15-815 Automated Theorem Proving
Lecture 22: Indexing
We postpone further discussion of equality in order to introduce
techniques for subsumption. Subsumption is extremely important in
saturation based theorem provers in order to control the size
of the data base of derived clauses (= sequents, in the intuitionistic
We present two basic techniques: discrimination trees (most suitable
for unit forward subsumption) and path indexing (most suitable for
backward subsumption). We also presents Tammet's hierarchical filters
which provide an additional technique to perform subsumption checking.
Towards Efficient Subsumption.
Proceedings of the 15th International Conference on Automated Deduction, C.Kircher and H.Kirchner, eds., pp.427-441, Springer-Verlag LNAI 1421,
I.V. Ramakrishnan, R. Sekar, and Andrei Voronkov.
Handbook of Automated Reasoning, Vol.2, pp 1853-1965, Elsevier
Science and MIT Press, 2001.