Effects of Stoic Logic on the Development of the Concepts and Technical Terms of the Discussion of Conditional Propositions in the Islamic Period

Afnan and Sami al-Nishar believe that Islamic philosophers found access to the main texts of Stoic thinkers during the translation movement. Nevertheless, Josef van Ess maintains that Muslim philosophers were exposed to Stoic teachings in the course of the cultural interactions between Muslims and the residents of newly conquered regions. In the present paper, after criticizing these two ideas, the writer agrees with Dimitri Gutas’s view regarding the indirect impact of Stoic logical doctrines through the works of such logicians as Galen and Alexander of Aphrodisias. Then, by examining the concepts and technical terms which are employed by Stoic logicians in the analysis of conditional propositions and reasonings, he investigates the effects of such concepts and terms through the works of the above-mentioned logicians in the development of certain concepts such as conflict, necessity, and exception.