Transformation is another important idea in dialectical thinking.
Human's concern for the idea Transformation also developed from their observation of nature: the alternate of hotness and coldness, winter and spring; the rise and fall of the sun; the wax and wane of the moon. The idea Transformation was firstly recorded in Book of Change, in which Hexagram Tai and Hexagram Pi embodied the transformation of the opposites, like the lines "The large comes when the small leaves," "The small comes when the large leaves," "There will be no slope without even," "There will be no return without departure," and "Fortune follows after disaster."
In Spring and Autumn Period, the idea Transformation was widely acknowledged and discussed by many philosophers:
Cai Mo [Shi Mo] cited the line in Classic of Poetry: A high bank can be called valley, and a deep valley can be called hill. (Zuo Zhuan, The 32nd Year of the Reign of Duke Zhao)
Love is the start of hate; good is the source of evil. (Guan Zi, Guan Zi, On Tao)
These opinions suggested that philosophers in Spring and Autumn Period had realized that the opposites of things were contained in the things themselves. In late Spring and Autumn Period, Sun Tzu extended the idea Transformation to military field: "The disturbance comes from the peace, the timidity from the valor, and the weakness from the strength. (The Art of War, Energy) More importantly, Sun Tzu noticed the military use of the idea Transformation:
Only put in danger can soldiers turn the danger to safety; only put in peril can soldiers turn the peril to hope. (The Nine Situations)
That showed how one's disadvantage transformed to advantage.
For the enemy, the comfort can tire them, the satiety can hunger them, and the rest can disturb them. (The False and the Real)
That showed how enemy's advantage transformed to disadvantage. The idea Transformation was viewed as an approach of great significance. It confirmed the authenticity of dialectics and constituted a prominent feature of Chinese philosophy.
However, it was Lao Tzu who endowed the idea Transformation with philosophical meaning. Based on wide observation and deep thinking, Lao Tzu discovered the universality of Transformation:
What seems natural may seems strange; what looks good may seems evil. (Lao Tzu, Chapter 58)
The army that seems too invincible may lose; the tree that seems to hard may break. (Chapter 76)
The movement of Tao means the endless transformation of the opposites. (Chapter 40)
Things will decline when they have reached the full development. (Chapter 55)
Things will develop in the opposite direction when they become extreme. This is the eternal law in nature. Theses famous remarks had become the symbol of the wisdom not only in Lao Tzu's philosophy but in Chinese philosophy Akin to Sun Tzu, Lao Tzu also considered the appliance of the idea Transformation, and his thoughts embodied more philosophical color than Sun Tzu. Lao Tzu proposed two paradigms for transformation. The first was to promote the transformation: "To contract one thing, man must first expand it; to weaken one thing, man must first strengthen it; to abolish one thing, man must first popularize it; to seize one thing, man must first abandon it." (Chapter 36) The second was to defer the transformation: "Man can make himself safe if he compromises; branch can make itself straight if it bends. Emptiness will turn to fullness; oldness will turn to newness. Man can obtain more if he hopes less; man can delude himself if he hopes more." (Chapter 22) We must admire Lao Tzu's wisdom. Of course, it is also the wisdom of Chinese.
In the Warring States period, Commentaries on Book of Change developed the idea Transformation into a new stage. Like Lao Tzu, Commentaries on Book of Change also believed transformation was common and that transformation was a circular process:
The moon rises when the sun falls and the sun rises when the moon falls; the alternate of the sun and moon creates the day. Summer comes when winter leaves and winter comes when summer leaves; the change of winter and summer forms the year. (A7 Ci IT)
To open and close forms the change; to come and leave incessantly means fluency. (A7 Ci I)
In fact, human can conclude that things are circular if they admit the idea Transformation as Lao Tzu did. Meanwhile, Commentaries on Book of Change observed that transformation commenced when things became extreme: "Man should change when he is at the end of his tether, as to change will result in new direction and new direction will result in long. (Xi Ci II) However, Commentaries on Book of Change and Lao Tzu took different strategies for transformation. Generally speaking, Lao Tzu viewed that things should seem weak to avoid or defer transformation, whereas Commentaries on Book of Change stressed the hard (Gang) side of things. To defer the transformation, Commentaries on Book of Change suggested that: On the one hand, man should be prepared for danger in times of safety: "A gentleman should remind himself of the danger when in safety, of fall when in rise, and of disturbance when in peace." (Xi Ci IT) On the other hand, man should discard the old and favor the new and always reform himself: "To learn the nature means great accomplishment; to progress everyday means great virtue; and to change ceaselessly means Yi. (Xi Ci II)
As above-mentioned, ancient Chinese philosophers made deep thinking on the idea Transformation as early as in the Sping and Autumn and the Warring States periods. They dealt with both objective laws and subjective methods, thus developed the idea Transformation into a high level. The idea Transformation had been indicated in the history of Chinese philosophy. For instance, Cheng Yi claimed, "Things will turn to the opposite when they reach the extreme." (Cheng's Notes on Commentaries on Book of Change, Vol.1) Zhu Xi said, "When the line moves from the Yin to Yang or from Yang to Yin, man should advance or retreat." (Words of Zhu Zi, Vol. 74)