15-815 Automated Theorem Proving
Lecture 14: Horn Logic
In this lecture we introduce Horn logic. Horn logic has several
remarkable properties. For example, both intuitionistic and classical
provability coincide for Horn theories. Moreover, Horn theories
can be viewed as inductively defined, and Horn clauses can be
translated to inference rules.
We use Horn logic to define backward and forward chaining.
Backward chaining is a counterpart to the strategy of eagerly
applying inversion rules by limiting the number of choices
we consider drastically.