If I recall correctly, the US Air Force’s Project Blue Book, on UFOs, explained away as a sighting of the planet Venus what turned out to actually be an experimental aircraft. No, I don’t believe in UFOs either; but if you’re going to explain away experimental aircraft as Venus, then nothing else you say provides further Bayesian evidence against UFOs either. You are merely an undiscriminating skeptic. I don’t believe in UFOs, but in order to credit Project Blue Book with additional help in establishing this, I would have to believe that if there were UFOs then Project Blue Book would have turned in a different report.
This is wrong. Explaining away a single experimental aircraft as Venus doesn’t mean that you’re an undiscriminating skeptic or that whether there are UFOs doesn’t make any difference to what you would say. It just means that you’ve made one mistake. And estimates based on probability are going to turn out to be wrong sometimes; there could very well be one that is an aircraft but where the available information indicates that Venus is more likely than an aircraft. Someone using this available information would legitimately (although incorrectly) deduce that the object is Venus.
Responding to an old post:
This is wrong. Explaining away a single experimental aircraft as Venus doesn’t mean that you’re an undiscriminating skeptic or that whether there are UFOs doesn’t make any difference to what you would say. It just means that you’ve made one mistake. And estimates based on probability are going to turn out to be wrong sometimes; there could very well be one that is an aircraft but where the available information indicates that Venus is more likely than an aircraft. Someone using this available information would legitimately (although incorrectly) deduce that the object is Venus.