博而不精 — “To have broad but not deep knowledge”

During the Eastern Han Dynasty, Zheng Xing was a renowned classical scholar, famous for his research on the "Zuo Zhuan" (Zuo's Commentary on the Spring and Autumn Annals). His son, Zheng Zhong, began studying this classic with his father at the age of twelve. Later, Zheng Zhong also delved into other classical works such as "Zhou Yi" (Book of Changes), "Mao Shi" (Mao's Commentary on the Book of Odes), and "Zhou Li" (Rites of Zhou), making him widely learned and knowledgeable about almost everything, gaining considerable fame in high society.

After Zheng Zhong became an official, he spent his leisure time explaining classics like "Mao Shi" and "Zhou Li" to young scholars, and devoted significant effort to annotating the "Zuo Zhuan". He eventually completed this annotation, which, upon circulation, became as renowned as another scholar Jia Kui's annotation of the "Zuo Zhuan," both receiving high praise from academics.

At that time, the most famous classical scholar was Ma Rong. He had annotated numerous classics including "Zhou Yi," "Shang Shu" (Book of Documents), "Mao Shi," "San Li" (Three Rites), "Lun Yu" (Analects of Confucius), and "Xiao Jing" (Classic of Filial Piety), bringing the study of ancient texts to a mature stage. Consequently, he had thousands of disciples. Besides annotating classics, Ma Rong also annotated "Laozi" and "Huainanzi." His teaching style was distinctive: he sat on a high platform, surrounded by a silk curtain, with students sitting in front listening to his lectures, while behind him, a band of female musicians played music.

After studying the "Zuo Zhuan," Ma Rong also planned to annotate it. He carefully read Jia Kui's and Zheng Zhong's annotated versions and concluded: "Jia Kui's annotation is profound but not broad, while Zheng Zhong's annotation is broad but not profound. If it were both profound and broad, how could I surpass them?" Ma Rong felt that these two annotations each had their strengths and together compensated for their respective shortcomings. Thus, he decided not to annotate the "Zuo Zhuan" himself. The idiom "博而不精" (broad but not profound) originates from Ma Rong's assessment of Zheng Zhong's work.