Human beings are born soft and weak. When human life is born, it contains harmony and spirit. Therefore, they are soft and weak. When they die, they become firm and rigid. When a person dies, the harmonious qi is exhausted and the spirit perishes; therefore, it becomes firm and rigid. All things, grasses, and trees are born soft and brittle. Because the harmonious qi exists. When they die, they wither and dry up. Because the harmonious qi departs. Therefore, those who are firm and rigid belong to the category of death, while those who are soft and weak belong to the category of life. Observing these two matters above, one knows that those who are firm and rigid die, while those who are soft and flexible live. Therefore, when an army is too strong, it cannot win. A powerful army engages in light warfare and takes pleasure in killing; its poison spreads and resentment accumulates. Many weak forces unite into one strength, so they cannot be defeated. When a tree is too strong, it will break. If the root is strong and large, then branches and leaves grow together on top of it. Strength and power are in a lower position; softness and weakness are in an upper position. When things arise to create achievements, the great tree is at the bottom, while small objects are on top. The way of Heaven suppresses strength and supports weakness; this is the natural effect.