Re: Colors

[Michael Porter <mbt@SYMPATICO.CA>]

On 1/3/02 1:48 PM, Jim Green wrote:

> Is there any data  which would indicate that when  a group of us look at
> the sky that we all have the same sensory experience?  Yes we all have
> agreed to call the sky "blue" but can it possibly be that when I see "blue"
> that I have the same sensory experience as when you see a fig leaf and you
> say "green" -- or a Camaro and say "red"?

This question _always_ comes up when I teach colour theory, and I have two
answers, both from personal experience.

One is that colour is a perception, created by our brains in response to
external stimuli. I personally don't think you can separate the basic
"that's blue" response from "that colour reminds me of a sunny day when I
was three, and my mother was telling me not to drop my blue toy boat into
the water because it was made of metal and would sink and we were on a ferry
and they probably wouldn't turn back for it" from "I like that colour" from
"Suddenly I'm thirsty." Not too scientific sounding, but these all may be
internal responses simply to seeing a particular shade of blue. I will
obviously have a different set of experiences than you. (Okay, the basic
shade will give some useful information like which kind of light is more
energetic, something my childhood memories wouldn't help with, so maybe some
of these perceptions are more useful to other people.)

The second thing I tell them is something along the lines of colour
blindness, but not as pronounced (I'm not colour-blind). When I close one
eye and look at the Caucasian newscaster (pink skin works best for this,
newscasters sit still long enough to compare the two views), the skin tone I
see is a little greener than if I use the other eye, which in comparison
gives a noticeably redder image. The effect is small, only noticeable if I
compare the two images back and forth. If I look at one colour (skin tone on
the TV), and my own two eyes (or eyes plus whatever brain pathways are
involved) can't agree, I doubt you and I are seeing exactly the same thing
either.

As for the big question of "Yeah but do I see red when you see blue," I
guess we'll have to wait for the first brain transplant to check that one
out! ;-)

Mike
--
Michael Porter
Colonel By Secondary School
Ottawa, Ontario, Canada