Maximum Cuts in Extended Natural Deduction
نویسندگان
چکیده
We consider a standard system of sequents and a system of extended natural deduction (which is a modification of natural deduction) for intuitionistic predicate logic and connect the special cuts, maximum cuts, from sequent derivations and maximum segments from derivations of extended natural deduction. We show that the image of a sequent derivation without maximum cuts is a derivation without maximum segments (i.e., a normal derivation) in extended natural deduction.
منابع مشابه
Normal Form Theorem for Systems of Sequents
In a system of sequents for intuitionistic predicate logic a theorem, which corresponds to Prawitz’s Normal Form Theorem for natural deduction, are proved. In sequent derivations a special kind of cuts, maximum cuts, are defined. Maximum cuts from sequent derivations are connected with maximum segments from natural deduction derivations, i.e., sequent derivations without maximum cuts correspond...
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