*Is truth to be told to an insane person*, when it might be dangerous to him or to others? May not he be deceived for his benefit, decoyed into a place of safe detention, or deterred by falsehood from some intended act of violence? Those who have the guardianship of the insane are unanimous in the opinion that falsehood, when discovered by them, is always attended with injurious consequences, and that it should be resorted to only when imperatively required for their immediate safety or for that of others. But in such cases the severest moralist could not deny the necessity, and therefore the right, of falsehood. But it would be falsehood in form, and not in fact. Truth-telling implies two conscious parties. The statement from which an insane person will draw false inferences, and which will drive him to an act or paroxysm of madness, is not truth to him. The statement which is indispensable to his safety, repose, or reasonable conduct, is virtually true to him, inasmuch as it conveys impressions as nearly conformed to the truth as he is capable of receiving. *Is falsehood justifiable for the safety of one’s own life or that of others?* This is a broad question, and comprehends a very wide diversity of cases. It includes the cases, in which the alternative is to deny one’s political or religious convictions, or to suffer death for the profession of them. Here, however, there can be no difference of opinion. Political freedom and religious truth have been, in past ages, propagated more effectively by martyrdoms, than by any other instrumentality; and no men have so fully merited the gratitude and reverence of their race as those who have held the truth dearer than life.