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What is strict implication?

Published online by Cambridge University Press:  12 March 2014

Ian Hacking*
Affiliation:
Peterhouse, Cambridge

Extract

C. I. Lewis intended his systems S1–S5 as contributions to the study of “strict implication”, but in his formulation, strict implication is so thoroughly intertwined with other notions, such as possibility and negation, that it remains a problem, to separate out the properties of strict implication itself. I shall solve this problem for S2–5 and von Wright's M. The results for S3–5 are given below, while the implicative parts of S2 and M, which are rather more complicated, are given in §5.

In this presentation, ‘⊃’ stands for strict implication, and missing brackets for ‘⊃’ are restored by association to the right. A strict formula is one of the form A ⊃ B. Axiom schemes are used throughout.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1964

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References

[1]Ackermann, Wilhelm, Begründung einer strengen Implikation, this Journal, vol. 22 (1956). pp. 113128.Google Scholar
[2]Anderson, A. R., and Belnap, N. J., The pure calculus of entailment, this Journal, vol. 27 (1962), pp. 1952.Google Scholar
[3]Curry, Haskell B., A theory of formal deducibility, Notre Dame Mathematical Lectures No. 6 (1950).Google Scholar
[4]Curry, Haskell B., The definition of negation by a fixed proposition in the inferential calculus, this Journal, vol. 17 (1951), pp. 98104.Google Scholar
[5]Curry, Haskell B., The permutability of rules in the classical inferential calculus, this Journal, vol. 17 (1951), pp. 245248.Google Scholar
[6]Gentzen, G., Untersuchungen über das logische Schliessen, Mathematische Zeitschrift, vol. 39 (19341935), pp. 176210 and 405–431.CrossRefGoogle Scholar
[7]Kripke, Saul A., Distinguished constituents, this Journal, vol. 24 (1959), p. 323.Google Scholar
[8]Kripke, Saul A., The problem of entailment, this Journal, vol. 24 (1959), p. 324.Google Scholar
[9]Lewis, C. I., A survey of symbolic logic. University of California Press, 1918.CrossRefGoogle Scholar
[10]Lewis, C. I. and Langford, C. H., Symbolic logic. Century Company, New York, 1932.Google Scholar
[11]McKinsey, J. C. C. and Tarski, A., Some theorems about the sentential calculi of Lewis and Heyting, this Journal, vol. 13 (1948), pp. 115.Google Scholar
[12]Wright, G. H. von, An Essay in modal logic, North Holland Publishing Co., Amsterdam, 1951.Google Scholar