He said:

"This becomes even clearer with respect to contingent existents for which no first originated member is assumed."

He said:

"Should a skeptic raise the following objection: ‘An originated contingent being is affirmed only through a cause, and that cause must be one of two things: either it is perpetually the cause of the being’s persistence, or its becoming the cause of that persistence occurred anew. If it has always been the cause of its persistence, then the contingent being would not be originated, whereas we have stipulated that it is. If, however, its becoming the sustaining cause is itself something that began, then the very fact that it is a cause of persistence—and the relation it bears to the effect—also requires another cause to maintain it once the cause that first produced that relation has come into play; for the relation between them arose on account of something, and therefore must continue on account of something. The same reasoning applies to this subsequent cause just as it did to the first. Consequently, one is compelled to posit an infinite series of contingent causes existing simultaneously.’"