Abstract
Vetter (2015) develops a localised theory of modality, based on potentialities of
actual objects. Two factors play a key role in its appeal: its commitment to Hardcore Actualism,
and to Naturalism. Vetter’s commitment to Naturalism is in part manifested in her
adoption of Aristotelian universals. In this paper, we argue that a puzzle concerning the
identity of unmanifested potentialities cannot be solved with an Aristotelian conception of
properties. After introducing the puzzle, we examine Vetter’s attempt at amending the Aristotelian
conception in a way that avoids the puzzle, and conclude that this amended version
is no longer to be considered naturalistic. Potentiality theory cannot be both actualist
and naturalist. We then argue that, if naturalism is to be abandoned by the actualist, there
are good reasons to adopt a Platonist conception of universals, for they offer a number of
theoretical advantages and allow us to avoid some of the problems facing Vetter’s theory.