proxy function

A function mapping objects of one domain onto objects of another. For instance, the device of Gödel numbering associates each formula of a system with a particular number. One radical way of defending the thesis of the inscrutability of reference is to argue that no evidence can determine whether a person is referring to an object, or to its image under a proxy function; instead of referring to a formula, a person might be interpreted equally well as referring to its Gödel number. If the sun is out, then one proxy function would be the relation ‘shadow of’, mapping a person onto his shadow; the inscrutability claim would be that we cannot tell whether an utterance such as ‘that person is tall’ means that the person is tall, or that the person's shadow is long.