TEHRAN, Nov. 15 (MNA) – World Philosophy Day, with the theme of Rationality and Moderation in the Contemporary World, was held at Iranian Institute For Research In Philosophy on Monday. World Philosophy Day, on November 17 in 2016, was proclaimed by UNESCO to be celebrated every 3rd Thursday of November. Celebrating the day, UNESCO underlines the enduring value of philosophy for the development of human thought, for each culture and for each individual.