Aristotle as a biologist
Aristotle on Substance:
Aristotle was not a dualist on the issue of body versus soul (mind). He saw the world as consisting of an immense variety of concrete entities, or rather beings, active entities or substances. For Aristotle, a substance is a self-sufficient, self-regulated, self-actuated and self-acting form of existence. As self-sufficient, it was not reducible or subordinated in its causal manifestation to other substances, and therefore constituted the object of a science, a science of that form of being. This does not mean that substances could not contain lower-level substances whose nature they exploited in the process of being their own autonomous substance. It means that when a substance exits in an autonomous form, its sub-level substances must lose some degree of autonomy in order that they may be organized to subserve the functions and structures of the higher level substance, or primary being. Aristotle would say that without irreducible primary beings, there could be no science.
Aristotle on the mind body problem:
Aristotle saw consciousness as the defining form of the organism, not just a minor property or power of the organism, but one of such central importance that it must be identified as a defining property, or rather as the principle of being of this form of substance. The organism (or at least the animal class of organism) is a form of conscious being, a being whose very aliveness is realized as consciousness-dependent and consciousness-driven at the highest level of the organism.
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