Explaining Various Forms of Living
Alan Code and Julius Moravcsik
In Nussbaum and Rorty, eds., Essays on Aristotle's De Anima. Clarendon, 1992.

"For any one of the aspects of living mentioned, Aristotle wants to find some form or definable structure, together with some power as the underlying explanatory configuration. Perceiving, for instance, is the exercise of a certain power that results from a definable structure in a bodily organ. The power in question is the ability to receive a certain kind of sensible form without matter (424a17-19); the underlying structure is a mean state of the organ (424b1). This explains why Aristotle views the soul as both (i) structures in the living body (424b1-3) and (ii) ensuing powers (e.g., 413a25-28)." (CODE, pp. 132-133)

"The matter of a natural substance is a potentiality (dunamis), and its form is the correlative actuality which it underlies (412a9-10). In the case of a living thing, the matter (that is to say, the substratum for the actuality) is the *organic body*; the form (that is to say, the actuality which the body underlies) is the *soul* (412a17-21, b5-6)." (CODE, p. 139)

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