Full Idea
Proper names pose a problem for the "use" theorist. Try stating a rule of use for the name 'William G. Lycan'.
Gist of Idea
It is hard to state a rule of use for a proper name
Source
William Lycan (Philosophy of Language [2000], Ch. 6)
Book Reference
Lycan,William G.: 'Philosophy of Language' [Routledge 2000], p.94
A Reaction
Presumably it is normally used in connection with a particular human being, and is typically the subject of a grammatical sentence. Any piece of language could also be used to, say, attract someone's attention.