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Extraordinary claims who said that?

  1. Jul 6, 2010 #1


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    "Extraordinary claims..." who said that?

    "Extraordinary claims require extraordinary evidence."

    Obviously, Carl popularized it, but is he the one who coined it?

    I just read in my book "Escape from Hell"*, that it was Descartes who first said this. True?

    *(Carl is in Dante's Eighth Circle of Hell (along with Diviners and Fortune Tellers) for being a false prophet. He started teaching science but then it got way from him and he started making predictions about Earth's demise in a Great Ice Age).
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  3. Jul 6, 2010 #2

    D H

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    Re: "Extraordinary claims..." who said that?

    Laplace: “The weight of evidence for an extraordinary claim must be proportioned to its strangeness.”
  4. Jul 6, 2010 #3
    Re: "Extraordinary claims..." who said that?

    To the best of my knowledge, it was Marcello Truzzi. Founder of CSICOP, left on a bad note and coined the term "pseudo-skepticism". He definitely said it before Sagan.

    So I guess it wasn't Truzzi.
  5. Jul 6, 2010 #4
    Re: "Extraordinary claims..." who said that?

    If you consider Dirac's equation of his "sea", his own reluctance to accept the theory until positrons were more than definitely detected would be a fine example of this in real science. In a time when theory is the forerunner of experimentation (often), this is even more critical than at any time in history.
  6. Jul 6, 2010 #5


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    Re: "Extraordinary claims..." who said that?

    David Hume at least had a variation of it when he wrote about his skepticism towards the possibility of divine miracles.
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