(<=> (Implication ?X) (Exists (?Plist) (And (List ?Plist) (>= (Length ?Plist) 2) (=> (Item ?P ?Plist) (Sentence ?P)) (= ?X (Cons (Quote =>) ?Plist)))))
(Exists (?Plist) (And (List ?Plist) (>= (Length ?Plist) 2) (=> (Item ?P ?Plist) (Sentence ?P)) (= ?X (Cons (Quote =>) ?Plist))))
(Exhaustive-Subclass-Partition Logsent (Setof Negation Conjunction Disjunction Implication Reverse-Implication Equivalence)) (<=> (Implication ?X) (Exists (?Plist) (And (List ?Plist) (>= (Length ?Plist) 2) (=> (Item ?P ?Plist) (Sentence ?P)) (= ?X (Cons (Quote =>) ?Plist)))))