Think four levels deeper. What color is the rainbow? Answer: all colors. What are all colors? Blue, Red, Yellow, Green and shades in between. Why is the rainbow all colors, blue, red, yellow, green, and shades? Because when light passes through certain media, color bearing rays of different frequencies change their trajectory, therefore separating from each other, causing the different colors to become visible and distinguishable.

Think four levels deep. Ask at least four questions for every significant assertion someone makes.