I think it is a little bit offensive to imply that scientists sneer at other people, or at least make frivolous assumptions about their being deluded or lying, although what I was trying to say was that I don't think it's right to think that scientists hold such distasteful and offensive views. It's never really seemed accurate in my experience. One or two people have said to me, or to my friends, something along the lines of "oh you must think I'm stupid all the time" and I get tired of saying "No, I really don't think that at all".
At any rate, the point is that there are more than the three possibilities other than deluded, lying or right. There is also the possibility of making an honest mistake.
The line between mistaken beliefs and delusion" is a bit of a difficult one to draw, and I'm not going to attempt to do it here for any specific cases, but the dictionary definition ought to do well enough. Something is a delusion if it's maintained "maintained despite being contradicted by reality" -- obviously if I were to continue to trot out the same argument above after strong and convincing evidence against it emerged, I'd be deluded. Personal accounts aren't strong enough evidence, I don't think, but that doesn't necessarily mean I think you are wrong (or deluded, or lying) -- just that I'll need more convincing than just a personal account. I don't see that this is unreasonable, either. It's meant to be healthy scepticism rather than anything else. (Admittedly, sometimes I do think you're wrong -- other times it's just as much a case of "I'm hardly going to change my views of the world based on a conversation with a stranger on the internet" as anything else. But I do find these discussions thought-provoking sometimes.)
"How do you know such beliefs are mistaken?...if you don’t know the only honest thing you can say is that you don’t know."
Well I don't know, no, but I can feel reasonably sure. I think that is also an honest assessment of the situation at the moment. I don't know -- but the evidence suggests that this sort of thing is unlikely. Why is that not being honest? As you have said, and I hope I am quoting you essentially correctly here, there is always the possibility that future technologies, or techniques, or evidence, or knowledge, emerge that show these "paranormal" (for want of a better word) goings-on to be, after all, just normal that we didn't understand. Equally, though, isn't there the possibility that this will never happen? That, after all, the explanations we have today for these (tricks of the mind, that sort of thing) were the correct ones?
This is why I was querying your "no doubt whatsoever" remark earlier. It seems odd that I must constantly be asked to concede that "I don't know", which is one of those statements that is true for anything from 0% to 99.99999999% certainty about something, so without the qualification of how much I don't know it's a bit of a meaningless thing to say anyway. Anyway, yes, it seems odd that I have to keep admitting this but that on the same topics you can be perfectly comfortable with having "no doubts whatsoever". Isn't this contradictory?
Which is the right side of the debate? I cannot say with absolute certainty that the side I'm taking is the correct one, no. Or, if you like, "I don't know". But given the current state of things, it seems unlikely -- perhaps even, for many (but not all) such phenomena, very unlikely indeed. To say that it's (very) unlikely is not a dishonest position. It's the truth, or at least the truth for the moment.
* *
I've been chopping and changing the above a few times so if it turns out to make no sense then sorry about that.