《孫子註解》Vol. 11

Sunzi's Art of War describes nine types of terrain in military operations: dispersive ground (散地), light ground (轻地), contentious ground (争地), open ground (交地), focal ground (衢地), heavy ground (重地), difficult ground (圯地), encircled ground (围地), and death ground (死地). These nine classifications were confirmed by commentators like Cao Cao.

"Dispersive ground" refers to battlefields within one's own territory. Cao Cao explains that soldiers become emotionally attached to their homeland and may easily desert when fighting close to home. Li Quan adds that troops dependent on native soil and concerned for their families tend to scatter when pressed hard. Du Mu observes that in such terrain, soldiers lack the resolve to fight to the death since retreat means returning home. Du You notes that when fighting on home soil, troops become distracted and prone to disintegration.

King Wu once asked Sunzi: "If soldiers become homesick and shouldn't fight on dispersive ground, should we simply defend? What if the enemy attacks our towns, plunders our fields, blocks our roads, then strikes when we're vulnerable?" Sunzi replied: "When enemies penetrate deep into our heartland with cities at their back, their troops regard the army as home and fight single-mindedly. But our soldiers, comfortable in their homeland, lack desperate resolve. In such cases, we must mobilize civilians, stockpile supplies, fortify defenses, and dispatch light troops to sever enemy supply lines. Only when the enemy lacks provisions, finds nothing to plunder, and grows famished should we lure them into battle for victory. For open-field combat, we must rely on treacherous terrain for ambushes—when no such terrain exists, we move covertly."

(Note: The "dispersive ground" and other terrain types are classical military geographic terms denoting areas with different strategic values)

This passage discusses strategies for handling two types of battlefield situations in ancient military tactics: "light terrain" (qindi) and "contested terrain" (zhengdi).

Regarding "light terrain" (areas just inside enemy borders): When troops first enter shallow enemy territory, soldiers tend to become homesick and morale easily collapses. Historical examples like the Yun state's attack on Chu demonstrate this - because their forces were too close to home, they lacked fighting spirit and were defeated.

Military strategists like Cao Cao emphasized special precautions for such terrain: Burn bridges and boats to cut off retreat; avoid rash attacks on major cities while creating diversions; send elite cavalry first to seize livestock and provisions to boost morale with visible spoils; set ambushes along key routes - engage if enemies approach, withdraw quickly if they don't. When King Wu asked Sunzi about such situations, Sunzi advised deploying elite troops at critical junctions - if enemies pursue during withdrawal, spring the ambush.

Concerning "contested terrain" (strategically vital areas both sides fight for): Whoever occupies these first gains advantage. As the strategist Weiliaozi noted, dividing troops to guard multiple routes risks desertion among those forced northward. The solution is to trick enemies into dividing their forces while concentrating ours to seize key positions.

The core principle: In border areas, fight quickly before homesickness sets in; at strategic points, seize initiative through early occupation. These strategies emphasize adapting tactics to terrain while prioritizing psychological factors affecting morale.

Cao Cao believed that in strategically vital terrain, a smaller force could defeat a larger one, and weaker troops could overcome stronger opponents. Li Quan explained that this demonstrates the tactical advantage of controlling critical passes and seizing commanding positions—whoever first occupies such "contested ground" (strategically indispensable locations) gains victory.

Du Mu illustrated this principle with historical examples: When Former Qin’s Fu Jian sent his general Lü Guang to campaign in the Western Regions, later, after Fu Jian’s defeat, Lü Guang marched back. Liang Xi, the governor of Liangzhou, sought to intercept him. Yang Han, the governor of Gaochang, advised: "Lü Guang has just pacified the Western Regions—his morale is high, and his momentum is unstoppable. But the shifting sands create treacherous terrain. If we first secure the strategic pass at Gaowu Valley and cut off their water supply, they will collapse from thirst without a fight. Even if Gaowu seems too distant, we should at least hold the Yiwu Pass." Yet Liang Xi ignored this counsel and was ultimately destroyed by Lü Guang. This was the consequence of neglecting contested ground.

Multiple military strategists agreed on this principle: Chen Hao stated that whoever first occupies strategic terrain can defeat greater numbers with fewer troops; Du You emphasized the advantage of natural barriers like mountain passes; Mei Yaochen and Wang Xi argued that the first to arrive gains the upper hand; He Shi, citing Sunzi’s tactics, advised that if the enemy seizes key terrain first, one should avoid direct assault—instead, feign retreat to mislead them, then ambush their reinforcements. Conversely, if we hold the position and the enemy employs this tactic, we must deploy elite troops to defend while setting up flanking ambushes.

Zhang Yu concluded that Tang Taizong’s victory—holding the strategic pass at Chenggao with just 3,000 men to trap Dou Jiande’s 100,000-strong army—exemplified overcoming strength with weakness. These historical cases all prove that strategically vital terrain is indeed the decisive factor in victory or defeat.

In the commentaries on The Art of War, several military strategists provided detailed explanations of two strategic terrains: "intersecting ground" (交地) and "pivot ground" (衢地).

Regarding "intersecting ground" (areas with crisscrossing roads accessible to both sides):

Cao Cao described it as terrain where main roads intersect. Du Mu added that such flat, open areas are suitable for both sides to engage in confrontation. Chen Hao emphasized that these interconnected pathways require special defensive attention, with troops maintaining continuous vigilance from front to rear. Du You noted these regions contain multiple access routes that are difficult to completely blockade. Master He recounted how the King of Wu once consulted Sun Tzu about such terrain: to prevent enemy incursion, one must strengthen border defenses and block key passages; when forces are evenly matched, troops can be divided for ambush while feigning laxity to launch surprise attacks. Zhang Yu concluded that these areas contain numerous interconnected routes that defy complete isolation.

Concerning "pivot ground" (strategic territory bordering multiple states):

Cao Cao identified this as confronting an enemy while other states flank the area. Meng Shi gave the example of Zheng State sandwiched between Qi, Chu, and Jin. Li Quan advised securing alliances with neighboring states first to gain their support. Du Mu argued one must initially control these strategic strongholds bordering three states while uniting surrounding powers. Both Mei Yaochen and Wang Xi stressed that whoever reaches such territory first gains the support of neighboring lords.

The grand strategy of ruling the world lies in forming extensive alliances, for then all under heaven will follow you. Commentator He explains that "qudi" (strategic crossroads) refers to transportation hubs that military strategists must contend for, controlling multiple thoroughfares. Whoever first occupies such locations will inevitably gain popular support—holding them brings security, while losing them invites peril.

King Wu once asked Sun Tzu: "If we must contend for a strategic crossroads but the journey is distant, and even with urgent dispatch we cannot arrive in time, what should we do?" Sun Tzu replied: "In regions where feudal lords' territories intersect like a spider's web, when our army faces the enemy, the key lies in first establishing friendly relations with neighboring states. The concrete method is: prepare generous gifts, dispatch envoys, and form alliances with adjacent countries. Thus even if our troops arrive somewhat late, we shall gain support from various states. When our side obtains multi-faceted assistance while the enemy becomes isolated, with nations forming pincer attacks from multiple directions, the foe will panic in disarray."

Commentator Zhang Yu elaborates: "Strategic crossroads connect in all directions—our army need only confront the enemy to our front while maintaining connections with neighbors on three sides. We should establish alliances with these countries beforehand as reinforcements. What we call 'arriving first' means sending envoys bearing lavish gifts to conclude treaties. Thus even if our main forces arrive later, we've already secured foreign support."

Territory deep in enemy domain with multiple cities at one's rear is called "zhongdi" (critical terrain of no return). Cao Cao's commentary identifies this as terrain from which retreat proves difficult. Li Quan cites historical examples: when Bai Qi attacked Chu and Yue Yi invaded Qi, both faced such circumstances. Du Mu explains: "Advancing too deeply into enemy territory, passing too many cities, with all river crossings and bridges controlled by the enemy, key routes entirely occupied—retreat becomes impossible." Du You further clarifies: "The term 'zhong' (critical) denotes difficulty of return, while 'bei' (rear) indicates great distance (interchangeable with the character for 'multiple'), meaning far from one's own cities—when penetrating enemy lands, one must commit wholly to battle."

Mei Yaochen observes: "Exploiting weaknesses to advance ever deeper, passing increasing numbers of cities, with all crossings and passes severed—this constitutes 'terrain of critical difficulty.'" Wang Xi maintains: "When an army reaches such terrain, the situation becomes extremely grave." He's commentary notes: "When fighting in critical terrain, being deep in enemy territory makes resupply from home impossible—if we don't seize enemy provisions, what will our troops eat?"

King Wu further questioned Sun Tzu: "Our army penetrates critical terrain, traversing numerous hazards with supply lines cut off. Retreat proves impassable, yet foraging in enemy territory risks soldierly laxity—what then?" Sun Tzu answered: "In critical terrain, when troops travel light and fight fiercely but supplies are severed, they must plunder provisions to survive. Provided we can obtain food locally..."

This passage primarily discusses several types of special terrain in ancient military tactics and corresponding strategies for dealing with them.

Regarding "collapsed land" (referring to terrain damaged by water and difficult to traverse): These areas have loose, unstable soil unsuitable for constructing defensive works, and armies should pass through them quickly. As King Wu asked Sun Wu, prolonged marches through such rugged mountains and rivers would exhaust soldiers. If enemies attack from both front and rear with ambushes on the flanks, while chariots and cavalry block key passages, the situation becomes perilous. Sun Wu advised first sending light chariots to scout, then dividing forces to advance along both sides according to the terrain. The commander should oversee the overall situation to identify breakthrough points, allowing troops to rest when exhausted.

Concerning "encircled land" (terrain with narrow entrances and winding retreat routes): These areas are difficult to enter or exit, making them prone to enemy ambushes. Due to logistical challenges, even small enemy forces can besiege larger armies. Surrounded by mountains with narrow approaches and convoluted escape routes, numerical superiority becomes ineffective—only extraordinary tactics can achieve a breakout.

Military strategists unanimously emphasize: When advancing deep into enemy territory past multiple hostile cities, soldiers tend to focus solely on combat without thoughts of retreat. Such "hard-to-withdraw terrain" resembles Sima Jingwang's assessment of Zhuge Ke: "Fully armored and penetrating enemy lands, their momentum becomes unstoppable." However, when encountering water-damaged terrain or encircled positions, armies must either pass through swiftly or achieve victory through unexpected maneuvers.

King Wu asked Sun Wu: "Our army is trapped in perilous terrain—facing strong enemies ahead while backed against treacherous ground behind. The foe has cut our supply routes and occupies advantageous positions. They beat drums and shout but do not attack, clearly observing our response. How should we handle this situation?"

Sun Wu replied: "When encircled in dangerous territory, seal all escape routes to demonstrate unwavering resolve. Make every soldier regard the camp as his home, uniting the entire army as one. For several days, refrain from cooking meals to feign disarray and weakness. When the enemy perceives our apparent laxity, they will grow overconfident. Then rouse your troops' morale, station elite forces in ambush on both flanks of the narrow pass, and launch a sudden drum-assisted assault. If the enemy resists fiercely, attack from front and rear simultaneously while flanking from both sides, forming pincer movements."

Sun Wu continued: "If the enemy sets ambushes within our encirclement, luring us with bait and confusing us with banners to create chaotic disorientation, what then?" He advised: "Dispatch thousand-man units bearing banners to block strategic passes, probe with light troops in feigned attacks, deploy formations without direct engagement, and maintain position after contact—these methods unravel enemy schemes."

Commentator Zhang Yu added: "In terrain where one defender can hold against a thousand—with danger before and behind—victory lies in concealed surprise attacks."

Regarding "death ground" (utterly hopeless positions): Cao Cao described it as being trapped between impassable mountains ahead and unfordable waters behind. Li Quan noted such terrain demands immediate battle—delay spells doom. Du Mu cited Tang general Li Jing's view: "Armies without guides may enter valleys flanked by cliffs where horses cannot maneuver, trapped between dead ends. Before formations stabilize, powerful enemies strike—no advance foothold, no retreat path. Unable to fight or defend securely, halting wastes opportunity while moving invites encirclement. Without water or provisions, men and horses exhaust mentally and physically." Such impregnable positions, if seized by enemies first, render even elite troops powerless. On death ground, only swift decisive battle brings survival—demanding total commitment to turn defeat into victory.

When an army finds itself in a desperate situation, it may paradoxically turn danger into safety. Chen Hao, a Tang dynasty military strategist, used this analogy: A man in a death-ground position is like sitting in a leaking boat or taking shelter in a burning house. Jia Lin, another military theorist, elaborated: If troops are trapped between high mountains and deep valleys where enemies can easily attack from outside while escape becomes nearly impossible, the only chance for survival lies in immediate, desperate combat. Delaying until morale collapses and provisions run out inevitably leads to destruction.

Mei Yaochen, a Song dynasty military expert, added: When advancement is blocked, retreat cut off, and all paths seem closed, swift and decisive battle is the sole option. Scholar He's commentary notes: Fighting fiercely in a death-ground may bring survival, while passive defense guarantees certain death.

King Helü of Wu once asked Sun Tzu (author of The Art of War): "If my army penetrates deep into enemy territory and becomes surrounded, with all escape routes sealed, how can I motivate soldiers to fight desperately for a breakthrough?" Sun Tzu replied: First, dig deep trenches and build high ramparts, feigning preparations for a prolonged siege while secretly conserving strength. Then slaughter oxen and burn supply wagons to reward the troops, destroy remaining provisions, fill in wells and dismantle stoves, cut off hair and discard helmets—all to demonstrate the severing of retreat. Once soldiers resolve to fight to the death, sharpen weapons, concentrate forces for a fierce assault on both flanks, and unleash thunderous drumbeats and war cries to intimidate the enemy. Simultaneously, dispatch elite units to strike the enemy's rear swiftly—this is the method for surviving hopeless circumstances. Hence, failing to strategize when trapped leads to desperation, and failing to fight desperately when cornered brings annihilation.

The King then asked: "What if it's my army surrounding the enemy?" Sun Tzu responded: "When enemies are trapped in perilous mountain passes or gorges with no escape, deploy ambushes while deliberately leaving an apparent route open. Seeing an exit, their fighting spirit will crumble—then strike, and even the largest force can be crushed." Military doctrine further states: When enemy morale runs high in a death-ground, avoid direct confrontation. Instead, covertly control strategic points, use light troops to bait them, but refrain from engagement—this is the tactic to break their desperate resolve.

Zhang Yu, a Song dynasty strategist, concluded: When an army is stranded in treacherous terrain with no provisions inside and formidable enemies outside, commanders must immediately rally troops for decisive battle without hesitation. Thus, in "dispersive ground" (where soldiers fighting near home may easily desert), avoid rash combat. Li Quan of the Tang dynasty explained this prevents troop disintegration, a view echoed by Du Mu, another Tang military scholar.

(Note: All specialized terms like "death-ground" (死地) and "dispersive ground" (散地) follow The Art of War conventions without parenthetical pinyin, as they're established translations in military classics context.)

Jia Lin states that when fighting in open terrain with no natural defenses (scattered ground), soldiers are prone to disintegration and desertion. Armies stationed in such areas should avoid frequent engagements. While various schools of thought have their own theories on terrain, if the commander enforces strict discipline and the soldiers are both obedient and devoted—even unafraid of death—how could they possibly scatter?

Mei Yaochen adds: When our army fights on home soil, soldiers are attached to their homeland and preoccupied with survival, making it difficult to maintain stable formations or secure victory in battle. Therefore, active engagement should be avoided.

Wang Xi points out: Decisive battles in this type of terrain will cause soldiers to panic and flee. Zhang Yu further explains: Soldiers cling to life and fear death, so combat should not be initiated lightly. King Wu once asked Sun Tzu: "If scattered ground is unsuitable for battle, should we simply hold our position and not engage? What if the enemy attacks our smaller cities, plunders our fields, blocks our access to firewood, and cuts off critical routes—then waits for us to weaken before launching a sudden assault? How should we respond?" Sun Tzu replied: "When the enemy penetrates deep into our territory, they are single-mindedly seeking battle. Meanwhile, our troops, attached to their homeland, lack firm resolve. In such cases, we must gather manpower, stockpile provisions, fortify cities and strategic points, and dispatch light units to sever the enemy’s supply lines. Deny them the chance to fight, cut off their provisions, and prevent them from seizing resources in the wilds. Only when they are exhausted and starving should we lure them into battle to secure victory. If engaging in open combat, we must rely on favorable terrain to set ambushes; where no natural defenses exist, we should use weather conditions for concealment and strike unexpectedly when the enemy is unprepared."

Regarding "light ground" (the fringes of enemy territory, just after crossing the border), Li Quan emphasizes the need to prevent desertion. Du Mu explains: "Light ground," as described in military strategy, refers to when an army has just entered enemy territory but has yet to secure strategic positions. Soldiers, longing for home, are prone to retreat. At this stage, elite cavalry should be deployed in ambush—if the enemy attacks suddenly, counter decisively; otherwise, advance swiftly.

Du You stresses: When morale is unstable, combat must be avoided. Mei Yaochen advises: "Upon entering enemy territory before securing strategic points, soldiers are unsettled. Avoid approaching major cities or main roads; instead, advance quickly." Wang Xi states: "Unless exceptional circumstances arise, do not linger." Zhang Yu concludes: "Soldiers are likely to flee homeward, so prolonged stays are inadvisable." King Wu asked: "When soldiers yearn for home, reluctant to advance and quick to retreat, and their morale wavers before securing key positions—what then?" Sun Tzu replied: "In light ground, soldiers are not yet fully committed. Create deceptive appearances, feign retreat, and dispatch elite cavalry to launch covert surprise attacks on the enemy."

In Commentaries on Sunzi's Art of War, several essential analyses on military strategy are presented:

Regarding tactics for "contested terrain" (strategically vital ground that military commanders must fight for), if the enemy has already secured advantageous positions, one should avoid direct assault. Cao Cao advises seizing favorable positions first. Both Li Quan and Du Mu emphasize that when the enemy holds the terrain advantage, the wise course is to abandon forceful attacks. The King of Wu inquired: "If the enemy occupies key terrain first, trains elite troops, and defends rigorously, what should we do?" Sunzi replied: "The principle for contested terrain is this—yielding may bring gain, while insistence may lead to loss. If the enemy holds the position, do not attack head-on. Feign retreat while creating diversions to split their forces. Conceal elite troops in ambush; when the enemy mobilizes reinforcements, we can turn the tables." If our forces arrive first and the enemy employs this tactic, we must station elite troops to hold the position, pursue with light units, and set ambushes at strategic points. When the enemy turns back, spring the trap—this is the path to complete victory.

Concerning "intersecting terrain" (crossroads and communication hubs), Cao Cao and Li Quan stress maintaining troop cohesion. Du Mu particularly notes that in open plains, forces must stay connected to prevent enemy disruption. Jia Lin suggests forming alliances but never severing contact, while Du You and Mei Yaochen advocate maintaining continuous marching routes. Wang Xi highlights securing supply lines, and Zhang Yu proposes using surprise ambushes for victory. The King of Wu asked: "How to block enemy passage through intersecting terrain?" Sunzi advised: "Beyond strengthening border defenses, completely seal the routes and fortify strategic points. Without these preparations, the enemy will exploit vulnerabilities."

These commentaries, through multiple military strategists' perspectives, systematically elaborate on the principles of warfare across different terrains. The core philosophy consistently emphasizes adapting to local conditions and responding with flexibility.

When the enemy is well-prepared and capable of attacking us while we cannot launch an offensive against them, what should be done? And how should we respond when both sides have equivalent military strength?

Sun Wu replied: Since we cannot take the initiative to attack while the enemy can invade, we should disperse our forces for concealed defense, deliberately feigning laxity and incompetence. When the enemy advances, set ambushes and strike them unexpectedly.

In strategic thoroughfares (衢地, key communication routes), prioritize diplomatic alliances. Cao Cao emphasized forming alliances with neighboring states; Li Quan stressed befriending allies; Du Mu explained this as securing relations with adjacent countries; Meng Shi highlighted that gaining allies ensures security while losing them invites danger; Mei Yaochen noted that in interconnected regions, lavish gifts should be used to forge ties; Wang Xi argued that in such terrain, external support is essential; Zhang Yu summarized the need to first ally with neighbors.

King Wu asked: In strategic thoroughfares, preemptive action is crucial—but if our forces are distant and set out late, even swift horses cannot compensate for the delay. What then? Sun Wu answered: In regions where feudal powers intersect (四通之地), send envoys lightly equipped with generous gifts to establish alliances and friendly relations. Even if troops arrive later, they will gain widespread support. Meanwhile, streamline forces, occupy advantageous terrain, and create a pincer movement with allied nations, making the enemy unable to withstand the pressure.

In "heavy terrain" (重地, deep enemy territory), sustain the army by seizing local supplies. Cao Cao advised stockpiling provisions; Li Quan warned that deep incursions must not violate moral principles and lose popular support, citing Liu Bang’s restraint in Xianyang—neither harassing women nor plundering wealth; Du Mu suggested transporting provisions for prolonged warfare when进退两难 (进退两难, caught between advance and retreat); Meng Shi advocated "living off the enemy" (因粮于敌); Mei Yaochen noted that during distant campaigns, seize enemy stockpiles to maintain supplies; Wang Xi stressed plundering prosperous regions to replenish reserves, as shortages spell peril; Zhang Yu emphasized motivating troops to seize provisions to prevent scarcity.

King Wu asked: In heavy terrain, we often bypass cities, risking severed supply lines. If we wish to retreat...

In the Annotations on Sunzi's Art of War, several military strategists provided incisive analyses of tactical approaches under different terrain conditions:

Regarding the "critical terrain" (areas deep in enemy territory with difficult supply lines): When an army operates in regions with logistical challenges, it may seize enemy provisions to sustain itself. Captured grain and cloth should be handed over to superiors, with rewards given for substantial hauls. For withdrawal, troops should dig deep trenches and build high ramparts to confuse the enemy while secretly clearing obstacles along escape routes. Light chariots should then advance covertly, raising dust as cover, using cattle and horses as decoys. If the enemy pursues, respond with drum signals—ambush troops should attack from both flanks at the appointed time to achieve victory.

Concerning "difficult terrain" (ruined or impassable land), all commentators agree on rapid transit: Cao Cao advises against lingering; Li Quan notes defensive works are inadvisable; Mei Yaochen emphasizes ruined ground cannot be held; Zhang Yu concludes such terrain demands swift passage. Addressing King Helü's dilemma about mountain warfare (ambushes ahead and pursuers behind), Sunzi recommends first dispatching scout chariots to probe, then dividing and converging main forces to breach weak points, with intermittent rest during the advance.

For "encircled terrain" (positions with no retreat), strategists unanimously advocate ingenious breakout tactics: Cao Cao prescribes extraordinary stratagems; Li Quan states the wise avoid encirclement; Du Mu stresses perilous cunning; Du You highlights deceptive maneuvers; Mei Yaochen analyzes overcoming simultaneous frontal/rear attacks through strategy; Zhang Yu summarizes using intellect when force fails. When the king asks about facing strong enemies ahead with severed retreat, Sunzi advises sealing escape routes to demonstrate resolve, uniting the army as one family, withholding cooked meals for days while feigning disarray. Once the enemy lowers guard, motivate troops for a ferocious assault.

(Note: "Light chariots" refer to fast, unarmored war chariots; "gagging" describes the ancient stealth tactic of soldiers biting horizontal wooden sticks to prevent noise during movement.)

This passage explains the tactical principles of "fighting in desperate positions" and "disrupting enemy forces" in ancient military strategy.

When an army is trapped in a situation with no retreat, it must fight with desperate determination. Military strategists like Cao Cao and Li Quan believed that in such a "death ground," soldiers would naturally fight with extraordinary courage—this is what the Art of War refers to as "placing them in a position of certain death, and they will survive." Specific methods include: digging deep trenches and building high fortifications to maintain a defensive posture; slaughtering cattle and horses, burning chariots to reward the troops; destroying food supplies and filling in wells; even cutting off hair and discarding caps to demonstrate absolute resolve. Then, concentrate forces to fiercely attack the enemy’s flanks, beating drums and shouting to create an overwhelming momentum, throwing the enemy into panic and confusion.

A truly skilled commander can disrupt the enemy’s overall deployment. Commentators like Mei Yaochen pointed out that superior tactics should achieve the following: preventing the enemy’s front and rear forces from coordinating, preventing larger and smaller units from supporting each other, severing communication between officers and soldiers, and cutting off the chain of command. Specific methods include deploying decoys to mislead the enemy, feigning attacks east while striking west, shifting unpredictably between front and rear, and creating false impressions. This forces the enemy to scatter their forces in defense, plunging them into chaos and preventing them from regrouping, ultimately paralyzing their command structure.

Du Mu further explains that deception should be used extensively to confuse the enemy, making it impossible for them to discern one’s true intentions. By maintaining concealment while forcing the enemy to disperse their defenses, their morale will collapse, their command will falter, and they will be unable to mount an effective resistance. This is the essence of Sun Tzu’s principle: "A skilled commander can make the enemy’s front and rear forces lose contact with each other."

This compilation gathers commentaries from multiple ancient military strategists on The Art of War, focusing on how to respond to different states of enemy forces:

When the enemy is scattered and unable to regroup, or when they are barely assembled but lack cohesion, Wang Xi points out that the key lies in flexibly employing orthodox and unorthodox tactics (zheng and qi), coordinating them like the seamless movement of hands and feet. Zhang Yu adds that in such cases, one should strike unexpectedly at weak points, leaving the enemy unable to connect their front and rear, plunging them into chaos and preventing effective defense.

Regarding whether to engage in military action, Cao Cao emphasizes the need to create disorder, stripping the enemy of their organizational capacity. Both Li Quan and Mei Yaochen argue that one must weigh the advantages and disadvantages—fight if there is benefit, hold back if there is none. Zhang Yu further clarifies that even if the enemy is already in disarray, one must still assess the strategic benefits of the situation.

A question arises: What if the enemy is numerous and maintains strict discipline? Cao Cao explains that this is a rhetorical question meant to prompt self-reflection. Mei Yaochen highlights the essence of the issue: What strategy should be employed when facing a strong and well-organized enemy? Zhang Yu notes that previous discussions dealt with evenly matched scenarios, whereas now the challenge is to address the tactics when the enemy is stronger.

The solution to this lies in "first seizing what they cherish." Cao Cao interprets this as depriving the enemy of their relied-upon advantages, such as occupying strategic locations first. Li Quan considers this one of Sun Tzu’s secret principles—the "cherished" refers to what the enemy values most, whether material wealth or loved ones; controlling these can manipulate the enemy’s actions. Du Mu elaborates that one should seize favorable terrain, cut off supply routes, and control the three vital lifelines on which the enemy depends. Chen Hao and Mei Yaochen summarize that anything the enemy prioritizes can serve as a point of control—taking these first grants the initiative, forcing the enemy into passivity.

This passage elucidates the essential principles of military strategy: swiftness is paramount, striking when the enemy is unprepared. Wang Xi explains that by first seizing advantageous terrain and using unconventional tactics to cut off enemy supply routes, we can force the adversary to act according to our plans. Zhang Yu further notes that since enemies value strategic positions and provisions most highly, capturing these first compels them to submit to our arrangements.

The crux of military operations lies in speed—exploiting the enemy's delayed reactions, taking unexpected routes, and attacking undefended positions. Cao Cao identifies this as Sun Tzu's core teaching on warfare. Li Quan emphasizes that victory depends on striking where unexpected and attacking where unprepared. Du Mu synthesizes this as the essence of strategy: identifying enemy vulnerabilities, advancing through unanticipated paths, and assaulting unguarded positions—a commander's most vital skill.

Chen Hao elaborates that upon detecting enemy negligence, immediate action without hesitation is imperative. Mei Yaochen stresses the fleeting nature of opportunities—one must act while the enemy remains unaware. Wang Xi observes that while military operations generally require speed, this is especially true when seizing what the enemy values most.

He Shi cites the historical example of Meng Da during the Three Kingdoms period: After surrendering to Wei and being appointed governor of Xincheng, Meng secretly conspired with Wu and Shu. When Sima Yi (Xuanwang) discovered this, he feigned reassurance through letters while rapidly marching his troops to the city in just eight days. Though his generals advised cautious observation, Sima Yi recognized Meng's vacillating nature and struck during his moment of indecision. By the time Wu-Shu reinforcements arrived, Sima Yi had already completed his deployments. This case vividly illustrates the principle that "speed is the essence of warfare"—Meng Da had assumed Sima Yi needed a month to mobilize, leaving him utterly unprepared when besieged within eight days, resulting in decisive defeat.

This passage explains the military principle that "speed is crucial in warfare." Several famous historical battles demonstrate how seizing opportunities for swift action often leads to victory.

For instance, when Sima Yi attacked Shangyong City, Meng Da (a Shu Han general during the Three Kingdoms period) believed the city was secure with water on three sides, relying only on wooden palisades for defense. Sima Yi, however, crossed the waters directly, breached the barriers, advanced through eight routes simultaneously, and forced Meng Da's subordinates to surrender the city within sixteen days. Similarly, when Li Jing (a renowned Tang dynasty general) campaigned against Xiao Xian, the latter assumed the autumn floods and treacherous Three Gorges terrain would prevent Li Jing's advance, thus lowering his guard. Li Jing seized the moment when water levels suddenly dropped to appear at the city gates, achieving decisive victory.

The military strategist Duke Weiguo (Li Jing) summarized: The essence of warfare lies in divine speed (shensu). This requires selecting elite troops, enforcing strict commands, ensuring soldiers recognize banner signals and drum communications, maintaining robust logistics, building fortifications, surveying terrain, appointing capable personnel, and training troops in both conventional and surprise tactics. Prepared thus, even an enemy striking like lightning can be countered with composure.

However, caution is needed: When facing enemies with resourceful commanders, cohesive troops, strict discipline, superior equipment, and high morale, reckless haste must be avoided. Instead, conserve strength, build energy, evade the enemy's momentum, and adopt protracted warfare—as exemplified by Lian Po's defensive stand against Bai Qi during the Warring States period, or Sima Yi's deliberate inaction against Zhuge Liang.

Finally, Zhang Yu (a Song dynasty military theorist) added: The core of divine speed in warfare lies in striking when the enemy is unprepared. Like the saying "a sudden thunderclap leaves no time to cover ears," this represents the supreme strategy of military doctrine.

This passage discusses strategies for operating deep within enemy territory. When an army penetrates far into hostile lands, soldiers become resolute knowing there’s no retreat, making them nearly unstoppable to defenders. As Guangwujun of Zhao advised Han Xin: "An expeditionary force fighting far from home carries an unstoppable momentum."

Procure provisions from the enemy’s fertile countryside to ensure full logistical support. Meticulously rest and preserve troops—avoid exhausting them, accumulate morale, conserve strength, while secretly maneuvering forces and devising strategies to keep the enemy guessing. As Cao Cao noted: "Nourish Jing (essence) and store Qi (vital energy), deploy troops unpredictably to baffle adversaries."

Practical methods include: camping near water sources and pastures to secure supplies; acting prudently while carefully tending to soldiers’ needs. Historically, when Wang Jian campaigned against Chu, he ignored provocations and focused on comforting his troops. Observing soldiers training with stone-throwing games, he recognized their pent-up combat readiness—ultimately crushing Chu in one decisive strike.

Mei Yaochen summarized: "Seize enemy resources to sustain your army, let soldiers recuperate fully, concentrate elite forces, and craft unpredictable stratagems." Wang Xi added: "'Meticulous nourishment' means tending to troops’ daily needs with thorough care—maintaining their edge while concealing true intentions until the moment to strike arrives."

When troops are positioned at strategically vital locations, provisions should be obtained from fertile regions to ensure supply, while constructing solid defensive fortifications. Soldiers should be regularly reassured and not overworked, maintaining high morale and abundant physical strength. Tactics should be devised to make them unpredictable to the enemy, striking swiftly to seize victory the moment an enemy weakness is detected. Historically, General Wang Jian employed this strategy when attacking the state of Chu.

Placing troops in a situation with no retreat compels them to fight desperately rather than flee. Military strategists observe that when soldiers have no escape routes in any direction, they will fight with all their might, preferring death over retreat. Knowing they must fight to the end, they abandon thoughts of withdrawal.

In a life-or-death scenario, soldiers inevitably give their all. Strategists like Cao Cao noted that when people face certain doom, how could they not fight desperately for survival? As the Wei Liaozi states: A single swordsman, cornered in the marketplace, will make ten thousand men avoid him—not because he is exceptionally brave, but because the mindset of one who must die differs entirely from that of one who clings to life.

When all soldiers are thrust into peril together, fear dissipates. Du Mu and others explain that shared danger unites the entire army in solidarity, banishing terror. Wang Xi adds that once trapped in adversity, resolve only strengthens. Zhang Yu asserts that with death as the only option, fear of the enemy vanishes.

An army with no retreat becomes unshakable in spirit; deep in hostile territory, soldiers bond tightly. Cao Cao interprets "拘" (ju) as unity, Li Quan defines "固" (gu) as steadfastness, and Du Mu concurs.

When troops penetrate deep into enemy territory with no path for retreat, the soldiers will unite as if bound together by ropes. Mei Yaochen explains that when people find themselves with no avenue of escape, their hearts naturally become resolute; when thrust into perilous circumstances, their willpower naturally focuses. Zhang Yu adds that when soldiers are surrounded by overwhelming forces with nowhere to turn, this sense of being constrained paradoxically stabilizes their morale.

Cornered men will inevitably fight with desperate courage. Cao Cao observes that humans struggle with their last ounce of strength when all escape routes are cut off. Li Quan encapsulates this state with the phrase "resolved to die." Du Mu elaborates that "having no alternative" refers to an entire army being trapped in a fatal position, where survival depends on fighting to the death. Mei Yaochen and He Shi concur with Du Mu's interpretation, while Zhang Yu states this represents circumstances compelling total combat commitment.

Such an army requires no deliberate drilling yet remains vigilant, needs no coercion to achieve objectives, demands no discipline to maintain unity, and follows orders without explicit commands. Cao Cao describes this as obtaining results without conscious pursuit. Li Quan believes placing soldiers in mortal danger makes them maximally effective without orders. Du Mu notes that in desperate straits, the entire force unites spontaneously—needing no training to stay alert, no persuasion to share purpose, no enforcement to maintain trust.

Meng Shi calls this the principle of winning without deliberate striving. Mei Yaochen clarifies: armies stay vigilant without drilling, achieve goals without coercion, bond without discipline, and obey without commands—all because shared peril unites the three divisions. Wang Zhe views this as human nature's response to danger. Zhang Yu concludes that in crisis, people naturally unite like passengers on the same boat, where even those of different ethnicities cooperate.

Prohibit superstitious talk and eliminate doubts, so soldiers remain steadfast unto death. Cao Cao advises banning ominous rumors and dispelling unsettling strategies. Li Quan states that forbidding superstitious discourse and morale-shaking matters prevents disaster. Du Mu cites Huang Shigong: "Forbid shamans from predicting battle fortunes for officers..."

To make soldiers resolute in their determination, their doubts must be dispelled so they will pledge their loyalty unto death without second thoughts. Mei Yaochen explains that as long as superstitious and strange beliefs are not spread, nor unsettling rumors circulated, the army will not fall into disorder, and the soldiers will fight to their last breath.

Wang Xi points out that ominous portents and supernatural phenomena easily confuse people's minds and thus must be strictly forbidden. Zhang Yu adds that to make soldiers fight desperately, officers must be prohibited from discussing auspicious or inauspicious signs to avoid unsettling morale. Only by eliminating soldiers' doubts will they focus wholeheartedly on facing death. The Methods of Sima mentions "eliminating superstition," which aligns with this principle. However, some generals have acted contrary to this—for instance, when Tian Dan defended Jimo, he deliberately had a soldier impersonate a deity, attributing every command to divine will, ultimately crushing the Yan army.

The army demands that soldiers carry no excess possessions, not because wealth is despised, nor does it require them to disregard life out of hatred for longevity. Cao Cao explains that burning possessions does not stem from disgust at having too much wealth, and sacrificing life is a last resort. Du Mu argues that if soldiers carry valuables, they will cling to life and fear death. Mei Yaochen states that this is a forced measure—expending all resources and fighting to the death out of necessity. Wang Xi notes that supplies need only be sufficient, for if soldiers covet wealth, they will seek to preserve themselves. Zhang Yu concludes that wealth and longevity are naturally cherished by people; the reason for burning treasures and sacrificing lives is not hatred for these things but the demands of circumstance.

When military orders are issued, seated soldiers weep until their robes are soaked, and those lying down shed tears that stream down their faces. Cao Cao says this is because all are resolved to die. Li Quan interprets this as the tragic resolve when abandoning possessions and life. Du Mu records that before battle, a motivational speech would declare: "Today's battle hinges on this single effort. If we do not fight desperately, our bones will lie exposed in the wilderness, torn apart by beasts." Mei Yaochen sees this as an effective method to inspire the will to fight to the death. Wang Xi attributes it to the power of emotional inspiration. Zhang Yu summarizes that this solemn motivation makes soldiers weep uncontrollably—the purpose of pre-battle orders is to make them understand: this battle is a matter of life and death.

Someone asked: Normally when marching troops, we reward soldiers by letting them drink wine, perform sword dances, wrestle in pairs, and shout to drumbeats—all to boost their morale. If we make soldiers weep, wouldn’t that dampen their fighting spirit?

The answer is this: First, you must solidify the soldiers’ resolve to fight to the death, then sharpen their aggressive energy (Qi). With this, no battle is unwinnable. Without the determination to die, even the fiercest morale cannot secure victory. Consider Jing Ke’s farewell at the Yi River: the warriors wept at first, but when they heard the stirring notes of the yusheng melody, their hair stood on end in rage—this is the kind of courage that arises when soldiers are cornered with no way out, like the bravery of Zhuan Zhu or Cao Gui. (Zhuan Zhu was the assassin who killed King Liao of Wu during the Spring and Autumn period; Cao Gui was a Lu state warrior who once forced Duke Huan of Qi to submit at swordpoint.)

A master of warfare acts like the shuairan snake of Mount Chang. Strike its head, and the tail responds; strike its tail, and the head counters; strike its middle, and both ends attack at once. (Zhang Yu’s commentary: This analogy illustrates battlefield formations—like the ancient Eight Formation Diagram, where any assault on one part is met with coordinated resistance from the rest.)

Someone asked: Can an army truly function like the shuairan snake? The answer is yes. The people of Wu and Yue were bitter enemies, yet when caught in a storm on the same boat, they helped each other like left and right hands. (Mei Yaochen notes this was compelled by circumstance, while Zhang Yu adds: If even sworn foes cooperate in crisis, how much more should a disciplined army move with the unity of the shuairan snake?)

This scripture passage discusses why relying solely on fixed formations and rigid defensive positions is unreliable in military strategy.

Cao Cao explains that while tethering horses and burying chariot wheels (ancient methods for maintaining fixed formations) may demonstrate resolute determination to hold ground, such approaches are too inflexible compared to adaptable responses. Even with secured horses, these methods cannot be fully depended upon.

Li Quan argues that when troops are placed in situations with no retreat, they will naturally cooperate like a snake's head and tail working together. Just as people from Wu and Yue (historically rival states during the Spring and Autumn period) would rescue each other when caught in a storm aboard the same boat. Relying solely on fixed formations proves insufficient.

Du Mu elaborates further: while arranging horses in square formations and burying chariot wheels may show determination to hold position, this still isn't solid or reliable enough. The key lies in flexible adaptation—placing soldiers in situations where they must fight desperately, compelling them to automatically assist each other like coordinated left and right hands. This constitutes the path to certain victory.

Chen Hao uses the Wu-Yue boat analogy: even historical enemies like Wu and Yue would rescue each other in emergencies when circumstances demanded. The art of warfare involves placing troops in situations where they must fight to the death, ensuring frontline and rear units naturally support each other. If sworn enemies can cooperate, how much more should allied forces? The crucial factor lies in creating circumstances that compel such cooperation.

Both Wang Xi and Zhang Yu emphasize that rather than depending on fixed formations, soldiers should coordinate as seamlessly as left and right hands. While placing troops in perilous situations forms the foundation, true victory requires employing wisdom to unite the army as one—this is the essential key to success.

Regarding the concept of "uniform courage being a matter of governance," Li Quan, Du Mu and Chen Hao all point out that achieving consistent bravery and unified action throughout an army fundamentally depends on strict military discipline. Rigorous command ensures the brave don't advance recklessly while the timid don't retreat, enabling perfect coordination across all forces.

This passage elucidates the essence of ancient military command, focusing on how to lead troops with the effortless control of one's own limbs. Multiple military strategists (Mei Yaochen, Wang Xi, Zhang Yu, etc.) interpreted the same principle from different perspectives:

A true commander can unite the entire army to move as one body. The key lies in making soldiers understand they must support each other when facing danger - this naturally fosters shared hatred against the enemy. Cao Cao and Li Quan particularly emphasized that such unity resembles forces of varying strength finding their proper positions according to terrain - even weaker troops can overcome adversaries when occupying advantageous ground, while stronger forces become doubly formidable.

Du Mu employed vivid imagery: commanding massive armies should feel as effortless as guiding a single person's hand. Jia Lin further explained that this art of command enables millions of troops to maneuver flexibly, shifting formations front and rear, left and right, with the coordination of a single body's limbs. Mei Yaochen noted this "limb-like responsiveness" stems from "inevitable momentum" - when deployment is rational, soldiers naturally follow commands.

The passage concludes with the commander's cultivation: one must maintain a profoundly serene mindset (stillness reaching profundity) and administer affairs with impartial rigor (uprightness bringing order). Cao Cao explained this means possessing a purified heart and far-reaching contemplation; Du Mu added that only commanders who are concise yet profound, unfathomable yet unbiased can truly govern armies effectively. This state requires both strategic wisdom in deployment and the commander's accumulated personal cultivation.

Yao Chen states: A general must be profoundly serene, making himself unfathomable to others; his conduct must be upright and self-disciplined, so that none can interfere with him. Wang Xi adds: Serenity prevents interference, profundity defies comprehension, uprightness avoids negligence, and self-discipline prevents disorder. Zhang Yu explains: In strategizing, remain tranquil and deeply concealed, making your plans unpredictable; in managing subordinates, enforce impartiality and strict discipline, leaving no room for laxity.

Regarding "keeping soldiers in ignorance by blocking their ears and eyes": Cao Cao interprets this as preventing premature involvement in planning—the people may share in the benefits but not in decision-making. Li Quan notes that strategies should not be disclosed to soldiers before they mature, while Mei Yaochen emphasizes that military tactics should be executed without requiring soldiers to understand their rationale. Zhang Yu concludes that soldiers should obey orders like the deaf and blind, following commands without question.

Concerning "altering actions and adjusting strategies to remain inscrutable": Li Quan asserts that changes must leave opponents unable to discern patterns. Du Mu stresses concealing the reasoning behind decisions. Mei Yaochen advocates modifying methods and plans, while Wang Xi cautions that implemented strategies must be renewed. Zhang Yu cites the example of Pei Xingjian: when he ordered the camp moved to higher ground, his officers were baffled, but after the original site was flooded that night, they asked how he had foreseen it—he simply replied, "Just follow my orders."

On "shifting encampments and taking circuitous routes to confound expectations": Li Quan observes that march routes must keep the enemy guessing. Du Mu explains this as deliberately choosing the longer path over the shorter, embracing danger over safety. These tactics embody the military principle of "deception knows no bounds," using information control and tactical variability to secure advantage.

This commentary on military strategy discusses the core tactics for commanders to control their troops' morale. Several military strategists interpret the wisdom of "placing soldiers in mortal peril to compel their survival" from different perspectives.

Chen Hao points out that commanders must meticulously arrange tactics without revealing their true intentions to the enemy. Jia Lin adds that securing strategic positions allows both flexible route adjustments and conceals troop movements from adversaries. Mei Yaochen and Wang Xi both emphasize confusing the enemy through changing encampments and circuitous marches, while Zhang Yu specifically advises avoiding treacherous terrain in favor of gentler routes—seemingly longer paths that actually conceal opportunities for surprise attacks.

The Hermit of Taibai (a recluse strategist) proposes a deeper insight: the art of warfare values deception, requiring commanders to deceive not only the enemy but sometimes their own troops—issuing orders without revealing true intentions. Like removing the ladder after ascending a height, Cao Cao and Li Quan explain this tactic unifies soldiers' determination, with Du Mu comparing it to a shepherd driving sheep, where soldiers need only follow advance and retreat commands.

Historical examples like Xiang Yu sinking boats after crossing the river or Meng Ming burning vessels embody this "cutting off retreat" tactic. Zhang Yu summarizes it as shepherding—where the commander controls the entire army like a flock, with soldiers knowing only to advance without possibility of retreat. He Shi further likens soldiers to docile sheep, wholly obedient to their commander-shepherd's direction.

This passage discusses how military commanders should direct their troops and strategies for combat in different terrains.

A general must concentrate his forces and commit them to perilous situations—this is the duty of command. Cao Cao explains that "peril" refers to difficult circumstances, while Mei Yaochen states that placing troops in danger yet achieving victory is what a commander must do. Zhang Yu adds that just like removing ladders or triggering mechanisms, putting soldiers in hazardous situations to secure triumph is precisely a general’s fundamental responsibility.

Regarding the variations of the nine types of terrain, the advantages and disadvantages of advancing or retreating, and the patterns of human nature, one must study them carefully. Cao Cao points out that human nature dictates advancing when there is gain and retreating when there is harm. Du Mu explains that the benefits and risks of advancing or retreating, as well as the constants of human behavior, all shift according to terrain. Mei Yaochen emphasizes the need to assess the advantages of movement brought about by changes in terrain. Wang Xi argues that one must know how to adapt to circumstances—retreat when conditions are unfavorable and advance when they are advantageous. Zhang Yu concludes that rigid adherence to rules is unwise; flexibility is key.

The principle for an attacking force (the "guest army"): When penetrating deep into enemy territory, morale stabilizes, but shallow incursions lead to disarray. Mei Yaochen clarifies that deep penetration fosters unity, while shallow entry causes dispersion. Zhang Yu explains that the side initiating the attack is the guest army—when it advances deep into hostile lands, cohesion strengthens, but shallow entry makes troops prone to scattering.

Operating beyond one’s own borders, crossing into enemy territory to fight, constitutes "desperate ground" (a position of extreme danger). Mei Yaochen states that neither advance nor retreat is favorable, leaving one in a dilemma. Wang Xi notes that this is an isolated deep thrust, requiring swift and decisive battle—such as when the King of Wu attacked Qi. Zhang Yu adds that leaving one’s homeland to wage war in another country is exceptionally perilous, citing the example of Qin troops passing through Zhou territory to launch a surprise attack on Zheng—a rare occurrence during the Warring States period.

A place where roads converge from all directions is called "intersecting ground" (a vital communication hub).

Mei Yaochen explains the phrase "when enemy forces occupy only one direction, allies will rally from all four sides" by noting that when the enemy holds a single position, neighboring states will naturally submit from all directions. Zhang Yu supplements this by stating that penetrating deep into enemy territory constitutes "strategically vital ground" (zhongdi).

Mei Yaochen observes that when fighting on strategically vital ground, soldiers regard the army as their home, thus maintaining unit cohesion. Conversely, operating in peripheral areas constitutes "light ground" (qingdi), where proximity to home makes it difficult for troops to remain focused.

Regarding the tactical situation where "having secure defenses behind and narrow passes ahead constitutes encircled terrain," Mei Yaochen clarifies this means having impassable barriers at the rear while facing constricted approaches. Zhang Yu adds that when frontlines are narrow and rear positions precarious, both advance and retreat become constrained.

Concerning the maxim "where there's nowhere to go, it's death ground," Mei Yaochen interprets this as being trapped with no escape routes. Zhang Yu specifies this means having no passage in any direction—front, rear, left, or right.

Therefore, different terrain requires distinct strategies:

On "dispersive ground" (sandi, where morale easily scatters), commanders must unify their troops' resolve. Li Quan advocates consolidating morale, while Du Mu observes that defensive operations require unity of purpose whereas offensives tend toward fragmentation. Mei Yaochen recommends fortifying strongholds and waiting for enemy laxity before striking. Zhang Yu supplements this by advising massing forces, stockpiling supplies, establishing ambushes in strategic positions, and attacking unpredictably.

On "light ground," maintaining tight unit cohesion is essential. Cao Cao and Li Quan both emphasize seamless troop coordination. Du Mu elaborates that in areas prone to dispersion, encampments should be closely connected—both to prevent desertion and facilitate mutual support. Du You stresses maintaining continuity during orderly withdrawals. Mei Yaochen advises continuous formations during movement and interconnected camps when stationary. Wang Zhe warns that broken connections leave soldiers without support. Zhang Yu underscores dense troop deployments and continuous lines to prevent accidents and desertion.

For "contested ground" (zhengdi, strategically crucial terrain), rapid occupation of rear positions proves critical. Cao Cao states that when advantageous terrain lies ahead, swift movement behind it becomes imperative. Li Quan recommends reinforcing troops for inevitable struggles. Du Mu argues that for truly vital ground, even belated efforts must be made to seize it. Chen Hao critiques both views, contending that if enemies already hold superior positions, contesting them leads to tactical disadvantage.

This passage discusses the ancient military strategist Sun Wu (Sun Tzu) and his commentators' strategies for dealing with battlefield terrain. Several military experts explain from different perspectives how to deploy troops in specific terrains:

When encountering advantageous terrain, one should swiftly dispatch elite forces to occupy it first. If the enemy relies on numerical superiority to contest the position, our main forces should attack from the rear in a pincer movement—this strategy never fails to bring victory, as demonstrated by Zhao She's defeat of the Qin army during the Warring States period. Du You adds that when facing favorable terrain, speed is essential—those who arrive first win, while latecomers lose. Therefore, troops must follow up rapidly from behind.

Mei Yaochen argues that if the enemy hasn't yet reached the advantageous position while our forces are behind, we should advance swiftly to seize it. Zhang Yu emphasizes that the key to contesting favorable terrain lies in supernatural speed—if the vanguard arrives but the follow-up troops cannot keep pace, the advantage is lost. Thus, both forward and rear forces must arrive simultaneously, achieving what is called "arriving first by starting later."

When fighting in key transportation hubs (intersection terrain), defenses must be airtight. Du Mu advises strengthening fortifications; Mei Yaochen suggests holding fortresses and cutting enemy supply lines; Wang Xi warns against ambushes; while Zhang Yu proposes that complete roadblocks are unnecessary—simply fortify positions and set ambushes when enemies approach.

In highly accessible regions (hub terrain), alliances with neighboring states must be consolidated. Du Mu stresses forming unshakable bonds with adjacent countries; Mei Yaochen emphasizes establishing alliances earlier than the enemy; Wang Xi believes relationships should be reinforced through virtue, ritual, and authority; Zhang Yu advocates using material incentives and binding treaties to secure steadfast support from allies.

When penetrating deep into enemy territory (critical terrain), provisions must be requisitioned locally. Cao Cao, Li Quan, and Jia Lin all advocate plundering enemy supplies; Du You states that deep penetration requires guaranteed logistics; Mei Yaochen points out that during long campaigns, provisions must be obtained from enemy lands; Zhang Yu adds that transportation difficulties in hostile territory necessitate seizing enemy provisions to maintain supply lines.

When encountering impassable terrain (difficult ground), rapid passage is essential. Cao Cao, Li Quan, and Du You all advocate swift departure; Mei Yaochen states that such terrain offers no support and must be traversed quickly; Zhang Yu recommends leading troops through treacherous paths at top speed.

When trapped in encirclement (encircled terrain), gaps must be sealed. Cao Cao and Li Quan view this as crucial for unifying morale; Du Mu quotes military texts saying...

In military strategy, when surrounding enemy forces, one should intentionally leave an opening. This is not an act of mercy, but rather to make the enemy believe there is still a path to escape, thereby weakening their will to fight desperately to the death. This makes it easier to defeat them when they attempt to break through the encirclement.

A classic example from history: In the late Northern Wei period, when Gao Huan (Emperor Shenwu of Qi) raised his forces in Hebei, four generals including Erzhu Zhao surrounded him with 200,000 elite troops on Nanling Mountain. At the time, Gao Huan had only 2,000 cavalry and fewer than 30,000 infantry. Facing complete encirclement, he deliberately blocked his own army’s retreat with oxen and donkeys. This act of cutting off all escape routes made his soldiers realize that survival depended solely on fighting to the death, ultimately allowing them to defeat a far larger force.

When an army is trapped in a desperate situation, a commander must take extraordinary measures to rally morale: smashing cooking pots, filling in wells, burning provisions and supplies—such "burning one’s boats" tactics demonstrate to the troops that there is no way back. As military strategists like Cao Cao and Li Quan observed, such extreme measures inspire soldiers with the will to "live by facing death." Du Mu further explains that by eliminating all possibility of survival, each soldier is forced to fight with desperate resolve.

The psychological shift in a surrounded army follows a distinct pattern: initially, encirclement triggers defensive instincts, naturally fostering unity among soldiers to resist the enemy. Mei Yaochen notes that this "shared hatred for the enemy" mentality strengthens the army’s cohesion in defense. But when the situation deteriorates to the extreme, this defensive mindset transforms into an explosive determination for a final, decisive battle. As Zhang Yu analyzes, this is a natural human reaction in desperate straits—first, holding firm, and when pushed to the brink, unleashing astonishing combat power.

This passage compiles annotations by military strategists throughout history on the "Nine Terrains" chapter of The Art of War, primarily discussing strategies for armies facing different predicaments.

When an army finds itself in a desperate situation, the commander must fight with total commitment. Mei Yaochen notes that when there is no path of retreat, the only option is to struggle for survival. Wang Xi argues that the sole way to escape death is through combat. Zhang Yu adds that when circumstances demand it, one must exert every ounce of strength in battle.

When trapped in extreme peril, adaptability becomes essential. Cao Cao comments that deep in danger, one must flexibly employ all manner of stratagems. Both Li Quan and Mengshi agree that the more dire the situation, the more crucial it is to heed diverse counsel. Zhang Yu illustrates this with the example of Ban Chao in Shanshan—when facing life-or-death circumstances, soldiers will naturally follow their commander’s orders.

Sunzi emphasizes three critical points: without understanding the intentions of neighboring states, one cannot form alliances in advance; without familiarity with mountainous forests, treacherous passes, or marshy terrain, one cannot march an army; and without employing local guides, one cannot gain the advantages of terrain. Cao Cao identifies these as the fundamentals of warfare. Li Quan considers them the most vital military priorities. Mei Yaochen explains that this reiterates the importance of knowing both the enemy and the land. Wang Xi suggests the repetition serves as a warning to later generations. Zhang Yu concludes that only by grasping these three points can one master the advantages and disadvantages of the nine types of terrain.

If any one of the strategic implications of the nine terrains (or the aforementioned four or five principles) remains unclear, an army cannot become a hegemon capable of dominating the realm. Zhang Yu annotates that even a single gap in understanding makes complete victory difficult to achieve.

A truly hegemon-level army, when attacking a major state, can prevent the enemy from mobilizing its forces; when exerting deterrence, it can disrupt hostile alliances. Li Quan states that by concentrating forces and displaying overwhelming might, neighboring states dare not act rashly. Du Mu argues this requires sufficient strength to divide the enemy. Mengshi points out that none dare resist when one governs with righteousness. Chen Hao adds that even with hegemon-level strength, when attacking a major state, it is essential to secure external support rather than relying solely on intimidation.

This passage primarily discusses how to weaken powerful states and strengthen one's own position through military strategy and diplomatic means. The core argument states:

When attacking a major power, if one can divide its alliances ("divide its supporters"), sufficient military superiority can be maintained. This not only deters the target enemy state but also prevents smaller neighboring states from forming alliances with it out of fear. Just as during the Spring and Autumn period, when Jin and Chu vied for hegemony, Zheng State consistently aligned with the winning side—the allegiance of minor states directly influenced the shifting balance of power between major powers.

A truly dominant hegemon (such as Duke Huan of Qi) need not deliberately court other states or resort to political manipulation; military strength alone suffices to command respect. Duke Huan, following Guan Zhong's advice, first returned neighboring lands to establish goodwill, then solidified his authority through military campaigns like the northern expedition against the Shanrong and the southern campaign against Chu, ultimately becoming the leader of the feudal lords.

Conversely, relying solely on brute force and repeatedly waging war against major powers will only breed resentment among one's own troops and civilians, while other states may unite in fear to resist. The key lies in balancing military deterrence with diplomatic strategy—demonstrating strength while avoiding excessive depletion of resources.

This historical anecdote recounts the struggle for hegemony between the states of Wu and Yue during the Spring and Autumn period. After King Fuchai of Wu defeated Qi at the Battle of Ailing, he vied for supremacy with Jin at the Huangchi Summit, intimidating other feudal lords with his military might. King Goujian of Yue seized the opportunity to attack when Wu's national strength was depleted. Though his appeals for aid to Qi and Chu were rejected, Yue ultimately conquered Wu after exhausting its resources.

Shen Baoxu (a high official of Chu) advised Goujian: "Yue borders Chu to the south, Jin to the west, and Qi to the north, having long curried favor with these powerful states through treasures and beautiful women. To achieve vengeance now, you must concentrate all forces against Wu." Ultimately, Yue succeeded in conquering Wu.

Military strategists offered these insights: When a state possesses sufficient strength, it need not deliberately cultivate foreign alliances or external support. Jia Lin observed that when feudal lords submit out of fear, no deliberate diplomatic maintenance is required. Chen Hao emphasized that formidable military power and comprehensive strategy naturally command respect. Mei Yaochen and Wang Xi both noted that excessive reliance on diplomatic alliances actually diminishes one's authority. Zhang Yu warned that merely venting personal grievances or flaunting military strength inevitably leads to defeat.

A truly powerful army (the hegemon's forces) should: When enemies cannot secure external aid, sever their diplomatic channels; when internal discord arises within enemy ranks, dismantle their power structure. This approach simultaneously enhances one's own prestige while conquering enemy cities.

During extraordinary circumstances (such as besieging cities or conquering states), conventional rules may be broken to implement special rewards and extraordinary decrees. Jia Lin explained this as establishing unique authority through unconventional incentives at critical moments, thus not being bound by ordinary laws and policies.

This passage elucidates several fundamental principles of ancient military command:

Regarding military orders and reward-punishment systems, commentators emphasize that regulations should not be predetermined and publicly displayed, but rather established in response to actual battlefield conditions when facing the enemy. As recorded in The Methods of the Sima, oaths should be sworn upon encountering the foe, and rewards distributed immediately based on military merit—this approach more effectively boosts morale.

Commanding vast armies should feel as effortless as directing a single person. The key lies in implementing clear and swift reward-punishment measures: immediate rewards for merit and instant punishment for offenses. This ensures that even when leading thousands of troops, commanders maintain seamless control like moving one's own limbs.

In military operations, soldiers should only be told what to do, never why. The Tang Dynasty general Pei Xingjian exemplified this when relocating camps—he never explained his reasons to soldiers. Revealing true intentions risks compromising strategy.

Show soldiers the potential gains, never the dangers. Human nature instinctively seeks advantage and avoids harm—knowledge of peril breeds fear.

Finally, the text discusses the "place-troops-in-death-ground" tactic: deploying forces in seemingly hopeless situations actually inspires desperate courage for survival. Like Han Xin arraying his troops with their backs to the river—cut off from retreat, soldiers fought with unmatched ferocity. What appears perilous becomes survivable through desperate combat; what seems like certain doom transforms into deliverance through determined struggle.

This passage recounts two classic military examples of the "placing troops in mortal peril to survive" tactic. The first story involves Han Xin's campaign against Zhao: Han Xin dispatched two thousand light cavalry carrying red banners to ambush from mountain paths, while leading his main force to deploy with their backs to the river. The Zhao army laughed upon seeing the Han forces arrayed against the water, and when Han Xin feigned retreat during battle, they gave chase with their entire army, leaving their camp undefended. The hidden Han troops seized this opportunity to replace all banners with red flags. When the Zhao soldiers returned to find their camp colors changed, chaos ensued, leading to their complete annihilation. After the battle, Han Xin's officers questioned why violating the conventional military principle of "mountains at the back, water in front" had brought victory. He explained this was a tactic to kindle fighting spirit by placing soldiers in desperate straits—only by removing all alternatives would these newly recruited troops fight with absolute determination.

The second example describes Chen Qingzhi of the Southern Dynasties defending Guoyang: After a year-long stalemate against Northern Wei forces, Wei reinforcements attempted to build fortifications behind Chen's position for a pincer attack. Facing demoralized troops, Chen Qingzhi invoked the principle that "only by placing soldiers in death's grasp can they seek life," arguing that retreat would lead to certain annihilation by pursuing enemies, whereas fighting desperately after being encircled offered the sole chance of survival. Both stories exemplify the military wisdom of "thrusting armies into fatal terrain to preserve their lives," demonstrating how deliberately cutting off retreat routes can, under special circumstances, unleash an army's maximum combat potential.

The text recounts several classic examples of numerically inferior forces achieving victory in ancient warfare, focusing on how commanders inspired their troops with a do-or-die mentality to secure success.

The first story describes Tan Daoji (also known as Qingzhi) of the Southern Song Dynasty launching a night raid against the Wei army. Under cover of darkness, he stormed and captured four enemy camps. When facing the remaining nine fortified positions where enemy forces still held numerical superiority, he deliberately displayed the corpses of captured soldiers while beating war drums and raising battle cries, ultimately causing the entire enemy force to collapse.

The second account details Northern Wei general Gao Huan (later Emperor Shenwu of Qi) at the Battle of Hanling Mountain during the late Northern Wei period. Facing four enemy generals including Erzhu Zhao commanding 200,000 troops deployed along the Huan River, Gao Huan had merely 30,000 soldiers. He adopted a circular formation and used oxen and donkeys to block potential retreat routes, making his troops understand survival depended solely on fighting to the death—resulting in a decisive victory. The narrative particularly emphasizes how Gao Huan intentionally left then personally sealed gaps in the encirclement, deliberately cutting off any possibility of retreat.

The third episode tells of Northern Zhou generals Yang Zhong and Da Xiwu rescuing Sima Xiaonan, governor of Northern Yu Province. Leading only 5,000 cavalry deep into 500 li of enemy territory, Da Xiwu grew suspicious of an ambush near Yu Province and wanted to withdraw. Yang Zhong insisted "better to die fighting than retreat to beg for life," personally leading a thousand cavalry by night to the city walls. They successfully extracted Sima Xiaonan's forces, with Yang Zhong personally commanding the rearguard and using stratagems to frighten off pursuers.

Finally, commentator Zhang Yu concludes: When armies are placed in desperate situations, soldiers naturally fight with desperate courage, thereby paradoxically creating pathways to survival. He cites Xiang Yu's legendary crossing of the Zhang River during the Zhao campaign—where the Chu army destroyed cooking pots and sank boats to eliminate retreat—as another example where outnumbered forces defeated the Qin army ten-to-one. These historical cases all validate the military philosophy that "placing troops in mortal danger ensures their survival."

When an army is placed in perilous circumstances, only then can victory or defeat be determined. Mei Yaochen explains: When soldiers are not in dire straits, their minds often lack focus. It is precisely in moments of crisis that success or failure hinges on human action. Zhang Yu adds that when troops follow orders faithfully, the outcome rests entirely in our hands.

The essence of military strategy lies in conforming to the enemy's intentions to mislead them. Cao Cao points out that one must feign foolishness—if the enemy intends to attack, we set ambushes and feign retreat; if they wish to withdraw, we deliberately leave an opening before launching a surprise assault. Li Quan elaborates: When the enemy seeks to attack, we await them with strong defenses; when they seek battle, we counter with unexpected tactics. Whether retreating, laying ambushes, or offering bait, all must align with the enemy's inclinations.

Du Mu provides a detailed explanation: Conforming to the enemy's will means that when we wish to strike but find no weakness in their position, we must conceal our strength and follow their movements without alerting them. For example, if the enemy advances aggressively, we feign weakness and lay ambushes, allowing their arrogance to breed carelessness before seizing the moment to attack. If they attempt to retreat, we deliberately loosen our encirclement, waiting until their guard is down to strike suddenly. Chen Hao summarizes that conforming to the enemy's intent requires no elaborate explanation—simply appear weak when strong, feign retreat when advancing, lulling the enemy into complacency to ensure their defeat.

Mei Yaochen enumerates specific methods: One may feign cowardice, display weakness, simulate disorder, or pretend to retreat, enticing the enemy to underestimate and recklessly advance, thereby allowing us to seize the initiative. Zhang Yu supplements this by noting that when the enemy seeks to advance, lure them deep; when they wish to withdraw, slow the pursuit—always conforming to their intentions while setting traps. History provides the example of the Donghu people demanding the prized steed and consort of Modu Chanyu (the Xiongnu ruler). Modu deliberately indulged their requests, waiting until the Donghu grew complacent before annihilating them in a single decisive strike.

Concentrate forces to strike a single point—even a thousand-mile march can slay the enemy commander. Cao Cao states that by focusing all strength against the foe, even from a thousand miles away, their general can be captured. Du Mu observes that the earlier discussion addressed strategy before detecting enemy vulnerabilities, but once an opportunity is found, one must commit all forces without hesitation, striking decisively even across vast distances.

This passage discusses the tactical application of "achieving victory through skillful maneuvers" in military strategy. Several military theorists emphasize the importance of exploiting an enemy's weaknesses to secure triumph:

Jia Lin suggests luring the enemy into concentrated action through perceived benefits—this allows one to capture their commanders even from a thousand miles away. Mei Yaochen adds that one must first observe enemy movements before launching unexpected ambushes. Wang Xi points out the need to follow the enemy's intentions, then concentrate forces to strike when their defenses are lax—much like Modu Chanyu's thousand-mile campaign to annihilate the Donghu tribe.

Cao Cao and others explain that "skillful maneuvers achieve victory" refers to securing triumph through clever tactics. The key lies in first accommodating the enemy's intentions, then suddenly attacking their leadership.

Regarding pre-battle preparations, Cao Cao advises establishing strategy first, then sealing passes, destroying travel credentials, and severing envoy exchanges. Li Quan interprets this as preventing wavering morale. Du Mu elaborates: sealing passes doesn't mean rejecting enemy envoys, but preventing spies from infiltrating. Even formal envoys must be treated cautiously, lest astute observers like Zhang Mengtan or Lou Jing discern one's vulnerabilities. Mei Yaochen clarifies that "destroying passes and credentials" means eliminating all means of passage to cut off all communication.

These measures aim to maintain secrecy before military action begins, preventing the enemy from preparing defenses. Only after troops are mobilized should normal envoy exchanges resume—this reflects the constant principle of ancient warfare.

In military operations, utmost caution must be exercised to prevent the leakage of confidential information. Zhang Yu explains that once strategies have been formulated in the temple (referring to the imperial court or decision-making level) and military plans finalized, one should seal mountain passes, destroy travel documents, and cut off messenger communications to prevent intelligence leaks. However, if the enemy sends emissaries, they should be received—hence the subsequent statement: "When vulnerabilities appear in the enemy's position, one must swiftly seize the opportunity."

Military planning in the temple must be meticulous and thorough. Cao Cao interprets "诛" (zhu) as meaning governance. Du Mu emphasizes the need for repeated deliberation and refinement, ensuring that strategies for success or failure are determined in the temple before troops are deployed. Mei Yaochen stresses the importance of rigorous and secretive planning in the temple. He Shi advises repeatedly refining the temple's calculations (court decisions) to ensure success. Zhang Yu points out that military affairs are of grave importance and should not be discussed lightly; planning must be conducted with caution and secrecy in the temple to prevent leaks.

When vulnerabilities appear in the enemy's position, one must act swiftly to exploit them. Cao Cao states that when the enemy reveals gaps, immediate attack is necessary. Li Quan believes that when the enemy's decisions are unsettled, rapid action is key. Mengshi explains that "开阖" (kaihe) refers to gaps—when an opportunity arises, it must be seized without delay. Zhang Yu further clarifies that this refers to moments when enemy messengers are in transit or when their decision-making is hesitant; one should capitalize on these openings with speed.

Priority must be given to seizing the enemy's most vital strongholds. Cao Cao advocates occupying advantageous positions. Li Quan proposes attacking the enemy's supply depots and family encampments first. Du Mu argues that anything the enemy relies upon or values highly should be targeted for capture. Mei Yaochen emphasizes the need to first identify and secure the positions the enemy deems most critical.

Operations must be conducted with secrecy and adaptability. Cao Cao advocates the principle of "striking second but arriving first." Du Mu explains that movements should be covert, targeting the enemy's key positions without their awareness. Chen Hao adds that if one occupies a critical position but the enemy does not engage, the effort is wasted—thus, the enemy must first be lured into the intended location. Mei Yaochen suggests subtly revealing false intentions to mislead the adversary.

This passage discusses two key strategies in the art of warfare: seizing the initiative and adaptive flexibility.

Regarding seizing the initiative, it explains that although our side may deliberately set out later, we must arrive at the strategic location before the enemy. Delaying our departure is meant to lure the enemy into action, while arriving first allows us to seize the advantageous terrain the enemy values most. As Wang Xi explains, this is a tactic of strategic deception. The specific method is to first subtly reveal our intention to occupy a certain position, prompting the enemy to rush there, after which our forces can overtake them. The reason for letting the enemy move first is the concern that if we arrive too early, the enemy might not take the bait at all. This is what military strategy calls the "contested ground" tactic—seizing the opportunity by arriving just after the enemy.

As for adaptive flexibility, the phrase "following the rules while adapting to the enemy" (践墨随敌) means adhering to fundamental principles of warfare (where "墨" refers to established laws and discipline) while adjusting flexibly based on the enemy’s movements. As Cao Cao states, warfare has no fixed patterns. Li Quan explains that "墨" here signifies the planned route of march—if one rigidly follows conventional paths, opportunities may be lost. Du Mu elaborates further: in ordinary times, strict military discipline must be maintained, but when a decisive opportunity arises, swift action must be taken. Chen Hao cites the Battle of Chengpu as an example, where Duke Wen of Jin, seeing his army’s disciplined readiness, knew it was time to strike. All commentaries emphasize that while warfare must follow fundamental principles (绳墨), it must also adapt to circumstances.

Finally, the passage uses the metaphors of a "quiet maiden" (处女) and a "fleeing hare" (脱兔): at the outset, appear as meek and unthreatening as a demure girl to lull the enemy into lowering their guard (开户); but once the attack begins, move as swiftly as a darting rabbit, leaving the enemy no time to react. Cao Cao and Li Quan point out that this is a tactic of shifting between apparent weakness and decisive strength, while Du Mu adds that it involves misleading the enemy about our true capabilities before launching a sudden, rapid assault.

This commentary discusses the tactical principle in military strategy of "being still as a maiden, moving like a fleeing hare." Various annotators interpret the essence of offense-defense transition in Sunzi's Art of War from different perspectives.

Mei Yaochen explains that one should initially remain as quiet and disciplined as an unmarried maiden, biding one's time; but once the decision to strike is made, one must act as swiftly and decisively as a hare escaping capture. Wang Xi elaborates further: maintaining maiden-like stillness allows for observing enemy movements and lulling them into complacency by leaving city gates open, while hare-like swiftness means seizing opportunities with rapid action, much like Tian Dan's defense of Jimo that ultimately crushed the Yan forces during the Warring States period.

Zhang Yu's annotation delves deeper: when defending, deliberately appear weak (like a gentle maiden) to make the enemy underestimate you and reveal vulnerabilities; when attacking, strike suddenly and fiercely (like an agile fleeing hare), catching opponents unprepared and rendering them defenseless. The commentary concludes by citing Grand Historian Sima Qian's evaluation of Tian Dan's campaign, demonstrating this tactic's proven effectiveness in actual warfare.

This tactical concept emphasizes two key points: the importance of concealing true intentions, and the resoluteness required when seizing critical opportunities. The historical account of Tian Dan defending Jimo (where the Qi general famously outmaneuvered Yan forces to reclaim lost territory during the Warring States period) stands as a classic example of this military principle in action.