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ABSTRACT
A generalization of the resolution method for higher order logic is presented. The languages acceptable for the method are phrased in a theory of types of order w (all finite types)—including the &lgr;-operator, propositional functors, and quantifiers. The resolution method is, of course, a machine-oriented theorem search procedure based on refutation. In order to make this method suitable for higher order logic, it was necessary to overcome two sorts of difficulties. The first is that the unifying substitution procedure—an essential feature of the classic first-order resolution—must be generalized (it is noted that for the higher order unification the proper notion of substitution will include &lgr;-normalization). A general unification algorithm is produced and proved to be complete for second-order languages. The second difficulty arises because in higher order languages, semantic intent is essentially more “interwoven” in formulas than in first-order languages. Whereas quantifiers could be eliminated immediately in first-order resolution, their elimination must be deferred in the higher order case. The generalized resolution procedure which the author produces thus incorporates quantifier elimination along with the familiar features of unification and tautological reduction. It is established that the author's generalized resolution procedure is complete with respect to a natural notion of validity based on Henkin's general validity for type theory. Finally, there are presented examples of the application of the method to number theory and set theory.
REFERENCES
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1
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ANDREWS, P. Resolution in type theory. J. Symbolic Logic $6, 3 (1971), 414-432.
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2
|
BLEDSOE, W.W. Splitting and reduction heuristics in automatic theorem proving. Artificial Intelligence ~ (1971), pp. 57-78.
|
| |
3
|
VE BRUIJN, N.G. The mathematical language AUTOMATH, its usage and some of its extensions. Symposium on Automatic Demonstration, Versailles, Dec. 1968, Springer- Verlag, 1970, pp. 29-61.
|
| |
4
|
CHURCH, A. The Calculi of Lambda-Conversion. Princeton U. Press, Princeton, N. J., 1941.
|
| |
5
|
DARLXNGTON, J.L. Automatic theorem proving with equality substitutions and mathematical induction. In Machine Intelligence 3, D. Michie (Ed.), American Elsevier, New York, 1968, pp. 113-130.
|
| |
6
|
DARLINGTON, J.L. A partial mechanization of second-order logic. In Machine Intelligence 6, B. Melzer and D. Michie (eds.), American Elsevier, New York, 1971, pp. 91-100.
|
| |
7
|
GOULD, W.E. A matching procedure for omega-order logic. Ph.D. thesis, Princeton U., Princeton, N. J.; University Microfilms, Ann Arbor, Mich.
|
| |
8
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HENKIN, L. Completeness in the theory of types. J. Symbolic Logic 15 (1960), 81-91.
|
| |
9
|
JENSEN, D. C. A two-valued type theory model convenient for resolution theoremproving. CSRR 2055, Dep. of Applied Analysis and Comput. Sci., U. of Waterloo, Waterloo, Ont., Canada, 1971.
|
| |
10
|
MELTZER, B. Power amplification for theorem-provers. In Machine Intelligence 5, B. Meltzer and D. Michie (Eds.), American Elsevier, New York, 1970, pp. 165-180.
|
| |
11
|
MONK, J. D. Introduction to Set Theory. McGraw-Hill, New York, 1969.
|
| |
12
|
PIETaZYKOWSKI, T. A natural language for formal mathematical reasoning (TPL 2), Part I. CSRR 2015, Dep. of Applied Analysis and Comput. Sci., U. of Waterloo, Waterloo, Ont., Canada, 1970.
|
| |
13
|
PIETRZYKOWSKI, T. A complete mechanization of second order skolemized logic. CSRR 2036, Dep. of Applied Analysis and Comput. Sci., U. of Waterloo, Waterloo, Ont., Canada, 1971.
|
 |
14
|
|
| |
15
|
ROBINSON, J.A. New directions in mechanical theorem proving. Proe. IFIP Cong. 68, Vol. 1, North-Holland Pub. Co., Amsterdam, pp. 63-67.
|
| |
16
|
ROmNSON, J.A. Mechanizing higher-order logic. In Machine intelligence ~, B. Meltzer and D. Michie (Eds.), American Elsevier, New York, 1969, pp. 157-172.
|
| |
17
|
SHOENFIEm), J. R. Mathematical Logic, Addison-Wesley, Reading, Mass., 1967.
|
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