With this article we pretend look for some relatonships between literary discourse in practice and the knowledge construction, precisely for a better improvement in didactic action. In order to prove this hypothesis, we observe principally the expressive and cognitive mechanisms implicits in the process of replacement semantic characterizing the metaphor. In this way, we make a description of some parallelisms and equivalences between the metaphoric discourse behaviour and some of the necessary requisites so that the knowledge has been acquired through a significant learning.