findSubsumed :: Concept -> [Concept] -> Maybe Concept
findSubsumed e@(Atomic cn) d = find (\x -> case x of Atomic cn2 | cn == cn2 -> True
                                                     And cs -> isJust $ findSubsumed e cs
                                                     _ -> False) d
findSubsumed :: Concept -> [Concept] -> Maybe Concept
findSubsumed e@(Atomic cn) d = find (\x -> case x of Atomic cn2 | cn == cn2 -> True
                                                     And cs -> isJust $ findSubsumed e cs
                                                     _ -> False) d
findSubsumed e@(Atomic cn) d = find (\x -> case x of Atomic cn2 | cn == cn2 -> True
                                                     And cs -> isJust $ findSubsumed e cs
                                                     _ -> False) d