《庄子·外篇·田子方》
消亡又生息，盈满又空虚，一暗一明，日日改变，月月转化，每日有所作为而不见其功效。
消息满虚，一晦一明，日改月化，日有所为而莫见其功。
Extinction and then life, fullness and then emptiness, darkness and then light, changing day by day, transforming month by month, doing something every day but not seeing its effect.