The enigmatic relationship between religion and science continues to challenge European societies and concepts of modernity. This book argues that European secularism, rather than dismissing religious truth claims, has been religiously productive in its own right. The institutional establishment of new disciplines in the nineteenth century, such as religious studies, anthropology, psychology, classical studies, and the study of various religious traditions, led to a professionalization of knowledge about religion, which in turn attributed new meanings to it. This attribution of meaning resulted in the emergence of new religious identities and practices. In a dynamic closely linked to this discursive change, the natural sciences adopted religious and metaphysical claims, integrating them into their framework of meaning, resulting in a unique form of synthesis.