A further clarification is that everything that comes into being is contingent: it was nonexistent and then became existent, and thus admits both existence and nonexistence.

Now, everyone knows that it cannot be said of a thing that comes into being that its nonexistence requires a determining cause in the same way that its existence does. Rather, it has no existence of its own at all, and, considered in itself, it warrants only nonexistence. That is, only nonexistence is established for it by virtue of itself; this does not mean that nonexistence is necessary for it by virtue of itself. Its nonexistence is therefore not intrinsically necessary, but is established by virtue of itself.

When I say “established by virtue of itself,” I am not speaking of a thing or essence established in external reality, for what is nonexistent has no established essence in external reality. Rather, the truth of the matter is that nothing belonging to it exists in external reality by virtue of itself. It can, however, exist through something other than itself. It therefore depends on something else for its existence, not for its nonexistence.

If someone says, “A contingent thing—or a thing that comes into being—depends for its nonexistence on the nonexistence of the necessitating cause,” he is told: “The nonexistence of that necessitating cause must be either necessary or contingent. If it is necessary, it follows that the nonexistence of every contingent thing is necessary, making all contingent things impossible. For, on this supposition, the nonexistence of every contingent thing is caused by a necessary nonexistence. If a thing is nonexistent because its cause is nonexistent, and the nonexistence of its cause is necessary, then its own nonexistence is necessary. The invalidity of this is self-evident.”