ABSTRACT
Chapter 4 clarifies how Joseph Glanvill’s fellowship of the Royal Society of London influenced his approach to the existence of witchcraft. The general contextualization of his Letter of Witchcraft within contemporary witchcraft debates and the overview of Glanvill’s metaphysics enable a closer analysis of the Letter as the consistent, core component of Glanvill’s work on witchcraft, the Saducismus triumphatus. Building on the work of Moody Prior and George Lymen Kittredge, this chapter suggests that one of Glanvill’s primary intentions in the work was to seek testable hypotheses that might provide the foundation for an experimental investigation into witchcraft. It explores how Glanvill’s ideas related to those presented by sceptics, especially John Webster, Reginald Scot and Robert Burton. It also shows how Glanvill’s eclectic method enabled him to build upon current natural philosophical theories, relating in particular to new observational instruments like the air-pump, as well as theories of contagion and effluvia, and experiments with blood transfusions, to modernize his explanations and produce innovative hypotheses inspired by the work of Robert Boyle, George Starkey and Robert Hooke. This chapter introduces Glanvill’s hypothesis of poisonous vapours and shows how this theory is a product both of Glanvill’s metaphysics and his natural philosophy.
