دليل افتراض: گزارش و سنجش

Ecthesis: An Account and Evaluation

Among the most useful methods in traditional logic is Ecthesis (i.e. proof from supposition), on whose whatness and structure Muslim logicians disagree. On one hand, Suhrawardi and Fakhr ar-Razi consider it as a type of syllogism in the third figure, whereas on the other hand, Nasir-ad-din Tusi does not count it among syllogisms at all. The author in this essay firstly presents an account of three logiciansʹ viewpoints and then evaluates Nasir-ad-din Tusiʹs opinions.