The distinction they posit between the two categories—soul and intellect—ultimately derives, in their view, from the human being himself. At one moment the self is in the body, governing it, and is therefore called a “soul”; at another it is separate from the body and is then called an “intellect,” for it has grasped the intelligibles and thereby become an intelligible world that corresponds to external reality. On this basis they labeled the ten separate movers “intellects” and the celestial movers “souls.” They nonetheless disagree: are these merely accidents inhering in a body, or are they immaterial substances? The two opinions divide them.

When scrutiny is applied with due rigor, the true nature of their statements in this matter uncovered, and the ambiguities of their equivocal terms removed, nothing remains of their so-called “abstract intelligibles” except what a person conceives within himself—universals such as humanity, animality, the general shared notion of existence, and the like. As for anything that exists independently outside the mind and is counted among the intelligibles they affirm, it has no reality whatsoever.

For this reason, anyone who thinks that the realm of intelligibles upheld by these philosophers is the unseen world of which the messengers—may God’s blessings be upon them all—have spoken, is mistaken. A number of writers have tried to reconcile the philosophers’ claims with the reports of the messengers, as can be found in the words of al-Shahrastānī, Abū Ḥāmid, al-Rāzī, and others. They equate the distinction between the intellectual world and the sensory world with the distinction between the unseen (ghayb) and the witnessed (shahādah). Yet the matter is not so, for the intelligibles they posit are nothing but concepts within human minds—accidental qualities subsisting therein.

As for the “intelligible realm” they claim to exist while being forever imperceptible to the senses, they have no proof for it. Accordingly, when they felt compelled to demonstrate its existence, they simply asserted it