Yanji 衍極

Yanji 衍極 is a book on calligraphy written during the Yuan period 元 (1279-1368) by Zheng Shao 鄭杓 (fl. 1321), courtesy name Zijing 子經, from Luoyuan 羅源 or Putian 莆田 (both in today's Fujian province) and commented on by Liu Youding 劉有定, courtesy name Nengjing 能靜, style Yuanfan 原范, from Putian.

Zheng Shao was educational instructor (jiaoyu 教諭) of Nan'an 南安 and was acquainted with Chen Lü 陳旅 (1288-1343). Apart from the Yanji, he wrote an excerpt, Yanji jizai 衍極記載 in three chapters, and the calligraphic texts Shufa liuchuan tu 書法流傳圖 and Xueshu cidi tu 學書次第圖 which all are related to the Yanji. Only the core text has survived and is recorded in the Ming-period 明 (1368-1644) encyclopaedia Yongle dadian 永樂大典.

The title of the book is derived from the first two words of the text. The original preface of Li Qi 李齊 (courtesy name Zhongsi 仲思) is dated 1321. The oldest print was produced in 1485. Further editions were published in 1501 and 1619 (Shen Shuaizu 沈率祖).

The Yanji is divided into 5 chapters. The chapter "Utmost simplicity" (Zhipu 至樸) gives a brief account of the origins and developments of the Chinese script and of calligraphy and the achievements of various calligraphers from the Zhou 周 (11th cent.-221 BCE) to the Tang 唐 (618-907) and Song 宋 (960-1279) periods. The chapter "Essentials of calligraphy" (Shuyao 書要) describes the various styles of calligraphy and helps to discern authentic pieces of art from forgeries. It also promotes the use of the six styles of calligraphy (liushu 六書), with a clear focus on the seal script and the chancery script. Chapter three, "Creation of calligraphy" (Zaoshu 造書) discusses the correctness and incorrectness of calligraphy and prevalent mistakes, as well as the study of Chinese characters and the assessment of the quality of ancient stele inscriptions. "Ancient teachings" (Guxue 古學) helps to evaluate the strengths and weaknesses of calligraphies from the Han to the Tang period as well as the rating of inscriptions on metal objects and stone steles. The last chapter, "Heaven has five" (Tian wu 天五) gives instructions on the use of the brush and on the identification of stele inscriptions and model calligraphies (tie 帖).

Qi Boheng 齊伯亨 once named his study (Yangjitang 衍極堂) according to the book because he was much impressed by Zheng Shao's teachings. The text is extensive and written in careful words, but it is not as concise and difficult as it could be, and has no clear order, but is instead too precise in many places. However, the interpretations by Liu Yuding help to give the theoretical parts of the text more practicality.

The text is found in a version of 2 juan in the series Shiwanjuanlou congshu 十萬卷樓叢書, Meishu congshu 美術叢書 and Siku quanshu 四庫全書, and in a 5-juan version in the series Baoyantang miji 寶顏堂秘笈, Shuofu 說郛 (Wanwei Shantang 宛委山堂 edition) and Xu baichuan xuehai 續百川學海.