Skolem functions and Hilbert’s ǫ-terms in Free Variable Tableau Systems
نویسندگان
چکیده
We apply the framework of the generic δ-rule presented in [4] to show how to map the δ-rule, which uses ǫ-terms as syntactical objects to expand existentially quantified formulae, in the context of standard δ-rules based on Skolem terms. Structural results coming out from such mapping process are discussed.
منابع مشابه
Hilbert’s ǫ-Terms in Automated Theorem Proving
ǫ-terms, introduced by David Hilbert [8], have the form ǫx.φ, where x is a variable and φ is a formula. Their syntactical structure is thus similar to that of a quantified formulae, but they are terms, denoting ‘an element for which φ holds, if there is any’. The topic of this paper is an investigation into the possibilities and limits of using ǫ-terms for automated theorem proving. We discuss ...
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