Yupian (Jade Chapters) provides the phonetic reading using the character for zi, while Jiyun (Collected Rhymes) and Leipian (Classified Chapters) provide the phonetic reading using the character for ze. It is pronounced zou. Shuowen Jiezi (Explanation of Simple and Compound Characters) states that it is the character for jie. Zhenge (Correction of Errors) states that it is the character for jie written in reverse. Both jie and the reversed form represent the shape of inflection and cadence. The character for yi (to suppress) is derived from this form. In ancient times, tally seals were divided into two halves; the person giving the seal held the left half, and the recipient held the right half. The ancient characters for jie and its reversed form were written in this manner. Later, in clerical script, they were written as the characters for jie and zou.