Single Idea 13901

[catalogued under 4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / c. Derivations rules of PC]

Full Idea

In predicate calculus we take over the propositional connectives and propositional variables - but we need additional rules for handling quantifiers: four rules, an introduction and elimination rule for the universal and existential quantifiers.

Gist of Idea

Predicate logic uses propositional connectives and variables, plus new introduction and elimination rules


E.J. Lemmon (Beginning Logic [1965])

Book Reference

Lemmon,E.J.: 'Beginning Logic' [Nelson 1979], p.104

A Reaction

This is Lemmon's natural deduction approach (invented by Gentzen), which is largely built on introduction and elimination rules.