 Another general issue, skeptically addressed in particular by Chomsky, is whether referential NPs even have as their semantic function to be used to refer to entities and thus whether referentialist semantics is even possible  (§2.2.5).  Not all approaches to natural language semantics in fact have as their aim giving truth conditions (whether such an aim is set aside or abandoned) and thus rely on referentialist semantics. Chomsky (2000) himself takes the view that the semantics of natural language can involve only our cognitive representation of the world and thus only another level of syntax, not entities and their properties themselves.