The illusory colors of black and white?

Actually, it seems all of your statements are incorrect. The white surface reflects only red light because only red light is incident, not because anything else is absorbed. There is no such thing as primary colors. A prism doesn't absorb or reflect, it refracts. There are many more than seven colors in the human visible spectrum. It's probably in the billions of monochromatic colors, and that's even before mixing. Note the difference between additive and subtractive color mixing. Shine RGB (red green and blue) lights onto a completely reflective screen and you get white. Place RGB filters in series and no light gets through (black). Black and white are 'colors' by customary definition.