PREFACE

...they desire in reality; referencing Book 1 of the Metaphysics Likewise, he sought it with an intellectual desire, because he saw the usefulness of thinking about them.

As it is written in the second book of On the Generation of Animals, the generation of things capable of being born is eternal in its cycle. Aristotle argued that while individuals die, the "cycle" of birth keeps life going forever. Moreover, the Philosopher A standard medieval title for Aristotle. shows the cause of this eternity in the generation of animals in the second book of On the Soul, saying: "The most natural of works is for each thing to produce another like itself: so that they may participate in the divine and immortal being; for all things desire to remain forever—not as the same individual in number original: "idem in numero"; meaning the exact same physical body, but as the same kind in species." original: "idem in specie" For this reason, the Commentator The 12th-century philosopher Averroes, whose detailed explanations of Aristotle were essential to medieval science. says in the second book of On the Soul that since divine care could not make the individual human remain the same in number, it took pity on him by giving him the power to remain the same in species. And he adds: "For there is no doubt that it is better to have this power than not to have it, or not to exist at all."

This is the executive part in which the author pursues his intention by putting forward two propositions that serve his purpose. And it is divided into as many chapters and parts as will be revealed in order. Note that the generation of perfect animals In medieval biology, "perfect" animals were those that reproduced sexually or had complex organs, as opposed to "imperfect" insects believed to arise from decay. is eternal, because such things pertain to universal perfection, according to Book 1 of the Ethics. But a doubt arises, because certain animals are at times utterly destroyed.