"Why is there any world at all, and why is it the way that it is? ... we cannot find in any of the individual things, or even in the entire collection and series of things, a sufficient reason for why they exist. 

Let us suppose that a book on the elements of geometry has always existed, one copy always made from another. It is obvious that although we can explain a present copy of the book from the previous book from which it was copied, this will never lead us to a complete explanation, no matter how many books back we go, since we can always wonder why there have been such books. 

What is true of these books is also true of the different states of the world ... however far back we might go into previous states, we will never find in those states a complete explanation for why there is a world at all, and why it is the way it is. 

I certainly grant that you can imagine that the world is eternal. However, since you assume only a succession of states, and since no reason for the world can be found in any of them ... it is obvious that the reason must be found elsewhere. ... even if we assume the eternity of the world, we cannot escape the ultimate and extramundane reason for things, God. "