15-815 Automated Theorem Proving
Lecture 7: Interpreting Classical in Intuitionistic Logic
We given an interpretation of classical in intuitionistic logic and
prove that it is sound and complete. This means that we can use a
theorem prover for intuitionistic logic to solve problems in classical
logic, although this is hardly a recommended approach since
intuitionistic logic is more expressive than classical logic.
We then begin discussion of the inverse method as an alternative
approach to proof search. The inverse method is based on a sequent
calculus designed for forward reasoning (from the initial sequents to
the conclusion) combined with the observation that we only ever need to
introduce subformula of our proposed theorem during proof search.