Skip to main content
Log in

Linear and unit-resulting refutations for Horn theories

  • Research Article
  • Published:
Journal of Automated Reasoning Aims and scope Submit manuscript

Abstract

We present a new transformation method by which a given Horn theory is transformed in such a way that resolution derivations can be carried out which are both linear (in the sense of Prologs SLD-resolution) and unit-resulting (i.e the resolvents are unit clauses). This is not trivial since although both strategies alone are complete, their naïve combination is not. Completeness is recovered by our method through a completion procedure in the spirit of Knuth-Bendix completion, however with different ordering criteria. A powerful redundancy criterion helps to find a finite system quite often.

The transformed theory can be used in combination with linear calculi such as e.g. (theory) model elimination to yield sound, complete and efficient calculi for full first order clause logic over the given Horn theory.

As an example application, our method discovers a generalization of the well-known linear paramodulation calculus for the combined theory of equality and strict orderings.

The method has been implemented and has been tested in conjunction with a model elimination theorem prover.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Astrachan, Owen L. and Stickel, Mark E.: Caching and lemmaizing in model elimination theorem provers, in D. Kapur (ed.), Proc. 11th Int. Conf. on Automated Deduction (CADE-11), LNAI 607, Springer-Verlag, 1992, pp. 224–238.

  • Bachmair, L. and Ganzinger, H.: On restrictions of ordered paramodulation with simplification, in M. E. Stickel (ed.), Proc. CADE-10, LNCS 449, Springer, 1990, pp. 427–441.

  • Bachmair, L. and Ganzinger, H.: Rewrite Techniques for Transitive Relations, Research Report MPI-I-93-249, Max-Planck-Institut für Informatik, 1993.

  • Bachmair, Leo, Dershowitz, Nachum, and Hsiang, Jieh.: Orderings for equational proofs, IEEE (1986), 346–357.

  • Bachmair, L., Dershowitz, N., and Plaisted, D.: Completion without failure, in H. Ait-Kaci and M. Nivat (eds), Resolution of Equations in Algebraic Structures 2: Rewrite Techniques, Academic Press, 1989, pp. 1–30.

  • Bachmair, L., Ganzinger, H., Lynch, C., and Snyder, W.: Basic paramodulation and superposition, in D. Kapur (ed.), Proc. 11th CADE, Springer, 1992, pp. 462–476.

  • Bachmair, L.: Proof Methods for Equational Theories, PhD Thesis, University of Illinois at Urbana, U.S.A., 1987.

  • Bachmair, L.: Canonical Equational Proofs, Progress in Theoretical Computer Science, Birkhäuser, 1991.

  • Baumgartner, P. and Furbach, U.: Consolution as a Framework for Comparing Calculi, J. Symbolic Computation 16(5) (1993).

  • Baumgartner, P. and Furbach, U.: Model elimination without contrapositives, in A. Bundy (ed.), Automated Deduction — CADE-12, LNAI 814, Springer, 1994, pp. 87–101.

  • Baumgartner, P. and Furbach, U.: PROTEIN: A PROver with a Theory Extension INterface, in A. Bundy (ed.), Automated Deduction — CADE-12, LNAI 814, Springer, 1994, pp. 769–773.

  • Baumgartner, P., Furbach, U., and Petermann, U.: A Unified Approach to Theory Reasoning, Research Report 15/92, University of Koblenz, 1992.

  • Baumgartner, P.: A model elimination calculus with built-in theories, in H.-J. Ohlbach (ed.), Proc. 16-th German AI-Conference (GWAI-92), LNAI 671, Springer, 1992, pp. 30–42.

  • Baumgartner, P.: An ordered theory resolution calculus, in A. Voronkov (ed.), Logic Programming and Automated Reasoning (Proceedings), St. Petersburg, Russia, July 1992, LNAI 624, Springer, pp. 119–130.

  • Baumgartner, P.: Refinements of theory model elimination and a variant without contrapositives, in A. G. Cohn (ed.), 11th European Conf. Artificial Intelligence, ECAI-94, Wiley, 1994, (Long version in: Research Report 8/93, University of Koblenz, Institute for Computer Science, Koblenz, Germany).

  • Bertling, H.: Knuth-Bendix completion of Horn clause programs for restricted linear resolution and paramodulation, in S. Kaplan and M. Okada (eds), Proc. 2nd Int. Workshop on Conditional and Typed Rewriting Systems, LNCS 516, Springer-Verlag, June 1990, pp. 181–193.

  • Bledsoe, W. W.: Challenge problems in elementary calculus, J. Automated Reasoning 6 (1990), 341–359.

    Article  Google Scholar 

  • Bollinger, T.: A model elimination calculus for generalized clauses, in IJCAI, 1991.

  • Bronsard, Francois and Reddy, Uday S.: Reduction techniques for first-order reasoning, in M. Rusinowitch and J. L. Rémy (eds), Proc. 3rd Int. Workshop on Conditional Term Rewriting Systems, LNCS 656, Springer-Verlag, 1992, pp. 242–256.

  • Bürckert, H.-J.: A Resolution Principle for Clauses with Restricted Quantifiers, LNAI 568, Springer, 1991.

  • Büttner, W.: Unification in the datastructure multisets, J. Automated Reasoning 2 (1986), 75–88.

    Article  Google Scholar 

  • Chang, C. and Lee, R.: Symbolic Logic and Mechanical Theorem Proving, Academic Press, 1973.

  • Dershowitz, N. and Manna, Z.: Proving termination with multiset orderings, Comm. ACM 22 (1979), 465–476.

    Article  MathSciNet  Google Scholar 

  • Dershowitz, N.: Orderings for term-rewriting systems, Theoretical Computer Science 17 (1982) 279–301.

    Article  MathSciNet  Google Scholar 

  • Dershowitz, N.: Computing with rewrite systems, Information and Control 65 (1985), 122–157.

    Article  MathSciNet  Google Scholar 

  • Dershowtiz, N.: Termination of rewriting, J. Symbolic Computation 3(1–2) (1987), 69–116.

    Google Scholar 

  • Dershowitz, N.: A maximal-literal unit strategy for Horn clauses, in S. Kaplan and M. Okada (eds), Proc. 2nd Int. Workshop on Conditional and Typed Rewriting Systems, LNCS 516, Springer-Verlag, June 1990, pp. 14–25.

  • Dershowitz, N.: Ordering-based strategies for Horn clauses, in Proc. IJCAI, 1991.

  • Dershowitz, N.: Canonical sets of Horn clauses, in J. Leach Albert, B. Monien, and M. Rodríguez Artalejo (eds), Proc. 18th Int. Colloquium on Automata, Languages and Programming, LNCS 510, 1991, pp. 267–278.

  • Digricoli, Vincent J. and Harrison, Malcolm C.: Equality-based binary resolution, J. Association for Computing Machinery, 1986.

  • Dixon, J.: Z-Resolution: Theorem-proving with compiled axioms, J. ACM 20(1) (1973), 127–147.

    Article  MathSciNet  Google Scholar 

  • Furbach, Ulrich, Hölldobler, Steffen, and Schreiber, Joachim: Horn equational theories and paramodulation. J. Automated Reasoning 3 (1989), 309–337.

    Article  Google Scholar 

  • Galler, J. H., Raatz, S., and Snyder, W.: Theorem proving using rigid e-unification: Equational matings, in Logics in Computer Science '87, Ithaca, New York, 1987.

  • Gallier, J., Narendran, P., Plaisted, D., and Snyder, W.: Rigid E-unification: NP-completeness and applications to equational matings, Information and Computation, 1990, pp. 129–195.

  • Ganzinger, Harald. A completion procedure for conditional equations, J. Symbolic Computation 11 (1991), 51–81.

    MathSciNet  Google Scholar 

  • Hines, L.: Str+ve⊂: The Str+ve-based subset prover, in M. Stickel (ed.), Proc. 10th Int. Conf. on Automated Deduction (CADE-10), LNAI 449, Springer-Verlag, 1990, pp. 193–206.

  • Hines, L.: The central variable strategy of Str+ve, in D. Kapur (ed.), Proc. 11th Int. Conf. on Automated Deduction (CADE-11), LNAI 607, Springer-Verlag, June 1992, pp. 35–49.

  • Hölldobler, S.: Foundations of Equational Logic Programming, Lecture Notes in Artificial Intelligence, 353, Subseries of Lecture Notes in Computer Science, Springer, 1989.

  • Hsiang, J. and Dershowitz, N.: Rewrite methods for clausal and non-clausal theorem proving, in Proc. ICALP'83, 1983.

  • Hsiang, J. and Rusinowitch, M.: On word problems in equational theories, in Proc. ICALP'87, LNCS 267, Springer, 1987, pp. 54–71.

  • Huet, Gérard and Oppen, Dereck C.: Equations and rewrite rules. A survey, in R. Book (ed.), Formal Languages: Perspectives and Open Problems, Academic Press, 1980, pp. 349–405.

  • Hullot, J. M.: Canonical forms and unification, in Proc. Conf. Automated Deduction, 1980, pp. 318–334.

  • Kaplan, Stéphane: Simplifying conditional term rewriting systems: Unification, termination and confluence, J. Symbolic Computation 4(3) (1987), 295–334.

    Google Scholar 

  • Knuth, Donald E. and Bendix, Peter, B.: Simple world problems in universal algebras, 1970.

  • Letz, R., Schumann, J., Bayerl, S., and Bibel, W.: SETHEO: A high-performance theorem prover, J. Automated Reasoning 8(2) (1992).

  • Letz, R., Mayr, K., and Goller, C.: Controlled integrations of the cut rule into connection tableau calculi, J. Automated Reasoning 1993, (to appear 1994).

  • Lloyd, J.: Foundations of Logic Programming, Springer, 1984.

  • Loveland, D.: Mechanical theorem proving by model elimination, JACM 15(2) (1968).

  • Loveland, D.: A linear format for resolution, in Symposium on Automatic Demonstration, Lecture Notes in Math. 125, 1970, pp. 147–162.

  • Loveland, D.: Automated Theorem Proving — A Logical Basis, North-Holland, 1978.

  • Manna, Z. and Waldinger, R.: Special relations in automated deduction, J. ACM 33(1) (1986), 1–59.

    Article  MathSciNet  Google Scholar 

  • Manna, Z., Stickel, M., and Stickel, R.: Monotonicity properties in automated deduction, in V. Lifschitz (ed.), Artificial Intelligence and Mathematical Theory of Computation: Essays in Honor of John McCarthy, Academic Press, 1991, pp. 261–280.

  • McCharen, J., Overbeek, R., and Wos, L.: Complexity and related enhancements for automated theorem-proving programs, Computers and Mathematics with Applications 2 (1976), 1–16.

    Article  Google Scholar 

  • Morris, J. B.: E-Resolution: An extension of resolution to include the equality relation, in Proc. IJCAI, 1969, pp. 287–294.

  • Murray, N. and Rosenthal, E.: Theory links: Applications to automated theorem proving. J. Symbolic Computation 4 (1987), 173–190.

    MathSciNet  Google Scholar 

  • Nieuwenhuis, R. and Orejas, F.: Clausal rewriting, in S. Kaplan and M. Okada (eds), Proc. 2nd Int. Workshop on Conditional and Typed Rewriting Systems, LNCS 516, Springer-Verlag, 1990, pp. 246–258.

  • Nieuwenhuis, R. and Rubio, A.: Theorem proving with ordering constrained clauses, in D. Kapur (ed.), Proc. 11th Int. Conf. on Automated Deduction (CADE-11), LNAI 607, Springer-Verlag, 1992, pp. 477–491.

  • Ohlbach, H.-J.: Compilation of recursive two-literal clauses into unification algorithms, in V. Sgurev Ph. Jorrand (ed.), Artificial Intelligence IV — Methodology, Systems, Applications, North-Holland, 1990.

  • Paul, E.: Equational methods in first order predicate calculus, J. Symbolic Computation 1(1) (1985).

  • Paul, E.: On solving the equality problem in theories defined by horn clauses, Theoretical Computer Science 44 (1986), 127–153.

    Article  MathSciNet  Google Scholar 

  • Petermann, U.: How to build in an open theory into connection calculi, J. Computers and Artificial Intelligence, 1991 (submitted).

  • Plaisted, D., Geoff Alexander, Heng Chu, and Shie-Jue Lee: Conditional Term Rewriting and First-Order Theorem Proving, 1993.

  • Plaisted, D.: A sequent-style model elimination strategy and a positive refinement, J. Automated Reasoning 4(6) (1990), 389–402.

    MathSciNet  Google Scholar 

  • Robinson, G. A. and Wos, L.: Paramodulation and theorem proving in first order theories with equality, in Meltzer and Mitchie (eds), Machine Intelligence 4, Edinburg University Press, 1969.

  • Siekmann, J. H.: Unification theory, J. Symbolic Computation 7(1) (1989), 207–274.

    MathSciNet  Google Scholar 

  • Steinbach, J.: Improving associative path orderings, in M. E. Stickel (ed.), Proc. CADE'10, LNCS 449, Springer, 1990, pp. 411–425.

  • Stickel, M. E.: Automated deduction by theory resolution, J. Automated Reasoning 1 (1985), 333–355.

    Article  MathSciNet  Google Scholar 

  • Stickel, M.: An introduction to automated deduction, in Bibel, Biermann, Delgrande, Huet, Jorrand, Shapiro, Mylopoulos, and Stickel (eds), Fundamentals of Artificial Intelligence, Springer, 1986, pp. 75–132.

  • Stickel, M. L.: A Prolog Technology Theorem Prover: A New Exposition and Implementation in Prolog, Technical Note 464, SRI International, 1989.

  • Stickel, M.: A prolog technology theorem prover, in M. E. Stickel (ed.), Proc. CADE' 10, LNCS 449, Springer, 1990, pp. 673–675.

  • Stickel, M.: Upside-Down Meta-Interpretation of the Model Elimination Theorem-Proving Procedure for Deduction and Abduction, 1991.

  • Stolzenburg, F. and Baumgartner, P.: Constraint Model Elimination and a PTTP-Implementation. Research Report 10/94, University of Koblenz, 1994.

  • Sutcliffe, G., Suttner, C., and Yemenis, T.: The TPTP problem library, in Proc. CADE-12, Springer, 1994.

  • Veroff, R. and Wos, L.: The linked inference principle, I: The formal treatment, J. Automated Reasoning 8(2) (1992).

  • Zhang, H. and Kapur, D.: First-order theorem proving using conditional rewrite rules, in R. Overbeek E. Lusk (ed.), Proc. 9th CADE, LNCS 310, Springer, 1988, pp. 1–20.

Download references

Author information

Authors and Affiliations

Authors

Additional information

This research was sponsored by the “Deutsche Forschungsgemeinschaft (DFG)“ within the “Schwerpunktprogramm Deduktion”.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Baumgartner, P. Linear and unit-resulting refutations for Horn theories. Journal of Automated Reasoning 16, 241–319 (1996). https://doi.org/10.1007/BF00252179

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00252179

Key words

Navigation