[DonaldFisk]

> After time the color filter will start to associate various concepts and feelings add images with various colors. This association is what starts making the colors themselves have meaning even if they can't see the colors the same way that you and I can.

The filters are just pieces of transparent coloured plastic. How are they capable of forming associations?

Also, associations on their own (e.g. blue with sky, red with blood, green with grass) don't give you any idea what colours are like. Knut Nordby (and many other people with achromatopsia) knew these associations as well as you or I know them, but made it quite clear that he had no idea what it was like to see in colour.