The deckle edge dates back to a time when you used to need a knife to read a book. Those rough edges simulate the look of pages that have been sliced open by the reader. The printing happened on large sheets of paper which were then folded into rectangles the size of the finished pages and bound. The reader then sliced open the folds.
Paper knives, variants of letter openers, were used for this purpose. Italo Calvino’s If on a Winter’s Night a Traveler, which speaks directly to the reader and describes the reader’s experience reading the novel, makes extensive reference to these literary knives:
“This volume’s pages are uncut: a first obstacle opposing your impatience. Armed with a good paper knife, you prepare to penetrate its secrets. With a determined slash you cut your way between the title page and the beginning of the first chapter.”
Opening a book can already feel like opening a gift. Armed with a knife and freeing the pages and the story hidden beneath the folds, it becomes something more, “a penetration of its secrets” and an act of discovery, shot through with a suggestion of violence and danger or of the painful gestation of the words themselves.