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