ABSTRACT
The step from languages of propositional logic to those of predicate logic consists in decomposing sentences into predicates and subjects (individual terms) and in the introduction of quantifiers as a new kind of logical constant. However, characterization of quantifiers in terms of inferential rules is much trickier than that of propositional operators; as a consequence, predicate logic is much more complex than the propositional one. In particular, whereas propositional operators can be seen as a means of “direct” regimentation of the elements of natural language, quantifiers do not have any such direct counterparts. Moreover, quantifiers go in tandem with variables, whose relationship to natural languages is even more obscure. The fact that it is, as a matter of principle, possible to articulate predicate logic wholly without the help of variables leads to the conclusion that variables are just artifacts of logical theory, that they are nothing that a logician discovers as (covertly) present in natural language but rather the logician’s expedients of giving an account for the language and its following-from.
