Two Treatments of Definite Descriptions in Intuitionist Negative Free Logic
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Sentences containing definite descriptions, expressions of the form `The F', can be formalised using a binary quantifier ι that forms a formula out of two predicates, where ι x[F, G] is read as `The F is G'. This is an innovation over the usual formalisation of definite descriptions with a term forming operator. The present paper compares the two approaches. After a brief overview of the system 𝐈𝐍𝐅^ι of intuitionist negative free logic extended by such a quantifier, which was presented in <cit.>, 𝐈𝐍𝐅^ι is first compared to a system of Tennant's and an axiomatic treatment of a term forming ι operator within intuitionist negative free logic. Both systems are shown to be equivalent to the subsystem of 𝐈𝐍𝐅^ι in which the G of ι x[F, G] is restricted to identity. 𝐈𝐍𝐅^ι is then compared to an intuitionist version of a system of Lambert's which in addition to the term forming operator has an operator for predicate abstraction for indicating scope distinctions. The two systems will be shown to be equivalent through a translation between their respective languages. Advantages of the present approach over the alternatives are indicated in the discussion.
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