Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-30T21:11:41.125Z Has data issue: false hasContentIssue false

Logic of many-sorted theories

Published online by Cambridge University Press:  12 March 2014

Extract

Certain axiomatic systems involve more than one category of fundamental objects; for example, points, lines, and planes in geometry; individuals, classes of individuals, etc. in the theory of types or in predicate calculi of orders higher than one. It is natural to use variables of different kinds with their ranges respectively restricted to different categories of objects, and to assume as substructure the usual quantification theory (the restricted predicate calculus) for each of the various kinds of variables together with the usual theory of truth functions for the formulas of the system. An axiomatic theory set up in this manner will be called many-sorted. We shall refer to the theory of truth functions and quantifiers in it as its (many-sorted) elementary logic, and call the primitive symbols and axioms (including axiom schemata) the proper primitive symbols and proper axioms of the system. Our purpose in this paper is to investigate the many-sorted systems and their elementary logics.

Among the proper primitive symbols of a many-sorted system Tn (n = 2, …, ω) there may be included symbols of some or all of the following kinds: (1) predicates denoting the properties and relations treated in the system; (2) functors denoting the functions treated in the system; (3) constant names for certain objects of the system. We may either take as primitive or define a predicate denoting the identity relation in Tn.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1952

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Schmidt, Arnold, Über deduktive Theorien mit mehreren Sorten von Grunddingen, Mathematische Annalen, vol. 115 (1938), pp. 485506.CrossRefGoogle Scholar
[2]Langford, C. H., Review of [1], this Journal, vol. 4 (1939), p. 98.Google Scholar
[3]Quine, W. V., Mathematical logic, 2nd printing, Cambridge 1947.Google Scholar
[4]Hilbert, D. and Bernays, P., Grundlagen der Mathematik, vol. 1, Berlin 1934; vol. 2, Berlin 1939.Google Scholar
[5]Herbrand, Jacques, Recherches sur la théorie de la démonstration, Dissertation, Paris 1930.Google Scholar
[6]Church, Alonzo, Introduction to mathematical logic, Princeton 1944.Google Scholar
[7]Gödel, Kurt, Die Vollständigkeit der Axiome des logischen Funklionenkalküls, Monatshefte für Mathematik und Physik, vol. 37 (1930), pp. 349360.CrossRefGoogle Scholar
[8]Wang, Hao, Existence of classes and value specification of variables, this Journal, vol. 15 (1950), pp. 103112.Google Scholar
[9]Gödel, Kurt, Über formal unentscheidbare Sätze der Principia Mathematica und verwandter Systeme I, Monatshefte für Mathematik und Physik, vol. 38 (1931), pp. 173198.Google Scholar