Aristotle's Definitions of the Soul: "De Anima" ii, 1-3

doctrine of the Metaphysics requires us to say that the new definition can
only in a secondary way give the essence of anything (1030 a 17, ff.). This
qualification leaves our earlier results unaffected.
The upshot of those results is that the definition of the soul as the form of
the body (in any of its variants) should not be understood in the usual way.
Correctly understood it does not entail that every soul is embodied. It does
entail that certain types of embodied forms are souls but it does not tell us
which types those are. So, as far as the definition goes, not only the intellect
but other faculties of soul as well might exist unembodied or disembodied.
Aristotle does not believe that many, if any, of these other functions can
exist unembodied but that is a matter which he undertakes to prove by
showing that these functions require the operation of specific bodily organs
(see 413 b 13-29). The matter is not settled by the definition.
It follows from this that in Aristotle's view the mind-body problem is not
one that can be settled on what we would call conceptual grounds. The
definition of soul in II, 1, being a nominal or semantic definition, is an
account by reference to what is more familiar to us. As such it explicates
what the common understanding of the notion of the soul is (Topics
141 b 3-14). But this common understanding focuses on certain special
cases of soul and does not incorporate any fully general description of what
a soul is. So one cannot say in general on the basis of this account of the
ordinary concept of the soul what the relation between soul and body is.
11. We may conclude by noting certain implications which the results of
ur study of Aristotle's definitions of the soul have for the interpretation of
Aristotle generally.
At the end of De A nima II, I Aristotle speaks of his initial account of the
soul as a sketch "in outline" (Tv$vi). As we saw at the outset, he characteristically
uses this expression to describe initial accounts of the sort which
are "more intelligible to us" and which give only derivative facts about
some entity rather than its essence." Other passages ally accounts described
in these latter ways with nominal definitions. In Physics I, 1 (184 a
16 - b 14) an account which is more intelligible to us is said to be of the
same sort as a nominal definition. And in De Anima II, 2 (413 a 13, ff.) an
account which gives only a fact is said to be like a "conclusion" or nominal
definition. This makes it apparent that an account "in outline" is likely to
have important similarities, at least, with one or another type of nominal
definition.
A striking proportion of what Aristotle says in his works - about everything
from the syllogism to substance to the highest good - is qualified by
use of the expression "in outline" and the related expressions applied in De
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