The novelist Henry Miller once observed that “a book is not only a friend, it makes friends for you.” If you’re sitting in a café, someone might strike up a conversation by asking about what you’re reading; a kindred spirit on the train might wave the same title that you’re holding; an office book club could lead to lasting friendships. Reading in public, far from being “performative,” instead marks you as belonging to a particular, enthusiastic society that recruits from all walks of life, in