One of the simplest divination methods in the world is also one of the oldest. Called ‘Urim and Thumin’ in the Bible, and practiced by the ancient priesthood of Israel, it consisted of two stones, one light stone and one dark stone, which were stored in the high priest’s breastplate. One stone was assigned the meaning ‘Yes’ and the other stone was assigned the meaning ‘No.’ It was consulted for answers to questions of a fairly direct nature—should I go left or right? Should we begin planting this week? Should this man make a sacrifice of a sheep and two turtledoves to Jahweh on this matter? Should I take Rachel, daughter of Joseph, as my concubine? This system of divination was the one featured in Paolo Coelho’s novel, The Alchemist.
Urim and Thumin, which could also be called ‘The Yes and No Stones,’ is a binary divination system. Other binary divination systems are the I Ching of China, which relies on a series of 64 different hexgrams or sets of six lines, which have either broken or unbroken lines in their formation. One African divination system employs a series of eight discs carved from tortoise shell and strung together, with each shell inscribed with some combination of 1s and 0s. The string of eight shells is ritually thrown by a diviner, who then draws from it any one of a number of answers. Urim and Thumin is the simplest divination tool in the world. The African divination tool just described is one of the most complex. Both are binary-based, which gives you an idea of how flexible a binary-based divination system can be.