studies on the matter.

My colleague and I are looking at the same computer screen and the same light is striking our eyes. Yet we see different colours because our brains process the stimulus differently. This is a proven empirical fact.

A summary of what? The article contains many different sections and summaries, and you picked one that partly (debatable) suits one or two of your single-minded assertions. :roll: — jkop

I agree with the part I quoted, which is why I quoted it as being what I believe is correct. I don’t agree with the competing theories that I didn’t quote. I trust physics and neuroscience over armchair philosophy.

The “common-sense” naive view truly posits that colors are mind independent properties of objects because when I change the color of my room’s wall and get another bucket of paint with a different color, not a different mental percept. — Richard B

Some paint reflects 700nm light, which causes us to see red. Some paint reflects 450nm light, which causes us to see blue. Painting your room changes which wavelengths of light are reflected.

But colours as ordinarily understood are colours-as-we-experience-them, not micro-structural properties that reflect various wavelengths of light, and these colours-as-we-experience-them are mental percepts that various wavelengths of light cause to occur.

I intended this post above to be my final post, so I'll leave it there.

It is strange to ask if mental percept are mind-independent — Richard B

You're misunderstanding.

The Morning Star is a planet, but it is perfectly appropriate to ask if the Morning Star is a planet or a star (e.g. if one is unsure).

Our ordinary conception of colours is that of colours-as-we-experience-them, which contrasts with such things as colours-as-dispositions-to-reflect-light. The "common-sense" naive view falsely posits that colours-as-we-experience-them are mind-independent properties of trees and pens and chairs, but the science shows us that they are not; that they are mental percepts related to neural activity in the visual cortex.

Problem with this is you are no longer talking about mind dependent concepts but mind independent (brain neurons etc I would think you would call mind independent). — Richard B

If the mind is brain states then to say that something is mind-independent is to say that it is independent of brain states. Brain states are not independent of brain states.

So if colours are mental phenomena and if mental phenomena are brain states then colours are brain states. Brain states are not properties of trees and pens and chairs, and so colours are not properties of trees and pens and chairs.

I'll finish my time here by quoting the SEP article again. I believe this summary is correct:

One of the major problems with color has to do with fitting what we seem to know about colors into what science (not only physics but the science of color vision) tells us about physical bodies and their qualities. It is this problem that historically has led the major physicists who have thought about color, to hold the view that physical objects do not actually have the colors we ordinarily and naturally take objects to possess. Oceans and skies are not blue in the way that we naively think, nor are apples red (nor green). Colors of that kind, it is believed, have no place in the physical account of the world that has developed from the sixteenth century to this century.

Not only does the scientific mainstream tradition conflict with the common-sense understanding of color in this way, but as well, the scientific tradition contains a very counter-intuitive conception of color. There is, to illustrate, the celebrated remark by David Hume:

"Sounds, colors, heat and cold, according to modern philosophy are not qualities in objects, but perceptions in the mind. (Hume 1738: Bk III, part I, Sect. 1, [1911: 177]; Bk I, IV, IV, [1911: 216])"

Physicists who have subscribed to this doctrine include the luminaries: Galileo, Boyle, Descartes, Newton, Thomas Young, Maxwell and Hermann von Helmholtz. Maxwell, for example, wrote:

"It seems almost a truism to say that color is a sensation; and yet Young, by honestly recognizing this elementary truth, established the first consistent theory of color. (Maxwell 1871: 13 [1970: 75])"

This combination of eliminativism—the view that physical objects do not have colors, at least in a crucial sense—and subjectivism—the view that color is a subjective quality—is not merely of historical interest. It is held by many contemporary experts and authorities on color, e.g., Zeki 1983, Land 1983, and Kuehni 1997. Palmer, a leading psychologist and cognitive scientist, writes:

"People universally believe that objects look colored because they are colored, just as we experience them. The sky looks blue because it is blue, grass looks green because it is green, and blood looks red because it is red. As surprising as it may seem, these beliefs are fundamentally mistaken. Neither objects nor lights are actually “colored” in anything like the way we experience them. Rather, color is a psychological property of our visual experiences when we look at objects and lights, not a physical property of those objects or lights. The colors we see are based on physical properties of objects and lights that cause us to see them as colored, to be sure, but these physical properties are different in important ways from the colors we perceive. (Palmer 1999: 95)"

This quote, however, needs unpacking. Palmer is obviously challenging our ordinary common-sense beliefs about colors. Specifically, he is denying that objects and lights have colors in the sense of colors-as-we-experience-them (or colors as we see them), As far as this goes, it is compatible with objects and lights having colors in some other sense, e.g., colors, as defined for scientific purposes. Secondly, he is saying that color (i.e., color-as-we-experience it) is a psychological property, which in turn, might be interpreted in different ways.

I trust physicists and neuroscientists over Wittgenstein.

falsely claim that the reason we see different colours is to be found in the brain — jkop

It is.

What's your view of that? — frank

That it's wrong. The word "percepts" refers to percepts, the word "pain" refers to a subset of percepts, and the word "colour" refers to a different subset of percepts.

This Wittgensteinian approach that wants to explain all language in terms of some public behaviour just doesn't work, so move on from it. Some words refer to other things.

Well, as a nominalist I don't buy into universals. But the existence or non-existence of universals seems like matter for a separate discussion.

I don't understand what you're asking.

All I am saying is that colours as ordinarily understood are, like pain, mental percepts.

I don't deny that there are mind-independent objects with mind-independent properties that are the reliable and ordinary cause of such percepts. I just deny that these are what we ordinarily understand colours or pain to be.

The cause of the percept "transcends" the individual, sure. And we all agree that stubbing one's toe is painful. But pain is nonetheless a mental percept, not a mind-independent property of toes or the table leg.

You're saying that when I experience black, I'm experiencing an example of black. Everybody who has ever experienced seeing black has had their turn with this same thing: black percept. Right? It's something that transcends the individual? — frank

Ask the same question about pleasure and pain.

Do you deny that percepts exist when we dream? Do you deny that colours are properties of dreams? If you do not deny either then you must accept that colours-as-percepts exist when we dream.

Do you deny that percepts exist when we hallucinate? Do you deny that colours are properties of hallucinations? If you do not deny either then you must accept that colours-as-percepts exist when we hallucinate.

Do you deny that percepts exist when we having waking, "veridical" experiences? If you do not deny this, and if you do not deny any of the above, then you must accept that colours-as-percepts exist when we have waking, "veridical" experiences – even if you want to also talk about mind-independent colours-as-dispositions.

So at the very least you must accept that there are both colours-as-percepts and colours-as-dispositions. My only claim is that the former is our ordinary, everyday conception of colours, not the latter.

So to make this simple, here are two sets of claims:

Naive realism
1. Our ordinary conception of colours is that of sui generis, simple, intrinsic, qualitative, non-relational, non-reducible properties.
2. These sui generis properties are mind-independent.

Dispositionalism
3. Our ordinary conception of colours is that of micro-structural properties or reflectances.
4. These micro-structural properties are mind-independent.

I agree with (1) and (4) and disagree with (2) and (3).

I suspect that the overwhelming majority of people agree with (1), not (3) – even if the majority also believe (2), which the science shows to be false.

And if the overwhelming majority of people agree with (1), not (3), then (1) is true and (3) is false.

That leaves us with:

1. Our ordinary conception of colours is that of sui generis, simple, intrinsic, qualitative, non-relational, non-reducible properties.
5. These sui generis properties are mind-dependent
6. Therefore colours, as ordinarily understood, are mind-dependent.

None of this denies (4) or entails that we can't/don't use the adjective "red" to describe objects with certain micro-structural properties.

I perceive pain and pleasure. Pain and pleasure are mental percepts. I perceive smells and tastes. Smells and tastes are mental percepts. I perceive colours. Colours are mental percepts.

My ordinary conception of colours is that of "sui generis, simple, intrinsic, qualitative, non-relational, non-reducible properties ... not micro-structural properties or reflectances." This is how I am able to make sense of coloured dreams and hallucinations, synesthesia, variations in colour perception (some see white and gold, some see black and blue), and cortical visual prostheses; and it is these sui generis properties that I ordinarily talk about when I talk about colours.

Maybe you're different, but I suspect that the overwhelming majority of people are exactly like me (even if the majority do not recognise these sui generis properties to be mental percepts, naively believing them to be mind-independent properties of material surfaces).

But I have been at pains to point out that colour is not mind-independent; nor is it all in the mind. — Banno

It's unclear what you mean here. You seem to be using the singular noun "colour", which presumably refers to a singlular thing. So there's some singular thing that is in part mind-dependent and part mind-independent, as if half of it is in my head and half of it outside?

That certainly doesn't make much sense at all.

Perhaps what you mean to say is that the noun "colour" can be used to refer to (at least) two different things; one of those things is a mental percept and one of those things is something else? I've already agreed with this. My point is only that when we ordinarily think and talk about colours we are thinking and talking about the mental percept, not a surface layer of atoms that reflects certain wavelengths of light.

I don't think the OP, for example, is asking if atoms reflecting light is mind-independent. He's referring to the mental percept and asking if it's a mental percept or (as the naive colour primitivist believes) something mind-independent.

I've mentioned the implication that when you and I talk about something's being red, we would be talking about quite different things - you of your percept, and me of mine. — Banno

You are back to using the adjective "red". I am talking about the nouns "red" and "colour". Do you understand the distinction between an adjective and a noun?

But moreover, if "red" refers to something purely mental, how could you be sure that you are using the word correctly? How could you ensure that your use of "red" now matched your use of "red" previously? How could you be sure that your memory is not deceiving you, and what you are now calling "red" is what you previously called "green"? — Banno

Ask the same questions about the words "pain" and "pleasure". Regardless of what you or Wittgenstein think about language, pain and pleasure are mental percepts, not mind-independent properties of whatever objects or events cause pain and pleasure.

Ask also the same questions about the words "mind", "mental", "thought", "sensation", "belief", and so on.

You are seeing it wrong. — Lionino

If I am seeing the wrong colours then the colours I see are not mind-independent properties of the computer screen. So what are these colours I see? Percepts.

He doesn't conflate. He recognises, as I have been arguing, that colours as ordinarily understood and talked about are the appearances/percepts, not an object's disposition to reflect certain wavelengths of light. When I ordinarily think and talk about the color red I am thinking and talking about the former, not the latter.

The naive realist gets it even more wrong than the dispositionalist, thinking the appearance itself to be (or in some supposed veridical case “resemble”) a mind-independent property of material surfaces, often denying the existence of percepts entirely. Modern science shows this view to be wrong.

Fair enough, but that sound less like philosophy and more just basic neuroscience and physics. — Hanover

Yes, I mentioned that in an earlier post.

But what should be noted is that those who claim that colours are mind-independent clearly believe that there is a mind-independent world with mind-independent properties, and that sometimes experience is "veridicial", i.e. presents to us the mind-independent nature of the world. Such people should be scientific realists, and accept what physics and neuroscience tell us about the world and perception – and physics and neuroscience tell us that colours are percepts like pain, not mind-independent properties of pens.

To quote Bertrand Russell "naive realism leads to physics, and physics, if true, shows that naive realism is false".

Perhaps there's a place for idealism (which can reject science), but there's just no place for naive (colour) realism given our modern scientific understanding of the world.

I didn't enter this discussion to question scientific realism and argue for idealism or solipsism or nihilism. I am simply explaining what the science shows. I trust the science over armchair philosophy.

And someone who argues that colours are mind-independent properties of objects at least accepts scientific realism to some extent; they don't claim that the world is all mind-dependent.

Your argument seems to be that if I claim that colours are mind-dependent then to be consistent I must claim that everything is mind-dependent. This is nonsensical reasoning. You might as well argue that if I claim that pain is mind-dependent then to be consistent I must claim that everything is mind-dependent.

It is a fact that some things are mind-dependent and some things aren't. Smells, tastes, colours, and pain are mind-dependent and atoms, apples, chairs, and pens aren't.

This is what physics and neuroscience show, and I trust their findings. Unless and until the science shows otherwise, I commit to these theses.

I've already referenced actual scientific studies, so I'll now reference something a little more casual:

Your brain is lying to you — colour is all in your head, and other ‘colourful’ facts

We think of colour as being a fundamental property of objects in life: green trees, blue sky, red apples. But that’s not how it works.

“What colour is not is part of our world,” says neuroscientist Beau Lotto. “Every colour that people see is actually inside their head … and the stimulus of colour, of course, is light.”

As light pours down on us from the sun, or from a lightbulb in our home, objects and surfaces absorb some wavelengths of light and reflect others. “The ones that are reflected then land onto our retina,” says Lotto. There, those reflected wavelengths are transformed into electrical signals to be interpreted by our brain.

So we don’t really “see” colour, but reflected light, as interpreted in our brain. “It’s a useful perception of our world, but it’s not an accurate perception of our world,” says Lotto.

I don't really care much for the philosopher who responds with "nuh uh, 'cause Wittgenstein says..."

It talks about "different individuals view[ing] the same image ... reported it to be widely different colors" and "different individuals experienc[ing] different percepts when observing the same image of the dress".

Different percepts entail different reported colours because color nouns ordinarily refer to those percepts, not the light emitted by the computer screen.

It is a fact that I see white and gold and others see black and blue because it is a fact that I experience white and gold percepts and others experience black and blue percepts.

Ugh... the "some see white, others see black" is philosophical spaghetti. — frank

No, it's a scientific fact. There's a whole bunch of studies on the matter, such as Exploring the Determinants of Color Perception Using Thedress and Its Variants: The Role of Spatio-Chromatic Context, Chromatic Illumination, and Material–Light Interaction.

You seem to be letting some armchair philosophy (Wittgenstein?) get in the way of empirical evidence.

If you're going open the door to questioning inherent beliefs, then why arbitrarily limit it? — Hanover

It's not arbitrary. I've just read up on some physics and neuroscience of perception. Atoms are mind-independent objects with mind-independent properties; their electrons absorb and re-emit various wavelengths of light, this light stimulates the rods and cones in the eyes, the eyes send signals to the brain, the neurons in the visual cortex are activated, giving rise to visual percepts, including colour percepts.

Those who see a white and gold dress have different colour percepts to those who see a black and blue dress, because different neurons in the visual cortex are activated.

I don't understand the aversion to what I am saying. Do you object to me saying that pain is a mental percept, not a mind-independent property of fire?

The word "experiences" refers to experiences, so why can't the word "colours" refer to a subset of experiences?

And again, the use of the nouns "white", "gold", "black", and "blue" in the sentence "some see white and gold, others black and blue" when describing the photo of the dress is referring to differences in colour experiences, not differences in the computer screen's micro-structural properties or light emissions.

Do you agree or disagree?

If it's 1, then color language can refer to both subjective and objective accounts. — frank

I haven't denied this. I've only argued that our ordinary, everyday understanding of colours is an understanding of colour experiences, not an understanding of atoms absorbing and re-emitting various wavelengths of light, and that our ordinary, everyday use of colour nouns refers to these colour experiences.

The use of the nouns "white", "gold", "black", and "blue" in the sentence "some see white and gold, others black and blue" when describing the photo of the dress is the ordinary, everyday use and is referring to differences in colour experiences, not differences in the computer screen's micro-structural properties or reflectances.

We just happen to naively and unreflectingly think of these colour experiences as being mind-independent properties of distal objects rather than mental percepts. And we're welcome to think of and talk about the world in that way if we like (and we often do), but we'd be wrong.

That depends on what you mean by "know". If you mean certainty, then sure; we can't know what each person is experiencing. If you mean a true, justified belief, then we might know what each person is experiencing, e.g. if their experiences are in fact similar to our own. And again, given our similar biologies it stands to reason that our experiences are mostly similar.

I don't understand what you mean. Is there a "standard" pain? A "standard" pleasure? A "standard" sour taste?

He or she is saying that since this uncertainty exists, we have to conclude that color experiences are unique to each individual. — frank

We certainly have evidence that colour experiences can differ between individuals; the dress is the obvious example, but also differences in color categorization manifested by males and females.

And speaking for myself, my left eye sees a slightly different colour (or hue) than my right eye.

But given that the macroscopic world is deterministic, and given that we have mostly the same kind of eyes and brains, it stands to reason that our colour experiences are broadly similar in most cases.

Referring to the SEP article you referenced before:

There is a group of views about color, which come under one or all of the labels, Color Irrealism, Color Eliminativism, Color Fictionalism. These titles are a little misleading, since some theorists also talk of there being colors in the sense of being dispositions to cause experiences of a characteristic type, and/or being (attributes in/of) sensations. Following our earlier discussion, in section 1.2, we may take it that what the color-Eliminativist is denying is that material objects and lights have colors of a certain kind: colors that we ordinarily and unreflectingly take the bodies to have.

...

Color Primitivist Realism is the view that there are in nature colors, as ordinarily understood, i.e., colors are simple intrinsic, non-relational, non-reducible, qualitative properties. They are qualitative features of the sort that stand in the characteristic relations of similarity and difference that mark the colors; they are not micro-structural properties or reflectances, or anything of the sort.

Our ordinary conception of colours is that colours are "simple intrinsic, non-relational, non-reducible, qualitative properties ... not micro-structural properties or reflectances".

The naive (color primitivist) realist falsely believes that these colours are mind-independent properties of objects, when in fact they are mental percepts.

This does not deny that we can use the adjective "red" to describe objects with certain micro-structural properties or reflectances; it only states that micro-structural properties or reflectances are not how we ordinarily understand colours, and not what we ordinarily refer to when we use the nouns "red" and "colour".

'Red' refers to an object's disposition to cause certain colour experiences. — jkop

The word "red" can be used to refer to an object's disposition to cause certain colour experiences, but they ordinarily refer to those certain colour experiences. Those colour experiences are what we ordinarily understand by colours, especially before we have any understanding of an object having a surface layer of atoms that reflects certain wavelengths of light.

When I think about the colour red, I think about the colour experience, not atoms reflecting light. When we describe the fact that some see a white and gold dress and others a black and blue dress, we are describing differences in colour experiences, not differences in objects reflecting light.

The words "white and gold" and "blue and black" are referring to both, the light being emitted by the dress and perceived by the viewer. — creativesoul

They aren't referring to both. When my colleague and I look at the photo of the dress we see different colours. The noun "colours" isn't referring to the light because we don't see different light; it's referring to our visual percepts, which are different.

This is the ordinary use of the noun, and what we ordinarily understand colours to be (and what the naive realist mistakes to be a mind-independent property of things). That we then might use the adjective "coloured" to describe the computer screen does not change this. Much like the noun "pain" refers to the mental percept even though the adjective "painful" describes things like stubbing one's toe.

"Visual percepts" is again hollow. It means the patient discerned shapes. "Visual percepts" is hypostatisation. — Banno

"Visual percepts" is standard terminology in the neuroscience of perception.

See visual percepts evoked with an intracortical 96-channel microelectrode array inserted in human occipital cortex.

That sometimes one person sees blue where the other sees gold does not change this. — Banno

The nouns "blue" and "gold" in this sentence are referring to percepts. We see the same screen, we see the same light, but we don't see the same colours. Therefore the colours we see are not mind-independent properties of the screen or the light.

And the way the nouns "blue" and "gold" are being used in this sentence is the ordinary use of the word, and the things they refer to are what we ordinarily understand to be colours.

What he doesn't understand: you can't have a first premise (reality exists) and then from this premise prove that the premise is wrong. That's not a valid argument. — Gregory

Yes you can; it's called refutation by contradiction.