“Ludwig van Beethoven’s Ninth Symphony is arguably the most magnificent and complex single composition in Western music, and Beethoven wrote it after becoming totally deaf. He never heard the work performed. Synesthesia, which most individuals perform unconsciously, means a perception of one sense that stimulates another sense. In this case, Beethoven’s auditory sense was stimulated by his visual perception of the written score. In effect, he saw how it would sound. Most individuals can demonstrate synesthesia during hypnotic trance, but Beethoven did it consciously.”