[js1138]

Here's a web site that attempts to show what it is like to have various kinds of color blindness. I think the examples are bad, and I think some of them are incorrectly labeled, but it's a start. Your friend with protonopia does not see everything as shades of grey. He just sees colors differently, and he will label some colors differently from you.

If color exists independently of the eye and brain, why will some people say that two color chips match exactly, and other people say they don't?

[MacDorcha]

No link.

Color does exist seperately. The problem is that "perception" is still playing it's hand.

A machine would identify them as different colors. But they still, in fact, exhibit color.

[Alamo-Girl]

Thank you for your reply and challenge!

If color exists independently of the eye and brain, why will some people say that two color chips match exactly, and other people say they don't?

The observer has nothing to do with the truth of the matter - whether the two color chips are identical or not.

Indeed, you may present the same color chip multiple times to a single observer and get mixed responses - when you as the investigator have prior knowledge that it is in fact the same color chip.