These people sought to avoid temporal events beginning to occur without a cause after none had existed, yet asserted their perpetual occurrence without a cause. What they fled to was thus worse than what they fled from—like someone seeking refuge from scorching ground in a fire.
But if it is said that volitions and acts subsist in the agent itself, determining what it brings into existence at each particular time, this invalidates their argument. Under these circumstances, it can bring one thing into existence after another while remaining perpetually active. Indeed, this invalidates their doctrine itself.
For anyone who conceives of such an agent knows with certainty that none of its acts or effects can be coeternal with it, and that each of its acts and effects must come into being, rather than coexist with it throughout an eternity without beginning or end.
If this is known of anything conceived of as an agent, it is all the more evident of one conceived of as acting by its will and power, with its acts subsisting in it.
It may then be said:
Either an infinite regress in causes becoming complete is possible, or it is impossible. If it is impossible, it follows that everything other than Allah came into being, and that He was not acting and then began to act. This invalidates their position.
If it is possible, all that follows is that He perpetually produces one thing after another. This provides them with no supporting argument; rather, it invalidates their argument and doctrine, as explained above.
The same reasoning applies to the second as to the first, so an infinite regress of effects necessarily follows.
If this necessarily follows, then it is all the more certainly possible. If it is possible, the claim that it is impossible is false, and the argument is therefore invalid.