Avicenna and the Issue of the Intellectual Abstraction of Intelligibles

Al-Farabi (d. 980 CE), Avicenna (Ibn Sina, d. 1037) and Averroes (Ibn Rushd d. 1198), widely known classical rationalists in the Arabic/Islamic philosophical tradition and strongly infl uential sources for Latin philosophy in the High Middle Ages, all thought themselves to be following Aristotle’s lead regarding the intellectual abstraction of intelligibles in the formation of necessary and unchanging scientific knowledge. For Aristotle it is clear that sensation is a potentiality for apprehending or coming to be individual sensed objects found in the world exterior to the human soul. This takes place by way of a separation of the forms of sensibles from matter and a reception of them as an actualization of the senses of the soul. 1 In an analogous fashion, intellectual knowing is a potentiality for apprehending or coming to be in act non-individuated intellectual forms (noeta) that are somehow in individuated particular sensible things. Although Aristotle says that “the objects of thought are in the sensible forms” (De Anima 3.8, 432a5), the analogy with sensation breaks down when it comes to the objects intellectually known. The reason for this is that the nonindividuated or universal forms of human knowledge are not in the sensibles in act as they must be in the intellect. 2 Again following Aristotle De Anima 3.4 and 3.5, these thinkers hold for a part of intellect that is passive (ginesthai) or receptive of all things and another part that is active in making (poiein) all things, this latter described as a disposition like light (hōs hexis tis, hoion to phōs), this as well describing the active agent as acting like light. This second part, which the Arabic tradition called the Agent Intellect (al-‘aql al-fa”l), sometimes describing it also as Active Intellect, al-‘aql al-fa‘il, was understood per Aristotelem to be an eternal (aidion) cause of the intellectual forms in the human intellect. It was accepted that, without a grounding in separate eternal intellect, there may well be generalization or abstraction – in some sense of the 57term? but scientific knowledge understood as true, necessary and unchanging will not be achieved. 3 Of course, in Posterior Analytics 2.19 Aristotle writes of sensory experience and provides the image of a retreat gradually coming to a halt, saying, “The soul is so constituted that it is capable of the same sort of process” (Posterior Analytics 100a14, Aristotle, 1956). This process somehow establishes the universal in the soul even though perception is of the particular. He describes this as taking place by induction, writing, “Clearly then it must be by induction (epagōgē) that we acquire knowledge of the primary principles, because this is also the way in which general concepts are conveyed to us by sense-perception.” These are “first things” (ta prōta) or primary principles or premises required by demonstration. And the Arabic tradition understood Aristotle to hold for the necessity of demonstration in the formation of scientific knowledge, something that stringently requires not only proper syllogistic form but also first premises that are known to be true, not just supposed or simply generalized on the basis of experience. 4 For the Arabic tradition, Aristotle?s doctrine of intellectual understanding required the involvement of that separate Agent Intellect to provide a solid foundation for human scientific knowledge by way of intellectual abstraction