2. The four friends of the literati refer to the piano, chess, calligraphy and painting. In ancient times, playing the piano (mostly refers to playing guqin), playing chess (mostly refers to Go), calligraphy and painting were the skills that literati (including some aristocratic families) must master to cultivate their self-cultivation, so they were collectively called "four friends of literati". Nowadays, it often expresses personal cultural accomplishment.
3. Origin: Yan Yuan's Falu, Volume III: "Eloquent people's common surname is Yuan, the great-grandson of Liang. The eloquence is profound, and the piano, chess, calligraphy and painting are wonderful. "