Relation ELEMENT-OF

A specialized common sense notion of part for uniform parts of collections. Quasi-synonyms: item, member.
Arity: 2
Subrelation-Of: Part-of
Axioms:
(=> (Element-Of ?A ?B)
    (And (_Collection ?B True)
         (Forall (?W ?Z)
                 (=> (And (Element-Of ?W ?B) (Element-Of ?Z ?B))
                     (Equal-But-Localization ?W ?Z)))))