Scientology is a body of religious beliefs and practices invented in May 1952 by American author L. Ron Hubbard (1911–86). Hubbard initially developed a program of ideas called Dianetics, which was distributed through the Dianetics Foundation.

The foundation soon entered bankruptcy, and Hubbard lost the rights to his seminal publication Dianetics: The Modern Science of Mental Health in 1952. He then recharacterized the subject as a religion and renamed it Scientology, retaining the terminology, doctrines, the E-meter, and the practice of auditing. Within a year, he regained the rights to Dianetics and retained both subjects under the umbrella of the Church of Scientology.

The Church of Scientology says that a human is an immortal, spiritual being (thetan) that is resident in a physical body. The thetan has had innumerable past lives and it is observed in advanced Scientology texts that lives preceding the thetan's arrival on Earth were lived in extraterrestrial cultures. Based on case studies at advanced levels, it is predicted that any Scientologist undergoing auditing will eventually come across and recount a common series of events.

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