As far as Tuplas go, Tulpas are mainly about qualia.
Aren't hallucinations about qualia? At a glance, science seems pretty well informed about hallucinations. What's the important difference?
If you are looking at far out mental phenomena there no reason to expect that they are well investigated by scientists.
What makes tulpas significantly more far out than hallucinations?
Finding a person who hallucinates is pretty easy. You go to your nearest asylum and go through the patients and you will usually find someone who has hallucinations.
As luck would have it the patients are also bound for years to a specific location and might have no possibilty to opt out of your study.
Finding people as test subjects who spent halve a year doing a hard mental practice is harder. Experiments that require that you have test subjects who spend a lot of time on a hard mental practice are much easier to do.
...At a glance, science seems pretty we
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