On a Supposed Right to Tell Lies from Benevolent Motives

"On a Supposed Right to Tell Lies from Benevolent Motives" (sometimes translated "On a Supposed Right to Lie because of Philanthropic Concerns") () is a 1797 essay by the philosopher Immanuel Kant in which the author discusses radical honesty.
Content.
In this essay, arguing against the position of Benjamin Constant, "Des réactions politiques", Kant states that:Hence a lie defined merely as an intentionally untruthful declaration to another man does not require the additional condition that it must do harm to another, as jurists require in their definition ("mendacium est falsiloquium in praeiudicium alterius"). For a lie always harms another; if not some human being, then it nevertheless does harm to humanity in general, inasmuch as it vitiates the very source of right [].… All practical principles of right must contain rigorous truth.… This is because such exceptions would destroy the universality on account of which alone they bear the name of principles.