From
毛泽东's 1965 poem
《水调歌头·重上井冈山》:
世上无难事,
只要肯登攀 - 'In this world there is nothing truly hard, so long as one is willing to climb.' Became one of the most widely quoted motivational lines of late-20th-century mainland culture, a stock motto in schools, workplaces and posters.