Today is the Day of the Book, in part spurred by the urge to recognize two of the great progenitors of modern literature, William Shakespeare and Miguel de Cervantes Saavedra, who both died on 23 April 1616, at least according to the official history. Their work and the various arts that go into making books, as such, are celebrated around the world as staples of modern global civilization and the human element of culture. But the book is more than those sweeping historical energies; it is a concrete, observable register of intent and of meaning, which carries evidence of our humanity forward and informs and improves future worlds.