 Note that the traditional account does not require the reduction of all expressions of the extended language; it requires the reduction only of formulas. The definition of a predicate \(G\), for example, need provide no way of reducing \(G\), taken in isolation, to a predicate of the ground language. The traditional account is thus consistent with the thought that a stipulative definition can add a new conceptual resource to the language, for nothing in the ground language expresses the predicative concept that \(G\) expresses in the expanded language. This is not to deny that no new proposition—at least in the sense of truth-condition—is expressed in the expanded language.