Reincarnation (samsara)

Hindus and Jains affirm samsara, the beginningless cycle of birth, death, and rebirth through which a being passes according to its karma. The Upanishads articulate the doctrine that the self (atman) is not extinguished at death but takes up a new embodiment shaped by past action, and the Bhagavad Gita likens the changing of bodies to the changing of worn-out clothes. Jainism holds a parallel view in which the eternal soul (jiva), weighed down by karmic matter, transmigrates through countless forms, plant, animal, human, and various classes of heavenly and infernal beings, until purified.

Historians of Indian religion debate where the doctrine itself came from. It is largely absent from the earliest Vedic hymns, which focus on this-worldly blessing and an afterlife in the world of the fathers, and appears fully formed only in the later Upanishads; some scholars, Patrick Olivelle among them, have argued the transmigration doctrine may reflect currents from outside the mainstream Vedic sacrificial tradition, possibly from ascetic or sramana milieus later absorbed into orthodox Hindu thought, while others hold it developed organically from within Vedic speculation about the fate of the ritual self after death. Both traditions elaborate samsara into structured cosmologies of multiple realms of rebirth, heavens, hells, and various non-human states, through which the transmigrating self or soul may pass depending on its accumulated karma.

Samsara defines the predicament that the Indian traditions seek to escape: unending wandering through lives marked by suffering and impermanence. It is inseparable from karma, which governs the direction of rebirth, and from the goal of release, moksha in Hinduism, liberation of the purified soul in Jainism, nirvana in Buddhism. The traditions differ sharply over what, if anything, transmigrates: Hinduism and Jainism affirm an enduring self or soul that persists through the cycle, while Buddhism denies any permanent self and describes rebirth as a causal continuity, a stream of conditioned states, without positing anything that literally passes from one life to the next, a position later Buddhist philosophy pressed to its limit by arguing that samsara and nirvana are, from the standpoint of ultimate truth, not two separate realities at all.

The shared picture nonetheless unites the traditions in treating ordinary existence as something to be seen through rather than simply lived, a stance that separates them from religious outlooks in which a single earthly life, followed by a final judgment, is the whole of the story. Comparative theologians sometimes note that samsara's very structure, an impersonal law working itself out across countless lives without requiring a judging deity, gives these traditions an account of justice and consequence that does not depend on divine intervention in each individual case, even where a creator or supreme being is also affirmed.