Dahut asks her father the above question. He replies that there are many beliefs and that she, as a vestal, must know what the wisest Ysans think. But Dahut does not want to be told beliefs or philosophical thoughts. She has directly experienced communication with the seal. Not living inside a historical fantasy, what do we know on the subject? We have:
the primitive assumption that souls leave bodies temporarily in sleep and permanently at death;
multiple beliefs about where the souls go after that;
philosophical speculations and rationalizations at least from Plato;
allegedly revealed religions;
claims to communicate with the dead;
claims to remember previous lives or to experience postmortem mental states.
My observations are here and here.