For an effect never precedes its cause, and the discussion about the origination of the act of originating is identical to the discussion about the origination itself, and so on without end. This would necessitate an infinite series of contingent causes existing simultaneously, none of which is a necessary cause—an impossibility. Hence, it is impossible that events should arise in Him after once having been absent, and they concede as much. It is likewise impossible that such events should have been eternally present in Him, for there would be no sufficient cause perpetually necessitating them. Consequently, a cause that necessarily produces the celestial sphere together with its events while withholding those very events cannot exist—and this is precisely what needed to be shown.

Moreover, Ibn Sīnā and his followers may be addressed as follows: You abandoned your predecessors’ method of demonstrating the First Cause through motion and adopted the route of existence, claiming, “We shall prove the Necessary Existent by existence itself; motion is not required.” Yet in the end you proved the First Cause by motion—the motion of the heavens—exactly as the ancients did. If that method is sound, it deserves neither censure nor abandonment; but if it is unsound, it should not be taken up at all.

Should someone say, “Both methods are sound,” we reply: Neither achieves the intended goal. The argument from motion yields only a final cause; it does not establish a Creator who brings the universe into being. The argument from existence merely establishes that a Necessary Being exists; it does not determine that this being is the First Mover of the heavens, nor that it is distinct from the heavens, nor even that its existence is separate from the world—unless one adds to it the device of denying attributes under the guise of avoiding what you call ‘composition.’ That procedure has already been shown to be invalid elsewhere, and it remains invalid even should the attributes be denied, because