The scientific study of atheism and unbelief is at a pivotal turning point: past research is being evaluated, and new directions for research are being paved. Organizations are being formed with an exclusive focus on unbelief research, and large grants are funding the topic in ways that historically have never happened before. This article serves as an introduction to the state of the literature and study of evolutionary perspectives towards unbelief, which incorporates cognitive, adaptive, and biological contributors. This article serves (...) to contextualize the subsequent articles, which all have distinct perspectives on the evolutionary factors that contribute towards unbelief. (shrink)