Imagination has always been recognised as an important faculty of the human soul. As mediator between the senses and reason, it is rooted in philosophical and psychologicalmedical theories of human sensation and cognition. Linked to these theories was the use of the imagination in rhetoric and the arts: images had not only an epistemological role in transmitting information from the outside world to the mind's inner eye, but could also be used to manipulate the emotions of the audience. In this tradition, with Cicero and Quintilian as its auctoritates, images were used to arouse and manipulate the emotions. Both traditions had to be revalued in the seventeenth century with the advent of a mechanist, Cartesian picture of human cognition and the physical world. In spite of their usual suspicion of imagination, which was commonly associated with illusions, dreams and fiction, seventeenth-century philosophers realised that the imagination also had its place in mathematical, scientific and philosophical thinking. This volume covers both the philosophical-psychological as well as the humanist-rhetorical traditions, discussing key figures but also treating hitherto neglected texts and writers.