Page:A History of Mediaeval Jewish Philosophy.djvu/412

354 of being eternal, such as the heavenly bodies, time, motion, the form of the earth, and so on. If these are proven to be eternal, the world is eternal; if not, it is not. A general principle to help us distinguish a thing having an origin from one that has not is the following: A thing which came into being in time has a purpose. An eternal thing has no purpose. Applying this principle to the heavens we find that all about them is with a purpose to ordering the sublunar world in the best way possible. Their motions, their distances, their positions, their numbers, and so on are all for this purpose. Hence they had a beginning. Aristotle's attempts to explain these conditions from the nature of the heavens themselves are not successful, and he knew it. Again, as the heavenly bodies are all made of the same fifth element (the Aristotelian ether), the many varieties in their forms and motions require special explanation. The only satisfactory explanation is that the origin of the heavenly bodies is not due to nature and necessity, which would favor eternity, but to will and freedom, and the many varieties are for a definite purpose. Hence they are not eternal. ^^^

Gersonides then analyzes time and motion and proves that Aristotle to the contrary notwithstanding, they are both finite and not infinite. Time belongs to the category of quantity, and there is no infinite quantity. As time is dependent on motion, motion too is finite, hence neither is eternal. Another argument for creation in time is that if the world is eternal and governed altogether by necessity, the earth should be surrounded on all sides by water according to the nature of the lighter element to be above the heavier. Hence the appearance of parts of the earth's surface above the water is an indication of a break of natural law for a special purpose, namely, in order to produce the various mineral, plant and animal species. Hence once more purpose argues design and origin in time.

Finally if the world were eternal, the state of the sciences would be more advanced than it is. A similar argument may be drawn from language. Language is conventional; which means that the people existed before the language they agreed to speak. But man being a social animal they could not have existed an infinite time without language. Hence mankind is not eternal. ^^^

We have just proved that the world came into being, but it does