There's one curious aspect of the human psyche that's really, really hard to get rid of, and to spot the deductive error caused by it. Namely, the instinct to misattribute evidence (regardless of whether it's valid evidence or not.) This is done by the vast majority of theists, believers in the paranormal, conspiracy theorists and, sadly, even by many skeptics.
I once had a conversation with a friend about the belief in God. He told me a personal anecdote as one of the (many) reasons why he believes in God: Some years ago, when he was having a very difficult time in life, he was at a local church, and the pastor was speaking words of knowledge. My friend says that at one point the pastor started talking basically directly at him (starting with something like "there's a young man somewhere in that corner", and my friend says that he was surrounded mostly by old people and some women, so he was the only young man there) and listed quite specifically all the problems and difficult questions he had been having, gave answers to some of them and said that the rest would be resolved in time (or something along those lines.)
Now (and as I have commented in a previous post) the vast majority of skeptics make a big mistake at this point: They start discussing the event itself, and the possible natural explanations for it. However, I did know better than this.
If I had succumbed to start discussing the actual details of the event, me and my friend would have both made the same error in deduction: That the event, if true, was indeed a sign that God is real and that he affects this world (eg. by giving people words of knowledge) and that it would be a valid reason to believe in him.
No. This is a fallacy. The major problem here is misattributing the evidence. Even if the event happened exactly as he described, and even if it had indeed been something that defies any natural and logical explanation, that would still not tell us anything at all about what caused that phoenomenon or where it came from. On what grounds can one claim that the phenomenon was caused by a god? Why are all other possible hypotheses discarded in favor of this one? What's the justification?
The fact is: Even if the event did happen as described, we do not know what caused it.
A skeptic should be more savvy and note the fallacy in deduction from the very start, before going into details. It's very important to emphasize that even if the described events were real, they would still not be evidence of a god because we do not know what caused the events in the first place, what their source is. Claiming that it must have come from a god is completely unjustified.
In fact, the vast majority of "proofs" (for some reason theists really like to use that word instead of the more accurate "evidence", for some reason) for the existence of God fall into this very fallacy.
They often argue that something must have caused the Universe to exist, and that something is God. On what grounds is this claim made? They may argue that the Bible contains information and prophesies that were impossible for the people of the time to know, and therefore it must have come from God. How do they know this? They argue that archaeological evidence demonstrates that many of the events of the Bible really did happen. But how exactly is this any kind of evidence for the existence of God? They argue that miracle healings are proof of God. On what grounds? They argue that Jesus did indeed exist and did miracles. But how does this demonstrate the existence of a god? Some argue that they have seen ghosts. What's the relation to a god, exactly?
But the connection between "something extraordinary happened" and "therefore God must exist" is so strong and so deeply ingrained into the human psyche, that it's really difficult to remove and correct. More often than not, when the skeptic points out the mistake, when he points out that "even if that happened exactly as described, that would still not be evidence of any god", the believer does not understand what he means. Instead, he thinks that the skeptic is just rejecting evidence out of principle because he doesn't like it, shoving it aside without even considering it. It can be extraordinarily difficult to make the believer comprehend the nature of the deductive error.