Sima Yi and Yang Xiu were both Cao Cao's right-hand men, both of whom were only eight high, and could both take over Cao Cao's descendants and monopolize power. So why did Cao Cao only kill Yang Xiu, but not Sima Yi, who launched the "Gaopingling Rebellion" 29 years later?
According to the content of the interpretation and related historical materials, the analysis is as follows.
First, Cao Cao was not a faint person, so how could he kill people casually?
Cao Cao kills people, and there are generally reasons for killing people. For example, in the yanyi, he killed Yang Xiu because Yang Xiu guessed Cao Cao's intentions in the Battle of Hanzhong according to cao Cao's military orders. He thought that cao cao's password was "chicken ribs", so he made himself wise to think that Cao Cao regarded Hanzhong as a chicken rib, tasteless, and abandoned it, and would soon withdraw his troops. He also spread rumors in the Cao camp, shaking the hearts of the army, and even the general Xiahou Huan was seduced by Yang Xiu, packing up his things and preparing to return to the north in the near future. He was clever, randomly guessing the mind of the lord, which was a big taboo, and he also paid the price of his life for it.
At the same time, Sima Yi was a man of Taoguang and obscurity, and as early as when Cao Cao was recruited as an official, he pretended to be ill because he was unwilling to assist Cao Cao. The first time he deceived Cao Cao, the second time he really couldn't prevaricate, so he reluctantly became Cao Cao's master. After Sima Yi served Cao Cao, he worked diligently, worked hard and complained, and commuted to and from work on time every day. He knows that more words will be lost, and low-key is the king' way and the way to survive.
Second, Yang Xiu was involved in the dispute between Cao Pi and Cao Zhi's sons, and Sima Yi stayed out of the matter.
Yang Xiu, like Sima Yi, was from a famous family, and he was the son of Yang Biao, the former eunuch of the Yang clan of Hongnong. The last thing he should have done was to intervene in the shizi battle between Cao Pi and Cao Zhi. In Cao Cao's test of Cao Zhi and Cao Pi, Yang Xiu, believing that he was the lord of the Xiang Mansion, could also spy on Cao Cao's intentions and help Cao Zhi pass smoothly many times, and Cao Zhi still passed with a high score.
In fact, this greatly violated Cao Cao's taboo, and Yang Xiu's killing was beyond reproach. Who the Prince of Wei should choose and who not to choose is Cao Cao's family affair, and it is not good for others to intervene. Yang Xiu intervened, so he was jealous of Cao Cao and was finally killed. Even if Cao Cao did not kill Yang Xiu, Cao Pi, who was the winner of the competition, would also kill.
On the other hand, Sima Yi knew very well that the waters of the Shizi Controversy were very muddy and not something he could touch. Therefore, in the face of the intensifying dispute between the sons of the world, Sima Yi has always stayed out of the matter, does not care about himself, and hangs high. He was not noticed by Cao Cao and liquidated by Cao Cao.
Third, Cao Cao did not know that Sima Yi, the obedient little sheep, would become the gravedigger of his dynasty in the future.
Cao Cao himself started by "holding the Son of Heaven hostage to order the princes", and he put liu Xie, the emperor of Han Xian, into the air, making him a puppet with no real power, and leaving him at his mercy. Unexpectedly, Cao Cao's great-grandson Cao Fang also followed in the footsteps of Emperor Xian of Han. What is even more tragic is that Cao Xian's situation is not as good as that of Emperor Xian of Han, and he was actually killed by Sima Zhao's general Chengji in the street.
However, when Cao Cao was alive, how could he have imagined that his right-hand man Sima Yi would learn from himself in the future, take over the emperor, monopolize power, and finally replace him with his descendants. Cao Cao was not a god, he didn't know.
And Yang Xiu has shown a posture of enthusiasm for power struggle, which has to make Cao Cao think. Cao Cao himself held great power through the emperor. He was afraid that Yang Xiu would assist Cao Zhi and seize great power and elevate Cao Zhi. Therefore, Cao Cao killed Yang Xiu and did not kill Sima Yi indiscriminately.
Summary: Cao Cao killed Yang Xiu, the most important thing is that Yang Xiu broke the rules, guessed his own meaning without authorization, and also helped Cao Zhi cheat. Sima Yi, on the other hand, had been following the rules and regulations until Cao Cao's death, and he did not show a "disobedient heart".
Cao Cao was not a god, and without the superpowers of the prophets, it could not be predicted that Sima Yi, who had always been obedient, would launch the Gaopingling Rebellion 29 years later, eliminate the political enemy Cao Shuang, and elevate the Cao Wei Emperor to become the second Cao Cao. Therefore, Cao Cao had no reason to get rid of Sima Yi, and he had no reason to kill his loyalists at will.