Clear Body, Clear Mind is a pseudoscience book published in 1990 by the Church of Scientology's publishing house Bridge Publications. It is credited to L. Ron Hubbard who died four years earlier, and is largely a compilation of material he wrote in the 1960s. It is one of the canonical texts of Scientology and mainly deals with the Purification Rundown ("Purif"). Scientologists believe this "detoxification" program, created by Hubbard, has unique medical and spiritual benefits, but has been criticized by medical professionals as "dangerous", "quackery," and "in some cases lethal". Source: Wikipedia (en)