 What’s essential to chromatic phenomena, and what’s accidental? What might we safely dispense with? Rather than undertaking to identify, characterise and then sort through all of the folk notions of color, I shall say what it is that I have in mind when I think and talk about colors. Primarily, what I have in mind are red and yellow and green and blue, though I am also inclined to include white and black and gray as well, along, perhaps, with a special place for brown. (Hardin 1993: xx) 