The Liushu lüe 六书略 "Abstract on the six types of Chinese characters" is included in Zheng Qiao's 郑樵 alternative history Tongzhi 通志 from theSong period 宋 (960-1279). The term six types of Chinese characters(liushu 六书) has been invented by the Later Han period 后汉 (25-220 CE) scholar Xu Shen 许慎. Although he shortly explains these styles in the postface of his dictionary Shuowen jiezi 说文解字, he does not consistently make use of this concept. Zheng Qiao tries to develop a more concrete concept and increases the six styles to twelve by considering various combinations of symbol and sound or symbol and meaning for the creation of characters. Zheng's attempts laid the ground for a lot of later studies on this issue, like Dai Tong's 戴侗 Liushugu 六书故, Zhou Boqi's 周伯琦Liushu zheng'e 六书正讹, Yang Huan's 杨桓 Liushutong 六书统, Wei Xiao's 魏校 Liushu jingyun 六书精蕴, Zhao Guze's 赵古则 Liushu benyi 六书本义 and Zhao Huanguang's 赵宦光 Liushu zhangjian 六书长笺. Zheng Qiao's own essay Liushuzheng 六书证 is lost.

Zheng Qiao tried to show that the character types xiangxing 象形 "illustration of a shape" and zhishi 指事 "pointing at things" actually followed the same idea of drawing something, a fact also valid for the typesxiesheng 谐声 "harmony and sound" and zhuanzhu 转注 "comment by turning" which are both relying on the sound of the word. Of all character types, Zheng Qiao says, drawn objects (xiangxing) are the most basic. What can not be drawn as an object, is an affair (shi 事). An affair that can not be pointed at (zhishi) with a written character, is an idea (yi 意). Ideas that can not be brought together (huiyi 会意 "assembled meanings") in one written character, have to be express by a sound (sheng 声). Sounds have all certain rules of harmony (xie 谐). Only if these means of writing are not sufficient, it is necessary to borrow (jiajie 假借 "wrongly borrowed") another character for a word. This is Zheng Qiao's explanation of the development six types of characters.