The hypothesis is immensely improbable, and the evidence can easily arise for other reasons. So the Bayesian calculation always comes down against the truth of the testimony, and in favour of the uniformity of nature. This is not to say that reports of things hitherto quite outside our experience have to be false. Science proceeds by finding such things. But we reason rightly when we maintain a sceptical attitude, until such time as the new phenomena are repeated and established, becoming part of the uniformities of nature.
