Abstract
What is the appropriate notion of truth for sentences whose meanings are understood in epistemic terms such as proof or ground for an assertion? It seems that the truth of such sentences has to be identified with the existence of proofs or grounds, and the main issue is whether this existence is to be understood in a temporal sense as meaning that we have actually found a proof or a ground, or if it could be taken in an abstract, tenseless sense. Would the latter alternative amount to realism with respect to proofs or grounds in a way that would be contrary to the supposedly anti-realistic standpoint underlying the epistemic understanding of linguistic expressions? Before discussing this question, I shall consider reasons for construing linguistic meaning epistemically and relations between such reasons and reasons for taking an anti-realist point of view towards the discourse in question.
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Notes
It is somewhat inappropriate to say that we assert the conclusion or a premiss of an inference, since the premisses and the conclusion are assertions (or judgements). This way of speaking is nevertheless often convenient and is used here; it is even appropriate if we think of the premisses and conclusion as represented by sentences.
Prawitz (1995).
Per Martin-Löf (1998) has drawn the conclusion that it is not. He and Göran Sundholm (1998) indicate this by referring to proofs so conceived as “proof-objects”, where proof-objects are just truth-makers in terms of which the meaning of propositions is explained, much like in realist theories of meaning.
Doubts concerning this have been expressed for instance by Peter Pagin (2009). As argued by Williamson (2003), one has to beware of identifying a person's implicit knowledge of the meaning of a sentence with her actual use of an inference rule or of a form of argument or proof; the knowledge is rather a question of knowing the rule or knowing what counts as a valid argument or proof in the language in question, as pointed out by Cozzo (2008).
Dummett (1987, 286) says that he is happy for any outcome of the investigation: if it supports realism, "we shall have discovered the true justification of realism".
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Acknowledgments
I am grateful to professor Cesare Cozzo for constructive comments after his reading of an earlier version of the paper.
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Prawitz, D. Truth as an Epistemic Notion. Topoi 31, 9–16 (2012). https://doi.org/10.1007/s11245-011-9107-6
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DOI: https://doi.org/10.1007/s11245-011-9107-6