Carnap is concerned with how to deal with definitions. What is good for logical vocabulary, he says, must also be good for metalogical vocabulary.
Carnap uses meaning postulates to adapt the format of logic to the analysis of natural language propositions, believing that philosophers should use the language of logic to address philosophical problems of ordinary language.
Carnap's approach, then, can be seen as a formalization of Frege's approach to definition.
Meaning postulates, for example, provide a format for stating and expressing relations between words. One question, however: How do you determine what to express in the meaning postulates?
Carnap holds that the intensionalist view is correct, and thus must show that there is an empirical procedure that can be applied to show these intensional relations. Toward this end, Carnap puts forth a test, which is to ask the informant about the application of the words horse and pferd. Do they apply, Carnap asks, to all actual cases? Do they apply to possible cases?
Meaning postulates should express generalizations about language based on speakers' linguistic behavior in what they apply to actual and possible cases. A common language?
Philosophy of Language Questions and Answers
The argument from "Two Dogmas" supplies the "missing" argument in the case for the inderminancy of translation. The argument plays a role in the indeterminacy thesis because Quine's reason for thinking that independent controls do not exist in translation takes its force from the argument that there are no linguistically neutral meanings. The absence of linguistically neutral meanings is a prerequiste for the indeterminacy of translation.
Pragmatic Accounts of Communication
Distinguishing Pragmatics from Semantics
Difficulties in Freeing Semantics from Pragmatics