I'd mention the book Blue and Yellow don't make Green, which taught me that my minimum set of paints should be:

* A purple-inclined red (crimson) and an orange-inclined red (scarlet)

* A green-inclined yellow (practically speaking, "spring green") and an orange-inclined yellow ("yellow")

* A purple-inclined blue (ultramarine) and a green-inclined blue (cerulean)

* White to make light tones (don't worry about black)

And these let me get almost all the spectral colors because, I think, the pigment grains don't interfere and don't cause subtractive mixing (there was some sketchy explanation about light bouncing between different pigment particles before bouncing properly back from the canvas). There are gaps due to the lack of any pure primary color, which we basically give up on being able to buy.