Yoga, One of the six orthodox systems (darshans) of Indian philosophy, which has had widespread influence on many schools of Indian thought. It is better known through its practical aspect than its intellectual content, which is largely based on the philosophy of Samkhya. Holding that the evolution of the world occurred in stages, Yoga attempts to reverse this order so that a person reenters his or her state of purity and consciousness. Generally, the Yoga process involves eight stages, which may require several lifetimes to pass through. The first two stages are ethical preparations emphasizing morality, cleanliness, and devotion to God. The next two stages are physical preparations that condition the body to make it supple, flexible, and healthy; the physical aspects of Yoga have been most successfully popularized in the West. The fifth stage involves control of the mind and senses to withdraw from outward objects. The remaining three stages entail the cultivation of increasingly concentrated states of awareness, which will ultimately lead to release from the cycle of rebirth. See also chakra, kundalini.