True Believer

A True Believer is one for whom belief in something has gone beyond the evidence (if the evidence ever entered into it in the first place, which it often didn't) and moved to a religious or quasi-religious state where their views are perceived as absolute truth.

You find True Believers in all walks of life, but of course the most common sort are the canonical religious types like street corner evangelists. In a way I envy them their unshakeable faith - for me, doubt is a fact of life.

The biggest problem with True Believers is not their tenacity or their inability to acknowledge any evidence that contradicts their viewpoint, it's the fact that they are unable to distinguish between an atheist and an agnostic. Indeed, for them, the two are probably not distinct at all. Helmet zealots will freely accuse any helmet sceptic of being anti-helmet, because any failure to match their degree of zeal is, in their eyes, diluting the One True Message.

True-believer syndrome is a term coined 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. It has since been applied, more loosely, to refer to any belief without empirical or logical foundations.

Keene considered it to be a cognitive disorder, and regarded it as being a key factor in the success of many mediums. The term "true believer syndrome" is not used professionally by psychologists, psychiatrists, or medical professionals and is not recognised as a form of psychopathology or psychological impairment.

Raoul
In his book The Psychic Mafia, Keene tells of a psychic medium named Raoul. Some people 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."

Carlos
According to the Skeptic's Dictionary, an example of this syndrome is evidenced by an event in 1988, when James Randi, at the request of an Australian news program, coached stage performer José Alvarez to pretend he was channelling a 2000 year old spirit named "Carlos". Even after it was revealed to be a fictional character created by himself and Alvarez, 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."

419 scam
Article 419 frauds, also known as advance fee fraud, involve individuals inveigling others to give them their bank details, supposedly in order to make a large deposit, but actually in order to drain the account. Anti-419 activists refer to those who sometimes continue to believe in the good faith of the fraudsters as "true believers".