Reincarnation, literally "to be made flesh again", is the belief that the soul, after death of the body, comes back to earth in another body. According to one belief, a new personality is developed during each life in the physical world, but the soul remains constant throughout the successive lives.
During recent decades, a significant number of people in the West have developed a belief in reincarnation. Feature films, such as Kundun, What Dreams May Come and Birth, contemporary books by authors such as Carol Bowman and Vicki Mackenzie, as well as popular songs, regularly mention reincarnation.
The scientific consensus, as expressed by the National Science Foundation, has identified and described ten subjects, including reincarnation, and they consider belief in those subjects to be pseudoscientific beliefs.
Eastern philosophical and religious beliefs regarding the existence or non-existence of an unchanging 'self' have a direct bearing on how reincarnation is viewed within a given tradition. There are large differences in philosophical beliefs regarding the nature of the soul (also known as the jiva or atman) amongst Eastern religions such as Hinduism and Jainism that do accept such an idea.[citation needed]
According to the scriptures, Siddhārtha Gautama taught a concept of rebirth that was distinct from that of any known contemporary Indian teacher. This concept was consistent with the common notion of a sequence of related lives stretching over a very long time, but was constrained by two core Buddhist concepts: anattā, that there is no irreducible ātman or "self" tying these lives together; and anicca, that all compounded things are subject to dissolution, including all the components of the human person and personality. At the death of one personality, a new one comes into being, much as the flame of a dying candle can serve to light the flame of another.
Buddhism suggests that samsara, the process of rebirth, occurs across five or six realms of existence. It is actually said in Tibetan Buddhism that it is very rare for a person to be reborn in the immediate next life as a human. This depends on the karmic potentialities (or "seeds") they have created with their actions and upon their state of mind at the time of death. If we die with a peaceful mind, this will stimulate a virtuous seed and we shall experience a fortunate rebirth; but if we die with a disturbed mind, in a state of anger, say, this will stimulate a non-virtuous seed and we shall experience an unfortunate rebirth. This is similar to the way in which nightmares are triggered by our being in an agitated state of mind just before falling asleep.
Skeptic Carl Sagan asked the Dalai Lama what would he do if a fundamental tenet of his religion (reincarnation) was definitively disproved by science. The Dalai Lama answered; "if science can disprove reincarnation, Tibetan Buddhism would abandon reincarnation... but it's going to be mighty hard to disprove reincarnation.