Independence of Nasir Al-Din Al-Tusi's Approach from the Point of View of the Peripatetic on the Acquisition of Perceptions

As a semi-Peripatetist semi-illuminationist philosopher, Nasīr al-Dīn al-Tūsī (1200-1273 AC/ 597-672 AH) was well acquainted with Suhrawardī's philosophical thoughts (hikmah al-ishraq) such as idea of intuition and his illumination science; so that some scholars have called him a pure illuminationist. Nevertheless, the influence of Suhrawardī's theory on the issues of perception and cognition is not seen in his works. In other words, Al-Tūsī does not accept illuminative-based knowledge of presence ('ilm hudurī) emphasizing that the acquired knowledge agent is something other than himself. On the other hand, unlike Avicenna's approach (980-1036 AC / 370-428 AH), and also other peripatetic philosophers, in explaining the theory of Absār, Tūsī considers the theory of "radius departure" (khurūj al-shu'ā'), as an autonomous theory. He also introduces rational perceptions through the process of "Impresion" (Inṭibā') rather than "abstraction" (tajrīd). In this article, by examining the various logical and philosophical works of Nasīr al-Dīn al-Tūsī, we try to show that in the matter of knowledge and perception, Tūsī has not been an imitating philosopher, either imitating Peripatetic philosophers, or illuminatist ones. Rather, he has taken a new approach in this field. Therefore, his point of view can be examined from two aspects: First, the negative aspect, in which Tūsī denies the "knowledge of presence (al-'ilm al-huzurī)." The second is the affirmative aspect, which expresses the theory of the impression (intibā') of rational perceptions.