Aristotle's "De Anima" was all about creating a third option for analyzing natural phenomena that didn't rely on either the sophists / pyrrhonists slipperiness or any kind of metaphysical essentialism. This breezy pluralism is what has proven attractive to many people even since we've learned that the atomist metaphysicians were, in fact, correct all along.
One of the standard challenges to the definition of any living thing would be eating: a deer, say, survives by eating grass. ...
Rationally, then, where does the deer end and the grass begin? Many contemporary philosophers are happy to let this land as a nice spot of ecological woo-woo and feel all wooly-headed. Likewise, both of the non-Aristotelian crews I referenced would be happy to assert that there was really no deer and no grass in the first place, and we draw pragmatic distinctions between grass and deer as it suits our purposes. Not Aristotle, however. Let us cleave the deer from the grass!
