The Thirteen Classics (traditional Chinese: 十三經; simplified Chinese: 十三经; pinyin: Shísān Jīng) is a term for the group of thirteen classics of Confucian tradition that became the basis for the Imperial Examinations during the Song dynasty and have shaped much of East Asian culture and thought.
The classics are: The tradition of a defined group of "classics" in Chinese culture dates at least to the Warring States period, when the Zhuangzi has Confucius telling Laozi "I have studied the six classics—the Odes, the Documents, the Rites, the Music, the Changes, and the Spring and Autumn Annals".
By the Tang dynasty references to "nine classics" were common, though the nine works themselves vary depending on the source.
By the time of the Southern Song dynasty, the number and specific books in the "thirteen classics" were universally established.
The Thirteen Classics formed the texts used in the Imperial examinations, and their 600,000+ characters, in effect words, were generally required to be memorized in order to pass.