the being whose existence is necessary in itself is not itself a being whose existence is necessary in itself. This establishes that there are two things in existence: one whose existence is necessary in itself, and another whose existence is not necessary, but which exists at one time and does not exist at another. When this latter being exists, it cannot be said that its existence is necessary in itself; rather, its existence is necessary through another.

Granted, a doubter may question whether certain things, which he has not known to cease to exist or undergo change, are necessary in themselves. But things known to cease to exist and undergo change are undoubtedly not necessary in themselves; rather, their existence is necessary through another for as long as they exist. Nor are they necessarily nonexistent when they do not exist. Neither necessity of existence nor necessity of nonexistence belongs to them by virtue of themselves. Yet, of themselves, they have nothing but nonexistence. There is a difference between something being nonexistent, with its nonexistence deriving from itself, and its being necessarily nonexistent by virtue of itself. The latter characterizes what is impossible, for nonexistence is not a thing.

Once it is established that some existing things are contingent and possible, the intended conclusion is reached: singling out such a thing for existence rather than nonexistence necessarily requires an agent that necessitates its existence. Furthermore, if its very essence admits of nonexistence, then its attributes and dimensions do so all the more. Thus, its specification