• Corpus ID: 208643529

Zermelo Fraenkel Set Theory in Higher-Order Logic

  title={Zermelo Fraenkel Set Theory in Higher-Order Logic},
  author={Lawrence Charles Paulson},
  journal={Arch. Formal Proofs},
This entry is a new formalisation of ZFC set theory in Isabelle/HOL. It is logically equivalent to Obua’s HOLZF [2]; the point is to have the closest possible integration with the rest of Isabelle/HOL, minimising the amount of new notations and exploiting type classes. There is a type V of sets and a function elts :: V ⇒ V set mapping a set to its elements. Classes simply have type V set, and the predicate small identifies those classes that correspond to actual sets. Type classes connected… 
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