Abstract
This article tries to explain and interpret the discourse ethics of Karl Otto Apel and their last Foundation. In a historic moment where it seems that already not is it must be based anything, in where the ideas have been relined by the forcefulness of the facts, in an era where modernity has been questioned and Postmodernity, is born at a positive moment where democracies totter by lack of dialogue, is necessary to investigate and elucidate the philosophical position of a thinker honest and consistent with his position as Apel. Here I explain what are the philosophical topics of which part to build his own speech. In addition, it examined critically its ethics proposal.