because the way you talk is as if the brain processes and adjusts, and then there is seeing of the result, as if there is a homunculus in there somewhere watching a screen. — unenlightened

I didn't mean to give that impression. What I am saying is that it's a mistake to think that a thing's colour is a property of the stimulus (in this case, the pixels on the screen), and also short-sighted (pun intended) to reduce the object of perception to that stimulus. If I see orange strawberries and you see red strawberries then we're seeing different things, even if a shared stimulus is responsible.

And when I see Johnny Depp swashbuckling on TV it would be a mistake to reduce the object of perception to those pixels on the screen.

I'm just reporting on what the neuroscientist said about it. He's the expert. — Michael

Sure. I didn't mean to say you had to be an expert and lay it out for me -- only that these are the questions I think people should ask when they hear or are tempted to say "the brain did it"

Anything I've read thus far, though I may be ignorant and am willing to read anything more, may involve more steps than that, but it comes down to a similar event. We'll follow the light to the cones where differentials generate potential energy which transfers up into the part of the brain associated with visual processing where. . . we find the black box again.

And it's not as simple as two colours "sitting next to each other" appearing as a different colour. Remember the dress? People saw different colours - some white and gold, others blue and black - even though the stimulus was the same. And that's because the stimulus isn't the only thing that's responsible for the perception of colour. Our bodies play an essential role in that dress being either white and gold or blue and black. — Michael

Couldn't the dress be both? It would just depend on how you look at it, no?

Like the vase/talking faces.


I think color blindness would be a stronger example for your case, because at least there is a demonstrated hereditary association. But I'd posit the same thing here -- only that we have to dig a little deeper into our bodies to "see as" the colorblind do, and currently lack the technology to do so.

It should be noted that seeing strawberries and seeing a picture of strawberries, is not the same thing. I'm near sighted, and wear glasses to see things far away. But when I'm shown a picture of things far away, I have to take off my glasses to see well, those objects in the picture. So clearly it is a distinct process by which you see a picture of an object from actually seeing that object.

It should be noted that seeing strawberries and seeing a picture of strawberries, is not the same thing. I'm near sighted, and wear glasses to see things far away. But when I'm shown a picture of things far away, I have to take off my glasses to see well, those objects in the picture. So clearly it is a distinct process by which you see a picture of an object from actually seeing that object. — Metaphysician Undercover

Having to repeatedly say "I see a picture of red strawberries" (and "I see a picture of a white and gold dress") is too cumbersome.

Couldn't the dress be both? It would just depend on how you look at it, no? — Moliere

The dress wasn't both, but definitively whichever it was, I forget now. The particular image was ambiguous, not the dress itself. One does not often mistake two faces for a vase, or one's wife for a hat.

Perhaps, but if we are discussing why we see blue strawberries as red, we might want to remind ourselves that we are not looking at strawberries, but a picture of strawberries.

Good point in saying it's the image, not the dress -- though it might be the case that the dress could appear this or that way in different environments, too.

I guess the question here would be -- while it is not often the case that we come across ambiguous images, why are there ambiguous images?

Michael seems to be stating that color, at least, is added by the brain, and the brain adds colors in different ways in different environments, so the same object can appear to be different colors.

I was attempting to say you could explain this with a part-whole distinction -- the dress does seem problematic to my tactic, so I was going for the "both/and", just depending on how you look at it.


But I guess it comes down to -- what do you make of ambiguous images? Is it simply that they are ambiguous, and there is nothing more to it than that?

I'm seeing some pixels on my screen that you have indirectly put there. But seeing pixels is seeing nothing.

With a bit of 'brain adjustment', I see what you mean. Sure, in the dark, the dress would look black, and wouldn't look like a dress. Seeing is brain adjustment, interpretation. We know there are no strawberries or dresses on our screens, as MU points out. We make an adjustment in seeing red strawberries in blue light as a way of making sense, so we know that seeing is active interpretation not passive registering of pixels. An ambiguous image has more than one sense to be made and thereby illuminates how we see, which is how we interpret. What makes no sense to me is that it should be misinterpreted as illuminating our inability to see. Once you get to the shop and look at the dress, or the strawberries, or the vase, you see what is there. Online shopping is a bit more hit and miss, like online philosophy.

What's the difference between red-tinted sunglasses and eyes? They both have a role in influencing what colour we see things to be. Just look at those with tetrachromacy. Do they see the "real" colours, or is the extra type of cone cell performing a "tinting" effect? — Michael

Whatever the answer to those questions, I know this much: if you reach Hanover's conclusion, then you've gone wrong somewhere along the line.

Whatever the answer to those questions, I know this much: if you reach Hanover's conclusion, then you've gone wrong somewhere along the line. — Sapientia

Or you haven't, and the naive understanding of colour is wrong.

if you reach Hanover's conclusion, then you've gone wrong somewhere along the line. — Sapientia

General guidance?

I'm at the tattoo parlour now.

But seeing pixels is seeing nothing. — unenlightened

What an odd thing thing to say. If so, then how did I just read that? I did so because I saw the pixels, and the pixels aren't nothing.

General guidance? — jamalrob

(Y)

You saw words made of pixels not pixels.

Or you haven't, and the naive understanding of colour is wrong. — Michael

Interesting that you've targeted what you call the "naïve understanding" of colour, rather than the ordinary way of speaking. What if my understanding of colour was just as sophisticated as yours, if not more so, but I objected to the wording of conclusions like Hanover's?

Interesting that you've targeted what you call the "naïve understanding" of colour, rather than the ordinary way of speaking. What if my understanding of colour was just as sophisticated as yours, if not more so, but I objected to the wording of conclusions like Hanover's? — Sapientia

Whatever the answer to this question, I know this much: if you disagree with me, then you've gone wrong somewhere along the line.

You saw words made of pixels not pixels. — Baden

No, I saw both. The words on the screen are the pixels.

I just see words. Anyway, what's a pixel if it's not part of a word, shape or colour? I'm not saying you can't speak of the situation coherently as you do. It's just not the only way of speaking about it. There's nothing odd in what un said.

Whatever the answer to those questions, I know this much: if you disagree with me, then you've gone wrong somewhere along the line. — Michael

Whether you're right or wrong can be put to the test. Do you think that to look red is to be red?

Whether you're right or wrong can be put to the test. Do you think that to look red is to be red? — Sapientia

Sure. Colour is an appearance, not a trans-appearance property of external stimuli.

Hmph. If I want to know the peak wavelength range of a particular colour, I'll ask the scientist not wearing the rose-tinted glasses.

Hmph. If I want to know the peak wavelength range of a particular colour, I'll ask the scientist not wearing the rose-tinted glasses. — Baden

What do you mean by peak wavelength range of a particular colour? Do you just mean the peak wavelength range that most people under normal light conditions (and when not wearing rose-tinted glasses) would see as a particular colour (e.g. red)?

In the vast majority of instances of perceiving colour, what is perceived is a combination of different wavelengths, not a single restricted range of wavelengths. The eyes have ways of dealing with those combinations. So speaking of a particular colour as a particular range of wavelength, is not very realistic.

I just see words. — Baden

How can you see the words if you can't see the pixels? You cannot. The words would not appear to you if not for the many tiny black pixels which form the shapes which we recognise as words. What you're saying is absurd. It's not analogous to, say, a cup and the atoms which compose the cup. I can actually see the pixels, and so can you.

Anyway, what's a pixel if it's not part of a word, shape or colour? — Baden

Let's say that it's the smallest visible component of an image, such as the images on your screen.

A pixel doesn't need to be part of a word. But I don't know how there could be a shapeless or colourless pixel. (The latter, if black, white and grey are a kind of colour, namely achromatic colour).

My device has 720 pixels of vertical resolution and 0.9 megapixels. Some of those pixels are the dark shapes which contrast with a white background - which is also pixels - and that's what I recognise as words.

I'm not saying you can't speak of the situation coherently as you do. It's just not the only way of speaking about it. There's nothing odd in what un said. — Baden

It's not the only way of speaking about it, but it is a sensible way of speaking about it, and what unenlightened said seemed odd - possibly false, and not the best way of wording it at all, in my assessment.

Sure. Colour is an appearance, not a trans-appearance property of external stimuli. — Michael

Colour is not just appearance, if it is appearance at all. Otherwise I couldn't appear red without being red, but I'm not red, and your red tinted glasses don't change that, they just change how I appear to you.

Colour is not just appearance, if it is appearance at all. Otherwise I couldn't appear red without being red, but I'm not red, and your red tinted glasses don't change that, they just change how I appear to you. — Sapientia

Sure it is. If you appear red then you're red. If you're red then you appear red. So you're red if I look at you through red-tinted glasses and not if I don't (presumably). What else would it mean to be red? Perhaps "have a surface that reflects light at a wavelength of ~620–740nm" or "appears red to most people with the naked eye in ordinary lighting conditions"?

And if colour is just an appearance, you can't claim that anything is red and really mean that, because "appears" and "is" don't mean the same thing.

How can you see the words if you can't see the pixels? You cannot. The words would not appear to you if not for the many tiny black pixels which form the shapes which we recognise as words. What you're saying is absurd. It's not analogous to to, say, a cup and the atoms which compose the cup. I can actually see the pixels, and so can you. — Sapientia

"How can you see the cup if you can't see the atoms? You cannot. The cup would not appear to you if not for the many tiny atoms which form the object which we recognise as a cup."

It's not absurd at all, it's a perfectly legitimate way of speaking.




It's pretty simple guys, red is either something there can be a fact of the matter about at some level or it is not. And there either exists a science of colour that is not nonsensical or there does not. If every human being in the world right now put on red tinted glasses that would not in the slightest change the scientific understanding or abrogate the scientific meaning of the term "red".

And if colour is just an appearance, you can't claim that anything is red and really mean that, because "appears" and "is" don't mean the same thing. — Sapientia

They do in this context. Or they don't, and the claim "the apple is red" is strictly speaking a fiction (even if it's an ordinary thing to say), as colour isn't a perception-independent property that external stimuli have.