Noneism and Allism on the Objects of Thought

Noneism is a version of Meinongianism, the view that some things do not exist. Allism is the view that everything exists, including those things that the noneist takes as non-existent. Since, there has been a discussion on whether or not one can translate the noneist theory into the allist theory and if, in that case, the differences between the two remain substantive. In this paper we propose a notion we call Theoretical Equivalence: two theories are theoretically equivalent, relative to an explanandum, if the models they produce to explain it are isomorphic. We take intentional objects – which are often considered as providing a prima facie motivation for Meinongianism – as our explanandum. We argue that noneism and allism are theoretically equivalent with respect to the problem of intentional objects, lending some support to Woodward’s translation of the noneist’s ‘to exist’ into the allist’s ‘to be actually concrete’, in the face of recent objections by Priest. We also claim, however, that while in a sense this makes the disagreement between noneism and allism insubstantial, in another sense, it doesn’t.