Chinese idiom · 成语
物极必反
Meaning
Things at their extreme must reverse; excess leads to change.
Character by character
Origin and story
philosophical sayingThe Wenzi (文子), in its Jiu Shou and Shang Li chapters, explains that things reverse when they reach an extreme and diminish when excessively full. It uses the sun passing its highest point and the moon waning after fullness to frame advice against self-satisfaction. The Jiu Shou passage presents the teaching as words of Laozi, but this is a passage in the Wenzi, not the exact four-character wording of the received Laozi.
The later idiom condenses that recurring pattern into a warning about excess. It can suggest that relentless pressure provokes resistance or that overindulgence brings trouble. It expresses a traditional way of reasoning by analogy, rather than a guarantee that every situation must reverse on a predictable schedule.
Sources and further reading
In everyday life
每天把孩子的时间排得满满的，可能物极必反，让他更不愿意学习。
Filling every minute of a child's day may backfire and make him even less willing to study.
A warning about excess and reversal, not a reliable prediction of inevitable future improvement.