Early life and career

Jia Xu was from Guzang County (姑臧縣), Wuwei Commandery (武威郡), which is in present-day Wuwei, Gansu. In his youth, he was unimpressive and unheard of. However, Yan Zhong (閻忠), an official from Hanyang Commandery (漢陽郡; around present-day Gangu County, Gansu), felt that Jia Xu was extraordinary and even remarked that Jia had the brilliance of Zhang Liang and Chen Ping, two famous strategists of the early Western Han dynasty.

Jia Xu was nominated as a xiaolian to serve in the Eastern Han government as a Gentleman Cadet (郎). However, due to illness, he quit his job and went home. On the way back, he was captured by Di rebels at Qian County (汧縣; in present-day Long County, Shaanxi) along with several other travellers. He told the rebels: "I am a maternal grandson of Lord Duan. If you let me live, my family will reward you handsomely." "Lord Duan" referred to Duan Jiong (段熲), who held the position of Grand Commandant (太尉) in the Han imperial court. As Duan Jiong had served for years as a general guarding the Han Empire's western regions, he was well known among the people living in the area. Jia Xu knew that the Di rebels were afraid of Duan Jiong, so he pretended to be Duan Jiong's maternal grandson. As he expected, the rebels treated him respectfully and released him. The other travellers were all killed.

Service under Dong Zhuo

In 189, the warlord Dong Zhuo entered the imperial capital, Luoyang, and took control of the central government. Jia Xu was then serving as the Commandant (都尉) of Pingjin (平津) and an assistant official in the Grand Commandant's office. He was promoted to Colonel Who Attacks Barbarians (討虜校尉) and assigned to the unit led by Dong Zhuo's son-in-law, Niu Fu.

In 192, Dong Zhuo was assassinated by Lü Bu in the imperial capital, Chang'an, while Niu Fu was murdered by his subordinates. The rest of Dong Zhuo's loyalists, including Li Jue, Guo Si and Zhang Ji, became fearful and wanted to disband and return to their respective home commanderies. Jia Xu told them: "I heard that the new government in Chang'an is planning to exterminate everyone from Liang Province. If all of you break up and travel alone, even a tingzhang can arrest you. Why don't you retreat to the west together? There you can gather and reorganise your forces, and then attack Chang'an to avenge Lord Dong. If you succeed, you can make use of imperial authority to conquer the rest of the Empire. If you fail, it's still not too late to escape." Dong Zhuo's loyalists agreed with Jia Xu and did as he suggested. They managed to defeat the new central government in Chang'an led by Lü Bu and Wang Yun, and then took control of the city.

Pei Songzhi, who annotated Jia Xu's biography in the Sanguozhi, strongly criticised Jia Xu for offering this suggestion. He argued that Dong Zhuo's death marked the end of his tyranny and a possible revival of the declining Eastern Han dynasty. However, due to Jia Xu's suggestion, the Han Empire became even more chaotic after Dong Zhuo's death.

Service under Li Jue

When Jia Xu later served as Left Adjunct (左馮翊), Li Jue and Dong Zhuo's loyalists wanted to reward him by making him a marquis, but Jia Xu said, "That suggestion I made was meant to save your lives. What merit have I achieved to deserve a reward?" He declined to accept the marquis title. Later on, when he was nominated to serve as a Supervisor of the Masters of Writing (尚書僕射), he said: "The Supervisor of the Masters of Writing is like a tutor to officials. I don't have a strong reputation so I am afraid I might not be able to convince people that I am suited for this appointment. What will become of the imperial court if I accept this appointment for my personal glory?" He was then assigned to be a Master of Writing (尚書) instead, and was tasked with selecting candidates to serve in the government. Li Jue and the others regarded him highly but were also wary of him. The candidates Jia Xu chose tend to be officials who formerly served in the previous administration. Jia Xu came under some criticisms for his mode of selecting government officials. When there were tensions between Li Jue, Guo Si and Fan Chou, with their respective subordinates urging them to go to war, Jia Xu reprimanded them for their behaviour and tried to persuade them to avoid conflict. They listened to him.

When his mother died, Jia Xu resigned and went home for filial mourning. He was given the honorary position of a Household Counsellor (光祿大夫) by the imperial court. In 195, when conflict broke out between Li Jue and Guo Si in Chang'an, Li invited Jia Xu back to serve as General Who Upholds Righteousness (宣義將軍). Li Jue and his men discussed with Jia Xu their plan to bring Emperor Xian to their camp and use the emperor as a hostage to threaten Guo Si, but Jia Xu said: "No, it isn't right to hold the Emperor hostage." Li Jue refused to listen to him and went ahead. Guo Si, on the other hand, kidnapped Emperor Xian's subjects and held them hostage in his own camp. Zhang Xiu told Jia Xu, "You shouldn't stay here any longer. Why don't you leave?" Jia Xu replied, "I have received grace from the Empire, so I won't betray the Empire's trust in me. If you wish to leave, you can go. I won't leave."

Li Jue used material wealth to tempt thousands of Qiang tribesmen to support him in his struggle against Guo Si. He even promised to give palace women as concubines to the tribal chiefs. When the tribesmen showed up at Chang'an, they asked: "Is the Emperor inside? General Li has promised to give us palace women as concubines. Where are they?" Emperor Xian turned to Jia Xu for help. Jia Xu secretly hosted a banquet for the tribal chiefs, gave them some expensive material gifts, and succeeded in making them leave. Li Jue lost the support of the tribal chiefs. Jia Xu played an important role in resolving the conflict between Li Jue and Guo Si, and in ensuring Emperor Xian's safety during the time. Later, after Emperor Xian escaped from Chang'an, Li Jue led his forces in pursuit and defeated forces led by the emperor's loyalists. He hated certain officials such as Zhao Wen (趙溫), Wang Wei (王偉), Zhou Zhong (周忠) and Rong Shao (榮邵), and wanted to execute them. Jia Xu advised him against it by saying: "They are the Emperor's subjects. How can you harm them?" Li Jue spared them.

Brief service under Duan Wei

After Emperor Xian left Chang'an, Jia Xu gave up his official post and left Li Jue. He heard that the general Duan Wei (段煨), who was from the same commandery as him, was stationed at Huayin County (華陰縣; present-day Huayin, Shaanxi), so he went to Huayin County to join Duan Wei. Jia Xu was well known among Duan Wei's men, so Duan Wei was fearful that Jia Xu would seize the position of leadership from him. He pretended to treat Jia Xu respectfully while secretly keeping a close watch on him. Jia Xu knew that Duan Wei was suspicious of him, and he felt very uneasy.

Around 196, the warlord Zhang Xiu was based in Nanyang Commandery (南陽郡; around present-day Nanyang, Henan). Jia Xu secretly contacted Zhang Xiu and conveyed his intention to join him; Zhang Xiu agreed and sent his men to receive Jia Xu. Before Jia Xu left Duan Wei, someone asked him, "(Duan) Wei treated you generously. Why are you leaving?" Jia Xu replied, "(Duan) Wei is suspicious by nature and he's wary of me. Even though he treats me generously now, I believe he will harm me eventually. However, if I leave now, he will be more than happy to see me gone. If I manage to help him find an external ally, he will treat my family well. (Zhang) Xiu lacks a strategist, so he definitely hopes to have me on his side. By leaving, I can protect myself and my family."

Service under Zhang Xiu

Jia Xu left Duan Wei and headed to Nanyang Commandery, where Zhang Xiu welcomed him and treated him like a family elder. As Jia Xu foresaw, Duan Wei was pleased to see that Jia Xu had not only left, but also helped him gain Zhang Xiu as an ally. Jia Xu urged Zhang Xiu to form an alliance with Liu Biao, the Governor of Jing Province, and went to speak to Liu Biao. Liu Biao treated him like an honoured guest. Jia Xu remarked: "(Liu) Biao has the ability to serve as a Ducal Minister in times of peace. However, he not only lacks foresight, but is also suspicious and indecisive, hence he won't be successful."

Battles against Cao Cao

In 198, the warlord Cao Cao attacked Zhang Xiu again despite having suffered an earlier defeat at the Battle of Wancheng in 197. However, he pulled back his forces after learning that Tian Feng, an adviser to his rival, Yuan Shao, had urged Yuan Shao to attack Xu (許; present-day Xuchang, Henan) while he was away at war with Zhang Xiu. Zhang Xiu wanted to seize the opportunity to launch a counterattack, but Jia Xu warned him not to and predicted that he would be lose the battle. Zhang Xiu ignored him and led his troops to pursue Cao Cao's retreating forces. The result was just like what Jia Xu predicted. When Zhang Xiu came back after his defeat, Jia Xu told him to attack again and predicted that he would win this time. Zhang Xiu said: "I didn't listen to you earlier, which resulted in my defeat. Now that I have lost, why should I attack again?" Jia Xu replied: "Changes have taken place. You'll win if you swiftly attack now." Zhang Xiu heeded Jia Xu's advice and attacked Cao Cao again. He won the battle this time.

Zhang Xiu asked Jia Xu: "When I led my best troops to attack Cao Cao while he was retreating, you predicted I would lose. When I led my troops to attack Cao Cao again just after he defeated me, you predicted I would win. Your predictions turned out to be accurate. But why is it that your predictions seem so counter-intuitive?" Jia Xu replied: "It's easy to understand. General, you may be skilled in warfare, but you are still no match for Cao Cao. When Cao Cao withdrew his forces, I knew he would personally lead his rearguard to cover his retreat. Even though your troops are well-trained, Cao Cao is better than you as a military leader, and his troops are as equally well-trained as yours. Therefore, I knew you would lose. When Cao Cao first attacked you and decided to retreat halfway even though he didn't make any mistakes, I believed something must have happened in his base. After he defeated your pursuing forces, he would lower his guard and hastily retreat. His officers will then take command of the rearguard. They may be brave, but they are no match for you. Therefore, I knew you would win them even though you are leading a group of soldiers who have just been defeated." Zhang Xiu was very impressed with Jia Xu's analysis.

Persuading Zhang Xiu to surrender to Cao Cao

In 199, when Cao Cao and Yuan Shao were about to clash at the Battle of Guandu, Yuan Shao sent a messenger to meet Zhang Xiu and propose an alliance between them against Cao Cao. Zhang Xiu wanted to agree, but Jia Xu, who was beside him, said to Yuan Shao's messenger: "I say 'No, thank you.' to Yuan Benchu. He can't even accommodate his own brother. What makes him think he can accommodate talents from around the Empire?" A shocked Zhang Xiu turned to Jia Xu and asked: "Why do you have to say this? What will become of me now?" Jia Xu replied: "Why don't you submit to Cao Cao?" Zhang Xiu asked: "Yuan Shao is powerful while Cao Cao is weak. Besides, I am also Cao Cao's enemy. What will happen if I submit to him?" Jia Xu replied: "That's why it is better for you to submit to Cao Cao. He controls the Empire in the name of the Emperor. This is the first reason why you should submit to him. Yuan Shao is militarily more powerful. You have less troops than him, so even if you join him, he won't regard you highly. Cao Cao has less troops. If you join him, he'll be delighted. This is the second reason why you should submit to him. A man who aspires to become a great ruler will be more willing to put aside personal enmities and make his virtues known to people. This is the third reason why you should submit to Cao Cao. I hope you won't have any more doubts." Zhang Xiu heeded Jia Xu's advice and led his forces to surrender to and join Cao Cao.

Service under Cao Cao

Cao Cao was very pleased to see Jia Xu. He held Jia Xu's hand and said: "You are the person who helps to make my trustworthiness known throughout the Empire." Jia Xu was appointed Bearer of the Mace (執金吾) and enfeoffed as a Marquis of a Chief Village (都亭侯). He was later promoted to the position of Governor (牧) of Ji Province. As Ji Province was still under Yuan Shao's control then, Jia Xu served as a military adviser to Cao Cao, who then held the appointment of Minister of Works (司空).

Advising Cao Cao during the Battle of Guandu

During the Battle of Guandu, when his supplies were running out after a prolonged stalemate against Yuan Shao, Cao Cao sought advice from Jia Xu, who said: "My lord, you're wiser than (Yuan) Shao, braver than (Yuan) Shao, better at managing people than (Yuan) Shao, and more decisive than (Yuan) Shao. You have these four strengths, but the reason why you are unable to defeat him after six months is because you have been focusing too much on defence. You should be decisive when the opportunity arises, and victory will follow soon." Cao Cao replied, "Fine." He then led his forces to attack Yuan Shao's camps, which were spread out a distance of over 30 li, and destroyed them. Cao Cao won a decisive victory over Yuan Shao at the Battle of Guandu and subsequently conquered the rest of Yuan's territories north of the Yellow River.

Advising Cao Cao against attacking Sun Quan

When Cao Cao was appointed as the Governor of Ji Province after pacifying northern China, Jia Xu was reassigned to be a Palace Counsellor (太中大夫) instead. In 208, after Cao Cao had annexed Jing Province, he planned to press on and attack the territories in Jiangdong controlled by the warlord Sun Quan. Jia Xu advised him against it and said: "My lord, you have defeated the Yuans and now you have taken Jing Province. Your name spreads throughout the Empire and your military is very strong. If you follow in the footsteps of the Chu state by attracting talents to serve in the government and by improving the lives of the people, you won't need to resort to force to subdue the Jiangdong territories. They will be submit to you on their own." Cao Cao ignored Jia Xu and proceeded to attack Jiangdong. He lost the decisive Battle of Red Cliffs against the allied forces of Sun Quan and Liu Bei later that year.

Pei Songzhi, who annotated Jia Xu's biography in the Sanguozhi, argued that Jia Xu's advice to Cao Cao was inappropriate. He pointed out that Cao Cao's territories lacked the stability necessary for Cao Cao to do as Jia Xu advised – focus on economic development in Jing Province. Moreover, Cao Cao had to deal with the external threats posed by warlords such as Han Sui and Ma Chao in the northwest. Pei Songzhi noted that Jing Province was highly unstable and would not remain under Cao Cao's control for long, because of the polarising effects of the presences of Liu Bei and Sun Quan in the region. He pointed out that during the Battle of Jiangling in 208, Cao Cao's general Cao Ren still lost Jiangling Commandery to Sun Quan and Liu Bei's forces despite his best efforts at defending it. Pei Songzhi thus concluded that it was impossible for Cao Cao to focus on economic development in Jing Province, given how unstable the region was, therefore Jia Xu's advice was inappropriate. He argued that Cao Cao made a right choice to attack Jiangdong at the right time, when he had resources for naval warfare acquired from his recent annexation of Jing Province. He also mentioned that Cao Cao's defeat at the Battle of Red Cliffs was not due to miscalculation or poor planning, but because of uncontrollable factors such as the plague which affected his troops and the winds which fanned the fire that destroyed his naval fleet.

Advising Cao Cao during the Battle of Tong Pass

In 211, Cao Cao engaged a coalition of northwestern warlords led by Han Sui and Ma Chao at the Battle of Tong Pass. Ma Chao and others agreed to make peace with Cao Cao on two conditions. Firstly, Cao Cao had to give up the northwestern territories to them. Secondly, Cao Cao had to grant them official titles. Jia Xu suggested that Cao Cao pretend to agree to their terms, and then try to sow discord among them. Cao Cao heeded Jia Xu's advice. When internal conflict broke out between Han Sui and Ma Chao, Cao Cao took advantage of the situation to attack them and achieved victory.

Role in the succession struggle between Cao Pi and Cao Zhi

Sometime between 211 and 217, a power struggle broke out between two of Cao Cao's sons over the succession to the "King of Wei" (魏王), the nominal vassal king title held by their father. One of them was Cao Pi, Cao Cao's oldest surviving son, who held the appointment of General of the Household for All Purposes (五官中郎將). The other was Cao Zhi, who held the title "Marquis of Linzi" (臨菑侯) and was famous for his literary talent. Each of them had a faction supporting him.

Cao Pi sent a messenger to meet Jia Xu and seek his advice on how to consolidate his position. Jia Xu replied: "I hope you will behave in a virtuous and humble manner, perform your duties faithfully, and be a filial son. That is all." Cao Pi took Jia Xu's advice very seriously and did as he was told.

Cao Cao faced a dilemma on choosing between his two sons so he consulted Jia Xu, who refused to give an answer. Cao Cao asked him: "Why don't you give an answer?" Jia Xu replied: "I am still thinking about something, so I can't give an answer yet." Cao Cao asked, "What are you thinking of?" Jia Xu replied, "I am thinking of Yuan Benchu, Liu Jingsheng, and their sons." Cao Cao laughed, made up his mind, and designated Cao Pi as his heir apparent.

Jia Xu was aware that he had not served under Cao Cao for as long as many of his colleagues. He foresaw that he might incur the jealousy and suspicions of others, hence he maintained a very low profile and distanced himself from his colleagues outside of the workplace. He also ensured that his children did not marry people from influential families. He earned the respect and admiration of many strategists and advisers.

Service under Cao Pi

In 220, Cao Pi forced Emperor Xian to abdicate the throne to him, thus ending the Han dynasty. He then established the state of Wei with himself as its first emperor. After ascending the throne, Cao Pi appointed Jia Xu as Grand Commandant (太尉) and promoted him from a Marquis of a Chief Village to the Marquis of Weishou District (魏壽鄉侯), with a marquisate of 800 taxable households. Jia Xu's promotion was allegedly an expression of gratitude from Cao Pi, who wanted to thank him for helping him seize the succession years ago. Sun Quan laughed when he heard that Cao Pi had appointed Jia Xu as his Grand Commandant.

Advising Cao Pi against attacking Eastern Wu

Sometime between 220 and 223, Cao Pi wanted to attack and conquer Wei's two rival states, Wu and Shu. He consulted Jia Xu on which of the two he should attack first.

Jia Xu replied: "Before you can conquer others, you have to build up military power first. Before you can establish a power base, you have to promote civil culture. Your Majesty has received the Mandate of Heaven in a timely fashion and now rules over the Empire. If you can promote civil culture while waiting for an opportunity to strike, it won't be difficult for you to conquer your enemies. Wu and Shu may be small and insignificant states, but they are shielded by natural geographical barriers such as mountains and rivers. Liu Bei has talent and great ambition; Zhuge Liang excels in statecraft; Sun Quan understands trends and sees through deception; Lu Yi assesses military power very well. They control geographically advantageous locations, and have set up defences at strategic points and the rivers and lakes. It is not easy to plan an attack. According to military strategy, you should gain the upper hand first before actually fighting a battle. You should assess the enemy's strength, and then decide which generals to send into battle. This is to ensure that you don't miscalculate. From my observation, none of our officials are capable of rivalling (Liu) Bei and (Sun) Quan. Even though you may fight a war with the prestige of an Emperor, you can't win without making significant losses. In the past, Shun ordered his troops to brandish their weapons to scare the Youmiao into submission. As of now, I think it is better to focus on civil affairs first before military affairs."

Cao Pi refused to listen to Jia Xu. In 223, Wei sustained heavy losses at the Battle of Jiangling against Wu.

Death

Jia Xu died on 11 August 223 at the age of 77 (by East Asian age reckoning). He was given the posthumous title "Marquis Su" (肅侯).

Family and descendants

According to the Xin Tang Shu, Jia Xu descended from the royal family of the Zhou dynasty. His ancestor was Gongming (公明), the youngest son of Shuyu (a son of King Wu of Zhou). Gongming was enfeoffed by King Kang of Zhou as the Count of Jia (賈伯) and given the lands around Linfen as his fief, which was named "Jia". His descendants adopted "Jia" as their family name. Jia Yi, a notable scholar-politician who lived in the Western Han dynasty, was an ancestor of Jia Xu. Jia Xu's father, Jia Gong (賈龔), served as a General of Light Cavalry (輕騎將軍) in the Eastern Han dynasty and moved his residence to Wuwei Commandery, where Jia Xu was born. Jia Xu had an elder brother, Jia Cai (賈綵).

Jia Xu had at least three sons. His eldest son, Jia Mu (賈穆), was a Chief Commandant of Escorting Cavalry (駙馬都尉). After Jia Xu's death, Jia Mu inherited his father's marquis title, Marquis of Weishou District (魏壽鄉侯). He also served as the Administrator (太守) of various commanderies. Jia Xu's youngest son, Jia Fang (賈訪), was given a marquis title and 200 taxable households around the same time as when Jia Xu was enfeoffed as the Marquis of Weishou District. According to the Xin Tang Shu, Jia Xu had a son, Jia Ji (賈璣), who also served as a Chief Commandant of Escorting Cavalry like Jia Mu, and held the title of a Secondary Marquis (關內侯). Jia Ji is not mentioned in Jia Xu's official biography in the Sanguozhi.

When Jia Mu died, his marquis title was passed on to his son, Jia Mo (賈模). According to the Shiyu (世語), Jia Mo served as a Regular Mounted Attendant (散騎常侍) and General Who Protects the Army (護軍將軍) during the reign of Emperor Hui in the Western Jin dynasty. Jia Mo had two sons, Jia Yin (賈胤) and Jia Kan (賈龕). Jia Yin, Jia Kan, and their cousin Jia Pi, served in the Jin government and held high official positions.

Writings

Jia Xu annotated the military treatise Wuzi and wrote another military text called Wu Sun Zi Sanshi'er Lei Jing (吳孫子三十二壘經). He also created a copy of Sun Tzu's The Art of War.

Appraisal

Chen Shou, who wrote Jia Xu's biography in the Sanguozhi, appraised him as follows: "Xun You and Jia Xu were very detailed in their strategising and had never miscalculated before. However, in terms of adaptability and flexibility, they were second to (Zhang) Liang and (Chen) Ping."

Pei Songzhi, who annotated the Sanguozhi, disagreed with Chen Shou. He believed that biographies should be categorised in the same volume on the basis of similarities. He argued that Jia Xu's biography should be in the same volume as the biographies of Cheng Yu and Guo Jia rather than in the same volume as the biographies of Xun Yu and Xun You. In Pei Songzhi's opinion, Jia Xu was more similar to the former two than to the latter two. Pei Songzhi even remarked, "The difference between the moral characters of Xun You and Jia Xu is like the difference between moonlight and candlelight. Both give off light, but they are fundamentally different." He also criticised Chen Shou for appraising Xun You and Jia Xu in the same sentence instead of appraising them separately.

In popular culture

Jia Xu was first introduced as a playable character in the seventh instalment of Koei's Dynasty Warriors video game series.

生平

儒學家世

賈詡祖上乃是西漢長沙王太傅賈誼，賈誼師從西漢宰相張蒼，張蒼師從儒學三巨頭之一的荀子，張蒼乃是荀子的關門弟子，得意門生。而張蒼的侄兒就是西漢趙王張耳，而巧的是前涼張軌就是張耳的後裔，後世居于武威郡。而賈氏一脈也和西漢張氏如出一轍，世居于武威郡。武威郡賈氏一族可謂正統的儒學豪門。

少年經歷

賈詡生于147年。賈詡年輕時聲名並不顯赫，唯獨名士閻忠認為他與眾不同，說他有張良、陳平那樣的智慧。在一次旅途中遭遇氐族的叛軍，身旁數十人皆被擒住，賈詡發揮機智，辯稱自己是太尉段熲外孫，氐人信其言，於是獲釋。史稱賈詡此舉是：「權以濟事，咸此類也」（《三國志·魏書·賈詡傳》）。

涼州軍劫天子|文和亂武

後來成為董卓部下，以太尉掾為平津都尉，後升為討虜校尉，在牛輔帳下。在董卓討伐戰期間，一度和李傕、郭汜、張濟等人一同擊敗孫堅。董卓滅亡後，牛輔亦已死去，司徒王允清算董卓餘黨。當時李傕、郭汜等人心懷不安，都打算各自逃亡，賈詡則勸諫李傕：「如果就這麼逃跑，只需一個亭長就能將我們一網打盡，現在必須回頭攻打長安。」李傕聽從賈詡建議，與郭汜、樊稠、張濟等聚集兵力回攻長安，駐守長安的王允不敵，被李傕殺死；同為守將的呂布則逃亡至關東。

李傕、郭汜、樊稠等人掌權後，任命賈詡為左馮翊尹，還要封侯。賈詡堅決推辭才作罷。改任為尚書典選。

李傕、郭汜在占領長安後，起初還算和氣，不久互相猜疑，終于關係破裂，相互攻殺，關中地區被鬧得荒無人煙。漢獻帝為躲避災難，率群臣和衛兵逃往雒陽。賈詡曾訓斥李傕、郭汜兩人的戰爭給人民帶來的災難，但兩人表面上接受賈詡的批評，但並沒有停止相互攻殺。於是賈詡離間李傕雇用的羌、胡傭兵使之離去，並且協助漢獻帝離開長安，同時保護受李傕、郭汜迫害的大臣。

籌策志略

天子後要求回雒陽，命段煨等人護送，因段煨與賈詡同郡，賈詡便棄李傕而跟隨段煨。但因賈詡名氣實在太大，段煨怕自己的地位不保，密謀殺害賈詡，為賈詡識破。賈詡私下結識張繡，張繡迎接賈詡。賈詡屢獻妙計，助張繡叛曹（起因曹操將張繡叔母佔為己有），曹操大將典韋，長子曹昂，侄子曹安民戰死；建議張繡跟劉表議和，並多次挫敗曹操，使曹操攻不下宛城。在官渡之戰時，勸張繡向曹操投降而非袁紹，使得曹操避免兩面受敵的絕境，備受曹操之敬重。封賈詡為執金吾，封都亭侯，遷冀州州牧。

凝析踐局

200年，曹操與袁紹戰於官渡，後曹軍軍糧將盡。曹操便問計於賈詡，賈詡說：「公明勝紹，勇勝紹，用人勝紹，決機勝紹，有此四勝而半年不定者，但顧萬全故也。必決其機，須臾可定也。」（《三國志·魏書·賈詡傳》）曹操稱善，而後許攸投曹獻計，曹操突襲袁紹烏巢糧倉，大破之，致袁紹潰敗。曹操戰勝後自領冀州牧，封賈詡為太中大夫。赤壁之戰前，認為應安撫百姓而不應勞師動眾討江東，曹操不聽，結果受到嚴重的挫敗。

曹操後與韓遂、馬超戰於渭南，馬超等人有割地以和的意思，並以兒子為人質。賈詡認為可以裝作答應，曹操又問賈詡計策，賈詡說：「以間離之。」，曹操承用賈詡的計謀，隨即破韓遂、馬超。

權明濟事

曹操當時未立世子，曹丕為五官將，而臨菑侯曹植才名方盛，曹丕派人求計于賈詡，賈詡說：「願將軍恢崇德度，躬素士之業，朝夕孜孜，不違子道。如此而已」，曹丕從其言，深自砥礪。後曹操為立世子之事屏退左右獨問賈詡，賈詡閉口不答，曹操說：「與卿言而不答，何也？」賈詡說：「屬適有所思，故不即對耳。」曹操說：「何思？」賈詡說：「思袁本初、劉景升父子也」。（袁紹、劉表兩人都是想廢長立幼導致兒子之間的衝突，成為失敗的部分原因。）曹操聞言大笑會意，建安二十二年（217年）立曹丕為世子。

黃初元年（220年），曹丕篡位自立，為報賈詡之恩，封賈詡為太尉，進爵魏壽鄉侯，增食邑三百，前後共八百戶。又分食邑二百，封幼子賈訪為列侯。以長子賈穆為駙馬都尉。

黃初四年（223年）三月，曹丕首征東吳，以失敗而告終。戰前，曹丕問計于賈詡：「吾欲伐不從命以一天下，吳、蜀何先？」賈詡說：「攻取者先兵權，建本者尚德化。陛下應期受禪，撫臨率土，若綏之以文德而俟其變，則平之不難矣。吳、蜀雖蕞爾小國，依阻山水，劉備有雄才，諸葛亮善治國，孫權識虛實，陸遜見兵勢，據險守要，泛舟江湖，皆難卒謀也。用兵之道，先勝後戰，量敵論將，故舉無遺策。臣竊料群臣，無備、權對，雖以天威臨之，未見萬全之勢也。昔舜舞幹戚而有苗服，臣以為當今宜先文後武」（《三國志·魏書·賈詡傳》）。曹丕不納，果然無功而反。

明哲保身

賈詡認為自己非曹操舊臣，卻策謀深長，所以怕曹操猜嫌。于是採取自保策略，「闔門自守，退無私交，男女嫁娶，不結高門，天下之論智計者歸之」（《三國志·魏書·賈詡傳》）。

黃初四年（223年）六月甲申日，賈詡去世，終年77歲，謚肅侯，長子賈穆嗣。

兵法與經學

據《隋書·經籍志》「兵」篇載，賈詡曾鈔錄《孫子兵法》一卷；又據《新唐書·藝文志》「兵書類」載，賈詡曾為《吳子兵法》作注。可見賈詡對兵家的經典頗有研究。

藝術形象

三國演義

在中國著名歷史演義章回小說《三國演義》中，賈詡亦有耀眼的表現。他初登場於第九回「除暴凶呂布助司徒　犯長安李傕聽賈詡」，以西涼謀士身分從屬於董卓集團餘黨李傕、郭汜陣營。當時董卓已死，李傕等四人上表求赦不果，正欲各自逃難，賈詡建議他們召集西涼人馬入京攻打呂布，結果成功驅逐呂布。可是李傕等人卻擅權暴虐，欺凌帝上，甚於董卓。第十回中，西涼馬騰、韓遂東征勤王，賈詡勸李傕深溝高壘，不與接戰，待西涼兵糧盡退兵加以追擊，結果亦大敗馬、韓。李、郭掌權期間，賈詡一直引導他們安撫天下，徵用賢能，朝廷稍微有所恢復。

第十三回，李、郭失和，互相攻討，一劫天子一劫公卿，長安大亂，賈詡與左靈被李傕任命負責監押帝後車駕。但賈詡當時仍心繫漢室，答應獻帝盡力阻止李傕暴行。李傕要殺帝使皇甫酈時，亦賴賈詡等力勸才得免。其後賈詡暗地勸喻李傕陣中的羌兵解散，又設計建議獻帝以重爵加封李傕，讓其暴露自身貪婪信巫的缺點，李傕軍中因而士卒離心。第十四回曹操舉兵勤王，賈詡勸李傕投降求赦，李傕怒欲斬之，賈詡於是離開李傕回到家鄉武威。

第十六回，正當曹操與呂布鏖戰時，南方傳來訊息指張濟攻南陽中流矢而死，其侄張繡繼統其軍，佔據宛城，並用賈詡當謀士，與劉表結連，成為曹操南方的大患。於是曹操放下東邊戰線，趕赴南方親征張繡。大軍壓境，賈詡又建議張繡投降曹操，張繡亦願意接受。可是曹操因好色與張繡嬸母鄒氏共寢辱及張繡，張繡怒不可當，賈詡唯有獻計讓張繡引軍圍攻沒有戒備的曹操，此役令曹操幾乎失陷，並折損了大將典韋、長子曹昂及侄兒曹安民等。

第十八回回目以賈詡為主，是為「賈文和料敵決勝　夏侯惇拔矢啖睛」。曹操擊敗袁術後，再議征討張繡。賈詡以將計就計之法，再次令曹操中伏，大損五萬兵馬，將領于禁、呂虔亦受戰傷。後來曹操退兵，張繡、劉表議欲追襲，賈詡認為必敗，果如其言；然而賈詡又勸二人再次起兵追襲，張繡聽從其計，結果大勝而還。此回盡顯賈詡料事如神的本領。直至第二十三回，袁紹、曹操分別遣使勸張繡歸順。張繡聽從賈詡的建議，降服曹操。賈詡被曹操封為執金吾使。官渡之戰中，賈詡亦有隨軍出征，多為曹操守寨。

第五十九回，馬超興兵討曹操，賈詡隨軍西征，並獻離間計，致抹書予韓遂令馬超疑惑，使馬超與韓遂失和相攻，曹軍因而得勝。第六十七回，曹操征張魯，欲得猛將龐德歸順，賈詡獻計透過賄賂楊松，離間龐德與張魯之間的關係，亦成功令龐德降曹。

第六十八回，曹操議立嗣子，賈詡屬意曹丕，故當曹操問及其意見時，賈詡淡淡地提到袁紹、劉表二人，讓曹操聯想到二人立幼廢長終致覆滅的故事，然後決意立曹丕為後嗣。第七十八回，曹操欲築建始殿，賈詡推薦雒陽良匠蘇越；曹操夜夢三馬同槽，問於賈詡，賈詡為其釋慮。曹操臨終託孤，賈詡亦是顧命大臣之一。曹丕繼位後，封賈詡為太尉，位列三公。第八十回，曹丕篡漢，賈詡建議曹丕築受禪台以避後世之議，又勸獻帝詔書禪位。第八十二回，孫權遣趙咨為使，向曹丕稱臣賓服，使者到魏，亦先見太尉賈詡，可見賈詡於朝中地位超然。第八十五回，曹丕乘孫劉鏖兵夷陵，於是遣三路兵馬暗襲東吳，賈詡勸阻，曹丕不聽，招致大敗。最後，第八十六回，小說正式交代賈詡之死。

賈詡在演義中由第九回橫跨至第八十六回，形象突出，計無不中，甚至曾令善於用兵的曹操幾度敗績。其所從屬勢力頗多，先隨李傕，再隨張繡，最後事曹操曹丕兩代。加上他曾助曹丕篡漢，其形象不算十分正面。可是即使賈詡曾助李傕、曹魏這些在《三國演義》形象比較負面的勢力，他的才能仍備受肯定。而且不論是李傕、張繡，還是曹操、曹丕，都將賈詡此人視為心腹。可見其人善於交際，亦深曉亂世自保之術。

影視形象

• 1994年電視劇《三國演義》：李緒良、徐永亮飾演賈詡

• 1994年歌仔戲《洛神》：左一成飾演賈詡

• 2002年香港無線電視台電視劇《洛神》：王維德飾演賈詡

• 2004年電視劇《武聖關公》：熊文權飾演賈詡

• 2013年電視劇《新洛神》：邢傑風飾演賈詡

• 2013年電視劇《曹操》：孫祺飾演賈詡

• 2018年電視劇《三國機密》：舒耀瑄飾演賈詡

動漫遊戲

• 真·三國無雙系列 / 無雙OROCHI系列（光榮公司開發，石川英郎配音）

• 三國演義

• 《火鳳燎原》（陳某）:設定是司馬徽的弟子，名聞天下的軍師集團「水鏡八奇」中的「三奇」，和李儒是義兄弟，曾使計使先敗李肅、再使計令呂布兩次大敗，後因李傕、郭汜之猜忌而離開長安而投張繡(實質上暗助曹操)，在宛城之役因龐統而一度失勢，在徐州討呂布時正式和張繡投曹，在官渡之戰中曾打敗高覽，在赤壁之戰中在水上曾和周瑜交手，赤壁之戰後曾與龐統聯手密謀襲殺周瑜，以維持三分平衡，為確認周瑜身死親入其所佈的火陣，憑藉馬鈞的指南車全身而退。

• 《蒼天航路》（王欣太）:賈詡獻計助張繡暗殺曹操，結果失敗但也使典韋、曹昂、曹安民皆在宛城戰死，之後與張繡投降曹操。在曹操軍中自稱最殘忍刻薄的軍師。

家庭

據《新唐書·宰相世系表》記載，賈詡是西漢時代文豪賈誼的末裔。據《魏晉世語》，賈氏一族於晉惠帝時皆至大官，於晉初時尤為顯貴。

父祖

• 賈誼，賈詡先祖，西漢著名文學家。

• 賈秀玉，賈詡曾祖父，東漢武威太守。

• 賈衍，賈詡祖父，東漢兗州刺史。

• 賈龔，賈詡之父，任輕騎將軍，徙居武威。

(賈龔應為賈詡祖父，根據《元和姓纂》卷七長樂賈氏：「漢長沙王太傅賈誼，洛陽人，十代孫龔，居武威。龔孫詡，魏太尉……」)

兄

• 賈綵，賈詡之兄。

子孫

• 賈穆，賈詡的長子，為駙馬都尉、歷位郡守，承繼賈詡的爵位。

　• 賈模，賈穆之長子，賈詡之長孫，承繼賈穆的爵位，晉惠帝時為散騎常侍，護軍將軍。

　　• 賈胤，賈模子，仕晉惠帝，乃惠帝於太子時之近侍。

　　• 賈龕，賈模之子，胤弟，仕晉惠帝，曾任秦國內史、秦州刺史。

　• 賈疋，賈模從弟，仕晉惠帝及晉懷帝，累官至驃騎將軍、雍州刺史、封酒泉公。

• 賈訪，賈詡之子，分得父親八百戶食邑中二百戶，而受封列侯。

• 賈璣，賈詡之子，魏駙馬都尉、關內侯，後徙居長樂。

　• 賈通，賈璣之子，任侍中、車騎大將軍。

　　• 賈仲安，賈通之子。

　　• 賈仲謀，賈通之子。

　　• 賈仲達，賈通之子，晉潁川太守。

　• 賈延，賈璣之子。

評價

• 《三國志·賈詡傳》：「詡實非段甥，權以濟事，咸此類也。」「詡自以非太祖舊臣，而策謀深長……天下之論智計者歸之。」

• 曹操：「使我信重於天下者，子也。」（《三國志·魏書·荀彧荀攸賈詡傳第十》）

• 閻忠：「詡有良、平之奇。」（《三國志·魏書·荀彧荀攸賈詡傳第十》）

• 《三國志》作者陳壽評曰：「荀彧清秀通雅，有王佐之風，然機鑒先識，未能充其志也。荀攸、賈詡，庶乎算無遺策，經達權變，其良、平之亞歟！」

• 《三國志》裴松之評註：「臣松之以為列傳之體，以事類相從。張子房青雲之士，誠非陳平之倫。然漢之謀臣，良、平而已。若不共列，則餘無所附，故前史合之，蓋其宜也。魏氏如詡之儔，其比幸多，詡不編程、郭之篇，而與二荀並列；失其類矣。且攸、詡之為人，其猶夜光之與蒸燭乎！其照雖均，質則異焉。今荀、賈之評，共同一稱，尤失區別之宜也。」又註：「夫仁功難著，而亂源易成，是故有禍機一發而殃流百世者矣。當是時，元惡既梟，天地始開，致使厲階重結，大梗殷流，邦國遘殄悴之哀，黎民嬰周餘之酷，豈不由賈詡片言乎？詡之罪也，一何大哉！自古兆亂，未有如此之甚。」

• 《三國志》裴松之評注引荀勗別傳載：「三公具瞻所歸，不可用非其人。昔魏文帝用賈詡為三公，孫權笑之。」

• 《周書》作者令狐德棻等評王雄時提到：「周瑜赤壁之謀，賈詡烏巢之策，何能以尚。一言興邦，斯近之矣。」

• 《唐會要》：「魏晉以賈詡之籌策、賈逵之忠壯、張既之政能、程昱之智勇、顧雍之密重、王渾之器量、劉惔之鑑裁、庾翼之志略，彼八君子者。」

• 朱敬則：「神人無功，達人無跡。張子房元機孤映，清識獨流。踐若發機，應同急箭；優遊澹泊，神交太虛，非諸人所及也。至若陳平、荀彧、賈詡、荀攸、程昱、郭嘉、田豐、沮授、崔浩、張賓等，可謂天下之菁英。帷幄之至妙，中權合變，因敗為功，爰自秦漢，訖於周隋。」（《全唐文·卷一百七十一》）

• 楊炯：「孝通神明，忠定社稷。馬伏波來游二帝，晏平仲能事百君。在魏則賈詡、荀攸，在周則太顛閎夭。」（《後周青州刺史齊貞公宇文公神道碑》）「攻城野戰，張飛、關羽；奇策密謀，荀攸、賈詡。」（《瀘川都督王湛神道碑》）

• 李嶠：「賈文和之揣君，酈食其之觀將：翔而後集，可謂明也。」（《攀龍台碑》）

• 李翰：「陸玩無人，賈詡非次。」（《蒙求集注》）

• 白居易：「天下論智計並歸賈氏也。」（《永樂大典殘卷·卷一萬三千四百九十四》）

• 何去非：「『百里而爭利者蹶上將』，孫臏所以殺龐涓也，趙奢犯之而破秦軍，賈詡犯之而破叛羌。……賈詡策張繡以精兵追退軍而敗，以敗軍擊勝卒而勝。……凡此者，皆非法之所得膠而書之所能教也。然而，善者用之，其巧如是。」（《何博士備論》）

• 蘇轍：「公不用其計，以兵入吳境，遂敗于赤壁。夫詡之所以說曹公，則李左車之所以說淮陰侯，使乘破趙之勢，傳檄以下燕者也。方是時，孫氏之據江東已三世矣。國險而民附，賢才為用，諸葛孔明以為可與為援而不可圖。而曹公以劉琮待之，欲一舉而下之，難哉！使公誠用詡言，端坐荊州，使辯士持尺書結好于吳。吳知公無併吞之心，雖未即降，而其不以幹戈相向者可必也。」（《欒城後集·卷九》）

• 陳亮：「漢室再亂于賈詡，終于董昭。」（《龍川集》）

• 蕭常：「董卓，國之賊，天下所共仇，而詡為之報怨。東京之亡禍，根于此。及辭李傕尚書之命，則以朝廷為解，是欲以虛辭蓋實，惡將誰欺邪？」（《蕭氏續後漢書》）

• 章如愚：「至于三國，各自據其土而成鼎峙之勢，亦諸人之力也。故在魏，則荀攸、賈詡之算無遺策，郭嘉、劉曄之才策謀畧，管寧之淵雅高尚，毛玠之典選清正；……皆一時之人傑也。」（《山堂考索》）

• 劉祁：「已而諸豪割據，士大夫各欲擇主立功名，如荀攸、賈詡、程昱、郭嘉、諸葛亮、龐統、魯肅、周瑜之徒，爭以智能自效。」（《歸潛志》）

• 王義山：「某仰惟某官學通六藝，忠貫三精，其謀略則荀攸、賈詡之密，其經濟則周瑜、魯肅之英，其吟嘯則謝安、庾亮之雅，其牧御則羊祜、陸遜之仁。」（《稼村類稿》）

• 郝經：「當是之時，魏有荀彧、荀攸、賈詡、程昱、郭嘉、董昭、劉曄、蔣濟、司馬懿為之謀，吳有張昭、周瑜、魯肅、呂蒙、陸遜運其籌。」（《續後漢書》）

• 陳普：「崩奔堯後一孤兒，跖狗成群共肆欺。賈詡未設曹操日，自為漢賊已多時。」（《全宋詩》）

• 袁宏道：「投身刀戟之林，瀕死不悔，不盡其用不止者，張子房、荀文若、賈詡之流是也。」（《袁中郞全集之袁中郞文鈔》）

• 朱明鎬：「賈、荀合傳，尤為不倫，賈詡為傕、汜謀主，身代董卓，報仇元兇，甫夷逆禍重結，致使行在兩辱，郎官採穭，閱《獻帝本紀》，髪恆上衝，則賊漢者文和，忠漢者文若，忠逆同區，何以垂訓。」（《史糾·卷一》）

• 王夫之：「迨于子桓之世，賈詡、辛毗、劉嘩、孫資皆坐照千里之外，而持之也定。」（《讀通鑑論·卷十》）

• 韓慕廬：「文和周旋群雄，晚歸太祖。惟其智放沈密，而機速過人，故能不受牢籠。」（《三國志集解》）

• 王鳴盛：「賈詡地望無可言，然觀其處父子之間，勉曹丕以孝，答曹操慎忠，則尚優于諸人，離之此而合之彼，其例密矣。」（《十七史商榷》）

• 何千里：「詡之識略，實蓋一時。」（《三國志集解》）

• 何焯：「養威持勝之善謀。」（《三國志集解》）

• 王士禛：「余素不喜李贄之學，其《藏書》、《續藏書》未嘗寓目。近偶觀之，其最害道者莫如《論狂狷》一篇。…若以李斯、桑弘羊、呂不韋、李園、賈詡、董昭為名臣，溫嶠為逆賊，所謂好惡拂人之性者也。」（《古夫于亭雜錄》）

• 獨孤微生：「荀文若、周公瑾、陳元龍、賈文和之流皆一時之魁奇俊傑也。」（《泊齋別錄·任幼庵七十壽序戊辰》）

• 易中天：「賈詡能在亂世中審時度勢，自己是活得時間最長的，還保全了家人。這才是真正的大智慧，賈詡可能是三國時期最聰明的人。」（《易中天品三國之鬼使神差》）