An individual or individuals classified according to their age.
(=> (Age-Group ?Self)
(Exists (?A)
(And (Mereological-Member ?Self ?A)
(Physical-Person ?A)
(Exists (?B)
(And (Age ?A ?B) (Age-Value-Filler ?B)))
(Forall (?B ?C)
(=> (And (Age ?A ?B) (Age ?A ?C)) (= ?B ?C))))))