The term "pal-gwae" refers to the eight trigrams associated with the I Ching hexagrams. Bagua charms may also depict the Bagua (the Eight Trigrams of Taoist cosmology). For example, Baguazhang is based on the Taoist philosophy of the eight trigrams (Bagua). It featured a yin-yang symbol surrounded by four trigrams. The Eight Trigrams for divination is explained all nature phenomenon. Hexagrams are formed by combining the original eight trigrams in different combinations. In 1988, he published "The Trigrams of Han&colon; Inner Structures of the I Ching". The element of Metal corresponds with the trigrams of Heaven (Qian) and Lake (Dui). The Eight Trigrams uprising of 1813 broke out in China under the Qing dynasty. The Water (Kan) and Fire (Li) trigrams correspond directly with the Water and Fire elements. The adjustment of the trigrams is symmetrical by forming exact contrary pairs. The element of Earth corresponds with both the trigrams of Earth (Kun) and Mountain (Gen). Due to their tripartite structure, they are often referred to as Eight Trigrams in English. Together, the trigrams represent movement and harmony as fundamental principles. All of these phases are represented within the trigrams.