In 1973, at the
Mawangdui in
Changsha, a number of silk manuscripts were unearthed. Once they were collated these were dubbed "". The documents consist of a total of twenty-seven chapters divided into three parts. The first, consisting of fourteen chapters, contains Su Qin's correspondence and conversations and provides information from which the historical truth regarding the
Strategems of the Warring States may be discerned and errors in Su Qin's biography in the
Records of the Grand Historian identified. According to this written evidence, Su Qin's era followed that of
Zhang Yi, during the reign of King Zhao of Yan. In conjunction with
Gongsun Yan, Su Qin continued Zhang Yi's mutual confrontation with the Horizontal Alliance of
Xi Shou. Su Qin had four older brothers: Su Dai, Su Li, Su Bi and Su Hu. Under his teacher Yu Qi, Su Qin studied all aspects of the operations of the Vertical Alliance and the Horizontal Alliance. He also pored over the books in Yu Qi's collection and found one titled "Minister Yin Fu’s Plan", which Su Qin studied hard for many years, and accepted that its methods would be enough to gain the support of the reigning monarch. After
King Zhao of Yan (312–279 BC) ascended to the throne, the state suffered upheaval and bloodshed so the king, planning to strengthen his state and avenge former humiliation, summoned his sages. Su Qin immediately left Zhou and travelled to the Yan. For King Zhao of Yan, Su Qin carried out his first meritorious service by petitioning
King Xuan of Qi to return the ten cities he had previously snatched. The Yan sent a prince as hostage to the Qi with Su Qin acting as envoy. This was in the seventh year of the reign of
King Min of Qi, 294 BCE when the government of the Qi was presided over by
Lord Mengchang. Su Qin was treated well in Qi and was on friendly terms with Lord Mengchang before his return to Yan. In 292 BCE, the tripartite forces of Qi, Zhao and Qin were using all their efforts to fight over territory belonging to the
State of Song. Su Qin suggested a plan to King Zhao of Yan whilst guaranteeing that he could be "trusted as much as Wei Sheng" and that details of his secret meetings would go with him to the grave. Thereafter, Su Qin managed to drive a wedge between Qi and Zhao. Qi wiped out Song, which severely weakened Qi such that the Vertical Alliance of the other five states attacked. When
Yue Yi defeated Qi, King Min of Qi adjudged Su Qin guilty of dissention and had him torn limb from limb in public. Afterwards
Zou Yang said "Su Qin trusted nothing under heaven but he kept his promises to the State of Yan.
Sima Qian also commented, "Su Qin undertook a strategy of sowing dissention which led to his execution and all under heaven now mock him". In 1972, circumstantial evidence unearthed from the number one grave at Yinque Mountain, Linyi Prefecture, Shandong Province provided
Han Dynasty bamboo slips inscribed with
The Art of War by
Sun Tzu. The historian Li Ling mentions this in his simplified version
Sun Tzu in the "
Espionage" chapter, viz. "When the
Zhou flourished, Lu Ya was in Yin" followed by the sentence, "When Yan flourished, Su Qin was in Qi". Li Ling believes that this
Sun Tzu is not the same as the one handed down to later generations and is clearly the history of the late Warring States period. ==Cultural reference==