Think of a yes-or-no question. Hold it in your mind. Open the book.
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Rock Paper Scissors vs AIAn AI that learns your patterns You think of a yes-or-no question, hold it clearly in your mind, and open the book. Whatever page you land on is your answer. It will not be a plain yes or no. It will be a short phrase, something like "not yet" or "you already know" or "ask again tomorrow", and the work of interpreting it is yours.
The format goes back to Carol Bolt's book of the same name, and much further back than that to the bibliomancy tradition, where people opened a religious text at random and read the passage they landed on as guidance. Turning to a book for an answer to a question it cannot possibly know about is a very old human habit.
The phrases are deliberately ambiguous, and that is the mechanism rather than a flaw. An ambiguous answer forces you to supply the meaning, and what you supply comes from what you already think. If you get "not yet" and feel relief, you did not want to do it. If you get the same phrase and immediately start arguing with the book, you did.
Psychologists call the general tendency to read specific personal meaning into vague statements the Barnum effect, after the showman, and it is the reason horoscopes feel accurate. Here it is being used deliberately and in the open rather than to convince you of anything. The book is a mirror with a delay built in.
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You think of a yes-or-no question, hold it in your mind, and open the book. It returns a short ambiguous phrase rather than a plain answer, and you interpret it.
Carol Bolt's book of the same name popularised the modern version, but the practice descends from bibliomancy, in which people opened a text at random and read the passage they landed on as guidance.
No. The phrases are deliberately ambiguous, which forces you to supply the meaning from what you already think. That tendency to read personal significance into vague statements is known as the Barnum effect, and it is the same reason horoscopes feel accurate.
You can, but opening it repeatedly until you get the answer you want is itself informative. If you catch yourself doing that, you already know what you wanted.
A single clear yes-or-no question about whether to do something. Compound questions and requests for prediction produce answers you can bend to fit anything.
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