In "Fahrenheit 451" why does Montag want to read books?

Montag realizes that in his day, people are generally not happy. He knows that, in the past, people were happy. He tries to figure out what is different now and the main thing he can think of is that there used to be books and now there aren't any books. Also because in one of the chapters he watches the old lady burn with her books so if people are willing to die with their books than there has to be some sort of value and meaning to them.