True-believer syndrome

True-believer syndrome is an informal or rhetorical term used by M. Lamar Keene in his 1976 book The Psychic Mafia. Keene used the term to refer to people who continued to believe in a paranormal event or phenomenon even after it had been proven to have been staged. Keene considered it to be a cognitive disorder, and regarded it as being a key factor in the success of many psychic mediums.

The term "true believer" was used earlier by Eric Hoffer in his 1951 book The True Believer to describe the psychological roots of fanatical groups.

In his book The Psychic Mafia, Keene told of his partner, a psychic medium named "Raoul" in the book. Some in their congregation still believed that Raoul was genuine even after he openly admitted that he was a fake. Keene wrote "I knew how easy it was to make people believe a lie, but I didn't expect the same people, confronted with the lie, would choose it over the truth. ... No amount of logic can shatter a faith consciously based on a lie."

According to The Skeptic's Dictionary, an example of this syndrome is evidenced by an event in 1988 when stage magician James Randi, at the request of an Australian news program, coached stage performer José Alvarez to pretend he was channelling a two-thousand-year-old spirit named "Carlos". Even after it was revealed to be a fictional character created by Randi and Alvarez, many people continued to believe that "Carlos" was real. Randi commented: "no amount of evidence, no matter how good it is or how much there is of it, is ever going to convince the true believer to the contrary."

In the book When Prophecy Fails, Festinger and his colleagues observed a fringe group led by Marian Keech who believed that the world would be destroyed on December 21, 1954 and the true believers would be rescued by aliens on a spaceship to a fictional planet, Clarion. When nothing happened, the group believed that their devotion convinced God to spare the world and they became even more feverish in proselytizing their belief. This is one of the first cases that led Festinger to form the theory of cognitive dissonance.

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