Introduction

Abstract The introduction outlines competing views on how to interpret alchemy, presents the book’s definition of spiritual alchemy, and provides an outline of the work. Throughout the past three centuries, alchemy has often been viewed as either fraudulent superstition, introspective religion, or practical science. Bringing together the latter two in a way that challenges our habit of distinguishing sharply between science and religion, spiritual alchemy was based on early-modern concepts of spiritus, a subtle matter pervading the universe. As a concept, spiritus transitioned freely between laboratory alchemy, medicine, cosmology, and even theology. In the process, it could give rise to heterodox implications, something that also affected spiritual alchemy.