Art of War – Chapter 1.5

When the favorable plans are adopted, create a favorable momentum to assist external operations. Momentum means adapting tactics and exercising flexibility in accordance with existing advantages.

Note

Sun Tzu (Sun Wu or Sunzi)

A great military strategist and thinker in ancient China, who lived in the late Spring and Autumn Period. He authored The Art of War, the world’s earliest and most influential military classic. His strategic thoughts have been widely applied in military, politics and management worldwide.

Strategy vs Momentum

Two core concepts in The Art of War. Strategy refers to pre-war planning; momentum refers to dynamic advantages and flexible adjustment during action.

Exercise flexibility (Zhi Quan)

It means taking temporary measures and changing tactics according to real-time situations, instead of rigidly sticking to plans.

Zhuge Liang’s Empty Fort Strategy

To illustrate the concept of “Momentum” (Shi) and “Exercising Flexibility” (Zhi Quan), let us examine one of the most famous stories from the Romance of the Three Kingdoms: Zhuge Liang’s Empty Fort Strategy.

This story perfectly demonstrates how a general can create a “favorable momentum” out of a desperate situation by abandoning the rigid plan and adapting to the reality.

The Crisis

During the Northern Expeditions, the Shu Han strategist Zhuge Liang was stationed at Xicheng with only a small contingent of soldiers. Suddenly, the Wei Kingdom’s formidable general, Sima Yi, appeared with a massive army of 150,000 troops. Zhuge Liang’s original “strategy” (Ji) was to garrison the city, but this plan became obsolete the moment Sima Yi arrived. Zhuge Liang was vastly outnumbered and defenseless.

Creating Momentum (Shi) through Flexibility (Zhi Quan)

Instead of panicking or sticking to the futile plan of defense, Zhuge Liang exercised extreme flexibility (Zhi Quan). He ordered the city gates to be thrown wide open. He had old soldiers sweep the streets while he, dressed in a Taoist robe, sat calmly on the gate tower playing his zither.

The Psychology of “Momentum”

Zhuge Liang understood that “Momentum” is not about physical strength alone, but about perception and advantage.

• The Rigid Plan: If he had closed the gates, Sima Yi would have seen a trapped enemy and attacked immediately.
• The Flexible Move: By opening the gates, Zhuge Liang created an illusion of a trap. He exploited Sima Yi’s cautious nature (an existing psychological advantage).

Sima Yi, suspecting an ambush, believed that such a calm demeanor (“Momentum”) could only mean the city was empty or heavily fortified. He ordered a full retreat.

Zhuge Liang “created a favorable momentum” out of thin air. He did not win through superior numbers (Strategy), but through superior psychological adaptation (Momentum).

計利以聽，乃為之勢，以佐其外；勢者，因利而制權也。