It was a utopian and generous project: that of instituting a common universal language to facilitate exchanges and erase the differences between peoples. Only after more than a century of existence, Esperanto has not imposed itself in our exchanges.

This is one of the most beautiful utopias in the world, to finish with Babel. One of the most generous projects, building a language of peace: Esperanto. But alas, Esperanto has not become the language of humanity, it is, as you know, another idiom that has taken its place.

To understand why this language has not imposed itself, Guillaume Erner talks to James Costa, professor of socio-linguistics at the Sorbonne-Nouvelle University.