The million dollar challenge requires that the applicant has to beat 1 million to one odds. Setting such a high barrier for success makes sense if you are risking a one million dollar prize. However, 1 million to one odds are much higher than the scientific standard of proof so this challenge is not necessarily the best or fairest way to determine if paranormal abilities are genuine. Designing a test that is fair to both the applicant and the challenger requires sophisticated knowledge of statistics (How many trials would be needed for a psychic to have a 95% confidence level that they could beat million to one odds if their accuracy was 75%?) Most psychics don't have the understanding of statistics necessary to look out for their own interests and therefore most applicants will not be able to demand a protocol that gives them a fair chance of winning. This is the most likely reason no one has won the prize.
Furthermore, most applicants who know about Randi or understand the details of the challenge would be reluctant to spend the time, effort and expense of applying because they would not trust it to be a fair test or have confidence that they would be judged fairly or rewarded fairly if they succeeded.
Randi supposedly has said, "I always have an out. (Fate, October 1981)", and "I am a charlatan, a liar, a thief and a fake altogether." (This is reported to have been said on PM Magazine, on July 1st, 1982.) Applicants for the prize have legitimate reasons not to trust Randi. An interview in Will Stoor's book The Heretics quotes Randi in making several deceptive statements.
The prize is in bonds but Randi won't say when the bonds mature or who issued the bonds so no one knows what the prize really is. Why won't he say what the prize really is? Applicants are legitimately afraid the prize is some sort of worthless trick.
The applicant has to pay for their own travel expenses involved in attempting the prize. Why would they do that when they have good reasons not to trust Randi and they don't know what the prize really is?
Randi has a history of making mean spirited statements. He has been forced to retract statements in the past. However, applicants have to sign an agreement not to sue Randi even if he makes makes misleading, defamatory, slanderous, or libelous statements about the psychic.
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