Bob is strong. Bob is big. Gary is short. Gary is small. Fiona is quiet. Dave is dull. Dave is sad. If someone is not huge then they are dull. If someone is not bad then they are kind. If someone is quiet then they are nice. If someone is nice and not rough then they are wealthy. If someone is dull and not huge then they are poor. If someone is short and small then they are rough. If someone is rough and not nice then they are sad. All kind people are smart. 
Dave is not smart.