Color blindness is diagnosed through a test devised by Japanese scientists sometime prior to 1964. The test consists of looking at cards with a series of dots in various colors. The dots form numbers and against a differently colored pattern of dots that forms the background. If you are color blind, you cannot see the dots. If you can see the dots, you're not. In the retina of the eye are cells that are referred to as rods and cones. One set of cells sees white and black, and works at night as well as day. The other set is responsible for color vision, and if I recall correctly is made up of cells with red, green, and blue sensitivity, much like old CRT displays. If the cells that are sensitive to one of the colors are missing or deficient, color-blindness results. Unless I'm mistaken the eye can detect as little as one photon of light. At least these are my recollections from my psych class back in 1964. "One god I can understand, but one wife? It is not generous.... It is not civilized." Sheik Ilderim, Ben-Hur, 1959 Thomas Hart tehart@xxxxxxx On Mar 16, 2012, at 5:04 PM, Julie Krueger wrote: > That very (red/green) thing is why I've never understood what exactly > color-blindness is and how it's identified/diagnosed. > > Julie Krueger > > > > > On Fri, Mar 16, 2012 at 3:13 PM, Walter C. Okshevsky <wokshevs@xxxxxx> wrote: > Yes, specifying the colours serves to focus the question more clearly. But my > epistemological conundrum remains. > > Imagine: What everybody calls and sees as "red," Walter sees as "green" but > calls it "red" because everybody else does. And what everybody calls and sees > "green" Walter sees and calls "red" because everybody else does. (Go figure, > Robert Brandom.) In this scenario, which is logically and empirically > possible, > there does not seem to be a way of detecting this visual and linguistic > discrepancy. But it remains an actual possibility. Perhaps something like > Quine's "gavagai" example? > > Hoping that Dan soon learns you your coulours, Walter > > P.S. Re Palin/Obama: She's probably thinking she can get Obama to roll his > eyes > upwards a sufficient number of times during the debate to win it. If it worked > for Al Gore vs George W, why not for her? > > > Quoting Julie Krueger <juliereneb@xxxxxxxxx>: > > > Sorry -- sent privately when I intended to send to the list. That seems to > > be the thing to do today. > > > > Julie Krueger > > > > Odd. Just today I had a conversational todo when I asked Dan if he liked > > the new blue sheets. He asked where they were. On the bed. The gray > > sheets?, he says. No, the blue sheets currently on the bed, says I. > > > > I understand there are lots of nuances of colors, hues, shades, tones, and > > other such vagaries out there. I should have said that I would be > > surprised if any child two years of age didn't know basic primary and > > secondary colors -- red, blue, yellow, green, orange, purple. > > > > On a totally unrelated note, Palin has challenged Obama to a debate.... I > > don't even know what to DO with that thought. > > > > Julie Krueger > > > > > > > > > > > > On Tue, Mar 13, 2012 at 8:45 PM, Walter C. Okshevsky <wokshevs@xxxxxx>wrote: > > > > > My wife insists that what I call "pale blue" is actually "grey." And she's > > > quite > > > amazed at how consistently I make that mistake. I'm equally amazed by the > > > fact > > > that what she sees as "grey" is actually "pale blue." Now I ask you, who > > > here > > > really "knows" their colours and who is mistaken? And don't forget that in > > > Montreal, drivers understand that "yellow" is "green but be quick about > > > it." > > > > > > Walter O > > > MUN > > > > > > > > > Quoting Julie Krueger <juliereneb@xxxxxxxxx>: > > > > > > > In my experience, children much, MUCH younger than 7 know their colors. > > > > I'm surprised if children who are two don't. > > > > > > > > Julie Krueger > > > > > > > > > > > > > > > > > > > > On Mon, Mar 12, 2012 at 8:27 PM, Andy <mimi.erva@xxxxxxxxx> wrote: > > > > > > > > > Why not? > > > > > > > > > > Andy > > > > > > > > > > > > > > > *From:* Julie Krueger <juliereneb@xxxxxxxxx> > > > > > *To:* lit-ideas@xxxxxxxxxxxxx > > > > > *Sent:* Monday, March 12, 2012 8:41 PM > > > > > *Subject:* [lit-ideas] Re: The Order of Aurality (ratification of > > > > > fiction?) > > > > > > > > > > Surely you didn't mean to say quite this? > > > > > > > > > > Julie Krueger > > > > > > > > > > > > > > > > > > > > > > > > > On Mon, Mar 12, 2012 at 5:41 PM, Andy <mimi.erva@xxxxxxxxx> wrote: > > > > > > > > > > I think abstract reasoning kicks in about at about age seven or so. > > > Does > > > > > a child that young even know colors? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > This electronic communication is governed by the terms and conditions at > > > > > http://www.mun.ca/cc/policies/electronic_communications_disclaimer_2011.php > > > > > > > > This electronic communication is governed by the terms and conditions at > http://www.mun.ca/cc/policies/electronic_communications_disclaimer_2011.php >