If you’re starting to learn about a field that you know nothing about, go to the children’s library and get some fifth, sixth, seventh grade books about it before you go into grownup books. Basic books for grownups tend to be aimed at college freshmen taking required courses—and everybody knows that they’re supposed to suffer, including the people who write the books. Basic books for kids are aimed at kids browsing in libraries who don’t have to be there and could leave anytime. The books have colors and pictures and a will to sell the subject; the good ones assume you know nothing without being condescending. You can get some vocabulary and feel for the shape of the subject before you