Xin Pi (before 175[2] - c. 235),[a] courtesy name Zuozhi, was an official of the state of Cao Wei during the Three Kingdoms period of China.
Along with his elder brother Xin Ping, he started his career in the late Eastern Han dynasty as an adviser to the warlord Yuan Shao.
Xin Pi was from Yangzhai County (陽翟縣), Yingchuan Commandery (潁川郡), which is around present-day Yuzhou, Henan.
"[11] Xin Pi replied: "Wise Lord, you shouldn't be asking about trust and deceit; you should be talking about the current situation as it is.
When the Yuan brothers fight each other, the more important question is not whether you can take advantage of the situation to drive a deeper wedge between them, but rather you should be talking about seizing the opportunity to unify and pacify northern China.
Given your might, it will be very easy for you to defeat an exhausted enemy, just as a gust of autumn wind can easily scatter leaves to the ground.
Heaven has granted you, Wise Lord, an opportunity to eliminate Yuan Shang, yet you choose to attack Jing Province instead.
If they have a good harvest next year, recognise the peril they are in, and take appropriate actions to correct their mistakes and cover their weaknesses, then you would have lost an opportunity to subdue them by military force.
During the Battle of Ye, when Yuan Shang's adviser Shen Pei saw that Cao Cao's forces had broken through Ye's defences, he blamed Xin Pi for the downfall of the Yuan family so he ordered his men to execute Xin Pi's family members.
He started hitting Shen Pei on the head with his horse whip while scolding him: "Slave, today you shall meet your doom!"
[26] At the time, there was a discussion in Cao Pi's imperial court on the issue of whether to change the starting date of the calendar year.
Xin Pi argued that it was unnecessary to do so since there was a peaceful transition from the Eastern Han dynasty to the Cao Wei state, just like how Yu succeeded Shun in ancient times.
He also quoted sayings from Confucius and the Zuo zhuan which mentioned that the starting date of the calendar year set in the Xia dynasty was the most legitimate one, and therefore it would be best for the Cao Wei state to follow it.
While the others became afraid upon seeing the emperor's facial expression and did not dare to speak up,[30] Xin Pi asked: "How did Your Majesty come up with the idea of relocating those households?"
In the past, although Zhao Tuo became king of the Nanyue kingdom and Gongsun Shu declared himself the Son of Heaven, their regimes did not last long.
The Previous Emperor led several campaigns to attack Wu, but there was never a time when he managed to advance beyond the Yangtze River.
The best course of action is to follow Fan Li's strategy by letting our troops rest and recuperate, and allowing the people to live in peace and go about with their normal livelihoods.
We should also follow Guan Zhong's approach and focus on domestic affairs, adopt Zhao Chongguo's tuntian method, and emulate Confucius's style of diplomacy.
[42] At the time, there were two Wei officials – Liu Fang (劉放) and Sun Zi (孫資) – who wielded much influence in the central government as they were highly trusted by Cao Rui.
"[46] After reading Bi Gui's memorial, Cao Rui sought Liu Fang and Sun Zi's opinions.
Xin Pi wrote a memorial to urge Cao Rui to stop the projects: "I heard that Zhuge Liang is actively preparing for war, and that Sun Quan has been purchasing horses from Liaodong.
"[49]Cao Rui replied: "By working on these projects while Eastern Wu and Shu Han have yet to be vanquished, I am providing opportunities for outspoken and fame-seeking people to voice their opinions.
[57][58] In 234, the Battle of Wuzhang Plains took place between Wei and Shu forces, who were respectively led by Sima Yi and Zhuge Liang.
When the situation came to a stalemate, Sima Yi, who held the position of General-in-Chief (大將軍), wrote to Cao Rui to seek permission to engage the enemy.
Later, as the stalemate dragged on, Cao Rui became worried that Sima Yi would defy orders and attack the enemy, so he appointed Xin Pi as military adviser to the General-in-Chief, granted him an imperial sceptre (a symbol of the emperor's authority), and sent him to the frontline to ensure that Sima Yi followed orders and stayed in camp.
[59] The Weilue recorded that Sima Yi wanted to order his troops to attack after the Shu forces goaded and provoked him numerous times.
However, Xin Pi used the imperial sceptre to order them to remain in camp and refrain from engaging the enemy.
[60] After Zhuge Liang died of illness during the standoff, Xin Pi was recalled back to serve as Minister of the Guards (衞尉) again in the central government.
He inherited his father's peerage as the Marquis of Ying District (潁鄉侯) and served as an official in the Wei government.
He rose to the position of Administrator of Henei Commandery (河內郡; around present-day Jiaozuo, Henan) during the Xianxi era (264–265).