Mulla Sadra on the Logical Problems of the Negations of “the Most Inclusive Concepts



According to the rules of quadruplet relations between concepts, Muslim logicians have proved that relation between the negations of two concepts which are equal (Musawi) or absolute-general-and-specific (‘Amm wa Khas-e Mutlaq) are, respectively, equal and absolute-specific-and-general; but these rules come across some problems when the most inclusive concepts are involved, since the negation of them are empty concepts. The argument for establishing these rules becomes invalid. The source of this invalidity is that the truth condition of negation proposition is different from affirmative equipollent proposition. However, it seems, none of the solutions, presented by Muslim logicians, are convincer except that of Mulla Sadra. He presents a proper interpretation of that difference, and by using non-conclusive proposition he succeeds in solving the problems.