Analyzing and Comparing the Ontological and Epistemological Stance of Active Intellect for Avicenna and St. Thomas

The Agent intellect of Aristotle has different position in later philosophers’ thoughts. Each, according to their need and the vacuum in their philosophy would determine the position of the agent intellect. Plato considered ‘Universals' as self-subsistance, immaterial and permanent which were not in the sensible world. He had not felt that there would be a need for agent intellect; however Aristotle, contrary to his master put ‘Universals' in sensible things, and to be able to explain the concept of universals, required intellect. Since Aristotle discussed vaguely about the intellect and compared it with the sense, after him, exponents and commentators, extracted agent intellect from his philosophy, or like Alexander of Aphrodisias who considered it as a transcendent and supernatural being or put it beyond the human soul like, Muslim philosophers, Al-Farabi and Avicenna to resolve the issue of the relationship between plurality and unity as well as Knowledge. In contrast, some philosophers in the medieval age, like Thomas Aquinas despite the influence of these Muslim thinkers, regarding agent intellect took a different position and offered another explanation about Aristotle and put Intellect as part of the ‘soul'. Avicenna's agent intellect has the same position in Plotinus’ intellect. In the ontological realm, the link between separable intellects (tenth) and sensible things is offspring of emanation of the plurality of the material world. And in the epistemological realm, diffusion of the universal forms and ‘intelligible' on ‘rational soul’ and transformation from potentiality to actuality is one of its functions. Agent intellect for Thomas, according to him, is more Aristotelian and merely has epistemological position. Agent intellect for him is abstractive agent; it abstracts the intellectual forms from sensible things and actualizes them. In the ontological realm, agent intellect located in human soul and has no ontological and causal functions