Proofs, what they prove and their representations: remarks in connection with identity of proofs and the normalisation thesis

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Tiago de Castro Alves

Abstract

A topic of de Castro Alves (2019) stands in need of re-visitation, namely: possible ways of specifying restrictions on the notion of proof and some other related ones that are relevant in connection with the discussion on identity of proofs. This effort is dedicated to start a compensation for relevant shortcomings of some ideas proposed in that work. More concretely: by taking some very generic traits of proofs as a departure point, we proceed to the identification of possible outset conditions upon the investigation of identity of proofs (instead of proposing a taxonomy of criteria of identity of proofs, as in de Castro Alves (2019)). We will describe and briefly comment on two kinds of such conditions: one given in terms of how the identity of proofs is conditioned by the identity of what is proved, and other in terms of how equivalence relations between proof (re)presentations are conditioned by, on the one hand, how many distinct (collections/kinds of) proofs can be (re)presented by them, and, on the other, how many distinct (re)presentations a collection of proofs may have. To exemplify the meaningfulness of these considerations, they will be used here as basis for some critical remarks on the normalisation thesis on identity of proofs.

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Author Biography

Tiago de Castro Alves, Universidade Estadual de Campinas (UNICAMP)

Possui graduação em Filosofia pela Universidade do Estado do Rio de Janeiro (2010), mestrado em Filosofia pela Pontifícia Universidade Católica do Rio de Janeiro (2013) e doutorado em Filosofia - University of Tübingen (2018). Atualmente é pesquisador de pós-doutorado na Unicamp. Tem experiência na área de Filosofia, com ênfase em Lógica, atuando principalmente nos seguintes temas: identidade de provas, sinonímia, normalização, hipóteses, ilocuções em provas.

References

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