In the ancient India, philosophy has been traditionally divided into two main groups. These groups are called as the orthodox group and heretic group. The orthodox group believes in the authority of Vedas in all the philosophical matters. These orthodox systems are six in all. One of the most popular systems of philosophy is yoga.
It shares the following common beliefs with the other orthodox systems:
Belief in the permanent soul, which forms the basis of life.
Soul is supposed to discard one body at the time of death and enter a new one at the time of new birth.
A strong belief in the karma, which states that the events happening in a persons life are a direct results of the events in his previous life or lives (if the person has been born many times).
A belief that the life of an individual is primarily of misery and sorrow.
A belief in the state of complete freedom from misery and sorrow called mukti or moksha.
Yoga adopts the dualistic doctrine of explaining the universe of objects and living beings. It assumes that the universe was originally created by the uniting or samyoga of two eternal realities called purusha and prakriti. Purusha forms the basis of all the spiritual objects while prakriti deals with the material objects. Prakriti and everything that comes from it has three gunas viz.: sattva, rajo and tamas in various proportions and combinations.
Sattvaguna deals with all that is pure and holy while rajasguna deals with all the rich and royal qualities and tamasguna deals with all the baser qualities like greed, lust, anger, fear etc. The samyoga of the purusha and the prakriti is virtual. It does not exist but only the ignorant mind thinks it is real. This is due to the illusion called avidya and binds the purusha and causes him to transmigrate from one body to another in the various births. Once the avidya is dispelled completely, one can break free from the cycle of bith and death and can achieve moksha. This is easily achieved by following the eightfold path given by Patanjali in his Yogasutras.