"And how are you so certain that this new incarnation of the world won't also be lacking?"

That's what he can't quite understand. If this cosmos ends, it won't truly be the same, will it? Whatever world he creates will be no more the home he loved than the one Alphinaud described him creating in the First.

"Whatever beings you create there... they will not be your friends. Your loved ones. What remained of them will be gone with the cosmos you destroyed to create it."