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