Originally from
《庄子·逍遥游》 (Zhuangzi: Free and Easy Wandering):
『鹏之徙于南冥也,
水击三千里,
抟扶摇而上者九万里』 - 'when the Peng migrates to the Southern Ocean, its wings beat the water for three thousand li, and it rides the whirlwind ninety thousand li upward.' The young Mao Zedong (
毛泽东) famously recycled the line in his 1917 couplet
『自信人生二百年,
会当水击三千里』.