Why don’t color scientists list black and white as colors? Fire engines used to be red. Yellow-green is now the preferred color. Why the change? What color does red cloth appear to be when illuminated...

Why don’t color scientists list black and white as colors? Fire engines used to be red. Yellow-green is now the preferred color. Why the change? What color does red cloth appear to be when illuminated by sunlight? By light from a red neon sign? By cyan light?