This research project examines the shifting relationship between curiosity and religion and argues for curiosity's centrality in new 'naturalized' accounts of religion in the early modern period (1500- 1800). At once seen as a natural human propensity, central to scientific knowledge, and a sin by some theological thinkers, British philosopher Thomas Hobbes puts curiosity to new and transformative use, making it the foundation of his explanation of religion and, in doing so, providing the resources for a naturalized account of religion, or an account that appeals to psychological, cognitive, and social features of the human being. Religion begins to be seen as a human social practice like any other, not an exceptional, supernatural phenomenon. The project uses Hobbes as an anchoring figure and then turns to David Hume and others in the period, including Spinoza and Malebranche, and focuses primarily on curiosity and related concepts like anxiety and wonder. The project analyzes the shifting relationship between new understandings of curiosity and religion in the period and seeks to use these insights to take on questions encountered today, for example, questions about whether and how religion might be part of our humanness, how and why religion persists as it does, and, in light of changing perspectives on curiosity, how to make better sense of the relationship between religious and scientific knowledge.