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WEAKLY CLASSICAL THEORIES OF IDENTITY

Published online by Cambridge University Press:  26 October 2011

JOSHUA SCHECHTER*
Affiliation:
Department of Philosophy, Brown University
*
*DEPARTMENT OF PHILOSOPHY, BROWN UNIVERSITY, BOX 1918, PROVIDENCE, RI 02912 E-mail: [email protected]

Abstract

There are well-known quasi-formal arguments that identity is a “strict” relation in at least the following three senses: (1) There is a single identity relation and a single distinctness relation; (2) There are no contingent cases of identity or distinctness; and (3) There are no vague or indeterminate cases of identity or distinctness. However, the situation is less clear cut than it at first may appear. There is a natural formal theory of identity that is very close to the standard classical theory but which does not validate the formal analogues of (1)–(3). The core idea is simple: We weaken the Principle of the Indiscernibility of Identicals from a conditional to an entailment and we adopt a weakly classical logic. This paper investigates this weakly classical theory of identity (and related theories) and discusses its philosophical ramifications. It argues that we can accept a reasonable theory of identity without committing ourselves to the uniqueness, necessity, or determinacy of identity.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2011

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References

BIBLIOGRAPHY

Akiba, K. (2004). Vagueness in the world. Noûs, 38(3), 407429.CrossRefGoogle Scholar
Barcan, R. (1947). The identity of individuals in a strict functional calculus of second order. The Journal of Symbolic Logic, 12(1), 1215.CrossRefGoogle Scholar
Barnes, E. (2009). Indeterminacy, identity and counterparts: Evans reconsidered. Synthese, 108(1), 8196.CrossRefGoogle Scholar
Belnap, N. D. (1962). Tonk, plonk and plink. Analysis, 22(6), 130134.CrossRefGoogle Scholar
Evans, G. (1978). Can there be vague objects? Analysis, 38(4), 208.CrossRefGoogle Scholar
Field, H. (2008). Saving Truth from Paradox. Oxford, UK: Oxford University Press.CrossRefGoogle Scholar
Fine, K. (1975). Vagueness, truth and logic. Synthese, 30(3–4), 265300.CrossRefGoogle Scholar
Gentzen, G. (1934/1935). Untersuchungen über das logische schließen. Mathematische Zeitschrift, 39, 176210, 405–431.CrossRefGoogle Scholar
Harman, G. (1995). Rationality. In Smith, E., and Osherson, D., editors. Thinking: An Invitation to Cognitive Science (second edition). Cambridge, MA: The MIT Press, pp. 175211.Google Scholar
Heck, R. (1998). That there might be vague objects (so far as concerns logic). The Monist, 81(2), 274296.CrossRefGoogle Scholar
Hughes, G. E., & Cresswell, M. J. (1996). A New Introduction to Modal Logic. New York, NY: Routledge.CrossRefGoogle Scholar
Kripke, S. (1971). Identity and necessity. In Munitz, M., editor. Identity and Individuation. New York, NY: New York University Press, pp. 135164.Google Scholar
Lewis, D. (1986). On the Plurality of Worlds. Oxford, UK: Wiley-Blackwell.Google Scholar
Lewis, D. (1988). Vague identity: Evans misunderstood. Analysis, 48(3), 128130.CrossRefGoogle Scholar
McGee, V., & McLaughlin, B. P. (2004). Logical commitment and semantic indeter- minacy: A reply to Williamson. Linguistics and Philosophy, 27(1), 123136.CrossRefGoogle Scholar
Putnam, H. (1983). Vagueness and alternative logic. Erkenntnis, 19, 297314.CrossRefGoogle Scholar
Quine, W. V. O. (1961). Reply to Professor Marcus. Synthese, 13(4), 323330.CrossRefGoogle Scholar
Rasiowa, H., & Sikorski, R. (1970). The Mathematics of Metamathematics (third edition). Warsaw, Poland: Polish Scientific Publishers.Google Scholar
Salmon, N. (1981). Reference and Essence. Princeton, NJ: Princeton University Press.Google Scholar
Schechter, J. (2011). Juxtaposition: A new way to combine logics. The Review of Symbolic Logic.CrossRefGoogle Scholar
Williams, J. R. G. (2008). Multiple actualities and ontically vague identity. The Philosophical Quarterly, 58(230), 134154.Google Scholar
Williamson, T. (1994). Vagueness. New York, NY: Routledge.Google Scholar
Williamson, T. (2007). Absolute identity and absolute generality. In Rayo, A., and Uzquiano, G., editors. Absolute Generality. Oxford, UK: Oxford University Press, pp. 369390.Google Scholar
Wright, C. (2001). On being in a quandry: Relativism, vagueness, logical revisionism. Mind, 110, 4598.CrossRefGoogle Scholar