What is a dream butterfly

Dream butterfly: also known as "butterfly". During the Warring States Period, Zhuangzi once dreamed that he had changed into a butterfly. After metaphor dream, dream. Later generations used it to refer to confused dreams and changing things.

Tang Li Shangyin "Untied" : "Zhuang Shengxiao dream fan butterfly, Wang Emperor spring heart to cuckoo."

Song Lu You "Idle tour" 3: "sleepy sleepy window body butterfly, drunk question element wall word perch crow."