Abstract

This paper considers a seventeenth century argument for (substance) dualism propounded by Cambridge Platonist Ralph Cudworth that appeals to the nature of secondary qualities or sensations. I argue that, despite the widespread acceptance of the primary/secondary quality distinction, this argument is relatively unique for its time since seventeenth century arguments for dualism generally appeal, not to sensory qualities, but to thought, language, rationality, and volition. Indeed, for many, sensations are the most embodied of mental phenomena. I draw points of comparison and contrast between this argument, and nineteenth and twentieth century qualia-based arguments for (property) dualism. Finally, although such an argument might reasonably be called a “Lockean argument for substance dualism,” given Locke’s influential popularization of the primary-secondary quality distinction, I argue that it is not, in fact, an argument to which Locke would subscribe.