The Art of War

The Art of War can be divided roughly into four sections: general principles (Chapters 1-3), strategy and tactics (Chapters 4-8), conditions in the field (Chapters 9-11), and special techniques (Chapters 12-13).

The first section, Chapters 1-3, introduce the reader to Sun Tzu’s overarching ideas concerning how to conduct war efficiently and successfully. These principles lay the foundations for strategic thinking. Sun Tzu’s greatest concern is that war is costly—in lives, resources, and the security of the State—and that war should therefore be fought only after careful planning. An expensive, lengthy, and badly thought-out war can bankrupt a state and inspire nearby kingdoms to attack the weakened country.

Sun Tzu doesn’t merely focus on specific strategic and tactical techniques; he also emphasizes the importance of introspection—not the navel-gazing kind that in his mind wastes time, but the type that ferrets out personal weaknesses which interfere with the best decision-making during battle. Sun especially criticizes impatience and irritability, and he advises generals to resist hurry and anger and to take advantage of those weaknesses if they show up among the enemy’s leaders.

Generals also need to make good use of their lieutenants—for example, to encourage the smart ones to innovate, the brave ones to prove their mettle in the field, and the greedy ones to capture enemy facilities. This advice is echoed in the actions of 19th-century German chancellor Otto von Bismarck, who famously divided soldiers into the clever, the diligent, the stupid, and the lazy. He warned against giving authority to the stupidly diligent but praised the cleverly lazy, who can find elegant ways out of difficult situations.

Sun Tzu wants rulers to know how expensive war can be, and he lists the daily cost for an army of 100,000 at 1,000 ounces of silver. A thousand ounces of silver in recent years is worth about $20,000. This a paltry sum in the face of modern industrial-nation living costs for 100,000 persons, which amount to roughly $10 million per day, not counting any weapons they may require. The reader might therefore conclude that war was cheap during Sun Tzu’s time. Instead, silver was worth a lot more 2,500 years ago than it is today—perhaps as much as 1,000 times more. Even 1,000 ounces of gold at today’s prices would pay for only about 10,000 soldiers and weapons. Thus, precious metals in ancient times were especially precious, and warfare was especially expensive.

Warfare today remains costly: Extended military engagements in recent decades involving the US have cost that nation trillions of dollars, with many arguing that these expenditures have caused damage to its economy. A smaller nation involved in a pitched battle with a neighbor can quickly bankrupt itself as easily as Chinese states could 2,500 years ago. Sun Tzu’s advice about wartime cost management remains as cogent now as then.

Near the top of Sun Tzu’s priorities is planning. Strategies are general plans of attack. Tactics are adaptations to specific situations within a battle. Chapter 3, “Attack by Stratagem,” calls attention to a specific type of strategy. Stratagems are strategic subsets that emphasize deceit and manipulation. For Sun Tzu, it is vastly better to defeat an enemy by meddling with its alliances or otherwise weakening it outside the battlefield than simply to attack it head-on. Thus, a peaceful stratagem is preferable to a war strategy. (The use of spies as a stratagem is the topic of Chapter 13).

Stratagems aren’t limited to peacetime. For example, the point of dividing an army in two, when it is twice the size of the opponent, is to lay a trap by making a frontal assault with one half of the army and then attacking suddenly at the enemy’s rear with the other half.

Sun Tzu’s method can be boiled down to three main principles: Plan thoroughly, deceive the enemy, and attack its weak spots. These precepts are developed further in the chapters to come.