Summary |
Both the idea of ontological commitment and its connection to the idea of quantification are associated especially with the work of Quine. In Quine’s scheme (as in most others) the highest-level ontic category is that provided by the form of the variable itself; to be assumed as an entity is to be assumed as a value of a variable. Below this level, the question becomes one of the adoption of particular ranges of variables for particular ranges of putative entities (class variables versus individual variables, just for instance). In excluding semantically plural variables – a possiblity Quine seemingly never considered – his formulation is ‘singularist’; but this, it seems, should make no ontological difference. The idea of a distinctively ontic operator is articulated by Quine in several closely related ways - for example, ‘We commit ourselves outright to an ontology containing numbers when we say there are prime numbers between 1000 and1010; we commit ourselves to an ontology containing centaurs when we say there are centaurs’. Thus conceived, the role of the (so-called) existential quantifier is quite precise. It is not a device for expressing just any kind of existential information; it is a quite specifically ontic device, for speaking of categories and kinds of things exclusively – not for information as to numbers of the items in these categories and kinds. Ontically, what matters is purely and simply whether there are things of this or that kind or not. Quine declares: ‘Existence is what existential quantification expresses’, and continues, using the (bare plural) form, ‘There are things of kind F if and only if (∃x)(Fx)’. What the operator ∃ represents is here quantification in name only, precisely because its role is to be numerically neutral. Commonplace accounts of quantifiers stating that they specify ‘which or how many of some kind of things have some property’ misrepresent the content of the existential quantifier, in contrast with so-called numerical quantifiers (as in ‘There are exactly two prime numbers between 1 and 4’). Yet insofar as the semantics of variables, whether singular or plural, implicate countability in the first place, the question of the ontological neutrality of their use is not distinct from the unsettled question of whether talk of entities or objects itself is ontically neutral. For Quine’s claim is that ‘all traits of reality worthy of the name can be set down in an idiom of this austere form if in any idiom’ – in spirit, ‘a philosophical doctrine of categories’. But Quine frequently indicates serious concern, regarding what he calls the 'artifice' or 'reduction' of talk involving his so-called 'mass terms' to talk of entities or objects in the first place. |