Illuminationist or ishraqi philosophy is a type of Islamic philosophy introduced by Shahab al-Din Suhrawardi in the twelfth century CE.
Influenced by Avicennism and Neoplatonism, the Persian or Kurdish, philosopher Shahab al-Din Suhrawardi (1155–1191), who left over 50 writings in Persian and Arabic, founded the school of Illumination. He developed a version of illuminationism (Persian حكمت اشراق hikmat-i ishrāq, Arabic: حكمة الإشراق ḥikmat al-ishrāq). The Persian and Islamic school draws on ancient Iranian philosophical disciplines, Avicennism (Ibn Sina’s early Islamic philosophy), Neoplatonic thought (modified by Ibn Sina), and the original ideas of Suhrawardi.
In his Philosophy of Illumination, Suhrawardi argued that light operates at all levels and hierarchies of reality (PI, 97.7–98.11). Light produces immaterial and substantial lights, including immaterial intellects (angels), human and animal souls, and even 'dusky substances', such as bodies.
Suhrawardi's metaphysics is based on two principles. The first is a form of the principle of sufficient reason. The second principle is Aristotle's principle that an actual infinity is impossible.
None of Suhrawardi's works were translated into Latin, and so he remained unknown in the Latin West, although his work continued to be studied in the Islamic East. According to Hosein Nasr, Suhrawardi was unknown to the west until he was translated to western languages by contemporary thinkers such as Henry Corbin, and he remains largely unknown even in countries within the Islamic world. Suhrawardi tried to present a new perspective on questions like those of existence. He not only caused peripatetic philosophers to confront such new questions but also gave new life to the body of philosophy after Avicenna. According to John Walbridge, Suhrawardi's critiques of Peripatetic philosophy could be counted as an important turning point for his successors. Although Suhravardi was first a pioneer of Peripatetic philosophy, he later became a Platonist following a mystical experience. He is also counted as one who revived the ancient wisdom in Persia by his philosophy of illumination. His followers, such as Shahrzouri and Qutb al-Din al-Shirazi tried to continue the way of their teacher. Suhrewardi makes a distinction between two approaches in the philosophy of illumination: one approach is discursive and another is intuitive.