Fortune telling usually used the Book of Changes and the Eight Trigrams, which were ancient classics. The Book of Changes was a classic about life philosophy, divination, and philosophical thoughts. It included 64 hexagrams, line statements, and image statements. The Eight Trigrams were the most basic symbols in the Book of Changes. They represented the two poles of Yin and Yang, the six lines, and the three elements. They could be used to predict the future and explain the changes in things. The reason why fortune-telling was considered accurate was that fortune-tellers or fortune-tellers could predict and interpret the fate of their customers by combining their own experience and intuition with the contents of the Book of Changes and the Eight Trigrams. These predictions and interpretation were often based on the customer's historical background, personality, behavior, and birth characters, so they had a certain degree of accuracy. However, fortune-telling cannot guarantee the accuracy of predictions because fate is affected by many factors, including personal efforts, the surrounding environment, historical events, and so on. Therefore, fortune-telling was only a form of reference and entertainment, and should not be regarded as the absolute truth that determined one's life and destiny.