You remember, we said that the cause of color was the fact, that light which is made up of all colors penetrates every object in nature; that each object absorbs a certain quantity of the color and throws off the remainder. And that this remainder is what appears to our eyes as the color of the object. But while we think of this remainder as color, do not let us forget that it is light. And, recollecting that color is light, we can understand that one color has more or less light in it than another.