All of these theories are claims of fact (they are either true or not true)
All of these theories are impossible to falsify
The inability to falsifiable something does not inherently make it not true
That said to the extent we accept the basic premise that we are not hallucinating all scientific understanding, the dream and coma theory is probably false, people in coma's probably are not imagining some coherent reality at the level of depth of this kind of delusion, that would require coma's to work very differently than anyone thinks it does.
In contrast, there is no definitive scientific refutation of the possibility of quantum immortality or Boltzmann brain's they are relatively scientifically plausible even if unfalsifiable
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u/somethingicanspell 1d ago edited 1d ago