From An excerpt from the beginning: Part I. - Incubation in Pagan Temples. - I. Introduction In the ancient science of divination, four working methods were commonly practised. Revelations of the future were deduced from natural portents, from the flight of birds, from entrails of sacrificial victims, or from dreams. It was the fourth way that had, for obvious reasons, the greatest vogue. Belief in the significance of dreams has always been widespread, and the supernatural authority attached to them by the ancients needs no demonstration. From Pharaoh's dream downwards there are recorded many illustrations of the importance with which they were regarded not only by the ignorant and superstitious, but by philosophical thinkers.

The philosophy of dreams, as they were regarded in the fourth century B.C., was held to be that in sleep the soul was freed from the body so that it could soar into spiritual regions, and commune with divine beings. Accordingly, memories of what had passed in sleep were to be cherished as divine revelations granted to the soul. The science of oneiromancy was the subject of much study. Artemidoros of Ephesus has five books of "Oneirocritica," where he attempts some explications and relates many instances of dreams. Dreams are divided by him into five classes, of which the fifth is the most important for divination. That is the class of "chrematismoi" or oracles.

The division given by Artemidoros is found again in Macrobius, "Somnium Scipionis" (i. 3), where the following definition of an oracle is given: - It is a case of an oracle when, during sleep, a relative, or other sacred or authoritative person, or a priest, or even a god, declares openly what is going to happen, or not to happen, or what must be done or avoided." Two other kinds of dreams worthy of interpretation are given - the vision, and the "somnium" or dream proper. In the vision, a person sees what is going to happen in exactly the way in which it will take place, and the somnium is a dream so complicated and obscured by figures that it cannot be understood with- out interpretation. Incubation was the method by which men sought to entice such dreams. Visions, in which a revelation regarding the future was given by a god or a divine messenger, would be precious and greatly to be desired by those who believed in their infallibility. Naturally people would seek for divine guidance in distress and difficulty, and out of their efforts to obtain it arose the practice of incubation. Suppliants approached the god by sacrifices and performance of rites best calculated to win his favour, and then in the place most likely to be visited by the deity, either the temple, or the appointed sleeping-hall, lay down to sleep awaiting a divine visitation.

The gods in whose temples incubation was practised were chthonian deities, heroes who had gone down into the earth and were invested with her powers. Two of the chief faculties of the earth were the power of sending dreams, and the gift of healing. As a giver of dreams she is apostrophised in the Hecuha of Euripides (1. 70): - "O Lady Earth, sender of black-winged dreams." The healing powers of the earth were expressed in the production of herbs that gave life or death, and were transmitted to the chthonian gods who had entered into her. The combination of these two faculties brought it to pass that the temples of these deities were the centres of medical divination, obtained through incubation. Illness was the most frequent motive for consultation; hence the primary aspect of incubation is medical. But the gods were not consulted solely on account of disease.

In any case of difficulty or distress incubation might be tried.