A book illustrated in color and three ancient Chinese coins. The I-Ching, or Book of Changes, is one of the oldest literary works in existence. The sage, Fu-hsi, studied the broken and solid lines that appeared on a tortoise shell and discovered that they comprised a perfect mathematical model. From there he created eight trigrams that symbolize eight elements found in nature: heaven, earth, water, fire, thunder, mountain, wind and lake. Each hexagram has a name and describes a more or less concrete situation. According to the Book of Changes, nothing is permanent, everything is in the process of change. That which is excessively Yin transforms into Yang and vice versa. By using the three coins method, you can determine each line of the hexagram. Through the lines that appear you can determine the point in the process in which you find yourself, what awaits you in the future, and advice about how to act in the present.