The distinction between 'partial ' and 'total ' interpretations (models) is discussed and related to the distinction between proof-theoretical and model-theoretical treatments of logic. It is claimed that there is a parallel between the construction of a proof based on a set of premises and e.g. the production of a natural-language text which is based on information in some kind of data-base. The main part of the paper is devoted to a discussion of the relations between the deduction rules traditionally associated with the existential quantifier and notions pertaining to the theory of reference such as specificity and referentiality / attributivity. Two types of spe-cificity are distinguished, which can be connected with...