o states
in respect of their priority of development in a particular person, we
shall see that the state of latent possession comes first. We may
therefore define the Soul or Vital principle as _The earliest {205}
realisation (entelechy) of a natural body having in it the potentiality
of life_.

"To every form of organic structure this definition applies, for even
the parts of plants are organs, although very simple ones; thus the
outer leaf is a protection to the pericarp, and the pericarp to the
fruit. Or, again, the roots are organs bearing an analogy to the mouth
in animals, both serving to take in food. Putting our definition,
then, into a form applicable to every stage of the Vital principle, we
shall say that _The Soul is the earliest realisation of a natural body
having organisation_.

"In this way we are relieved from the necessity of asking whether Soul
and body are one. We might as well ask whether the wax and the
impression are one, or, in short, whether the _matter_ of any object
and that whereof it is the matter or substratum are one. As has been
pointed out, unity and substantiality may have several significations,
but the truest sense of both is found in _realisation_.

"The general definition of the Soul or Vital principle above given may
be further explained as follows. The Soul is the _rational_ substance
(or function), that is to say, it is that which gives essential meaning
and reality to a body as knowable. Thus if an axe were a _natural_
instrument or organ, its rational substance would be found in its
realisation of what an axe means; this would be its _soul_. Apart
{206} from such realisation it would not be an axe at all, except in
name. Being, however, such as it is, the axe remains an axe
independently of any such realisation. For the statement that the Soul
is the _reason_ of a thing, that which gives it essential meaning and
reality, does not apply to such objects as an axe, but only to natural
bodies having power of spontaneous motion (including growth) and rest.

"Or we may illustrate what has been said by reference to the bodily
members. If the eye be a living creature, _sight_ will be its soul,
for this is the _rational_ substance (or function) of the eye. On the
other hand, the eye itself is the _material_ substance in which this
function subsists, which function being gone, the eye would no longer
be an eye, except in name, just as we can speak of the eye of a statue