Color Wheel CMY (Subtractive, Reflective or Absorptive)

Subtractive, Reflective, Absorbtive
In CMY/Subtractive black is a combination of all colors (light is completely absorbed).
In CMY/Subtractive white is an absence of all colors (light is completely reflected from a white substrate).
Actual light passing through glass filters, indicate this concept well.
Kindergarten Secrets: What Your Elementary Teachers Couldn't Tell You.
The primary colors are cyan, magenta and yellow... not red, blue and yellow.
Remember finger painting when yellow and blue make green? Cyan and yellow actually make green!
They are scientifically developed for ink, paint, crayons and anythng reflecting from paper or another substrate.