Chapter 5
Wu Hou asked, "If our chariots are sturdy, horses well-trained, leaders brave, and soldiers strong, but we suddenly encounter the enemy in disarray, what should we do?"
Wu Qi answered, "In general warfare, during the day we use banners and flags to command, and at night we use gongs and flutes. When signaled to the left, we move left; when signaled to the right, we move right. We advance when the drums are beaten and halt when the gongs are sounded. The first flute signal means to deploy, and the second means to regroup. Those who disobey orders are to be executed. When the army fears and respects authority, and the soldiers follow orders, there is no enemy that cannot be defeated, no formation that cannot be broken."
Wu Hou asked, "What should we do if the enemy outnumbers us?"
Wu Qi answered, "Avoid engaging them on flat terrain and instead intercept them on difficult terrain. Therefore, when facing ten enemies with one, it is best to utilize narrow passes; when facing a hundred with ten, it is best to use difficult terrain; and when facing ten thousand with a thousand, it is best to use blocked areas. If using a small force to launch a sudden attack, beat drums and sound gongs on narrow roads. Even if the enemy is numerous, they will be startled and panicked. Therefore, when using a large force, choose flat terrain; when using a small force, choose difficult terrain."
Wu Hou asked, "The enemy is numerous, well-trained, and brave, with mountains behind and difficult terrain ahead, mountains on the right and water on the left; they have deep ditches and strong defenses, retreat steadily like a mountain, advance swiftly like wind and rain, and have sufficient supplies. It is difficult to maintain a long standoff against them. What should we do?"
Wu Qi answered, "Your question is profound! This cannot be won solely with the power of chariots and cavalry, but requires clever strategies. If we can prepare ten chariots, ten thousand cavalry, and infantry, dividing them into five armies, each responsible for a direction, the enemy will be confused and unsure of our intentions. If the enemy defends strongly to consolidate their forces, we should immediately send a messenger to ascertain their plans. If they heed our advice and withdraw, we should also withdraw. If they ignore our advice and instead kill our messenger and burn our letters, we should launch a five-pronged attack. Do not pursue if victorious, but withdraw quickly if not. If pretending to retreat to lure the enemy, one army should act cautiously and fight fiercely, while the other four, one distracting the enemy in front, one cutting off their rear, and two others moving secretly from the left and right to attack their fortified positions. With five armies attacking together, a favorable situation will arise openly. This is the method to defeat a strong enemy."
Wu Hou asked, "If the enemy approaches, forcing us to engage in battle, and I want to escape but there is no way out, causing the army to be filled with fear, what should we do?"
Wu Qi answered, "The solution to this problem is, if we outnumber the enemy, we can divide our forces to surround them; if the enemy outnumbers us, we can concentrate our forces to attack them continuously. Even if the enemy is numerous, they can be subdued."
Wu Hou asked, "If we encounter the enemy in a valley between hills, with dangerous terrain on both sides and the enemy outnumbering us, what should we do?"
Wu Qi answered, "When encountering unfavorable terrain such as hills, forests, valleys, deep mountains, and large lakes, we should pass through quickly without delay. If suddenly encountering the enemy in a high mountain or deep valley, we must first beat drums and shout to take advantage of the momentum to disrupt the enemy, then advance the archers to the front, maintaining vigilance while considering strategies and observing whether the enemy's formation is disorganized. If the enemy is found to be in disarray, do not hesitate to launch a full attack."
Wu Hou asked, "With mountains on both sides and narrow terrain, if we suddenly encounter the enemy and dare not attack or retreat, what should we do?"
Wu Qi answered, "This is called valley warfare. Even if our forces are numerous, they cannot be fully utilized. We should select elite soldiers to confront the enemy, using swift and agile soldiers with sharp weapons as the vanguard, while dispersing and hiding the chariots and cavalry around them, a few miles away from the vanguard, without exposing our forces. In this way, the enemy will necessarily defend their position and dare not advance or retreat. At this time, [we should use a portion of our forces] to unfurl flags and march out of the mountains to confuse and disturb the enemy, causing them to be filled with fear. Then we should use the chariots and cavalry to challenge the enemy, preventing them from resting. This is the method of valley warfare."
Wu Hou asked, "If we encounter the enemy at a place where water has converged, with the water level high enough to submerge the wheels and axles of chariots, posing a danger of drowning chariots and cavalry, and we have not prepared boats, making it difficult to advance or retreat, what should we do?"
Wu Qi answered, "This is called water warfare. Chariots and cavalry cannot be used and should be temporarily left on the shore. Climb high to observe all directions and make sure to ascertain the water conditions, understand the width of the water surface, and ascertain the depth of the water before we can achieve a surprise victory. If the enemy crosses the water, attack them while they are halfway across."
Wu Hou asked, "When it rains continuously, making it difficult for chariots and horses to move, and we are surrounded by enemies on all sides, causing the entire army to be filled with fear, what should we do?"
Wu Qi answered, "When using chariots in warfare, halt in rainy and muddy conditions and move when the weather is clear and the ground is dry. Choose high ground and avoid low areas. To make chariots move quickly, whether advancing or halting, it is necessary to use roads. If enemy chariots are moving, we can follow their tracks."
Wu Hou asked, "If a violent enemy suddenly arrives, plundering our crops and stealing our cattle and sheep, what should we do?"
Wu Qi answered, "When a violent enemy arrives, we must consider their strength and defend strictly without engaging in battle. When they withdraw at dusk, their loads will be heavy, their minds will be filled with fear, and they will strive to retreat quickly, with gaps inevitably appearing between them. Pursue them at this time to annihilate them."
Wu Qi said, "The general principle of besieging an enemy city is, once the city is captured, to station troops in its government buildings, control and use its original officials, and confiscate its equipment and supplies. Wherever the army goes, it is forbidden to cut down trees, destroy houses, take grain without permission, slaughter livestock, or burn warehouses, to demonstrate that there is no brutality towards the people. If there are those who surrender, they should be allowed and comforted."
