Conservativity for theories of compositional truth via cut elimination
نویسنده
چکیده
We present a cut elimination argument that witnesses the conservativity of the compositional axioms for truth (without the extended induction axiom) over any theory interpreting a weak subsystem of arithmetic. In doing so we also fix a critical error in Halbach’s original presentation. Our methods show that the admission of these axioms determines a hyper-exponential reduction in the size of derivations of truth-free statements.
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عنوان ژورنال:
- J. Symb. Log.
دوره 80 شماره
صفحات -
تاریخ انتشار 2015