const In : set set prop term iIn = In infix iIn 2000 2000 term Subq = \x:set.\y:set.!z:set.z iIn x -> z iIn y const Sep : set (set prop) set axiom SepE1: !x:set.!p:set prop.!y:set.y iIn Sep x p -> y iIn x claim !x:set.!p:set prop.Subq (Sep x \y:set.p y) x