I have often been asked how we should evaluate arguments from consensus. That’s where someone says “the consensus of experts is that P, therefore we should agree P is true.” On the one hand, this looks like an Argument from Authority, a recognized fallacy. On the other hand, we commonly think it should add weight to a conclusion that the relevant experts endorse it. Science itself is based on this assumption. As is religion, lest a religionist think they can defeat science by rejecting all appeals to authority–because such a tack would defeat all religion as well, even your own judgment, since if all appeals to authority are invalid, so is every appeal to yourself as an authority (on your religion, or even on your own life and experience).
And yet, it is often enough the case that a consensus of experts is wrong (as proved even by the fact that the scientific consensus has frequently changed, as has the consensus in any other domain of expertise, from history to motorboat repair). And our brains are cognitively biased to over-trust those we accept as authorities (the Asch effect), putting us at significant risk of false belief if we are not sufficiently critical of our relying on an expert. It’s only more complicated when we have warring experts and have to choose between them, even though we are not experts ourselves.
So what do we do?