Dave is high. Dave is strong. Charlie is small. Charlie is thin. Bob is wealthy. Alan is dull. Alan is rough. If someone is not big then they are dull. If someone is not bad then they are clever. If someone is wealthy then they are nice. If someone is nice and not poor then they are quiet. If someone is dull and not big then they are sad. All sad people are tiny. If someone is small and thin then they are poor. If someone is poor and not nice then they are rough. If someone is rough then they are young. If someone is clever then they are kind. All kind people are smart. All quiet people are experienced. 
Alan is smart.