A thin person is a weakling who needs to read books on how to get their body fat and strong again.
Imagine you're weakling loser who doesn't go out too much, has no friends and never had any interest in sports or fitness, but suddenly you want to get fit so that the girl you fell in love with likes you back. What do you do? Obviously you need to read a few fitness books on how to build up your body and get that sexy six-pack!