Reincarnation:

Reincarnation is the belief that when one dies, one's body decomposes, but one is reborn in another body. It is the belief that one has lived before and will live again in another body after death. The bodies one passes in and out of need not be human. One may have been a Doberman in a past life, and one may be a mite or a carrot in a future life. Some tribes avoid eating certain animals because they believe that the souls of their ancestors dwell in those animals. A man could even become his own daughter by dying before she is born and then entering her body at birth.

The belief in past lives used to be mainly a belief in Eastern religions such as Hinduism and Buddhism, but now is a central tenet of such theories as dianetics and channeling. In those ancient Eastern religions, reincarnation was not considered a good thing, but a bad thing. To achieve the state of ultimate bliss (nirvana) is to escape from the wheel of rebirth. In most, if not all, ancient religions with a belief in reincarnation, the soul entering a body is seen as a metaphysical demotion, a sullying and impure rite of passage. In New Age religions, however, being born again seems to be a kind of perverse goal. Prepare yourself in this life for who or what you want to come back as in the next life. Belief in past lives also opens the door for New Age therapies such as past life regression therapy which seeks the causes of today's problems  in the experiences of previous lives.

L. Ron Hubbard, author of Dianetics and the founder of Scientology, introduced his own version of reincarnation into his new religion. According to Hubbard, past lives need auditing to get at the root of one's "troubles." He also claims that "Dianetics gave impetus to Bridey Murphy" and that some scientologists have been dogs and other animals in previous lives ("A Note on Past Lives" in The Rediscovery of the Human Soul).  According to Hubbard, "It has only been in Scientology that the mechanics of death have been thoroughly understood." What happens in death is this: the Thetan (spirit) finds itself without a body (which has died) and then it goes looking for a new body. Thetans "will hang around people. They will see a woman who is pregnant and follow her down the street." Then, the Thetan will slip into the newborn "usually...two or three minutes after the delivery of a child from the mother. A Thetan usually picks it up about the time the baby takes its first gasp." How Hubbard knows this is never revealed.

J.Z. Knight claims that in 1977 the spirit of a Cro-magnon warrior who once lived in Atlantis took over her body in order to pass on bits of wisdom he'd picked up over the centuries.  Ms. Knight seems to be carrying on the work of Jane Roberts and Robert Butts, who in 1972 hit the market with Seth Speaks. Knight, Roberts and Butts are all indebted to Edgar Cayce who claimed to be in touch with many of his past lives. One would think that channeling might muck things up a bit. After all, if various spirits from the past can enter any body at any time without destroying the present person, it is possible that when one remembers a past life it is actually someone else's life one is remembering.

From a philosophical point of view, reincarnation poses some interesting problems. What is it that is reincarnated? Presumably, it is the soul that is reincarnated, but what is the soul? A disembodied consciousness?

Reincarnation does seem to offer an explanation for some strange phenomena such as the ability of some people to regress to a past life under hypnosis. Also, we might explain child prodigies by claiming that unlike most cases of reincarnation where the soul has to more or less start from scratch, the child prodigy somehow gets a soul with great carryover from a previous life, giving it a decided advantage over the rest of us. Reincarnation could explain why bad things happen to good people and why good things happen to bad people: they are being rewarded or punished for actions in past lives (karma). One could explain déjà vu experiences by claiming that they are memories of past lives. Dreams could be interpreted as a kind of soul travel and soul memory. However, past life regression and déjà vu experiences are best explained as the recalling of events from this life, not some past life. Dreams and child prodigies are best explained in terms of brain structures and processes. And since bad things also happen to bad people and good things also happen to good people, one might well suppose that there is no rhyme or reason why anything happens to anybody.

Finally, since there is no way to tell the difference between a baby with a soul which will go to heaven or hell, and one with a soul which has been around before in other bodies, and one with no soul at all, it follows that the idea of a soul adds nothing to our concept of a human being. Applying Occam's razor, both the idea of reincarnation and the idea of an immortal soul which will go to heaven or hell are equally unnecessary.