Aristotle believes that there is an internal active intellect in every human individual that is part of the soul and is eternal and grounds all intelligible entities. Avicenna argues for the existence of a unique external active intellect for all human individuals. He not only contends that the primordial intelligible entities as well as the intellectual and perceptual forms should be attributed to this intellect rather he suggest that the latter is the bestower of all existing forms in the material world. In this essay we assay the reasons and necessities that are required by the existence of the Active Intellect according to these two philosophers and proceed to demonstrate that attribution of these affairs to internal active intellect is preferred. Moreover, the existence of external active intellect with the mentioned functions is confronted with serious challenges.
