This article takes as a starting point Myriam Revault d’Allonnes’s book The Weakness of Truth. While M.R.A. draws upon a wide philosophical range that goes from Plato to our age, passing through important phases of political philosophy, this article wants to take a certain distance from M.R.A.’s sources, and it confines itself to considerations of moral philosophy and to the politics of a few modern and contemporary authors. Starting with considerations on current topics, our paper goes back to a past situation more or less similar to the Brexit – the American retreat from the League of Nations right after World War I – and then it focuses on the disparity between reality and mental images whose origins can be found in the discourses on World War I and the situation it created. It also shows the tendency to present fake news with democratic aims in texts belonging to the very beginnings of the modern era. It is in this reading of moderns of different ages that, in our opinion, we can find the way towards the transcending of our era, not yet transcended in our customs, of fake news and post-truth, while taking into account the current weakness of a moral vision on the contemporary.