Dave is strong. Dave is high. Gary is small. Gary is little. Alan is nice. Harry is bad. Harry is dull. If someone is not big then they are bad. If someone is not poor then they are quiet. If someone is nice then they are kind. If someone is kind and not rough then they are wealthy. If someone is bad and not big then they are sad. If someone is small and little then they are rough. If someone is rough and not kind then they are dull. All quiet people are smart. 
Gary is not dull.