Art of War Chapter 6: Weak and Strong Points — 虚实 Explained

What Chapter 6 is about

Chapter 6, Weak and Strong Points (虚实, traditional 虛實, Xū Shí), is the chapter in which the Art of War teaches a commander how to make the enemy's strength irrelevant and its weakness decisive, rather than meeting the enemy's strength head-on. Its recorded one-line purpose states the method plainly: avoid strength and strike weakness — the art of emptiness and fullness. The chapter develops the paired ideas of xu (虚 — empty, weak, vacant) and shi (实 — full, strong, solid), and shows a commander controlling where and when battle happens, concentrating his own force while dispersing the enemy's, forcing the enemy to reveal itself, and adapting without constant form like water. The pairing of emptiness and fullness lies behind the military method of refusing to fight the enemy's strong points and striking where it is weak or unprepared.

Source and translation notes

The primary source for this page is the Chinese Text Project page for the chapter, https://ctext.org/art-of-war/weak-points-and-strong, which presents the received Chinese text of Chapter 6 under the title 虛實 together with an English translation attributed to Lionel Giles (1910); the source URL is registered here with access date 2026-08-18. At access time the ctext page returned a human-verification (captcha) challenge rather than page content, so this page does not assert the exact ctext page display; the English rendering used here is verified from the Giles 1910 edition (below), and the received Chinese text is verified in-repo through the two registered chapter-6 cards.

The Oriens data record labels the chapter 虚实 (Xū Shí), English "Weak and Strong Points", with the slug weak-and-strong-points. No single printed edition is registered as canonical for chapters 1–12, so this page follows the established site convention: the received text is summarized in careful paraphrase rather than presented through an unregistered translation as a quotation, with quotation limited to at most 25 words. The verified Giles 1910 English edition (Project Gutenberg #132, translator Lionel Giles, original publication 1910) lists "Chapter VI. Weak Points and Strong" in its table of contents; the chapter-6 English renderings presented by ctext are attributed to this same translation, and that is the working English basis used here.

For the appear-unexpectedly / march-through-unoccupied-ground and the water / avoid-the-full / strike-the-empty / no-constant-form passages, the working translation is based on the two registered Chapter 6 card translations — "Attack Where They Are Not" and "Be Shapeless as Water" — both attributed to this chapter (Sunzi Bingfa · 虚实). Other related card material has intentionally not been used here, because it belongs to a different chapter.

The title and its translation boundary

The chapter's Chinese title is 虚实 (traditional 虛實, Xū Shí). The operative terms of the chapter are the paired concepts xu (虚 — empty, weak, vacant) and shi (实 — full, strong, solid). The exact English chapter label differs slightly across surfaces: the site data record renders it "Weak and Strong Points", while Lionel Giles's 1910 heading is "Weak Points and Strong". Both render the same 虚实 chapter and the same xu/shi pair, so this wording difference is a translation-surface note, not a different chapter.

The two concepts are also rendered differently across the registered surfaces: the site subtitle renders the pair as "emptiness and fullness", while the aow-13 card working translation renders them as "the empty" and "the full". These are recorded here as translation-boundary notes. This page does not assert a single "core meaning" of xu/shi; that would require a cited philological or translation source, and none is presented as established here.

Xu and shi: avoiding strength, striking weakness

The chapter turns on a simple asymmetry: an army is not equally strong or equally prepared at every point, and a commander should not meet strength with strength. The received text states that whoever is first in the field and awaits the coming of the enemy will be fresh for the fight, while whoever is second in the field and has to hasten to battle will arrive exhausted. It then states that the clever combatant imposes his will on the enemy, but does not allow the enemy's will to be imposed on him.

The recorded one-line purpose of the chapter is "avoid strength, strike weakness", which is the method that follows from the empty/full asymmetry: one can be sure of succeeding in attacks by attacking places that are undefended, and can ensure the safety of one's defence by holding positions that cannot be attacked. A general is therefore skilful in attack when the opponent does not know what to defend, and skilful in defence when the opponent does not know what to attack. The chapter states emphatically that in war the way is to avoid what is strong and to strike at what is weak, just as water runs away from high places and hastens downwards.

Water and the adaptation of form

The chapter gives its most famous expression of flexibility through the image of water. The received text states that military tactics are like water, for water in its natural course runs away from high places and hastens downwards. Just as water shapes its course according to the nature of the ground over which it flows, so the soldier works out his victory in relation to the foe whom he is facing. And just as water retains no constant shape, so in warfare there are no constant conditions; one who can modify his tactics in relation to his opponent and thereby succeed in winning may be called a heaven-born captain. The chapter closes by illustrating inconstancy through the five elements, the four seasons, the alternation of short and long days, and the moon's phases of waning and waxing.

The registered aow-13 card reproduces the leading passage in Chinese (夫兵形象水，水之形避高而趨下，兵之形避實而擊虛；水因地而制流，兵因敵而制勝；故兵無成勢，無恒形，能因敵變化而取勝者，謂之神) with pinyin and a working translation that renders 兵之形避實而擊虛 as "military disposition avoids the full and strikes the empty", water shaped by the ground and victory shaped by the enemy, and no fixed configuration or constant form. That is the same water/avoid-strike passage rendered by Giles as avoiding what is strong and striking at what is weak.

Concentration and dispersion of forces

The chapter explains how a commander comes to be strong at the point of decision. The received text states that by discovering the enemy's dispositions while remaining invisible ourselves, we can keep our forces concentrated while the enemy's must be divided. We can then form a single united body while the enemy must split up into fractions — a whole pitted against separate parts, so that we are many to the enemy's few. Numerical weakness comes from having to prepare against possible attacks, while numerical strength comes from compelling the adversary to make those preparations.

The means of causing this dispersion is concealment. The chapter states that the spot where we intend to fight must not be made known, because then the enemy will have to prepare against a possible attack at several different points, and with its forces distributed in many directions the numbers we face at any given point will be proportionately few. Should the enemy strengthen its van it will weaken its rear, and so on, so that preparing everywhere leaves one weak everywhere.

The initiative: imposing one's will and forcing the enemy to reveal itself

The chapter repeatedly stresses the initiative — controlling whether, where, and when a battle happens rather than reacting to the enemy. The received text states that if we wish to fight, the enemy can be forced to an engagement even behind a high rampart and a deep ditch, by attacking some other place that he will be obliged to relieve; and if we do not wish to fight, we can prevent the enemy from engaging us even though our encampment be merely traced out on the ground, by throwing something odd and unaccountable in his way. This is the active side of the empty/full method: the commander chooses the point of decision, so the enemy's force spreads to cover what the commander chooses, becoming weak elsewhere.

The chapter also teaches that weakness is to be found out, not guessed at. It states that we should rouse the enemy to learn the principle of his activity or inactivity, and force him to reveal himself so as to find out his vulnerable spots. And through subtlety and secrecy one can be invisible and inaudible to the enemy and hold the enemy's fate in one's hands, advancing irresistibly by making for weak points and retiring in safety if more rapid than the enemy. One should not repeat the tactics which have gained one victory, but let methods be regulated by the infinite variety of circumstances.

Historical context

The Art of War is traditionally attributed to Sunzi (Sun Tzu), a figure of ancient China, but the traditional dating (roughly the sixth to fifth centuries BCE) is a traditional attribution and is not asserted here as a settled fact. The received text is a book of thirteen chapters; Chapter 6 is the sixth in that sequence.

The chapter's substantive instruction is addressed to a general commanding troops in war between states: first-in-the-field freshness, imposing one's will, attacking undefended points, forcing the enemy to reveal itself, concentration versus dispersion, water-like adaptation of form, and the concealment of one's own dispositions are all framed as military command. The Giles edition notes one passage as a reference to the soldiers of Yüeh and the period of struggle between the states of Wu and Yüeh; that reference is recorded here as it appears in the rendering, not asserted beyond it. This page presents no biography of Sunzi, no settled dating, and no account of the courts or kingdoms the text is traditionally tied to; such claims would require their own sources and are out of scope here.

Misreading boundary: what this chapter is not

"Avoid strength, strike weakness" is not a slogan for avoiding all difficulty. In the chapter it is a military method of choosing the ground of battle and forcing the enemy to spread itself thin; it is not a claim that one should never face hard problems, and it is not cowardice.

Xu/shi is not a fixed moral or business binary. The pair is rendered variously (emptiness/fullness, weak/strong, empty/full), and this page does not assert a single "core meaning" of it.

The water metaphor is not passive "go with the flow". In the chapter it is adaptive method with a purpose — the soldier works out victory in relation to the foe; it is not evasion of responsibility.

"No constant form" is not a license to have no principles. It is the statement that in war there are no constant conditions and method must respond to the foe.

Not a business-success or personal-success formula. The received chapter states no promise of business, leadership, or personal success; reading avoid-strength/strike-weakness or water-adaptation as a guarantee of business growth or winning outcomes is an extrapolation beyond the text, and the modern reading below is explicitly labeled interpretation.

No unsupported biography or identity facts. This page presents no birth, death, or court dates for Sunzi and no account of the courts the text is traditionally tied to; the traditional attribution is marked as traditional and unsettled.

A restrained modern reading

Read in the present day, the most defensible transfer of this chapter is about choosing the ground on which you will act rather than being drawn onto the ground where the other side is strongest. Its durable habits are to concentrate effort where it can be decisive rather than spreading it thin in equal preparation everywhere, to adapt one's method to the actual situation rather than repeat fixed tactics, and to seek out the vulnerable point rather than spend force against a strong one. The water image invites a discipline of revising method as circumstances change while keeping a clear purpose.

This reading is explicitly interpretation. The chapter itself is about a general commanding an army in war between states, controlling where battle happens, keeping his own force concentrated, forcing the enemy to disperse, and adapting without constant form. Borrowing its pattern for a non-military situation is a use of the text, not a statement about what the ancient author meant to teach, and it carries no promise of success in any modern setting.

Reading path for this chapter

Chapter 6 is the sixth of thirteen chapters. For readers following the book's own sequence: Art of War Chapter 5: Energy (/guides/art-of-war-chapter-5-energy/) precedes this chapter in the received sequence; its recorded purpose is shi — the strategic advantage that turns ordinary force into overwhelming power. Art of War Chapter 7: Maneuvering (/guides/art-of-war-chapter-7-maneuvering/) follows in the received sequence, used here only as a reading-path target.

See the map: the Art of War complete guide (/guides/art-of-war-complete-guide/) is the 13-chapter reference and navigation owner; the Art of War chapters and reading order (/guides/art-of-war-chapters/) index and the Art of War complete text (/guides/art-of-war-complete-text/) sit alongside it as distinct surfaces. This page's answer is specific to chapter 6 and does not replace any of them.

See the related cards: Attack Where They Are Not (/cards/aow-12-emptiness/) and Be Shapeless as Water (/cards/aow-13-shape-water/) reproduce this chapter's appear-unexpectedly and water passages; they are attributed to Chapter 6 (虚实) and are used here as the working-translation basis.