What is the supposed role of ontological expressions, the role which is supposed to be preserved across alternative languages? Before we can sensibly ask whether different sets of ontological expressions play that role equally well we must be clear on what ontological expressions are supposed to do. “Be used for asking questions about what there is” does not suffice as an answer. (Eklund 2008, 30)
It seems to me that the roles of ontological expressions change considerably across languages. The role of the objectual existential quantifier is (sometimes) to say that a description is true of something without saying what that thing is. The role of the objectual universal quantifier is sometimes to say that a description is true of everything without having to say of each thing individually that the description is true of it. Other times, the role of the objectual universal quantifier is to say that a description is true of everything without having to take a position on what things there are. In the hands of one theorist, the role of the substitutional quantifiers, roughly, is to provide truth-conditions for sentences without saying what (features of) objects make the sentence true. In the hands of another theorist, the role of the substitutional quantifiers is to provide truth-conditions for referentially opaque sentences. The role of the various Meinongian ontological notions surrounding being and objects is, well, to state Meinong’s theory of being and objects.
The uses of ontological expressions differ from language to language and from theorist to theorist. As far as I can tell, the common role for ontological expressions in different languages in the hands of different theorists is just this: to do what they are supposed to do in the language according to the purposes of the theorist. This is not to say that just any expression can be ontological, because just any expression has this sort of role. The category of ontological expressions is not defined by the role its members play. I suggested a way of categorizing existence-like expressions in my last post.
Incidentally, I think what I’ve had to say has been more-or-less in line with Carnap. I don’t think Carnap would say that what ontologists (or, given his antipathy towards ontology so described, he might say “linguistically savvy post-ontological philosopher”) ought to be doing is finding the role that ontological expressions ought to play, and then creating languages in which the ontological expressions best fit that role. He said that theorists choose whole languages according to the uses to which they would like to put them. I think he would have said, if prompted, that there is no one use for language in general. I also think he would have said, if prompted, that, for that reason, there is no one use for the ontological apparatus of language in general.