ABSTRACT
Three main ideas underlay the natural theory of dreams and constitute the focus of this chapter. First, based on the Hippocratic-Galenic system, "natural" dreams were understood as the natural by-products of the complex workings of the humoral system of the body in sleep. Second, the idea that certain dreams were caused by autonomous psychological processes was also common and derived from the ideas of Plato and Aristotle. Finally, writers argued that "natural" dreams were alternately caused by a range of external environmental stimuli, such as noises, the planets, the air and the direct environment of the sleeper. It was perhaps the close association between sleep and death for early modern people that imbued the seasons of nocturnal repose with an acute sense of vulnerability and heightened anxiety. For since sleep, like death, was a state in which the body lay immobile, unprotected and exposed to all physical and supernatural dangers, the need for spiritual and bodily protection was paramount.
