Al-Qādī then substantiated this by arguing that such precedence and posteriority cannot be due to a cause inhering in what precedes and what follows. For, in the absence of one who brings it into existence, the cause has no greater claim to exist in one than in another.

The same applies to the existence of all other causes of its kind in the other possible instances of the genus in which that cause exists. Moreover, this would entail one cause preceding another, which would likewise require a prior cause. This would lead to the existence of infinitely many originated events, which is impossible.

This premise is famously disputed. Nevertheless, he invoked it against those Muʿtazilites who accept it, and did so also because, in his own estimation, he had already demonstrated it elsewhere.

He also based his proof on the premise that substances are all alike. This too is famously disputed, but he referred to his substantiation of it elsewhere.

This alternative can be refuted without the proofs on which he relied. The discussion concerns the coming into being of events that occur earlier or later. Causes cannot inhere in these events while they are nonexistent; they can inhere in them only when they exist. Thus, their coming into being cannot be due to something that inhered in them before they came into being, for what is nonexistent cannot bring something existent into being, nor can it be a cause of something existent.

But their use of these roundabout approaches, involving doubtful points and lengthy argumentation, rather than