Editing David Kaplan (philosopher) (section)

===Quantifying in===
In his article "Quantifying In" (1968), Kaplan discusses issues in intensional and indirect (''Ungerade'', or ''oblique'') discourse, such as substitution failure, existential generalization failure, and the distinction between [[De dicto and de re|''de re'' / ''de dicto'']] propositional attitude attributions. Such issues were made salient primarily by W. V. Quine in his "Quantifiers and Propositional Attitudes" (1956).

The phrase "quantifying in" comes from Quine's discussion of what he calls "relational" constructions of an existential statement. In such cases, a variable bound by an anterior variable-binding operator occurs within a non-extensional context such as that created by a 'that' clause, or, alternatively, by propositional attitude or modal operators. The "quantifying in" idiom captures the notion that the variable-binding operator (for example, the existential quantifier 'something') ''reaches into'', so to speak, the non-extensional context to bind the variable occurring within its scope.   For example, (using a propositional attitude clause), if one quantifies into the statement "Ralph believes that Ortcutt is a spy," the result is (partly formalized):

:(Ǝx) (Ralph believes that x is a spy)
:["There is someone Ralph believes is a spy"]

In short, Kaplan attempts (among other things) to provide an apparatus (in a [[Gottlob Frege|Fregean]] vein) that allows one to quantify into such intensional contexts even if they exhibit the kind of substitution failure that Quine discusses. If successful, this shows that Quine is wrong in thinking that substitution failure implies existential generalization failure for (or inability to quantify into) the clauses that exhibit such substitution failure.