Making use of these principles, which will be proved later, we proceed as follows: The world is composite in all its parts. Sky, earth, stars and man form a sort of house which the latter manages. Plants and animals are composed of the four elements, fire, air, water, earth. The elements again are composed of matter and form, or substance and accident. Their matter is the primitive "hyle," and their form is the primitive form, which is the root of all forms, essential as well as accidental. It is clear therefore that the world is composite, and hence, according to the third principle, had its origin in time. As, according to the first principle, a thing cannot make itself, it must have been made by some one. But as, in accordance with the second principle, the number of causes cannot be infinite, we must finally reach a first cause of the world before which there is no other, and this first made the world out of nothing. Before criticising this proof, from which Bahya infers more than is legitimate, we must prove the three original assumptions. The proof of the first principle that a thing cannot make itself is identical in Bahya with the second of the three demonstrations employed by Saadia for the same purpose. It is that the thing must either have made itself before it existed or after it existed. But both are impossible. Before it existed it was not there to make itself; after it existed there was no longer anything to make. Hence the first proposition is proved that a thing cannot make itself. The proof of the second proposition that the number of causes cannot be infinite is also based upon the same principle as the fourth proof in Saadia for the creation of the world. The principle is this. Whatever has no limit in the direction of the past, _i. e._, had no beginning, but is eternal a _parte ante_, cannot have any stopping point anywhere else. In other words, we as the spectators could not point to any definite spot or link in this eternally infinite chain, because the chain must have traversed infinite time to reach us, but the infinite can never be traversed. Since, however, as a matter of fact we can and do direct our attention to parts of the changing world, this shows that the world must have had a beginning.