This essay brings probabilistic reasoning into concerted dialogue with book-historical and sociological approaches to world literature. Using extensive bibliographic data about literary translations into Japanese during the modern era, it develops a series of case studies at interrelated scales-the literary anthology, world library collections, and individual readers-to reason about the likelihood of certain authors or works being plucked from the swirling currents of the global traffic in books. At each scale, I consider how such data might inform the interpretations we give to the choice of one author over another in a given context. Woven into these case studies is an extended reflection on the history of probabilistic reasoning from the late-eighteenth century to the late-twentieth. What, this essay ultimately asks, might literary historians gain from taking this history seriously in our own appeals to chance as a form of historical explanation?