From
《孟子·告子下》 (Mencius, Gaozi II, c. 300 BCE):
然后知生于忧患,而死于安乐也 (only then do we understand that we live through hardship and die through ease). Mencius cites a roster of ancient figures (
舜、
傅说、
胶鬲...) who rose from obscurity through suffering, arguing that adversity is Heaven's way of preparing great people. The line is a standard text in Chinese middle-school literature.