You are mixing perception of a wavelength with the brain's image of that wavelength.
The CHEMISTRY in the eyes is fairly reliable and understood, so, we DO know what WAVELENGTHS we can see in what relative scale, etc. We DO know how the colors gradate across the spectrum, by wavelength, etc.
What we DON'T know, is whether 532 nm in MY BRAIN, looks to me the same way 532 nm looks to YOU in YOUR brain.
"Green" is a word we use to describe what 532 nm might appear as, but, the image in MY head might be what you'd call yellow...and so forth.
So we agree we all learned that the word for what we see as 532 nm is CALLED green, and, wavelengths similar to that wavelength might be different shades of green, and that leaves are green, etc.
Physically, it all works, as whatever color we "see" in our brain, is STILL that wavelength...and we all know to call THAT green.
There's no confusion.
We just don't have a way to look into YOUR head, and see what you see, when you say you see green.
:thinking: