This chapter emphasises the seventeenth-century contribution about the problems of mind and soul, in particular, the way in which the new mechanical philosophy suggested both new problems and new solutions to old problems connected with life and thought. It discusses various views concerning the soul and the existence, and nature of the incorporeal substance that most seventeenth-century thinkers posited. The chapter provides a brief discussion of some of the reactions to the mainstream accounts of mind and soul. Rene Descartes's conception of the soul was a significant departure from the Aristotelian tradition in which he was educated. Descartes's soul has no connexion whatsoever with the vital functions that are so central to the Aristotelian conception of the soul. In order to bring out the distinctive features of the Cartesian position, the chapter examines the views of two of Descartes's contemporaries who also argued for the existence of an incorporeal human soul: Kenelm Digby and Pierre Gassendi.