Perception is internal, regardless of it seeming to have no causative connection. People try manifesting but change a surface thought and not any element of their world view. Then the world view snaps back in, and they say manifestation isn’t possible.
We are overconfident of human independence. Even modern psychological research suggest that it’s a half truth at best. Then you could delve rationalistically into why that is and why we have what subconscious influences that we do. Does that invalidate spiritual experience and make the ancients foolish? Maybe they were more expedient and direct in some ways. If anything they lived in more desperate times. If their activities were just delusion then it would seem to suggest our ancestors were all psychotic. If so how did they survive?
There always were and always will be those who don’t want to rely on their personal experience, and don’t want to answer questions for themselves. To date the world is still full of them, and rather than having a few pharaohs we have a chaos of opposing powers and are seeing the impact. I would say we are more than a small fraction god, but like the un-resurrected Osiris we yet slumber and are powerless. In part because we choose to be.
Is agreement/concurrence of all or at least core beliefs necessary? In fact philosophy and science really only require an agreement of terms. Ideally you can substitute a term and if you can agree on meaning you are still talking about the same thing, and can have meaningful discourse. There is a necessity of an agreement of terms.
Your thoughts are welcome. Be well friends.