15-317 Constructive Logic
Lecture 11: Inversion
In this lecture we present two sequent calculi that are more
restricted than the one we have shown so far, and therefore much
better suited as the basis for a theorem prover. The first
eliminates the principal formula of an inference from the premises
as much as possible. The second eagerly applies invertible rules
eagerly to avoid unnecessary nondeterminism in search.