Lol, well, white light is every color of light in the spectrum combined. That's why you get a rainbow when you flash a beam of light into a prizm, or into the hose when you're playing with the water. Because the light is bent by the shape of the glass, or the beads of water being sprayed, and each color has it's own wavelength, you are able to see the rainbow.
Now as far as pigments go... we all know that if we melt all our crans togeather that we get this mud looking brick right?