Each taegeuk form is represented by a trigram (such as ☱); trigrams are divination symbols derived from the I Ching. The trigram for Taegeuk Yi Jang represents the concept of "Tae." (Note: the word tae here is not the same as the tae in taekwondo.) Tae is said to symbolize "inner firmness and outer gentleness," the archetype being a river or lake: gentle and flowing at the boundaries, but firm and resolute underneath. The idea is that movements in this form should be fluid, and yet be performed firmly, with good control. (See the article Taegeuk for additional detail regarding the symbolism of this form.)