顾北凉梦南笙一梦
[gù bĕi liáng mèng nán shēng yī mèng]
Perhaps referring to 'Dreams in Northern Liang watched over and Dreams on the Southern Pipe'. These could be metaphors for two contrasting aspects of dreaming—one more watchful (the dream about northern land, signifying solemnness or cool-headed reflection), the other playful or sorrowful (the pipe, indicating the warmth or bitterness associated with human emotions and memories).