whoever is disloyal to truth is the same to falsehood also.
 Michel de Montaigne, The Essays of Michel de Montaigne (1580). copy citation

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Author Michel de Montaigne
Source The Essays of Michel de Montaigne
Topic falsehood truth
Date 1580
Language English
Reference
Note Translated by Charles Cotton
Weblink http://www.gutenberg.org/files/3600/3600-h/3600-h.htm

Context

“it were a great simplicity in any one to lay any stress either on the countenance or word of a man who has put on a resolution to be always another thing without than he is within, as Tiberius did; and I cannot conceive what part such persons can have in conversation with men, seeing they produce nothing that is received as true: whoever is disloyal to truth is the same to falsehood also. Those of our time who have considered in the establishment of the duty of a prince the good of his affairs only, and have preferred that to the care of his faith and conscience, might have something to say to a prince whose affairs fortune had put into such a posture that he might for ever establish them by only once breaking his word:” source