If it's worth saying, but not worth its own post, then it goes here.
Notes for future OT posters:
1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)
3. Open Threads should start on Monday, and end on Sunday.
4. Unflag the two options "Notify me of new top level comments on this article" and "
This is a useful general prescription against irrationality: if a belief is supported by reason and evidence then you should be able to say what evidence would make you revise it. But it's worth noting that sometimes a belief may be reasonable but really hard to imagine remotely plausible evidence that would change your mind about it. What would Donald Trump have to do that would make you think he's a progressive internationalist who favours open borders and free trade? What would ISIS have to do to convince you that they are primarily an organization dedicated to fostering peace and cooperation among people of different religions?
Clearly it's not actually unreasonable to think that Donald Trump isn't keen on open borders and free trade, or that ISIS aren't particularly into peace and cooperation. But the question you should be able to answer to justify a claim that you believe those things rationally is, I suggest, not so much "what evidence would change your mind?" but "what different evidence would have led to a different conclusion?". If Donald Trump had campaigned on promises to lower tariffs and offer amnesties to illegal immigrants, or if ISIS gave out pamphlets about peace and love and charity instead of blowing things up, I'd have different opinions about them. (Though I'd probably still mistrust both.)
So if someone can't tell you what Donald Trump could do to convince them he's a pathological liar, rather than writing them off you might instead ask them "well, then what could he have done differently that would have led you to think of him that way?".
(Where you think they're not only wrong but obviously wrong, you might reasonably take the view that anyone who thinks the evidence is so one-sided that it would take an impossible amount of future evidence to change their mind is ipso facto probably nuts. So you might write them off after all, if you think no remotely reasonable person could think the evidence overwhelmingly favours Trump not being a pathological liar.)
I agree that would be the sensible response, but I'm curious for ways to engage with people who see the world radically differently.
An ability to build particularly long bridges of consensus across particularly wide chasms of preconceptions could do the world a lot of good, if it is a learnable and teachable skill.