Did Aristotle have a Doctrine of Existential Import?

Abstract Modern logicians hold that traditional logic makes a serious error by accepting the subalternation thesis , the thesis that universal affirmatives imply matching particular affirmatives. But some traditional logicians (e.g., Al-Fārābī, Abelard, Ockham) presented doctrines of existential import of categorical propositions that include subalternation, and some modern studies of Aristotle’s logic take him to assume one of the doctrines. This article argues that such interpretations have serious problems and proposes a radically different interpretation. On the new interpretation, called the no-import interpretation , Aristotle takes both singular and general categorical propositions (including singular and particular affirmatives) not to have existential import. In proposing and defending this interpretation, the article gives a close examination of two influential interpretations of his views on existential import: (a) the affirmative–negative interpretation , which takes him to hold that affirmative categorical propositions have existential import while negative ones do not, and (b) the non-vacuity interpretation , which takes his system of logic to presuppose or require that empty terms do not figure in general categorical propositions the system deals with. The article argues that Aristotle holds theses about singular and general categorical propositions that conflict with these interpretations, and that examination of the theses leads to the no-import interpretation.