It is astonishing that these people—this man and others like him who discuss the Necessary Existent according to Ibn Sīnā’s method, making composition the principal basis for their denials—raise objections in their proof of the Necessary Existent that necessarily invalidate what they have said in denying composition. These objections do not, however, undermine the impossibility of infinite regress. Nevertheless, they raise them in the course of that proof as challenges to the refutation of infinite regress, which they have made one of its premises. Thus they remain perpetually engaged in defending negation with falsehood. Yet if they supported affirmation with some of what they use to support negation, that would suffice and demonstrate the falsity of negation.

To explain: when they established the Necessary Existent, they made the proof of its existence dependent on refuting infinite regress. For they said that a contingent existent must have a cause that determines and brings about its existence. Either the process continues infinitely, so that every contingent existent has a contingent determining cause, resulting in an infinite succession of contingent causes and effects, or it ends in something necessary in itself. They then asked, “Why should infinite regress not be possible?” This has already been discussed elsewhere.

Among their most significant objections is their question: “Why should the aggregate not be necessary by virtue of its parts, which form an infinite succession, each being necessary by virtue of another?” This question was mentioned by al-Āmidī