A dream is a topos where it is made clear that the reality world is a fantasy for Zhuangzi "荘子".

And Zhuangzi "荘子" thinks that the reality world that is constructed by a human language and epistemological intellect is a fantasy. Thus Zhuangzi "荘子" denies the language and the epistemological intellect that support the reality world, and affirms the ontological intellect that is true intellect.

Zhuangzi "荘子" thinks an existing thing is self-realization of the Tao "道" that is the root of existence. In Zhuangzi "荘子", every existing thing receives the Tao "道" that is chaos, and lives for the Tao "道".

In brief, in the world of Zhuangzi "荘子", there is not any difference between Zhuangzi "荘子" and a butterfly. In other words, Wuhua "物化" of Zhuangzi "荘子" is the episode that preachs that a thing lives in the Tao "道" which does self-realization in a thing.