and effects, infinite in number, at a single instant, as well as infinitely many contingent beings at a single instant. They expressly declare this impossible, and proof establishes its impossibility. Their position also entails that no event can occur, and that events occur without a complete efficient cause. All of this is impossible.

Their fundamental principle is that an effect must coincide in time with its complete cause: it neither follows immediately upon it nor occurs after a delay. Thus, the effect accompanies the complete exercise of causal efficacy.

Many theologians say that the effect may occur after a delay.

The correct position is a third: the effect follows immediately upon its cause, neither coinciding with it nor occurring after a delay. This entails that everything other than Allah Most High has a beginning.

Their position, however, entails that nothing new can occur in existence. Rather, every contingent being would be eternal and beginningless, because its complete cause exists from eternity.

It also entails that nothing new can occur, since an event cannot occur without a newly arising cause, while, in their view, it is impossible for anything new to proceed from the First. It further entails that whenever an event occurs, infinitely many events occur. For they say:

“No event occurs until its cause becomes complete.”

The response is:

That completion is itself an event, so what completes its own cause must occur simultaneously with it, and so on. This entails that infinitely many causes reach completion, together with their effects, at a single instant.

This is impossible, just as the existence of infinitely many causes and effects at a single instant is impossible. There is no difference between the impossibility of an infinite regress in the cause itself and its impossibility in what completes the cause, since it becomes an actual cause only when it is complete.