This paper responds to Justin Broackes’ reply to my paper, “On the retinal origins of the Hering primaries.” This paper aims to clarify and further develop the ideas presented in that article. I take up several of the points Broackes raises regarding the connection between my work and that of William Thornton (Journal of the Optical Society of America 61:1155–1163, 1971 ) and (Color Research and Application 24:139–156, 1999 ) on the “prime” and “anti-prime” colors of the human visual system, (...) the connection between those prime and anti-prime colors and hue category boundaries, and my attempt to link facts about low-level processing to the unique hues. Ultimately, while Broackes brings up several interesting issues and usefully illustrates the limits of my approach, I see no reason to retreat from the main claims I made about human spectral sensitivity and the hues. (shrink)