Heaps and gluts: Paraconsistent logic applied to vagueness

Joanna Odrowąż-Sypniewska

DOI: http://dx.doi.org/10.12775/LLP.1999.015


This paper is an attempt to show that the subvaluation theory is not a good theory of vagueness. It begins with a short review of supervaluation and subvaluation theories and procedes to evaluate the subvaluation theory. Subvaluationism shares all the main short-comings of supervaluationism. Moreover, the solution to the sorites paradox proposed by subvaluationists is not satisfactory. There is another solution which subvaluationists could avail themselves of, but it destroys the whole motivation for using a paraconsistent logic and is not different from the one offered by supervaluationism.

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Dummett, M., “Wang’s Paradox”, Synthese 30 (1975), 301–324.

Edgington, D., “Wright and Sainsbury on Higher-order Vagueness”, Analysis 53 (1993), 193–200.

Fine, K., “Vagueness, Truth and Logic”, Synthese 30 (1975), 265–300.

Hyde, D., “From Heaps and Gaps to heaps of Gluts”, Mind 106 (1997), 641–660.

Hyde, D., “Proliferating Conceptions of Truth: Comments on McGee and McLaughlin”, in T. Horgan (ed.), Vagueness. The Southern Journal of Philosophy 1994, pp. 253–262.

Jaśkowski, S., “Propositional Calculus for Contradictory Deductive Systems”, Studia Logica 24 (1969), 143–157.

Priest, G., R. Routley, Paraconsistent Logic. Essays on the Inconsistent, Philosophia Verlag, Monachium 1989.

Sainsbury, R.M., Paradoxes, Cambridge University Press, Cambridge 1995.

Sainsbury, R.M., T. Williamson, “Sorites”, in B. Hale, C. Wright (eds.), A Companion to the Philosophy of Language, Basil Blackwell, London 1997.

Tye, M., “Supervaluationism and the Law of Excluded Middle”, Analysis 49 (1990), 141–143.

Williamson, T., Vagueness, Routledge, London and New York 1994.

ISSN: 1425-3305 (print version)

ISSN: 2300-9802 (electronic version)

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