divination, practice of foreseeing future events or obtaining secret knowledge through communication with divine sources and through omens, oracles, signs, and portents. It is based on the belief in revelations offered to humans by the gods and in extrarational forms of knowledge; it attempts to make known those things that neither reason nor science can discover. It is known that divination by means of crack patterns in shells was practiced in China as early as the 2d cent. B.C. In the West, before divination spread throughout the Greco-Roman world, various branches of the practice as used by the Chaldaeans were considered superior to all the sciences. Among those branches the most significant were the study of the flight of birds, the study of water and water patterns, the study of the entrails of sacrificial animals (haruspication), and the inspection of animals' shoulder blades (scapulimancy). The Greeks placed their greatest trust in the wisdom of the oracle. Divination was essential to all the religions of classical antiquity; no state and hardly any individual would have dared undertake a significant action without first consulting the gods. Divination persists to the present day in crystal gazing, palmistry, fortune-telling, and astrology.
See W. R. Halliday, Greek Divination (1913, repr. 1967); W. B. and L. R. Gibson, The Complete Illustrated Book of Divination and Prophecy (1973).