Abstract

I discuss whether the Canon of Proclus (obversion in modern logic) destroys the hope of having an acceptable interpretation of Aristotle’s logic. The problem arises when Aristotle, in some passages of his logical writings, agrees with the idea that, in general, negations follow from affirmations, but not reciprocally. Since however certain ancient tradition of commentaries explains that, because of the Canon of Proclus, some propositions can follow reciprocally one from another, as if they were equivalent, I discuss whether this interpretation of Aristotle’s logic is valid and not an attempt to transform it into a formalistic theory.