Reversal to the Opposite
This term means a reversal to an original and opposite state. By extension, it also refers to the way changes occur in a relationship of opposites. In this sense, the term has two different meanings: one is that a thing’s attribute or state will under certain circumstances always transform itself to its opposite; the other is that a thing reverts to its original or fundamental state or attribute. The concept of reversal to an opposite is an expression of the ancient Chinese understanding of the rules governing the way things change.
The motion of Dao is transforming into the opposite or returning to the original state; and Dao is soft and humble while it is functioning. (Laozi)
When we understand that east and west are opposites but cannot exist without each other, then we know the functions and positions of things. (Zhuangzi)