少年易老学难成，一寸光阴不可轻 “Youth grows old easily, and learning is hard to achieve. Not an inch of time may be taken lightly.” For a long time the poem was believed to be the work of the Song philosopher Zhu Xi.
It does not appear in Zhu Xi’s collected works. The attribution goes back to Japanese school textbooks of classical Chinese from the Meiji era. Japanese scholars have traced the poem to a monk of the Gozan Zen monasteries of the Muromachi period, Kanchu Chutei, whose collection Seihoshu is its oldest known source. A study from Hiroshima University says it can be stated with confidence that Kanchu wrote the poem. Many Chinese sources still credit Zhu Xi.