Two different definitions of numerical identity occur in Aristotle's works, namely: (i) "A" and "B" are both names of one thing; (ii) A and B constitute unity. These definitions can be traced back respectively to the following theories of predication: (i)' the sentences whose subjects are accidents are actually ill-formed; (ii)' in some cases the accidents are not eliminable subjects. Since (i)' and (ii)' are irreparably inconsistent, the theory of identity is inconsistent too; in this paper are explored the consequences (...) of such an inconsistence, mainly as far as the fallacies depending both on combination and division and on accident are concerned. (shrink)

In Met. Z 6 Aristotle argues, inter alias, that things which are spoken of coincidentally are different from what being is for them. Unfortunately the arguments which are aimed at supporting this claim are less than compelling, and Aristotle himself seems to cast serious doubt on their validity. The main purpose of this paper is to stress the dialectical features of Met. Z 4-6 in order to display the logical structure of the above mentioned arguments and to put forward a (...) new interpretation that vindicates what is, on my mind, Aristotle’s claim, i.e. that his first argument is actually untenable, while his second looks sound. (shrink)

The theory of predication underlying assertoric syllogistic is quite extensional. Modal syllogistic is an extension of the assertoric one, dealing with a lot of intensional notions mostly borrowed from Topics and Posterior Analytics; but Aristotle’s attempt to bring together modalities and extensional form of assertoric premisses ends in failure after all, and the puzzles he faced with in building his modal syllogistic spring just from it.