Al-Farabi's Notion of Intelligence

According to Jos Decorte’s Louvain lecture notes from A History of Medieval Philosophy: “Al-Farabi (c.875-c.950) is notable as having made the epoch making distinction between essence and existence…Existence is regarded as the accident of the essence which can come upon it or depart from it. At the summit of the hierarchy of being is the Neoplatonic One, identified with the Aristotelian First Cause and self-thinking intellect and also with Allah. From the One proceeds eternally the first subordinate intelligence which gives rise to the second intelligence and, on the physical side, to the highest celestial sphere. The second subordinate intelligence brings about the third subordinate intelligence and the second celestial sphere, and so forth (enzovoort). The active intellect, the tenth and lowest of the hierarchy of pure intelligences, has no sphere corresponding to it, but acts as an intermediary between the realm of intelligences and individual human minds, perpetually illuminating them with the forms of things. Al-Farabi has thus made a fusion of Aristotle and Neoplatonism. Moreover, as the cause of the existence of things, God, is also the cause of their intelligibility, our ideas or universal concepts are necessarily true (Decorte, para. 2.50-2.51).”
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