IT MEANS CHALLENGING...When Rubén Darío says "Colloquium of the Centaurs in the catorceavo verse: "..., agile and piafantes vigor... " He wanted to say and challenging vigor, referring to the Centaurs to as foals in the forests, they projected as owners of the fields, the sea.Some people mistakenly use the concept and few definitions have the conceptual idea and appropriate language.