Preface

...[the spirit] is excellent in its mobility. And understand this regarding a motion that changes something upon which it moves; by this, the primary motion—which is the cause of all others—is excluded The "primary motion" usually refers to the movement of the highest celestial sphere, which medieval philosophers believed drove all other changes in the universe..

Here he proves that animals cannot remain the same in number To be "the same in number" (unum numero) means to be the exact same individual being, rather than just a member of the same group., but certainly the same in species, and especially humans. It is doubted whether the same individual, having been destroyed in number, can be regenerated? And it seems that yes, because after thirty-seven thousand years, the constellation of the heaven will be the same throughout, just as it is now, according to Plato and the Astronomers. And therefore we will then be the same in number, and we will sit in this or that school or lecture hall, just as we do now—namely, in the "Great Year" original: "magno anno"; the period of time it takes for all the planets and stars to return to the same relative positions.. Hence Plato said that after the Great Year he must return to Athens and must read there: the reason is that the entire constellation will happen in just that way. Therefore, when the same constellation returns, the same effects will return.

This is spoken according to the opinion of Averroes Ibn Rushd (1126–1198), a Spanish-Muslim philosopher whose commentaries on Aristotle were fundamental to medieval university education. and Aristotle in the fifth book of the Physics and in the book On Generation: it is not possible because the generations and destructions of that person could not then be immediate; therefore time would come between them. And thus, something that is "one in number" is lost by a single change, according to the fifth book of the Physics. But regarding the first doubt, it must be said that after the Great Year it is possible for men to return who are very similar, so much so that they can hardly be recognized as distinct, although they are not the same in number. But you might say: if the same cause of matter remains, the effect will be the same in number. It is answered that this is true if the same measure and equally disposed matter remain, but it is not so, because time passes rapidly and does not return as the same in number, though certainly the same in species. And it can be said that today's resolution original: "resolutio"; the breaking down or dissolution of bodily matter back into its elements. is not the same in number as the resolution which comes after a thousand or four hundred years, since motion is a successive being.

It is doubted secondly, whether one animal can be perpetuated forever? And it seems so, because it is possible to find some "complexed" thing A "complexion" refers to the specific mixture of the four elements (earth, air, fire, water) and qualities (hot, cold, wet, dry) in a body. in which the elements are reduced to a mean or a middle proportion; because all destruction comes from a "contrary," and if those contraries are balanced at the highest level, they are not destroyed. But that this is possible is proved thus: because where there is a "greater equal," there is equality simply. I say that it is not possible to grant this: that which is mixed is moved by the nature of the predominant element, that is, the heaven. But to the reasoning "where there is a greater equal and lesser," etc.: respond that it is true insofar as the equal suffices and insofar as it is possible. Thus the mixture...