The Greek philosopher Pythagoras is frequently credited with originating the concept, which stemmed from his semi-mystical, semi-mathematical philosophy and its associated system of numerology of Pythagoreanism. At the time, the sun, moon, and planets were thought to revolve around Earth in their proper spheres. The spheres were thought to be related by the whole-number ratios of pure musical intervals, creating musical harmony.There is a legend that Pythagoras could hear the 'music of the spheres' enabling him to discover that consonant musical intervals can be expressed in simple ratios of small integers. Pythagoras told the Egyptian priests that Thoth had spoken to him and given him the ability to hear the harmony of the spheres. The tones correlated with the great celestial movements of the day. Pythagoras knew that only Egyptians of the 'right' bloodline, passing successful initiations, could enter the temples and learn the mysteries set in place by the gods at the beginning of time. To learn more he had to win their confidence and needed to appear as a royal soul, begat of the gods and above the sins of man. Pythagoras' concepts were transferred by Plato and others - into models about the structure of the universe. (Crystalinks)