Nature, Brain, and Culture

Although many neuroscientists are trying to figure out how the brain works, Mark Changizi is bent on determining WHY it works that way.

The Colorful Smell of Richard Dawkins

Why is color the butt of all the "permuted qualia" jokes? Read More


What do you mean by "the qualitative feel of the colors we see" Mark? I assumed that to see color is also feeling it (sensed), given that the particular sensitivity of the eye is being stimulated by a particular light-speed that makes a particular color. When you use "qualitative" does this mean a measure of, say, the color red when compared with blue, therefore, adding an emotion to the observed and particular vibratory frequency that red is?

By the "qualitative feel of

By the "qualitative feel of red", say, one refers "what its like to experience red". When we see red, versus blue, and versus completely different modalities of perception, we experience it in a certain way. The question people like to ask is whether your experience of redness is that of mine -- are our "qualitative feels" the same?

Ah, so it is our (each

Ah, so it is our (each experiencer) difference emotionally? Each of our emotional attachment or non-attachment (or degrees thereof) to a color? To express this "qualitativeness" to another experiencer wouldn't one then need to use further allegory or poetic licence in order to "get across" this feeling? (I say "further" because even the noise "red" is allegorical of some vibration phenomena that falls under the "allegorical" label called "color").
Wouldn't it be more informative, for positive developement toward intimate human relations (being a psychology site), to consider the vibration phenomena we call "emotion" and, therefore, "cut to the chase" considering that color is on a more gross or superficial plane of experience than emotion (which you seem to be "getting at", anyway, with this "qualitative" thing)?

No, I didn't mean to suggest

No, I didn't mean to suggest it is just emotional. That's part of it, yes, and that's what I'm emphasizing in the piece. But the "qualitative feel" refers to the entirety of "what it's like" to experience redness. That includes that look of red, however one might want to phenomenologically characterize it. My point is that its entire "look" is due to how it sits within the entire perceptual network, including links to emotions, behaviors, and so on.

And I'd argue that, despite first appearances, color is not quite as superficial as we usually think. It's not just a label for the spectral reflectance of a surface in the world, but a much much richer kind of perception. ...about moods, emotions, behaviors...

Well you mentioned "3"

Well you mentioned "3" things,"..about moods, emotions, behaviors" but, really, they are one. Mood IS emotion and behaviour IS how we relate on an emotional level. I would further contend that ALL things are emotional, including all the colors of the rainbow. All colors merely reflect is the "mood" of human experience. Therefore, ALL human experience is (merely) a reflection of Reality. Just as an emotional feeling is a reflection of Feeling in it's entirety (feeling of "one with everything"). An emotion is a limitation on Feeling. Just as an "individual" color is a limitation on the Full spectrum of Light.


"What colors do is merely reflect the "mood" of human experience."
"All colors merely reflect is the "mood" of human experience"

Colorful Smells

I'm disappointed that your article didn't explore the objectivity/subjectivity of smell. I think smell is more objective than most people realize, except that we're not taught a good labling system as children so don't know how to talk about smell.

Yeah, practically no one

Yeah, practically no one knows how to talk about smell. I certainly have been scared away from ever doing research in it because there's so so many dimensions that a theorist is overwhelmed!

Can a smell be objective? I

Can a smell be objective? I thought us (the subject) are the ones that may choose to be objective about smell. Smell is an object, is it not?

The problem for a scientist

The problem for a scientist about olfaction is not that it is different than the other senses in regards to objectivity. The problem is simply that it is really really complicated! Vision, for example, can be understood as a visual field view of a 3D world, with distances perceived, and colors (themselves falling into a simple-ish three-dimensional color space), and so on. Complicated, but doable. But smell...there's potentially a thousand dimensions that our noses can smell, and there's no obvious way to even begin thinking about how to understand it. Olfaction, I am not worthy.

Smell is both a verb and a noun

Noun: "I smell smoke" (to perceive the odor or scent of through the nose by means of the olfactory nerves) Noun: "The smell of cut grass filled the air" (the quality of a thing that is or may be smelled)

"So there's actually a bridge

"So there's actually a bridge of neural tissues in these twins, which makes them quite unique." [...] "They share a lot of things normal conjoined twins don't," she said. "They have special abilities to see each other, see what each other's seeing through each other's eyes."

Color blindness

So how does color blindness fit in to this discussion, Mark?

Hi. Color blindness is

Hi. Color blindness is (almost always, and almost always just men) is when one has only two cones, more akin to what your typical mammal possesses. One has black-and-white, and yellow-and-blue dimensions. What one misses is the red-green dimension. And without the cone they "should" have, they mostly lose their ability to sense oxygenation modulations in the skin/blood. There's a long history of color blind doctors noting how handicapped they are at sensing the states of their patients, for example. What I'd *like* to look for is evidence that color blind people (again, mainly males) have a lower ability to sense emotions in others. No data on that yet.


Great article, Mark. One question: What do you make of synesthesia? Apparently (according to Wikipedia) it's common for synesthetes to identify "A" as with "red." Is there something about the universal perception of red that identifies with a (probably much less universal) perception of "A"?

I don't know about the

I don't know about the "A"-red case, but there's lots of grist to begin looking for such connections, and cross-modal ones as well. That is, on one way of viewing synesthesia, one says, "Gosh, these perceptual labels in one modality get linked for no reason whatsoever onto those perceptual labels in that other modality." But, instead, my bet is that the links come in regular patterns, due to the fact that they share similar fundamental meanings. Red, for example, can often indicate anger, and angry faces come with universal facial expressions, including an increase in the angularity of the expression (especially in the brows). One might expect that geometrical shapes found on angry faces will more commonly associate with the color of an angry face (namely, red). I talk a lot about cross-modal associations with audition in the upcoming book on music and speech, due out next year, btw.

Oh, I should have

Oh, I should have mentioned... In light of angry eyebrows, which are roughly "V" shaped, I wondered whether there was a historical propensity for visual symbols with a "V"-like shape to be associated with warning or danger. We examined several thousand symbols, and "V" shapes were much more likely to have a meaning along those lines compared to upside-down-V shapes, and both were more likely than alternative shapes.

Thanks for a great article,

Thanks for a great article, Dr. Changizi. Informative, and well written.

You make some great points about the evolution of color vision and how this relates to our perceptions. However, I am still a bit skeptical of the sameness of our qualia.

Here is my understanding of what you are saying: A qualia is completely determined by the evolutionary history of its attached color, by the emotions, functions and relations it is associated with. My first question - is this a correct understanding?

My second question - why should I be convinced that these are the only factors in determining qualia? It seems like you're defining qualia as the broad "sense" (in the way Frege used sense) of a stimulus. I don't think this is the standard view of qualia (or is it?). Most views of qualia encountered assume something more mysterious, hidden in the explanatory gap between brain and mind.

Final question - Even if a qualia is in fact determined fully by all these relations described, my personal experiences with a color will then slightly alter my qualia away from yours. While we share a vast evolutionary history, my emotions, my actions relating to the color will differ. This seems as if it will produce some differences in our qualia.

I'm sorry if my understanding of your article is completely off. If its not, I think your understanding of qualia is really fascinating. Rejecting causal mysteriousness is a very powerful idea. Have you written any more on this?

Final question first...

Final question first... People from different cultures will still tend to have their colors in roughly similar spots within their overall network, I'd claim, and to that extent they'd be experienced similarly. But I agree that, to the extent that peoples' networks aren't identical, their qualia won't be identical.

On the second question, my main aim of the piece was not to go at the problem directly, but indirectly. Qualia-rearrangement arguments are most compelling to people when applied to color, but not to most other aspects of perception. I'm arguing that these arguments, if they are worrying at all, are worrying to all aspects of our perception, not somehow especially to color (color being just as plugged-in to the rest of our network as the other stuff). Musical pitch and loudness don't seem interchangeable for obvious reasons -- their structures and how they link to the rest of our network aren't isomorphic. And I'd suggest that colors are not invertible for similar reasons.

More generally, I'm arguing that if you and I have very different networks, then our qualia will differ.

The harder part is the other way around, namely that if you and I have very similar networks, then our qualia will be similar. That's what I'm suggesting, but ultimately to actually "prove" this (which amounts to the "hard problem") in some appropriate philosophico-mathematico-computational sense is currently beyond me! (And although I have worked in philosophy before, e.g., on the riddle of induction, I've avoided getting into consciousness, mostly for the lack of any good idea on my part.)

I understand that you've

I understand that you've avoided getting into consciousness, but it seems to me that you have a good idea when you write: "qualia seem to be more than mere labels is that most of them have clear meanings and functions. We know what they're for, and how they plug in to the rest of our network of qualia". I believe that a solution to the hard problem of consciousness might be that the brain is a theater in which neural processes or functions become qualia when a network of meanings arises. Thus the color red, the smell of powder, the feeling of hotness, the sense of I, the sensation of pain, etc., all are conscious because they each have a function that becomes 'salient' for the organism's fate, and, as they play a part on the stage of the brain, they each convey a meaning which is a part of the narrative from which emerges a conscious experience.

Thanks. Cogitating. ...and

Thanks. Cogitating. ...and *may* even be motivated to begin pondering consciousness more seriously. (Always worried, though, that much of our intuitions about it are deeply incoherent.)

Thanks for the clarification,

Thanks for the clarification, Dr Changizi!

Different cultures..

Why do you think that people from different cultures have their colours in similar spots? I was wondering if people have their networks tweaked for maximum distinguishing capacity amongst their own race..

I think they do, indeed,

I think they do, indeed, something I talk a lot about in my book. But the tweak will be fairly small, as far as the entire color space is concerned.

Hmm, ok. Thanks for the

Hmm, ok. Thanks for the replies. I've added Vision Revolution to my "to-read" list.


I've come across articles where they talk about how different cultures have different distinguishing capacities for different colours based on the vocabulary they have. Does an illiterate & deaf/dumb person have less richness in his visual field?

Also, I've read about how synesthesia can be induced via hypnosis. When this is done, can any grapheme be linked to any colour? Can an unused colour be accessed this way?

The evidence suggests very

The evidence suggests very little dependency of color perception on language. E.g.,

As for hypnosis, I don't know about that. I'd guess that some graphemes are easier to link to some colors than others.

And as for "unused" colours, I'm not quite sure what you mean...

oh that was in reference to

oh that was in reference to color blind people and richard dawkin's sky-blue-pink

Ah. It would be neat if a

Ah. It would be neat if a red-green color-blind person could be "made" to imagine red by hearing the right kind of, say, auditory stimulus.


Why would it matter?
If the auditory stimulus generated a similar emotion to that of the visual stimulus that is "red-green", then is emotion not the important factor? There seems to be no need for the use of imagination in the way you imagine. Why should we imagine that our (shallow or superficial) experiences be the same? Is it not more to have deeper shared experiences (at that "emotional" level)?

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Mark Changizi is author of The Vision Revolution (Benbella), and Director of Human Cognition at 2AI Labs.


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