CHAP. XXI.
Of Dreams.
a 1.1 DReaming is an affection of the sensory part, in as much as it is phantastick. A Dream is an apparition or phantasme seen in sleep.
After the functions of the externall senses, there remain their motions and similitudes induced by their objects into their Or∣gans. These occurring in sleep cause dreams, but not at all times, nor at every age, for their species show not themselves but upon cessation of the humours. Hence Dreams are not immediatly after sleep, nor in infants soon after their birth, for then there is too great commotion by reason of the alimentary heat. As there∣fore in troubled water no image appeareth, or if any, much dis∣torted, but when it is calm, the image is rendred clearly; so when there is a tumult and agitation of the humours, there are no images presented, or those dreadfull, such as are the Dreams of melancholly and sick persons; but when the blood passeth smoothly, and the humours are setled, we have pure and plea∣sing Dreams; A Dream therefore is a phantasm caused by mo∣tion of sensibles already perceived by sense, occurring to Animals in sleep.