Reflections on color

What's with Red, Yellow, Green, Blue as the 4 colors of most game pieces?

Red, Yellow, and Blue are the three primary colors of paint. Primary meaning that all other colors are derived from these colors, and the three primary colors are not comprised of other colors.

Green, of course, is made of Yellow and Blue. However, Green is one of the primary colors of *light*. Perhaps you've heard of RGB? Red, Green, Blue? ... In light, Green is a primary color. LCD screens use red, green, and blue colors mixed in various intensities to make all the colors you see on a screen.

Are there secondary colors? Yes. Secondary colors of paint are Orange, Green, and Purple. These are obtained by mixing equal parts Red and Yellow, Blue and Yellow, and Red and Blue, respectively.

Have you heard of CMYK? That's Cyan, Magenta, Yellow, and Black. While these are ink/paint colors, the colors themselves are secondary colors of light: equal intensities of Green and Blue, Blue and Red, and Green and Red, respectively for the colors.

What is interesting is that Cyan is "kinda" blue, Magenta is "kinda" red, and Yellow is ... yellow, hence we get to mixing "light" colors to make "pigment".