四大皆空

lit. the four elements are vanity (idiom) / this world is an illusion

four / 4

the four elements: earth, water, fire, and wind (Buddhism) / the four freedoms: speaking out freely, airing views fully, holding great debates, and writing big-character posters, 大鳴大放|大鸣大放[da4 ming2 da4 fang4], 大辯論|大辩论[da4 bian4 lun4], 大字報|大字报[da4 zi4 bao4] (PRC)

see 大夫[dai4 fu5]

big; large; great / older (than another person) / eldest (as in 大姐[da4 jie3]) / greatly; freely; fully / (dialect) father / (dialect) uncle (father's brother)

all / each and every / in all cases

empty / air / sky / in vain

to empty / vacant / unoccupied / space / leisure / free time