Abstract:  It has long been debated whether objects are ‘sortally’ individuated. This paper begins by clarifying some of the key terms in play—in particular, ‘sortal’, ‘individuation’, and ‘object’. The term ‘individuation’ is taken to have both a cognitive and a metaphysical sense, in the former denoting the singling out of an object in thought and in the latter a determination relation between entities. ‘Sortalism’ is defined as the doctrine that only as falling under some specific sortal concept can an object be successfully singled out in thought. It is argued that such a view is too strong, but that a weaker one, ‘categorialism’, can be defended, this implying that a thinker cannot successfully single out an object in thought without having at least an implicit grasp of the criterion of identity that the object satisfies.