the substance of its essence becomes like primary matter relative to those impressions, while the impressions within it act as form. Through its active faculty, it projects the forms residing within its thought and inscribes them onto corporeal matter, whereby the physical body becomes a manufactured object (masnu'an) for it. Anyone who learns a piece of knowledge possesses the form of that known object within their soul potentially (bi-al-quwwah); once they acquire it, it becomes present within it actually (bi-al-fi'l).

Primary Matter (al-Hayula) is divided into four categories: the matter of craft (hayula al-sina'ah), the matter of nature (hayula al-tabi'ah), universal matter (hayula al-kull), and prime matter (al-hayula al-ula).

The matter of craft is any physical body from which and in which an artisan executes his craft. The matter of nature consists of the four fundamental elements (al-arkan al-arba'ah). Universal matter is absolute body (al-jism al-mutlaq) out of which the totality of the cosmos is structured. Prime matter is a simple, intelligible substance (jawhar basit ma'qul) that cannot be perceived by the senses, for it is the very form of existence—the ultimate quiddity (al-huwiyyah).