Have you not found, like me, that they are the origin of the opinion so
generally diffused throughout antiquity touching spectres and manes? A
man deeply afflicted at the death of his wife, or his son, sees them in
his sleep; they have the same characteristics; he speaks to them, they
reply; they have certainly appeared to him. Other men have had similar
dreams. It is impossible, then, to doubt that the dead return; but it is
certain at the same time that these dead--whether buried or reduced to
ashes, or lost at sea--could not reappear in their bodies. It is, then,
their soul that has been seen. This soul must be extended, light,
impalpable, since in speaking with it we cannot embrace it. _Effugit
imago per levibus vetitis_ (Virgil). It is moulded, designed upon the
body which it habited, since it perfectly resembles it. It is given the
name of shade or manes, and from all this a confused idea remains in the
head, which perpetuates itself all the better because nobody understands
it.--_Dict. Phil._ (Art. "Somnambulists and Dreams" ).