Bengtsson & Zyczkowski in the introduction (see p14-16) to their wonderful book make use of chromaticity diagrams to motivate their study of quantum states.
https://www.researchgate.net/profile/Karol-Zyczkowski/public...
>In a way tradition suggests that colour theory should be studied before quantum mechanics, because this is what Schroedinger was doing before inventing his wave equation.