There used to be a used bookstore near where I lived (McIntyre and Moore in Davis Square in Somerville). They had a sign on the wall about the kind of books th

There used to be a used bookstore near where I lived (McIntyre and Moore in Davis Square in Somerville). They had a sign on the wall about the kind of books they wanted to buy. They wanted books in fields where it is hard to make a living. I always thought that was an interesting heuristic. I guess that's where the passion is.