Introduction: Anyone who has studied anaphora has surely wondered why natural languages have so many types of expression which can be used anaphorically. Work in the philosophy of language on proper names and definite descriptions has not addressed this question, but linguists such as Prince (1981),Ariel (1988), and Gundel et al. (1993) have, hypothesizing a hierarchy of referential expressions correlating linguistic form to the level of salience of the entity referred to.1 One such Referential Hierarchy is provided below.