Each dream not necessarily is a strictly spiritual experience. So, contradicting what Kardec wrote. Or Alberto Zecua says. It doesn't coincide with the so-called «astral voyage». The «dream» is a consciousness experience in its generality. But not reduced to the spiritual field. We may have oneiric experiences just "psychologic(al)". Or have "precognitive" dreams. And these also have their spiritual frameworks, which give them a part of their elements. But not in a strict way. Etc. In their majority, dreams are a composition of elements coming from those different oneiric categories. The dream belongs to the mental experience and not just spiritual. It is true that spiritual involves the mental and the physical as well. But the «strictly spiritual» is beyond the mental, because «the mental» concerns just the conscious exercise on matter or physical domain.

I've made an essay on this subject in my «The Philosophy of the Dream», of course not translated neither published because I have no money enough to spend in such an enterprise like that. And then I could understand a little better the mechanics and the meaning of the dream.

21-09-2016.