15-815 Automated Theorem Proving
Lecture 8: The Inverse Method
We then introduce 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.
The inverse method avoids backtracking, because we draw more and
more conclusions from our initial sequents, but can suffer from
space problems. Therefore techniques to reduce the number of
generated and retained sequents are critical for the efficiency
of the inverse method.