Extracting Herbrand Disjunctions by Functional Interpretation
نویسندگان
چکیده
منابع مشابه
Extracting Herbrand disjunctions by functional interpretation
Carrying out a suggestion by Kreisel, we adapt Gödel’s functional interpretation to ordinary first-order predicate logic(PL) and thus devise an algorithm to extract Herbrand terms from PL-proofs. The extraction is carried out in an extension of PL to higher types. The algorithm consists of two main steps: first we extract a functional realizer, next we compute the β-normal-form of the realizer ...
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Herbrand disjunctions are a means for reducing the problem of whether a first-oder formula is valid in an open theory T or not to the problem whether an open formula, one of the so called Herbrand disjunctions, is T -valid or not. Nevertheless, the set of Herbrand disjunctions, which has to be examined, is undecidable in general. Fore this reason the practical value of Herbrand disjunctions has...
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ژورنال
عنوان ژورنال: BRICS Report Series
سال: 2003
ISSN: 1601-5355,0909-0878
DOI: 10.7146/brics.v10i32.21800