I Ching (易经) means Book of Changes. It is an oracular Chinese book which goes back to the year 1200 b.C. It is believed to describe the consultant's current situation and it predicts how his or her future will be if the right position is adopted. There are several methods of consulting, being the one with coins the most popular. Chinese coins are traditionally used because of its symbolic ancestral connection. These coins are round, with a square hole in the middle. The roundness represents the creative principle of Yang and the square represents the principle of Yin (the limited space of the receptive Earth).