There's an ancient Shinto koan (and nevermind that "Shinto koan" is a Googlewhack): "What are the colors of the cones?"  (Even before traffic cones, conical stalagmites sported white, red, orange, and black coloration from iron and other deposits.  Our colored traffic cones are like distant memories of our cave-dwelling ancestors.)  What the koan is getting at, of course, is that what we call colors are merely words; while lightwaves have objective properties, color is not one of them but rather is created subjectively by one's brain.