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Scientology is a set of books, ideas, lectures, and other materials devised by L. Ron Hubbard, with its origins in the self-help system "Dianetics". Scientology espouses the principle that most of the major psychological, social, and physical ailments of society are caused by thetans. Thetans are stated to be the invisible souls of alien spirits which attached to mankind in ancient times. These spirits had been released when the alien Emperor Xenu  kidnapped them, flew them to earth, placed them around the feet of volcanoes, and then detonated them. These alien spirits then floated up toward the sky, where Xenu had built devices to capture them in clumps. The souls were deposited in a facility, where they were forced to watch a giant television screen, which brainwashed them.
Scientology's official documents, and L. Ron Hubbard's lectures have stated that Dianetics and Scientology are based upon hard science. Among the facts espoused as hard science are: that the above-mentioned alien souls have traumatic memories which cause all of mankind's true problems, and that no psychiatrist exists anywhere who is not in some way criminal and looking to harm their patients.
Detail beliefs in full without running on, add references for -everything-, especially controversial bits, and make it truthful
As mentioned above, the primary belief espoused in Scientology is that thetans, the brainwashed souls of aliens killed by Emperor Xenu, have affixed to mankind and done it harm. They believe that the traumatic events surrounding the death and brainwashing of the alien souls has caused harmful "engrams" in the humans these souls attached to. P
"A thetan who is completely rehabilitated and can do everything a thetan should do, such as move MEST and control others from a distance, or create his own universe; a person who is able to create his own universe or, living in the MEST universe is able to create illusions perceivable by others at will, to handle mest universe objects without mechanical means and to have and feel no need of bodies or even the MEST universe to keep himself and his friends interested in existence".  add other references to superhuman clears
Organizations, Practices, and Affiliates
The details given above, which include the story of "Xenu", are just a small part Ref to youth human rights international, Sea Org, costs they charge, etc. Mention fair game and suppressive persons.
A fair amount of controversy has arisen surrounding the way in which Scientologists recruit members of their doctrine. Refs to Fishman and Personality Tests, as well as practices regarding children, Lisa MacPherson, legal challenges, death of jeremy perkins, Tom Cruise's remarks, German "cult" designation, and loss of largest libel suit in Canadian history, add "Versus the internet" for a few sentences, including attacks on owner of YTMND.com for postings
Scientific and Social Criticisms
Ref to come to Clambake's critique of OT 3, add info about critics and their actions to discredit critics Add refs to anti-psychiatry beliefs, belief that it is hard science, and basic refutations of same
- OT III: The details of the Xenu story, and an overview.
- Hubbard, Scientology 8-8008, pg 114 (1st ed), pg. 151 (1990 ed.)