Sima Yi 司馬懿

Cui Yan told his friend Sima Lang that his younger brother, just come of age, was intelligent, clear-sighted, firm and decisive, and that Sima Lang himself would likely not match him; Sima Lang did not think so. Yang Jun met Sima Yi when he was sixteen or seventeen and said, "This is no ordinary man." Records, Wei 12 §16Records, Wei 23 §27

In the 24th year of Jian'an (219), when Guan Yu besieged Fancheng and Cao Cao discussed moving the capital away from Xu, Sima Yi and Jiang Ji argued that Sun Quan would not want Guan Yu to succeed; if Sun Quan were promised the lands south of the Yangtze as a fief and urged to strike at Guan Yu's rear, the siege would lift of itself. Cao Cao followed this advice. Under Emperor Wen, as Deputy Director of the Imperial Secretariat, he joined Wang Xiang and Xun Wei in the 3rd year of Huangchu (222) in kowtowing until their foreheads bled to plead for Yang Jun, who had been arrested after angering the emperor, but they were refused. In the 5th month of the 7th year of Huangchu (226), when Emperor Wen fell gravely ill, Sima Yi, as General-in-Chief Who Pacifies the Army, received the deathbed edict together with Cao Zhen, Chen Qun and Cao Xiu to assist the heir. Records, Shu 6 §10–11Records, Wei 23 §32Records, Wei 2 §52

When Emperor Ming took the throne, Sima Yi opened his own administrative office along with Cao Xiu, Cao Zhen and Chen Qun. In the 8th month of that year, when the Wu general Zhuge Jin and others raided Xiangyang, he defeated them and beheaded Zhang Ba, and together with Zhang He he pursued Sun Quan's detached commander Liu A and others as far as Qikou and defeated them. In the 12th month he became General-in-Chief of Agile Cavalry. In the 12th month of the 1st year of Taihe (early 228), when Meng Da, Administrator of Xincheng, rebelled, he received an edict to suppress him, and in the 1st month of the 2nd year of Taihe (228) he took Xincheng, beheaded Meng Da and sent his head on. Records, Wei 22 §20Records, Wei 3 §3–4 · 6–7Records, Wei 17 §50

Around that time he trained a navy in Jing Province, intending to go down the Mian River into the Yangtze to attack Wu; Zhang He came with the armies of Guanzhong to join him, but it was winter and the water was too shallow for large ships. In the 2nd month of the 4th year of Taihe (230) he became General-in-Chief and set out against Shu with the Grand Marshal Cao Zhen, planning to go up the Han River and meet Cao Zhen at Nanzheng. But heavy rains fell for more than thirty days and some of the plank roads were cut, and in the 9th month an edict recalled the army. Records, Wei 17 §52Records, Wei 3 §18–19Records, Wei 9 §67

In the 3rd month of the 5th year of Taihe (231), after Cao Zhen died and Zhuge Liang raided Tianshui, he received an edict to resist him. At Mount Qi, Sima Yi attacked Zhuge Liang while Zhang He attacked Wang Ping at the southern siege lines, but Wang Ping held firm and Zhang He could not prevail. In the 6th month, when Zhuge Liang withdrew for lack of provisions, Zhang He pursued him and was killed by an arrow. As General-in-Chief, Sima Yi held Huang Quan, who had surrendered from Shu, in high regard, asking him, "How many men like you are there in Shu?", and in a letter to Zhuge Liang he wrote that Huang Quan was always praising Zhuge Liang. Records, Wei 3 §21Records, Shu 13 §37 · 9Records, Shu 3 §12

In the 9th month of the 1st year of Qinglong (233), when the Xiongnu chieftain Hubo Juzizhi and others in Anding rebelled, he sent Hu Zun and others, who defeated them and forced their surrender. In the 2nd year of Qinglong (234), when Zhuge Liang came out through the Xie Valley, occupied the Wuzhang Plains and confronted him south of the Wei River, Emperor Ming issued an edict ordering him to hold his walls firmly and to pursue the enemy when it fled. Sima Yi approved Guo Huai's judgment that Zhuge Liang would contest the Northern Plain and stationed Guo Huai there. When Sima Yi repeatedly asked to give battle, Emperor Ming refused and sent Xin Pi as Military Adviser to the General-in-Chief. Zhuge Liang challenged him to battle several times, but Sima Yi strengthened his ramparts and did not respond; after a standoff of more than a hundred days, Zhuge Liang died of illness in camp in the 8th month. After the Shu army withdrew, Sima Yi inspected the site of its camp and said, "A genius of the realm!" Records, Wei 3 §32 · 36 · 40Records, Shu 5 §38Records, Wei 26 §69Records, Wei 25 §22

In the 1st month of the 3rd year of Qinglong (235) he became Grand Commandant. In the 1st month of the 2nd year of Jingchu (238) he received an edict to attack Gongsun Yuan of Liaodong. When officials objected that 40,000 troops were too many and the cost would be hard to bear, Emperor Ming said that a campaign of 4,000 li was no time to count costs and sent 40,000 men. Arriving in Liaodong in the 6th month, he sent Hu Zun to defeat Bei Yan and others, who had ringed Liaosui with more than twenty li of trenches, then headed southeast before swiftly turning northeast and making straight for Xiangping. While he besieged Xiangping, rains fell for more than thirty days, and some urged that he be recalled. Emperor Ming said, "Sima Yi meets danger by mastering change; the capture of Gongsun Yuan can be awaited by counting the days." In the 8th month Gongsun Yuan broke through the siege and fled, and was beheaded together with his son Gongsun Xiu at the spot where a meteor had fallen; Liaodong, Daifang, Lelang and Xuantu were all pacified. Records, Wei 3 §42 · 57 · 61–62Records, Wei 8 §47–49

In the 12th month of the 2nd year of Jingchu, when Emperor Ming fell ill, Liu Fang and others urged that the Grand Commandant Sima Yi be summoned at once to hold the imperial house together. The emperor had the summoning edict halted and then had it written again. In the 1st month of the 3rd year of Jingchu (239), Sima Yi, who had returned to Henei, was summoned by post horse and led into the emperor's bedchamber; Emperor Ming took his hand, charged him to assist his young son together with Cao Shuang, and died that day. When Cao Fang, Prince of Qi, took the throne, Sima Yi assisted in the government together with Cao Shuang, and in the 2nd month he became Grand Tutor, while continuing as before to command troops and oversee the armies. According to the Biography of Cao Shuang, the move to Grand Tutor was Ding Mi's scheme, meant to honor him outwardly while having the business of the Imperial Secretariat pass through Cao Shuang first. Records, Wei 3 §63 · 65Records, Wei 14 §151–153Records, Wei 4 §2 · 5Records, Wei 9 §72

In the 5th month of the 2nd year of Zhengshi (241), when Zhu Ran of Wu and others besieged Fancheng, he led forces to resist them, and the Wu army withdrew in the 6th month. He approved Deng Ai's proposal for military-agricultural colonies along the Huai River and had it carried out in full. According to the Biography of the Lord of Wu, in the 6th year of Chiwu (243) Sima Yi led an army into Shu County and Zhuge Ke moved to Chaisang; Sun Quan later remarked that Sima Yi had withdrawn within ten days. In the 5th year of Zhengshi (244), when Cao Shuang sought to attack Shu, Sima Yi tried to dissuade him but could not stop him. Records, Wei 4 §12Records, Wu 2 §96 · 99 · 101Records, Wei 28 §52–53Records, Wei 9 §74

At first Cao Shuang served Sima Yi like a father, but after he promoted He Yan and others, affairs no longer went through Sima Yi, who pleaded illness to avoid Cao Shuang while secretly making preparations. In the winter of the 9th year of Zhengshi (248), when Li Sheng, about to leave as Inspector of Jing Province, came to call, Sima Yi pretended to be gravely ill and showed himself frail, and Li Sheng believed it. In the 1st month of the 1st year of Jiaping (249), when the emperor went to pay respects at the Gaoping Tomb with Cao Shuang and all his brothers in attendance, Sima Yi first seized the arsenal and then stationed himself at the floating bridge over the Luo River. In his memorial he stated that when he returned from Liaodong, the late emperor had grasped his arm and entrusted him with affairs after his death, and that by order of the Empress Dowager he was relieving Cao Shuang and his brothers of their military command. Urged by Xu Yun and Chen Tai, Cao Shuang admitted his guilt and was dismissed. Later, on the testimony of Zhang Dang, Cao Shuang, He Yan and others were found to have plotted rebellion, and their clans were exterminated to the third degree. Sima Yi was appointed Chancellor but firmly declined. Records, Wei 9 §76 · 79–85 · 87–88Records, Wei 4 §28–29

In the 3rd year of Jiaping (251), on receiving a report that the Grand Commandant Wang Ling was plotting to depose the emperor and enthrone Cao Biao, Prince of Chu, Sima Yi led the central army by water, first issuing a pardon, and pressed him by bringing the main force to Baichi. When Wang Ling came out having bound himself, Sima Yi untied him, returned his seal and ribbon and his tally and axe, and had him escorted to the capital, but Wang Ling took poison and died at Xiang County. Sima Yi went on to Shouchun and pursued the affair to the end; Cao Biao was ordered to die, and those implicated had their clans exterminated to the third degree. When Sima Yi died on the wuyin day that autumn, his son Sima Shi became General-in-Chief Who Pacifies the Army and Controller of the Imperial Secretariat. Records, Wei 4 §32–33Records, Wei 28 §8–10

The assessments of him preserved in Chen Shou's text are all the words of others. An edict of the 3rd year of Jingchu said that he embodied the Way, was upright and straight, had served three generations with loyalty, captured Meng Da in the south, crushed Shu in the west and destroyed Gongsun Yuan in the east. In the 11th month of the year he died, when the meritorious officials to be honored in the temple of Taizu were re-ranked by office, he was placed at the very top for his high merit and noble rank. Zhuge Ke of Wu remarked that Sima Yi had killed Wang Ling and then died himself, and that his son was young and weak, so now was the time to attack Wei. Records, Wei 4 §5 · 33Records, Wu 19 §35