Human beings consist of the following: 1) a
body, or physical being, similar to that belonging to animals and animated
by the same vital principle; 2) a soul, an immaterial spirit incarnated in
the body; 3) an intermediate link which unites the soul and body.
Human beings have, accordingly, two natures:
animal and spiritual. Through the body, humans participate in the
nature of animals, with which they share instincts. Through the soul,
they participate in the nature of the spirits.
A link, known as the perispirit (or spiritual
body), unites the body and the spirit. It is a semi-material envelope,
as opposed to the fully material envelope of the body. At death, the
spirit sheds the physical body, the grosser of the two, but preserves the
perispirit, or spiritual body. The perispirit constitutes, then, an
ethereal body that the spirit can render visible, or even tangible, as in
the case of spirit-sightings.
A spirit is not, therefore, an
abstract being, a concept of thought. Rather, it is a real and well-defined
entity that, in certain situations, can be perceived by sight, hearing, and