镜花水月都成空
[jìng huā shuĭ yuè dōu chéng kōng]
'Flowers In Mirror And Moon Reflected In Water All Turned Out To Be Vain', derives from the saying 'flowers in the mirror, moon in the water'. It suggests beautiful things perceived as reality are ephemeral illusions destined ultimately to vanish, urging not attaching firmly to anything impermanent.