《列子·仲尼》
眼睛即将失明的人，反而能看清细微的毫毛；耳朵将要聋的人，反而能先听见蚊子飞舞的声音；口舌将要失去味觉的人，反而能先辨出淄渑两水滋味的差别；鼻子将要失去嗅觉的人，反而能先闻到烧焦的气味；身体将要僵硬的人，反而能轻快地奔逸；心灵将要糊涂的人，反而先识别是非：所以事物不发展到极点，是不会走向反面的。
目将眇者，先睹秋毫；耳将聋者，先闻蚋飞；口将爽者，先辨淄、渑；鼻将窒者，先觉焦朽；体将僵者，先亟犇佚；心将迷者，先识是非：故物不至者则不反。
People whose eyes are about to go blind can see fine hairs more clearly; people whose ears are about to go deaf can hear the sound of a mosquito flying first; people whose tongues are about to lose their sense of taste can tell the difference between the tastes of Zi and Min water first; People who are about to lose their sense of smell can first smell the burnt smell; people whose bodies are about to become stiff can run fast and easily; people whose minds are about to become confused can first identify right and wrong: so things will not develop to extremes, It will not go to the opposite.