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