No testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous than the fact which it endeavors to establish.
I love the above quote from David Hume. It sums up so much of the fundamental nature of skepticism.
It seems obviously true when phrased so elegantly, but many people still don’t seem to have adopted it as a functioning heuristic. We’re often widely expected to believe that, for instance, aliens from other worlds are visiting our own, on the basis of no further evidence than that somebody says they saw something.
Or, that a dead Jewish guy came back to life two thousand years ago, because there’s a book about some people who claimed to have met him.
It seems there are two main ways that people counter Hume’s principle, to support whichever unlikely and unsubstantiated claim takes their particular fancy.
Firstly, it’s often implied that the falsehood of the testimony is sufficiently miraculous. Or rather, it’s baldly stated as a fact that there is no falsehood, and the probability of considering it such is essentially zero. This is the only way by which declaring “I saw an alien” can possibly be counted as convincing evidence that there ever was an alien.
Not only is this ridiculous – people lie and make mistakes all the goddamn time – but it’s closed-minded in precisely the way that skeptics are so often accused of. Anytime we profess a disbelief in God, aliens, or whatever, someone will always accuse us of failing to fairly consider the evidence, and refusing to admit even the possibility that we might be in error. And yet, their outright dismissal of the chance that “A person said something which does not precisely correspond to reality” is allowed through without question.
You might know someone to be generally honest and pretty smart, and not likely to make up wild stories or totally misunderstand reality to an extraordinary degree – but given the fact that he’s claiming to have seen an alien, the notion that he is somehow in error on this occasion is not all that miraculous. Especially when compared with the alternative explanation.
The other common response, closely related to this same misunderstanding, is for the believer to derail the conversation entirely by becoming “offended” at whatever sensible questions are being asked.
It’s easy enough to understand why they might get riled. Anything but immediate acquiescence can seem to translate into “You’re calling me a liar and/or crazy” – at least, it can if you’re not a big fan of thinking things through. Cognitive biases and the like get left by the wayside, and the argument descends to the level of “I know what I saw and I ain’t crazy”.
But that’s a less interesting conversation. We should do our best to credit people with being sincere and cognitively competent whenever possible, but if you’re making grandiose claims supported by nothing more than your word, it’s only sensible for me to conclude that you are, at the very least, honestly mistaken. And I hope if I start telling people I’ve found Narnia in the bathroom cabinet that you’d call me out on it too.
So, yeah. That’s what was wandering round my head on the bus yesterday.