A couple of years before he died my father reported to me that he'd consulted a doctor because he'd been encountering difficulty falling asleep at night. The doctor suggested that he try to fall asleep while listening to western classical music - a genre that Dad wasn't familiar with. A short while later he returned to the doctor and told him that the suggestion wasn't working. As he listened he discovered how interesting it was and instead of the music simply being in the background, lulling him to sleep, it kept him awake, wondering how it would continue to develop.