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arXiv · 1712.00470

Notes on bounded induction for the compositional truth predicate

Mateusz Łełyk·Bartosz Wcisło
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Abstract

We prove that the theory of the extensional compositional truth predicate for the language of arithmetic with $Δ_0$-induction scheme for the truth predicate and the full arithmetical induction scheme is not conservative over Peano Arithmetic. In addition, we show that a slightly modified theory of truth actually proves the global reflection principle over the base theory.

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Mateusz Łełyk, Bartosz Wcisło. 2017-12-01. Notes on bounded induction for the compositional truth predicate. https://doi.org/10.1017/s1755020316000368

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