Do you remember the old question: If a tree falls in a forest, does it make a sound if no one is present? I was reading a book by Newberg and Waldman entitled Why We Believe What We Believe, and came across a couple interesting comments. Music is a neural interpretation of sound. Color is a neural interpretation of light—and to the brain color is primarily a subjective experience. There is no neural receptor that distinguishes any gradation of gray. It, like many other colors the human brain imagines, is a belief construction within the brain—a form of understanding. A thought. This leads to the supposition that no two brains ever hear or see anything in identically the same way.