Super System According to Leibniz and Avecina

One of the philosophical- theological questions related to divine attributes and works is that whether the governing system of this world is the best one, and whether it is necessary for such system to be free of evil and whether it is necessary for God to create such a system. In this paper these questions are surveyed from Leibniz's and Avecina's viewpoints, especially based on the assumption that God is infinitely wise, knowledgeable powerful and good. Both philosophers believe that the evil that we see in this world does not proceed from being but it is a kind of non- being, and in order to cancel the little evil we must lose the great good.Although both philosophers see the system of this world as a necessary one, but the difference is that Avecina sees it as a philosophical necessity but according to Leibniz it is an ethical necessity.