This species of idolatry is even graver than the polytheism of the pagan Arabs, the Christians, and the like. Those earlier groups still affirmed that the Maker is knowing and acts of His own free will, and that any intercessor must seek His leave and supplicate Him. Yet they nonetheless upheld intercession without His permission, ascribed intercession to those who possess none, worshipped the supposed intercessor and entreated him instead of God, and fashioned an image in his likeness to which they bowed. Devils would enter those idols, speak through them, and at times show themselves to the temple custodians—phenomena whose counterparts are still found today in many places.

Remaining remarks concerning the five “substances”:

They claim that “substance” is a genus under which fall four species—the intellect, the soul, matter, and form—while the fifth is body. Once their thesis is examined closely, however, it becomes clear that the “intelligibles” they posit exist only in the mind, as universals that have no external reality. Even among their own supporters and admirers, figures such as Ibn Ḥazm have conceded this.

Refutation of the claim that the unseen realm is the intelligible world:

Whoever maintains that the unseen world about which the messengers informed us is none other than the intelligible realm affirmed by these philosophers is among the most misguided of people. Ibn Sīnā, along with those who follow his path—al-Shahrastānī, al-Rāzī, and others—argue that the “theologians” affirm an intelligible world and rebut the “naturalists,” who recognize only the sensory world. They further claim that the intelligible world they champion is precisely the unseen reality the messengers commanded belief in, such as the existence of the Lord, the angels, and Paradise.

The matter is not so. When what they call “intelligibles” is examined, one finds that it has no existence except within the intellect itself. They are labeled “abstracts” and “separate entities” only because the mind abstracts universals from particulars.

As for calling them “separate,” the term originally arose from the notion that the rational soul separates from the body and thereafter becomes pure intellect; they likewise applied the label to whatever is linked to matter while governing it—such as the soul before death.