My mental disorder point was to illustrate a situation when we can determine an internal belief that seems to be convincing to the person having the experience to be objectively (as much as that can be asserted) false. What I'm talking about is how you can go about determining if something that a person is experiencing internally has any connection to a truth or reality or is a delusion.

Whatever these experiences are, suppressing them is making people sick. Whenever people are given permission to explore the mythological content they have a better chance of coming through.

Even if that was the case (and I'm not entirely convinced it is) can you claim that the myths are true because of that? Making that conclusion will in my opinion be faulty logic.

Coming back to the claim of people being wrong about the things they learned during mystical experience / psychosis, I point you to Carl Jung who described these experiences as the dream world overlapping reality.

In that case, Carl Jung made an unsubstantiated claim. That's in essence one of the problems of pure philosophy, if you don't go and test your claims and see that they conform to reality, you might as well be describing your own imagination instead of the real world.

If we choose, we can learn about ourselves though our dreams. Let's assume there are no multidimensional realities beyond the physical for a moment. This dream content can reveal to us information about our own subconscous mind.

If the dream world starts to overlap reality, it can contain content that can help us learn about ourselves. It can also allow us to process trauma and more.

There are a lot of if-s here. The fact that dreams might help us understand ourselves better (if that's at all the case as I see that as unproven as of now as you probably do yourself if you are consistent in your belief/disbelief), does not mean they have any relation to the reality that exists outside of our consciousness. The fact that they might provide information about our internal state does not mean that they contain any real and reliable information about the external state of reality and the universe as a whole.

Even if we accept the idea that non-ordinary states as you called them are in fact healthy for the human psyche, does that tell us anything about the state of reality outside of our human psyche? I maintain that it doesn't. It's like saying that since optical illusions fool all of us, then science should consider that the lines are indeed different lengths instead of the same one. Why would you use subjective experiences as a basis to try and justify things that can be measured objectively?

In this instance I feel that scienctific bias towards the need to not allow the possibility of a spirit world is in fact contributing to a global mental health epidemic.

I think using the word bias here is unfair and fallacious. It's by no means scientific bias to see that we have found no objective evidence that a spirit world exists. The only evidence you might have would be internal experiences of people which simply cannot qualify as objective especially when those experiences are not reliable. My example with the visual illusion is indeed consistent among our species while the interpretation and experience of the spirit world differs vastly among cultures. So if those experiences are not even consistent and often contradict each other, how could you base any rational claims on them?

Perhaps a compramise is for science to recognise the power of myth, the power of fiction, the power of storyteling.

Why would you say that science does not recognize the power of myth, fiction or storytelling? Don't you think psychologists, neurologists and anthropologists study those things extensively among others?

Psychology has seen Narrative Therapy emerge as an effective model.

The fact that something is an effective psychological therapy doesn't mean that what a person undergoing the therapy would infer from the experience would be true. For instance, it would be comforting and possibly psychologically beneficial to tell a child that their deceased pet lives on a farm upstate now, but that wouldn't mean that the knowledge the child would acquire would be correct. It would indeed be false as successful psychological therapy is not evidence for universal truth being communicated. The fact that fiction might be more comforting than the truth for some doesn't magically change it from fiction to reality.

But on a much larger scale, if science doesn't believe storytelling is powerful then they should look to the money being invested and made in the the film and tv industry. Or even better, look to advertising. If stortelling doesn't affect behaviour then why do advertisers spend billions and billions on it. They wouldn't do it if they didn't get return on investment.

Statements like "science believes" or "science doesn't believe" are at all times fallacious. Science - not a homogenous community, not an institution, so no official opinion of science. Most scientists might agree on something and accept it as true, but it's rarely all.

The fact that an idea, concept or claim affects our behavior is no evidence for reality and the truth of the claim. Neither does return on investment.

So the compramise could be science saying 'mythic content is powerful and should be respected.

Science doesn't say anything as pointed above. It is a tool that allows us to evaluate claims against reality. If the evidence is pointing in a certain direction, it doesn't really matter how people feel about it as it has no effect on if it is true or false. Why would you want a dishonest compromise anyway?

From an atheist point of view, perhaps 95%of thepopulation is suffering from some form of mental illness. If this is the case, if you want them to be healed of their delusion I suggest accepting the content as Myth (read fiction) but also accepting that Myth is powerful and engaging with these myths on their own terms instead of suppressing them may lead you to your goal more effectively.

Not from mine. I wouldn't say religion is a mental illness. If you'd like to make the case that it behaves like a mental disorder, you could, but that is by no means required or productive.

I think the proper way to deal with a delusion is through being reasonable. Discussing what is true, false, likely, unlikely, logical or logically fallacious is by no means suppression of ideas. Why do you think accepting false premises would be in any favor of an honest discussion and real seeking of truth?