Dear Friedrich --

Colors -- tons of them, an infinitely divisible spectrum. Don't even computers these days display something like 16 million of them? Yet the names of colors are so few ... Let's see: red, green, blue, yellow ... Er. Violet. Orange. Pink. Purple. Tangerine. ... And some of those colors that seem to mean something to chicks if not to most dudes: fuchsia, aqua, heliotrope, chartreuse.

Why do we break down the spectrum in the limited way we do? We bundle all these colors and put the label "red" on them. We bundle all those colors and put the label "purple" on them. Why don't we slice and dice the spectrum in an entirely different way?

Biology is apparently the answer, though don't ask me for specifics. It turns out that all -- or nearly all -- cultures slice and dice the spectrum in pretty much the same way: red, blue, green, yellow, etc. Our wiring is simply such that red, blue, green, yellow, etc, stand out; they speak to us and we recognize them. In between? I dunno, it's kinda muddy ... I've heard of a culture or two that don't recognize this or that color. But apparently these exceptions and deviations are rare.

The lesson: there is no color perception without interpretation. To perceive is to interpret -- no one sees a color for what it really is. (Which of course is simply waves.)

Anyway, I've just run across a study that reports that not only is the way we break down colors biologically based, so is the way we visually experience distance. Duke University Medical Center neurobiologists have run experiments, and the results support the theory that "the visual system has evolved to make the best statistical guess about distances and other features of visual scenes, based on past experience."

In other words, we aren't general-purpose computers gathering an infinite amount of data and then sifting and sorting our way to the truth through an infinite number of possible interpretations. Instead, we're made up of special-purpose modules that zero in on what pertains, more or less, to our survival. Judging distances, like judging colors, isn't a logical process -- it's a series of statistically-based best-guesses. You riffle through a limited number of possibilities until you hit on the one that feels right. There are interpretive biases built into the very biology that is us. Cool! Though, really, who'd have expected otherwise?

Here's a quote from one of the researchers, Dr. Dale Purves:

You see distances in this way because reflected light from points in space that project onto your retina is completely ambiguous with respect to how far away that point really is. The observer nonetheless has to solve the problem of what's out there. The visual system has evidently evolved to use the statistics of past experience to 'understand' what those distances are most likely to be, and that is what you see.

Here's a description of the study.

Best,

Michael

Nifty. Yet, I have always wondered if the blue I see is the same as the blue you see. What if my blue is entirely different from your blue, but I've just been taught to call it the same thing that you have? 10 year olds and I find this questions fascinating...;)

Posted by: Courtney on October 23, 2003 6:25 PM

Interesting post. For another discussion of color and consciousness, you can check out a post I did based on Vilayanur S. Ramachandran and William Hirstein's essay, “The Three Laws of Qualia: What Neurology Tells Us about the Biological Functions of Consciousness, Qualia and the Self”. You can read this here. The "Three Laws of Qualia" also maintains that quales such as colors (and other sensory categories) are the result of choices--in Ramachandran's language, they are "irrevocable"--and suggests that they represent an intermediate stage of brain processing between raw input and executive (i.e., "conscious") decision making, which would explain why it was useful to weed down the limitless colors of the world into a much smaller number of "significant" colors needed to make decisions.

Posted by: Friedrich von Blowhard on October 24, 2003 10:58 AM

I wonder if Ramachandran and Humphrey know each other, and what they think of each other's work. They certainly seem to be thinking along similar lines.

What strikes me about some of what they suggest is the implication that "bias" or "interpretation" doesn't just happen to be built into the system -- it's part and parcel of the system. It's not a tacked on thing that can be done without, it's of the very nature of being who and what we are. There is no "seeing" in the human sense without a bias towards blue/red/yellow (let alone a bias towards the slice of the spectrum that our eyes register).

It seems to me that one of the modernist delusions is that such bias is wrong and perhaps even evil, and that there's some way of getting beyond or past it, usually by suppressing it (or by projecting a "genius" that can transcend it). Do you think that's fair? If so, it has always struck me as half-understandable, half-idiotic. There is a "something more" (it seems to me) that we all sense, something beyond what's provable and completely empirical -- that feeling I do understand. But as to the question of how to access or get to or experience it, that's where I find the modernist thing deluded. They seem to think that such an experience can be willed, or genius-ified, or achieved by crushing what they feel gets in the way (our built-in biases, for one thing). Maybe I'm just lazy, but it has always seemed wiser to me to accept the built-in givens of being, to work with them -- and to be open, as best you can, to whatever experiences of (ahem) the divine that might come your way. Of course, this demands modesty, openness, and an acceptance of the idea that perhaps the divinity can't be bossed around. I have no trouble seeing these as virtues to be cultivated, and find myself wondering why the modernists would. The only answer I come up with is that they're diehard romantics and hold-your-breath-till-you-turn-blue eternal adolescents, more determined to protest what it is to be alive than open to the experience of what it is to be alive. I'm grateful for bits and pieces of this and that. For them, it always seems to be a matter of all or nothing. Which has me thinking of swing-for-the-stands Herbert Muschamp, as well as that good Bellocchio movie ...

Posted by: Michael Blowhard on October 24, 2003 11:55 AM

I'm sure that back in college I read about studies showing that there are cultures unconnected to mainstream society that don't divide up the spectrum the same way we do. For some reason I particularly remember that the line between blue and green varied hugely.

This was twenty years ago so I can't give citations, unfortunately.

It doesn't seem evil to me to accept that most of us have some common biases, whether hardwired into us or because of our shared cultural assumptions. What seems evil to me is turning those biases into a reason to pound on people who draw the line between blue and green in a different place than they do.

No point getting orange in the face over the many mauve areas in life, it seems to me.

Posted by: Scott on October 24, 2003 1:17 PM

Michael:

Maybe I'm off the track, but I suddenly flashed on Kant's "Critique of Pure Reason" in reading your comment:

It seems to me that one of the modernist delusions is that such bias is wrong and perhaps even evil, and that there's some way of getting beyond or past it, usually by suppressing it (or by projecting a "genius" that can transcend it).

Doesn't the Modernist/Leftist war on the notion of "nature" and "limits" remind you of the tussle between Kant and various later schools of philosophy about the limits of what is knowable? Did we spend the 20th century in arts and culture fighting the same battles as philosophy fought in the 19th century? Anybody out there who knows more philosophy than I (which has got to be most people) willing to comment on this?

It would be interesting to take a class, if one is offered, on the philosophical roots of "cultural movements," modernism included.

Posted by: Friedrich von Blowhard on October 24, 2003 2:43 PM

Remember the Krebs cycle? Biology, mitochondria, energy conversion? Remember how it all boils down to that electron bopping about? That electron is essentially electricity (yes, the Matrix is right, we are big batteries)....so it makes sense to me that if most living things use the Krebs cycle (and I'm fairly sure that they do), and that if electricity can be viewed (electron microscope, etc)...then the notion of auras makes sense. Why shouldn't there be a mutation in the genetic code that allows someone to see a wee bit further into the spectrum than others?...Just a random thought I've had ever since AP Biology...

Posted by: Courtney on October 25, 2003 9:31 PM

Wow! Thanks! Qualia is my new research topic! *hugs*

Posted by: Courtney on October 25, 2003 9:33 PM

It's definitely true that not all cultures define the same set of colors. There's a sequence anthropologists have discovered. The simplest cultures recognize only black and white. Then black, white, and red. Then black/white/red/blue or green, black/white/red/blue and green, and so on. (My example may be garbled.) The stages are quite definite: no culture has "brown" before "yellow" (again, the example may be garbled).

Also - on the statistical rather than logical nature of distance estimation: Stephen Pinker has written about how many of our thought processes are approximators rather than logical analyzers. This explains the appeal of gambling systems: they are designed to spoof the approximators, which tell the mark "this is profitable", even though logical analysis proves it isn't.

Posted by: Rich Rostrom on October 27, 2003 2:09 PM






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