论文信息 - Two Proof-Theoretic Remarks on EA + ECT

Two Proof-Theoretic Remarks on EA + ECT

In this note two propositions about the epistemic formalization of Church’s Thesis (ECT) are proved. First it is shown that all arithmetical sentences deducible in Shapiro’s system EA of Epistemic Arithmetic from ECT are derivable from Peano Arithmetic PA + uniform reflection for PA. Second it is shown that the system EA + ECT has the epistemic disjunction property and the epistemic numerical existence property for arithmetical formulas. Mathematics Subject Classification: 3F50.

Leon Horsten | Volker Halbach

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