When a capable agent refrains from an act because he does not will it, that abstention in no way nullifies his ability to perform it—unlike the case in which he does not act because he is unable. A truly capable agent may bring about either of two contraries, willing each in turn; what is impossible is to enact both simultaneously, for that is intrinsically impossible.

Were the action of a capable agent contingent on another’s assistance, or were it prevented by another, he would not be capable in and of himself. This is one of the proofs of divine oneness: the Lord must possess power by His very essence, for it is impossible that His power be derived from another. Likewise, two self-subsisting agents cannot converge upon the very same act. The efficacy of one would then depend on the absence of the other’s efficacy at the moment the first acts, and it is impossible for two complete powers—or two independent actors—to unite over a single deed. The details of this are expounded elsewhere.

Our purpose here is to state that, if one were to suppose that His power, will, and every requisite for the act are, at the moment the act occurs, exactly as they were when the act had not yet occurred, such a supposition is necessarily impossible—just as it is impossible with respect to any fully operative cause. The occurrence of the act must be distinguished by a feature that is absent when the act has not yet occurred.

As for the early generations, the leading Imams, and the foremost authorities of ḥadīth—who hold that Allah has ever been speaking whenever He wills, and that volitional events have ever arisen with respect to Him—none of the contradictions that beset these various schools of theologians and philosophers apply to them.