of contingent things exists through its individual members, then the other upon which the contingent thing depends would itself need something else, even though neither of these dependent things can do anything whatsoever to make itself self-sufficient.

This becomes clearer when we consider that, in the absence of a fully sufficient cause, a contingent thing is impossible, not possible. By a fully sufficient cause, I mean one whose existence necessarily entails the existence of its effect. Its impossibility, however, is due to something else. Thus, if every contingent thing has a contingent cause—and a contingent cause is not a fully sufficient cause, since it exists only through something else, every contingent thing being dependent on something else—then, with its existence considered apart from a fully sufficient cause, each of them would be impossible. Positing infinitely many impossible things makes their impossibility all the stronger. Under these circumstances, their aggregate cannot be possible, let alone necessarily existent.

It is therefore clear that the aggregate of infinitely many contingent causes is impossible. Hence, it cannot be said:

“It exists as an effect of its individual members.”

For what is impossible cannot exist, whether as an effect or otherwise.

This is clarified by the fact that positing an effect without a cause is impossible. An existing contingent thing is an effect of something else. Thus, if infinitely many contingent causes are posited, each of them being an effect, then infinitely many effects have been posited.

It is self-evident that the existence of infinitely many effects does not entail their independence from a cause.

If it is said:

“The aggregate is an effect of its individual members,”

then an effect has been added to infinitely many effects, and this does not entail their independence from a cause.