In this essay I try to compare the kantian concept of Wahrhaftigkeit to the foucaultian position about the concept of parresia, at the heart of his research in his last years. After having analyzed the kantian position in the moral, in the giuridic and in the pragmatic field, I explain in wich sense Kant is, according to Tagliapietra definition, a maximalism of verism. In the last part of the essay I show the difference between this maximalist position and the foucaultian character of the Cynic, as it emerges in the cours at the Collége de France “Le courage de la verité”. My thesis is that, while the kantian position is strictly linked to the dispositif of the person, as it is studied by Roberto Esposito, the foucaultian subject of his last courses and books is a subject we can define as “ecological”, so to say that he is definible only in his relation with the others, with the world, with himself and with the truth.