It&#x27;s not even an article I&#x27;d want to present to a high school class. An RGB pixel on your monitor is not emitting red, green and blue monochromatic (single wavelength) light. Same goes for the light reflected from a CYM pigment. Metamerism is at play, just like in the &quot;real world&quot;. The author confuses the need to choose three primaries with a requirement those primaries be monochromatic. And since when have painters stuck to three pigments?