Five innovative essays demonstrating how Aristotle's biology is an integral part of Aristotle's understanding of the universe.

In Animals in the World, renowned Aristotle scholar Pierre Pellegrin attempts to demonstrate that Aristotle, by proposing an original version of natural perfection, opposes the whole of the Greek tradition. Nature is perfect, not only in its harmony of a complete and well-organized whole, but also because it brings together functionally perfect individuals.