What is this thing called dialetheism?
DOI:
https://doi.org/10.5007/1808-1711.2025.e107886Keywords:
Contradictions, Negations, Paraconsistency, DialetheismAbstract
This paper has two parts. In the first I discuss two claims made by Priest in Some Comments and Replies (DOI: 10.1007/978-3-030-25365-3 27, 2019): (i) that the idea of ‘contradictions in reality’ lacks textual support in his work, and (ii) that such contradictions would require a theory of truth as correspondence with entities such as facts or states of affairs. With respect to (i), I will recognize that, after a closer reading of his texts, in particular In Contradiction (2nd edition, OUP, 2006), I have not been able to find clear examples of dialetheias related to real contradictions. As far as I could see, for Priest, dialetheism is mainly a thesis about our conceptual framework and mental processes. As for (ii), in opposition to him, I will argue that all we need to make sense of the idea of contradictions in reality is the apparatus provided by Tarski’s definition of truth, and an object a and a predicate P such that a satisfies both P and ¬P. In the second part, I discuss what one must accept to be a dialetheist and what is required for dialetheism to be a plausible and interesting thesis. My conclusion is that dialetheism ends up being either a strong but implausible thesis about contradictions in extra-mental and extra-linguistic phenomena, or a weaker but interesting claim about contradictions produced by thought and language.
References
Antunes, H. 2019. Contradictions for Free: Towards a Nominalistic Interpretation of Contradictory Theories. PhD thesis, University of Campinas.
Antunes, H.; Rodrigues, A.; Carnielli, W.; Coniglio, M. E. 2022. Valuation semantics for first-order logics of evidence and truth. Journal of Philosophical Logic 51: 1141--1173.
Aristotle. 1996. The Complete Works of Aristotle. Oxford University Press.
Armstrong, D. M. 2004. Truth and Truthmakers. Cambridge University Press.
Azzouni, J. 2004. Deflating Existential Consequence: A Case for Nominalism. Oxford University Press.
Batens, D. 2002. In defence of a programme for handling inconsistencies. In: J. Meheus (ed) Inconsistency in Science. Dordrecht: Springer.
Belnap, N. D. 1977. How a computer should think. In: G. Ryle (ed.) Contemporary Aspects of Philosophy. Oriel Press.
Cardoso, G.; Rodrigues, A. 2019. A definição de verdade de Tarski. Enunciação 4. {http://www.editorappgfilufrrj.org/enunciacao/index.php/revista/article/view/76.
Carnielli, W.; Rodrigues, A. 2017. An epistemic approach to paraconsistency: a logic of evidence and truth. Synthese 196: 3789--3813.
Carnielli, W.; Rodrigues, A. 2019. Inferential semantics, paraconsistency and preservation of evidence. In: Graham Priest on Dialetheism and Paraconsistency. Springer.
Carnielli, W.; Rodrigues, A. 2020. On epistemic and ontological interpretations of intuitionistic and paraconsistent paradigms. Logic Journal of the IGPL 29: 569--584.
Carnielli, W.; Coniglio, M.; Podiacki, R.; Rodrigues, T. 2014. On the way to a wider model theory: Completeness theorems for first-order logics of formal inconsistency. The Review of Symbolic Logic 7.
Coniglio, M.; Rodrigues, A. 2024. From Belnap-Dunn four-valued logic to six-valued logics of evidence and truth. Studia Logica 112: 561--606.
da Costa, N. C. A; French, S. 2003. Science and Partial Truth. Oxford University Press.
da Costa, N. C. A.; Krause, D.; Bueno, O. 2007. Paraconsistent logics and paraconsistency. In: D. Jacquette et al., (eds) Philosophy of Logic --- Handbook of the Philosophy of Science Vol. 5. Elsevier.
Dunn, J. M. 1976. Semantics for first-degree entailments and `coupled trees'. Philosophical Studies 29(3): 149--168.
Dunn, J. M. 2019. Two, three, four, infinity: The path to the four-valued logic and beyond. In: H. Omori; H. Wansing (eds) New Essays on Belnap-Dunn Logic, pp.77--97. Springer.
Dunn, J. M.; Kiefer, N. M. 2019. Contradictory information: Better than nothing? The paradox of the two firefighters. In: C. Başkent; T. M. Ferguson (eds) Graham Priest on Dialetheism and Paraconsistency. Springer.
Dunn, J. M. 2000. Partiality and its dual. Studia Logica: 5--40.
Frápolli, M. 1996. Review of Graham Priest, Beyond the limits of thought. The Review of Modern Logic 6(4): 437--439.
Frege, G. 1984. Function and concept. In B. McGuinness (ed) Frege: Collected Papers on Mathematics, Logic, and Philosophy. Basil Blackwell.
Frege, 1984. On concept and object. In B. McGuinness (ed) Frege: Collected Papers on Mathematics, Logic, and Philosophy. Basil Blackwell.
Garfield, J. 2004. `To pee and not to pee?' Could that be the question? (Further reflections of the dog). In: G. Priest; Jc Beall; B. Armour-Garb (eds) The Law of Non-Contradiction: New Philosophical Essays. Oxford University Press.
Gottlieb, P. 2019. Aristotle on non-contradiction. In: E. N. Zalta (ed) The Stanford Encyclopedia of Philosophy. Spring 2019 edition.
Heck, R. 2023. Tarski's theory of truth. Accessed 21/8/2023. {https://rkheck.frege.org/philosophy/pdf/notes/TarskisTheoryOfTruth.pdf.
Kolár, P. 1999. Truth, correspondence, satisfaction. In: J. Peregrin (ed) Truth and its Nature (if any). Dordrecht: Kluwer.
Lukasiewicz, J. 1971. On the principle of contradiction in Aristotle. The Review of Metaphysics 24: 485--509.
Mares, E. 2004. Semantic dialetheism. In: G. Priest; Jc Beall; B. Armour-Garb (eds) The Law of Non-Contradiction: New Philosophical Essays. Oxford University Press.
Meheus, J. 2002. Preface. In: J. Meheus (ed) Inconsistency in Science. Dordrecht: Springer.
Merricks, T. 2007. Truth and Ontology. Oxford University Press.
Mulligan, K.; Simons, P.; Smith, B. 1984. Truth-Makers. Philosophy and Phenomenological Research 44: 287--321.
Odintsov, S.; Wansing, H. 2016. On the methodology of paraconsistent logic. In: H. Andreas; P. Verdée (eds) Logical Studies of Paraconsistent Reasoning in Science and Mathematics. Springer.
Omori, H.; Wansing, H. (eds.). 2019. New Essays on Belnap-Dunn Logic --- Synthese Library Studies in Epistemology, Logic, Methodology, and Philosophy of Science, Volume 418. Springer.
Popper, K. 1972. Objective Knowledge. Oxford: Clarendon Press.
Priest, G. 2006a. In Contradiction: A Study of the Transconsistent. 2nd Edition. Oxford University Press, 1987.
Priest, G. 2006b. Doubt Truth to be a Liar. Oxford University Press.
Priest, G. 2008. Graham Priest and Diderik Batens interview each other. The Reasoner 8(2): 2--4.
Priest, G. 2019a. Some comments and replies. In: C. Başkent; T. M. Ferguson (eds) Graham Priest on Dialetheism and Paraconsistency. Springer.
Priest, G. 2019b. It was so revolting I couldn't take my eyes off it. In: A. Rieger; G. Young (eds) Dialetheism and its Applications (Trends in Logic Vol. 52). Springer.
Priest, G.; Berto, F.; Weber, Z. 2018. Dialetheism. The Stanford Encyclopedia of Philosophy (Fall 2018 Edition).
Read, S. 2000. Truthmakers and the disjunction thesis. Mind 109: 67--79.
Rodrigues, A.; Antunes, H. 2022. First-order logics of evidence and truth with constant and variable domains. Logica Universalis 16: 419--449.
Rodrigues, A.; Carnielli, W. 2022. On Barrio, Lo Guercio, and Szmuc on logics of evidence and truth. Logic and Logical Philosophy 31: 313--338.
Rodrigues, A.; Bueno-Soler, J.; Carnielli, W. 2020. Measuring evidence: a probabilistic approach to an extension of Belnap-Dunn Logic. Synthese 198: 5451--5480.
Rodriguez-Pereyra, G. Why truthmakers. In H. Beebee; J. Dodd (eds) Truthmakers: the contemporary debate. Oxford University Press.
Russell, B. 2010. The Philosophy of Logical Atomism. Routledge.
Sher, G. 1999a. On the possibility of a substantive theory of truth. Synthese 117: 133--172.
Sher, G. 1999b. What is Tarski's theory of truth? Topoi 18: 149--166.
Steinberger, F. 2016. Explosion and the normativity of logic. Mind 125(498): 385--419.
Tarski, A. 1956a. The concept of truth in formalized languages. In: Logic, Semantics, Metamathematics. Clarendon Press.
Tarski, A. 1956b. The establishment of scientific semantics. In: Logic, Semantics, Metamathematics. Clarendon Press.
Tarski, A. 1944. The semantic conception of truth and the foundations of semantics. Philosophy and Phenomenological Research 4: 341--376.
Downloads
Published
Issue
Section
License
Copyright (c) 2025 Abilio Rodrigues
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Principia http://www.periodicos.ufsc.br/index.php/principia/index is licenced under a Creative Commons - Atribuição-Uso Não-Comercial-Não a obras derivadas 3.0 Unported.
Base available in www.periodicos.ufsc.br.
