The origins of Fantasy can be traced back to ancient mythology, which, as its basic purpose, explained the workings of nature. For example, there is the story of Prometheus, who felt pity for the mere mortals of earth and so he gifted them with fire. Zeus punished him by having him bound to Mount Causasus where for 30,000 years an eagle would swoop down on him daily and eat his liver. Another myth tells the story of the god Apollo who provided daylight by driving his chariot of fire across the sky every day. The supernatural quality of mythology would become one of the elements of fantasy.