Ghosts: lost souls, a phenomenon, or just a fairy tale?

Personally, I am convinced (this is just my opinion) that a person is self-sufficient when it comes to things that are invisible. Many have told me that they have seen ghosts (and I have had something similar), but, comparing the psychotypes of these people (and myself, as much as possible) and the circumstances in which the "visions" occurred, I am convinced that this is what I would call a "pseudo-dream syndrome," a so-called "thin" sleep, a state caused by various situational and psychophysical factors. In a normal (healthy in every sense) state, this is unlikely to happen. It usually happens to people with extrasensory (even if very weak) abilities during a period of intense mental and emotional work (stress, anxiety, proximity to death, a strong shock from something, fear due to darkness or something else, strong doubts about what one is doing, etc.). It is at such moments that the so-called "thin" sleep can occur, that is, being in a "between-world," when one can see something unreal, but, as a rule, not spontaneous, but providential. A person either receives some answer to a question that interests him, or a warning, or even a prediction (this has also happened, and it came true). I think that this is the subconscious desire of a person to hear the answer of the infinite, omnipotent, and unknowable Cosmos to his aspirations, that is, HE GENERATES IT HIMSELF - a person is simply given such abilities by God, but... this does not mean that ghosts do not exist :)
But this is a more delicate topic... I don't feel like bringing it up:D