What role does human psychology and neuroscience play into all this? When you say things can't be measured, what about measurements concerning how humans can be primed to believe in completely fabricated "spiritual" experiences or how we, as a species, often put meaning to things when no such meaning exists due to our habit of pattern matching and labeling?

My current view is we'll discover much of what people perceive about what changes their reality really is their own perceptions at work. It's like being told the wine you're about to drink is really expensive and got a very high score. Your tastebuds actually respond differently.

Some books which have influenced me regarding human perceptions: Thinking, Fast and Slow and Predictably Irrational.