Pre-existence, preexistence, beforelife, or premortal existence, is the belief that each individual human soul existed before mortal conception, and at some point before birth enters or is placed into the body. Concepts of pre-existence can encompass either the belief that the soul came into existence at some time prior to conception or the belief that the soul is eternal. Alternative positions are traducianism and creationism, which both hold that the individual human soul does not come into existence until conception. It is to be distinguished from preformation, which is about physical existence and applies to all living things.
Plato believed in the pre-existence of the soul, which tied in with his innatism. He thought that we are born with knowledge from a previous life that is subdued at birth and must be relearned. He saw all attainment of knowledge not as acquiring new information, but as remembering previously known information.
Baháʼí literature refers in a number of places to at least four key dimensions of pre-existence. Firstly, that the individual soul of a human being comes into being at the time of conception and only thereafter is eternal; in other words, it is not pre-existent. Secondly, in distinction to the above, that the souls of the world's greatest spiritual teachers, the founders of world religions, are pre-existent. Thirdly, that God, a reality which human consciousness can not comprehend, is pre-existent, that is he exists prior to time and to his creation. Fourthly, that the relationship between God and the phenomenal or contingent world is one of emanation, as the rays of the sun are to the earth. In other words, the pre-existent world of God remains separate from and does not descend into his creation.
In Buddhist cosmology, saṃsāra is the cycle of life and death. When a person dies in earth its human soul is born into the Naraka (underworld or the "purgatories" of the souls) and afterwards it is reborn on earth. Yama, a dharmapala (wrathful god), is said to judge the dead and preside over the Narakas and the cycle.