from among you to warn you,’ just as the Almighty also says,

“Has it been a wonder to mankind that We revealed to a man from among them, ‘Warn the people’?” (10:2),

and, “Say, I am not an innovation among the messengers” (46:9), and verses of this sort.

Thus, once they knew of one concrete instance of this category, that knowledge necessarily led them to a universal judgment—that such a category does indeed exist. This is quite unlike trying to establish the matter from the outset with no prior example, which is harder, though not impossible. Noah was the first messenger God sent to the inhabitants of the earth; before him no messenger had been sent to pagan idol-worshippers, calling them to leave polytheism for monotheism. Adam and those who followed him lived at a time when all people were Muslims, as Ibn ʿAbbās said: “Between Adam and Noah were ten generations, all of them upon Islam.” When, however, God sent Noah, saved those who believed in him, and destroyed those who rejected him, that specific case proved the existence of the whole genus far more forcefully than if it had been asserted without precedent.

Those who claimed that “from the One only one can proceed” began their discourse with natural phenomena: they observed that what is cold merely cools, what is hot merely heats, and so forth. Yet even here a single effect is not produced by one cause alone; the resulting coldness, together with its cause, still needs a receptive substrate and the removal of obstacles. The effect, therefore, arises from two factors, not one—but this observation was their starting-point.

As for Ibn Sīnā and the like, their argument ran: if two effects were to proceed, the source of this would differ from the source of that, leading to composition incompatible with divine unity. This proof is derivative of the argument from composition, which they took from the theologians (ahl al-kalām) among the Muʿtazilites and others; it is not found in the writings of the leading philosophers such as Aristotle and his followers, especially the majority of the great sages. Those philosophers affirmed the divine attributes and even the reality of voluntary acts, as we have cited elsewhere. The same position was adopted by Abū al-Barakāt, author of al-Muʿtabar. When someone says that he diverged from most philosophers, he means the Peripatetics; as for the earlier sages, much of what they wrote indicates this very principle, as is recorded in its proper place.