Dave is high. Dave is strong. Alan is small. Alan is thin. Anne is clever. Harry is dull. Harry is rough. If someone is not huge then they are dull. If someone is not poor then they are wealthy. If someone is clever then they are nice. If someone is nice and not bad then they are kind. If someone is dull and not huge then they are sad. All sad people are short. If someone is small and thin then they are bad. If someone is bad and not nice then they are rough. If someone is rough then they are young. If someone is wealthy then they are smart. All smart people are quiet. All kind people are experienced. 
Alan is young.