Descartes' philosophy represented one of the most explicit statements of mind-body dualism in the history of philosophy. Its most familiar expression is found in the Meditations (1641) and in Part I of The Principles 0/ Philosophy (1644). However neither of these books provided a detailed discussion of dualism. The Meditations was primarily concerned with finding a foundation for reliable human knowledge, while the Principles attempted to provide an alternative metaphysical framework, in contrast with scholastic philosophy, within which natural philosophy or a scien tific explanation of...