Do away with the old and set up the new. Ge (革) and ding (鼎) are two trigrams in The Book of Changes. In Commentary on The Book of Changes, it is explained that the lower ge trigram symbolizes fire and the upper ge trigram symbolizes water. Since fire and water are opposed and in conflict, and they cannot keep an original state of equilibrium, changes are bound to occur. Consequently, the ge trigram implies change of an unsuitable old state of affairs. The lower ding trigram symbolizes wood and the upper ding trigram symbolizes fire. When people throw the wood into the fire, they can cook their food in a ding. Thus, the ding trigram signifies the creation of new things. Following the doctrine in Commentary on The Book of Changes, later people combined the two together to represent an outlook advocating changes.

Ge trigram signifies doing away with the old; ding trigram symbolizes setting up the new. (The Book of Changes)